Andrew H. Slattengren, DO

Penny E, a 48-year-old woman with a history of asthma, presents with wheezing and respiratory distress. There are no clinical signs of deep vein thrombosis or hemoptysis. PE is not your most likely diagnosis, but it is included in the differential, so you order a D-dimer concentration. It returns at 700 ng/mL. Should you order CT pulmonary angiography (CTPA) to evaluate for PE?

PE is the third most common type of cardiovascular disease after coronary artery disease and stroke, with an estimated incidence in the United States of 1-2/1000 individuals and a 30-day mortality rate between 10% and 30%.² Improved adherence to a clinical decision support system has been shown to significantly decrease the number of diagnostic tests performed and the number of diagnostic failures.³

A diagnostic algorithm that includes the Wells criteria and a D-dimer concentration can exclude PE without CTPA in 20% to 30% of patients.⁴ However, due to the complexity of the algorithm and insuf­ficient time in busy emergency departments, ad­herence to recommended diagnostic strategies is variable.⁵

Further, it is common for a D-dimer test to be obtained before clinical assessment by a provider.⁶ A fixed cutoff D-dimer concentration of 500 ng/mL is commonly used, despite an absolute reduction of 11.6% in the need for CTPA using an age-adjusted D-dimer concentration threshold (age × 10 ng/mL for patients older than 50).⁷

Three items of the original Wells criteria—clinical signs of deep vein thrombosis, hemoptysis, and whether PE is the most likely diagnosis—are the most predictive for PE.⁸ The development of a more efficient algorithm based on these 3 items that uses differential D-dimer concentration thresholds could retain sensitivity and decrease unnecessary CTPA. Decreasing CTPA would avoid contrast-induced nephropathy and decrease cancers associated with radiation exposure.^9-11 Significant cost savings could also be achieved, as the estimated cost of one CTPA is $648, while a D-dimer concentration is estimated to cost $14.¹²

STUDY SUMMARY

Simplified algorithm diagnoses PE with fewer CTPAs

The YEARS study was a prospective cohort study conducted in 12 hospitals in the Netherlands that included 3616 patients with clinically suspected PE.¹ A total of 151 patients met exclusion criteria (life expectancy < 3 months, ongoing anticoagulation treatment, pregnancy, and contraindication to CTPA). Investigators managed the remaining 3465 study patients according to the YEARS algorithm, which calls for obtaining a D-dimer concentration in all patients and assessing for the 3 items in the YEARS clinical decision rule: clinical signs of deep vein thrombosis; hemoptysis; and whether PE was the most likely diagnosis.

PE was considered excluded if a patient had a D-dimer concentration < 1000 ng/mL and no positive YEARS items or if the patient had a D-dimer concentration < 500 ng/mL and 1 or more YEARS items. The primary outcome was venous thromboembolism (VTE) events at 3 months’ follow-up once PE was excluded. The secondary outcome was the number of required CTPAs using the YEARS decision rule compared with the number that would have been required if the Wells diagnostic algorithm had been implemented.

[polldaddy:10428150]

Continue to: Of the 1743 patients...

Of the 1743 patients who had none of the 3 YEARS items, 1320 had a D-dimer concentration below the 1000-ng/mL threshold. Of the 423 who had a D-dimer ≥ 1000 ng/mL, 55 had PE confirmed by CTPA. In the 1722 patients who had at least 1 YEARS item, 1391 had a D-dimer concentration ≥ 500 ng/mL threshold; 401 of them had PE confirmed by CTPA.

Eighteen of the 2964 patients who had PE ruled out by the YEARS algorithm at baseline were found to have symptomatic VTE during the follow-up period (0.61%), with 6 patients (0.20%) sustaining a fatal PE. The 3-month incidence of VTE in patients who did not have CTPA was 0.43%, which is similar to the 0.34% reported in a previous meta-analysis of the Wells rule algorithm.¹³ Overall, fatal PE occurred in 0.3% of patients in the YEARS cohort vs 0.6% in a meta-analysis of studies using standard algorithms.¹⁴

Using an intention-to-diagnose analysis, 1611 (46%) patients did not have a CTPA indicated by the YEARS algorithm compared with 1174 (34%) using the Wells algorithm, for an absolute difference of 13% and estimated cost savings of $283,176 in this sample. The per-protocol analysis also had a decrease of CTPA examinations in favor of the YEARS algorithm, ruling out 1651 (48%) patients—a decrease of 14% and an estimated savings of $309,096.

WHAT’S NEW

High-level evidence says 14% fewer CTPAs

The YEARS study provides a high level of evidence that a new, simple diagnostic algorithm can reliably and efficiently exclude PE and decrease the need for CTPA by 14% (absolute difference) when compared with using the Wells rule and fixed D-dimer threshold of < 500 ng/mL.

CAVEATS

No adjusting D-dimer for age

The YEARS criteria do not consider an age-adjusted D-dimer threshold, which has been shown to further decrease CTPA use.⁶ This does not preclude the use of the YEARS criteria; applying age-adjusted D-dimer thresholds would have led to an absolute reduction of 8.7% in CTPA.⁷

Continue to: CHALLENGES TO IMPLEMENTATION

None to speak of

We see no challenges to the implementation of this recommendation.

ACKNOWLEDGEMENT

The PURLs Surveillance System was supported in part by Grant Number UL1RR024999 from the National Center For Research Resources, a Clinical Translational Science Award to the University of Chicago. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Center For Research Resources or the National Institutes of Health.

Copyright © 2019. The Family Physicians Inquiries Network. All rights reserved.

Reprinted with permission from the Family Physicians Inquiries Network and The Journal of Family Practice (2019;68[5]:286-287,295).

Penny E, a 48-year-old woman with a history of asthma, presents with wheezing and respiratory distress. There are no clinical signs of deep vein thrombosis or hemoptysis. PE is not your most likely diagnosis, but it is included in the differential, so you order a D-dimer concentration. It returns at 700 ng/mL. Should you order CT pulmonary angiography (CTPA) to evaluate for PE?

PE is the third most common type of cardiovascular disease after coronary artery disease and stroke, with an estimated incidence in the United States of 1-2/1000 individuals and a 30-day mortality rate between 10% and 30%.² Improved adherence to a clinical decision support system has been shown to significantly decrease the number of diagnostic tests performed and the number of diagnostic failures.³

A diagnostic algorithm that includes the Wells criteria and a D-dimer concentration can exclude PE without CTPA in 20% to 30% of patients.⁴ However, due to the complexity of the algorithm and insuf­ficient time in busy emergency departments, ad­herence to recommended diagnostic strategies is variable.⁵

Further, it is common for a D-dimer test to be obtained before clinical assessment by a provider.⁶ A fixed cutoff D-dimer concentration of 500 ng/mL is commonly used, despite an absolute reduction of 11.6% in the need for CTPA using an age-adjusted D-dimer concentration threshold (age × 10 ng/mL for patients older than 50).⁷

Three items of the original Wells criteria—clinical signs of deep vein thrombosis, hemoptysis, and whether PE is the most likely diagnosis—are the most predictive for PE.⁸ The development of a more efficient algorithm based on these 3 items that uses differential D-dimer concentration thresholds could retain sensitivity and decrease unnecessary CTPA. Decreasing CTPA would avoid contrast-induced nephropathy and decrease cancers associated with radiation exposure.^9-11 Significant cost savings could also be achieved, as the estimated cost of one CTPA is $648, while a D-dimer concentration is estimated to cost $14.¹²

STUDY SUMMARY

Simplified algorithm diagnoses PE with fewer CTPAs

The YEARS study was a prospective cohort study conducted in 12 hospitals in the Netherlands that included 3616 patients with clinically suspected PE.¹ A total of 151 patients met exclusion criteria (life expectancy < 3 months, ongoing anticoagulation treatment, pregnancy, and contraindication to CTPA). Investigators managed the remaining 3465 study patients according to the YEARS algorithm, which calls for obtaining a D-dimer concentration in all patients and assessing for the 3 items in the YEARS clinical decision rule: clinical signs of deep vein thrombosis; hemoptysis; and whether PE was the most likely diagnosis.

PE was considered excluded if a patient had a D-dimer concentration < 1000 ng/mL and no positive YEARS items or if the patient had a D-dimer concentration < 500 ng/mL and 1 or more YEARS items. The primary outcome was venous thromboembolism (VTE) events at 3 months’ follow-up once PE was excluded. The secondary outcome was the number of required CTPAs using the YEARS decision rule compared with the number that would have been required if the Wells diagnostic algorithm had been implemented.

[polldaddy:10428150]

Continue to: Of the 1743 patients...

Of the 1743 patients who had none of the 3 YEARS items, 1320 had a D-dimer concentration below the 1000-ng/mL threshold. Of the 423 who had a D-dimer ≥ 1000 ng/mL, 55 had PE confirmed by CTPA. In the 1722 patients who had at least 1 YEARS item, 1391 had a D-dimer concentration ≥ 500 ng/mL threshold; 401 of them had PE confirmed by CTPA.

Eighteen of the 2964 patients who had PE ruled out by the YEARS algorithm at baseline were found to have symptomatic VTE during the follow-up period (0.61%), with 6 patients (0.20%) sustaining a fatal PE. The 3-month incidence of VTE in patients who did not have CTPA was 0.43%, which is similar to the 0.34% reported in a previous meta-analysis of the Wells rule algorithm.¹³ Overall, fatal PE occurred in 0.3% of patients in the YEARS cohort vs 0.6% in a meta-analysis of studies using standard algorithms.¹⁴

Using an intention-to-diagnose analysis, 1611 (46%) patients did not have a CTPA indicated by the YEARS algorithm compared with 1174 (34%) using the Wells algorithm, for an absolute difference of 13% and estimated cost savings of $283,176 in this sample. The per-protocol analysis also had a decrease of CTPA examinations in favor of the YEARS algorithm, ruling out 1651 (48%) patients—a decrease of 14% and an estimated savings of $309,096.

WHAT’S NEW

High-level evidence says 14% fewer CTPAs

The YEARS study provides a high level of evidence that a new, simple diagnostic algorithm can reliably and efficiently exclude PE and decrease the need for CTPA by 14% (absolute difference) when compared with using the Wells rule and fixed D-dimer threshold of < 500 ng/mL.

CAVEATS

No adjusting D-dimer for age

The YEARS criteria do not consider an age-adjusted D-dimer threshold, which has been shown to further decrease CTPA use.⁶ This does not preclude the use of the YEARS criteria; applying age-adjusted D-dimer thresholds would have led to an absolute reduction of 8.7% in CTPA.⁷

Continue to: CHALLENGES TO IMPLEMENTATION

None to speak of

We see no challenges to the implementation of this recommendation.

ACKNOWLEDGEMENT

The PURLs Surveillance System was supported in part by Grant Number UL1RR024999 from the National Center For Research Resources, a Clinical Translational Science Award to the University of Chicago. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Center For Research Resources or the National Institutes of Health.

Copyright © 2019. The Family Physicians Inquiries Network. All rights reserved.

Reprinted with permission from the Family Physicians Inquiries Network and The Journal of Family Practice (2019;68[5]:286-287,295).

Penny E, a 48-year-old woman with a history of asthma, presents with wheezing and respiratory distress. There are no clinical signs of deep vein thrombosis or hemoptysis. PE is not your most likely diagnosis, but it is included in the differential, so you order a D-dimer concentration. It returns at 700 ng/mL. Should you order CT pulmonary angiography (CTPA) to evaluate for PE?

PE is the third most common type of cardiovascular disease after coronary artery disease and stroke, with an estimated incidence in the United States of 1-2/1000 individuals and a 30-day mortality rate between 10% and 30%.² Improved adherence to a clinical decision support system has been shown to significantly decrease the number of diagnostic tests performed and the number of diagnostic failures.³

A diagnostic algorithm that includes the Wells criteria and a D-dimer concentration can exclude PE without CTPA in 20% to 30% of patients.⁴ However, due to the complexity of the algorithm and insuf­ficient time in busy emergency departments, ad­herence to recommended diagnostic strategies is variable.⁵

Further, it is common for a D-dimer test to be obtained before clinical assessment by a provider.⁶ A fixed cutoff D-dimer concentration of 500 ng/mL is commonly used, despite an absolute reduction of 11.6% in the need for CTPA using an age-adjusted D-dimer concentration threshold (age × 10 ng/mL for patients older than 50).⁷

Three items of the original Wells criteria—clinical signs of deep vein thrombosis, hemoptysis, and whether PE is the most likely diagnosis—are the most predictive for PE.⁸ The development of a more efficient algorithm based on these 3 items that uses differential D-dimer concentration thresholds could retain sensitivity and decrease unnecessary CTPA. Decreasing CTPA would avoid contrast-induced nephropathy and decrease cancers associated with radiation exposure.^9-11 Significant cost savings could also be achieved, as the estimated cost of one CTPA is $648, while a D-dimer concentration is estimated to cost $14.¹²

STUDY SUMMARY

Simplified algorithm diagnoses PE with fewer CTPAs

The YEARS study was a prospective cohort study conducted in 12 hospitals in the Netherlands that included 3616 patients with clinically suspected PE.¹ A total of 151 patients met exclusion criteria (life expectancy < 3 months, ongoing anticoagulation treatment, pregnancy, and contraindication to CTPA). Investigators managed the remaining 3465 study patients according to the YEARS algorithm, which calls for obtaining a D-dimer concentration in all patients and assessing for the 3 items in the YEARS clinical decision rule: clinical signs of deep vein thrombosis; hemoptysis; and whether PE was the most likely diagnosis.

PE was considered excluded if a patient had a D-dimer concentration < 1000 ng/mL and no positive YEARS items or if the patient had a D-dimer concentration < 500 ng/mL and 1 or more YEARS items. The primary outcome was venous thromboembolism (VTE) events at 3 months’ follow-up once PE was excluded. The secondary outcome was the number of required CTPAs using the YEARS decision rule compared with the number that would have been required if the Wells diagnostic algorithm had been implemented.

[polldaddy:10428150]

Continue to: Of the 1743 patients...

Of the 1743 patients who had none of the 3 YEARS items, 1320 had a D-dimer concentration below the 1000-ng/mL threshold. Of the 423 who had a D-dimer ≥ 1000 ng/mL, 55 had PE confirmed by CTPA. In the 1722 patients who had at least 1 YEARS item, 1391 had a D-dimer concentration ≥ 500 ng/mL threshold; 401 of them had PE confirmed by CTPA.

Eighteen of the 2964 patients who had PE ruled out by the YEARS algorithm at baseline were found to have symptomatic VTE during the follow-up period (0.61%), with 6 patients (0.20%) sustaining a fatal PE. The 3-month incidence of VTE in patients who did not have CTPA was 0.43%, which is similar to the 0.34% reported in a previous meta-analysis of the Wells rule algorithm.¹³ Overall, fatal PE occurred in 0.3% of patients in the YEARS cohort vs 0.6% in a meta-analysis of studies using standard algorithms.¹⁴

Using an intention-to-diagnose analysis, 1611 (46%) patients did not have a CTPA indicated by the YEARS algorithm compared with 1174 (34%) using the Wells algorithm, for an absolute difference of 13% and estimated cost savings of $283,176 in this sample. The per-protocol analysis also had a decrease of CTPA examinations in favor of the YEARS algorithm, ruling out 1651 (48%) patients—a decrease of 14% and an estimated savings of $309,096.

WHAT’S NEW

High-level evidence says 14% fewer CTPAs

The YEARS study provides a high level of evidence that a new, simple diagnostic algorithm can reliably and efficiently exclude PE and decrease the need for CTPA by 14% (absolute difference) when compared with using the Wells rule and fixed D-dimer threshold of < 500 ng/mL.

CAVEATS

No adjusting D-dimer for age

The YEARS criteria do not consider an age-adjusted D-dimer threshold, which has been shown to further decrease CTPA use.⁶ This does not preclude the use of the YEARS criteria; applying age-adjusted D-dimer thresholds would have led to an absolute reduction of 8.7% in CTPA.⁷

Continue to: CHALLENGES TO IMPLEMENTATION

None to speak of

We see no challenges to the implementation of this recommendation.

ACKNOWLEDGEMENT

The PURLs Surveillance System was supported in part by Grant Number UL1RR024999 from the National Center For Research Resources, a Clinical Translational Science Award to the University of Chicago. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Center For Research Resources or the National Institutes of Health.

Copyright © 2019. The Family Physicians Inquiries Network. All rights reserved.

Reprinted with permission from the Family Physicians Inquiries Network and The Journal of Family Practice (2019;68[5]:286-287,295).

ILLUSTRATIVE CASE

Penny E is a 48-year-old woman with a history of asthma who presents with wheezing and respiratory distress. There are no clinical signs of deep vein thrombosis or hemoptysis. Pulmonary embolism (PE) is not your most likely diagnosis, but it is included in the differential, so you order a D-dimer concentration and it returns at 700 ng/mL. Should you order computed tomography pulmonary angiography (CTPA) to evaluate for PE?

PE is the third most common type of cardiovascular disease after coronary artery disease and stroke, with an estimated incidence in the United States of 1-2 people/1000 population and a 30-day mortality rate between 10% and 30%.² Improved adherence to a clinical decision support system has been shown to significantly decrease the number of diagnostic tests performed and the number of diagnostic failures.³

The use of a diagnostic algorithm that includes the Wells’ criteria and a D-dimer concentration can exclude PE without CTPA in 20% to 30% of patients.⁴ However, due to the complexity of the algorithm and insufficient time in busy emergency departments, adherence to recommended diagnostic strategies is variable.⁵

Further, it is common for a D-dimer test to be obtained before clinical assessment by a provider.⁶ A fixed cutoff D-dimer concentration of 500 ng/mL is commonly used despite an absolute reduction of 11.6% (95% confidence interval [CI], 10.5-12.9) in the need for CTPA using an age-adjusted D-dimer concentration threshold (age × 10 ng/mL for patients > 50 years).⁷

Three items of the original Wells’ criteria—clinical signs of deep vein thrombosis, hemoptysis, and whether PE is the most likely diagnosis—are the most predictive for PE.⁸ The development of a more efficient algorithm based on these 3 items that uses differential D-dimer concentration thresholds could retain sensitivity and decrease unnecessary CTPAs. Decreasing CTPAs would avoid contrast-induced nephropathy and decrease cancers associated with radiation exposure.^9-11 Significant cost savings could also be achieved, as the estimated cost of one CTPA is $648, while a D-dimer concentration is estimated to cost $14.¹²

STUDY SUMMARY

Simplified algorithm diagnoses PE with fewer CTPAs

The YEARS study was a prospective cohort study conducted in 12 hospitals in the Netherlands that included 3616 patients with clinically suspected PE.¹ After excluding 151 patients who met exclusion criteria (life expectancy < 3 months, ongoing anticoagulation treatment, pregnancy, and contraindication to CTPA), investigators managed 3465 study patients according to the YEARS algorithm. This algorithm called for obtaining a D-dimer concentration in all patients and assessment using the YEARS clinical decision rule, consisting of 3 items assessed by an attending physician: clinical signs of deep vein thrombosis, hemoptysis, and whether PE was the most likely diagnosis. PE was considered excluded if a patient had no positive YEARS items and a D-dimer concentration < 1000 ng/mL or if the patient had one or more YEARS items and a D-dimer concentration < 500 ng/mL. The primary outcome was venous thromboembolism (VTE) events at 3 months’ follow-up once PE was excluded. The secondary outcome was the number of required CTPAs using the YEARS decision rule compared with the number that would have been required if the Wells’ diagnostic algorithm had been implemented.

Of the 1743 patients who had none of the 3 YEARS items, 1320 had a D-dimer concentration below the 1000 ng/mL threshold. Fifty-five of the 423 who had a D-dimer ≥ 1000 ng/mL had confirmed PE by CTPA. In the 1722 patients who had at least 1 YEARS item, 1391 had a D-dimer concentration ≥ 500 ng/mL threshold; 401 of those 1391 had PE confirmed by CTPA.

Continue to: Eighteen of the 2964 patients...

Eighteen of the 2964 patients who had PE ruled out by the YEARS algorithm at baseline were found to have symptomatic VTE during the follow-up period (0.61%; 95% CI, 0.36-0.96), with 6 patients (0.20%; 95% CI, 0.07-0.44) sustaining a fatal PE. The 3-month incidence of VTE in patients who did not have CTPA was 0.43% (95% CI, 0.17-0.88), which is similar to the 0.34% (0.036-0.96) reported in a previous meta-analysis of the Wells’ rule algorithm.¹³ Overall, fatal PE occurred in 0.3% (95% CI, 0.12-0.78) of patients in the YEARS cohort vs 0.6% (0.4-1.1) in a meta-analysis of studies using standard algorithms.¹⁴

The new diagnostic algorithm reduced the use of CT pulmonary angiography by 14% and produced a cost savings of $309,096.

Using an intention-to-diagnose analysis, 1611 (46%) patients did not have a CTPA indicated by the YEARS algorithm compared with 1174 (34%) using the Wells’ algorithm, for an absolute difference of 13% (95% CI, 10-15) and estimated cost savings of $283,176 in this sample. The per-protocol analysis also had a decrease of CTPA examinations in favor of the YEARS algorithm, ruling out 1651 (48%) patients—a decrease of 14% (95% CI, 12-16) and an estimated savings of $309,096.

WHAT’S NEW

High-level evidence says 14% fewer CTPAs

The YEARS study provides a high level of evidence that a new, simple diagnostic algorithm can reliably and efficiently exclude PE and decrease the need for CTPA by 14% (absolute difference; 95% CI, 12-16) when compared with using the Wells’ rule and fixed D-dimer threshold of < 500 ng/mL.

CAVEATS

No adjusting D-dimer for age

The YEARS criteria does not consider an age-adjusted D-dimer threshold, which has been shown to further decrease CTPA use.⁶ This does not preclude the use of YEARS criteria; applying age-adjusted D-dimer thresholds would have led to an absolute reduction of 8.7% (95% CI, 6.4-11) in CTPAs.⁷

CHALLENGES TO IMPLEMENTATION

None to speak of

We see no challenges to the implementation of this recommendation.

ACKNOWLEDGEMENT

The PURLs Surveillance System was supported in part by Grant Number UL1RR024999 from the National Center For Research Resources, a Clinical Translational Science Award to the University of Chicago. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Center For Research Resources or the National Institutes of Health.

ILLUSTRATIVE CASE

Penny E is a 48-year-old woman with a history of asthma who presents with wheezing and respiratory distress. There are no clinical signs of deep vein thrombosis or hemoptysis. Pulmonary embolism (PE) is not your most likely diagnosis, but it is included in the differential, so you order a D-dimer concentration and it returns at 700 ng/mL. Should you order computed tomography pulmonary angiography (CTPA) to evaluate for PE?

PE is the third most common type of cardiovascular disease after coronary artery disease and stroke, with an estimated incidence in the United States of 1-2 people/1000 population and a 30-day mortality rate between 10% and 30%.² Improved adherence to a clinical decision support system has been shown to significantly decrease the number of diagnostic tests performed and the number of diagnostic failures.³

The use of a diagnostic algorithm that includes the Wells’ criteria and a D-dimer concentration can exclude PE without CTPA in 20% to 30% of patients.⁴ However, due to the complexity of the algorithm and insufficient time in busy emergency departments, adherence to recommended diagnostic strategies is variable.⁵

Further, it is common for a D-dimer test to be obtained before clinical assessment by a provider.⁶ A fixed cutoff D-dimer concentration of 500 ng/mL is commonly used despite an absolute reduction of 11.6% (95% confidence interval [CI], 10.5-12.9) in the need for CTPA using an age-adjusted D-dimer concentration threshold (age × 10 ng/mL for patients > 50 years).⁷

Three items of the original Wells’ criteria—clinical signs of deep vein thrombosis, hemoptysis, and whether PE is the most likely diagnosis—are the most predictive for PE.⁸ The development of a more efficient algorithm based on these 3 items that uses differential D-dimer concentration thresholds could retain sensitivity and decrease unnecessary CTPAs. Decreasing CTPAs would avoid contrast-induced nephropathy and decrease cancers associated with radiation exposure.^9-11 Significant cost savings could also be achieved, as the estimated cost of one CTPA is $648, while a D-dimer concentration is estimated to cost $14.¹²

STUDY SUMMARY

Simplified algorithm diagnoses PE with fewer CTPAs

The YEARS study was a prospective cohort study conducted in 12 hospitals in the Netherlands that included 3616 patients with clinically suspected PE.¹ After excluding 151 patients who met exclusion criteria (life expectancy < 3 months, ongoing anticoagulation treatment, pregnancy, and contraindication to CTPA), investigators managed 3465 study patients according to the YEARS algorithm. This algorithm called for obtaining a D-dimer concentration in all patients and assessment using the YEARS clinical decision rule, consisting of 3 items assessed by an attending physician: clinical signs of deep vein thrombosis, hemoptysis, and whether PE was the most likely diagnosis. PE was considered excluded if a patient had no positive YEARS items and a D-dimer concentration < 1000 ng/mL or if the patient had one or more YEARS items and a D-dimer concentration < 500 ng/mL. The primary outcome was venous thromboembolism (VTE) events at 3 months’ follow-up once PE was excluded. The secondary outcome was the number of required CTPAs using the YEARS decision rule compared with the number that would have been required if the Wells’ diagnostic algorithm had been implemented.

Of the 1743 patients who had none of the 3 YEARS items, 1320 had a D-dimer concentration below the 1000 ng/mL threshold. Fifty-five of the 423 who had a D-dimer ≥ 1000 ng/mL had confirmed PE by CTPA. In the 1722 patients who had at least 1 YEARS item, 1391 had a D-dimer concentration ≥ 500 ng/mL threshold; 401 of those 1391 had PE confirmed by CTPA.

Continue to: Eighteen of the 2964 patients...

Eighteen of the 2964 patients who had PE ruled out by the YEARS algorithm at baseline were found to have symptomatic VTE during the follow-up period (0.61%; 95% CI, 0.36-0.96), with 6 patients (0.20%; 95% CI, 0.07-0.44) sustaining a fatal PE. The 3-month incidence of VTE in patients who did not have CTPA was 0.43% (95% CI, 0.17-0.88), which is similar to the 0.34% (0.036-0.96) reported in a previous meta-analysis of the Wells’ rule algorithm.¹³ Overall, fatal PE occurred in 0.3% (95% CI, 0.12-0.78) of patients in the YEARS cohort vs 0.6% (0.4-1.1) in a meta-analysis of studies using standard algorithms.¹⁴

The new diagnostic algorithm reduced the use of CT pulmonary angiography by 14% and produced a cost savings of $309,096.

Using an intention-to-diagnose analysis, 1611 (46%) patients did not have a CTPA indicated by the YEARS algorithm compared with 1174 (34%) using the Wells’ algorithm, for an absolute difference of 13% (95% CI, 10-15) and estimated cost savings of $283,176 in this sample. The per-protocol analysis also had a decrease of CTPA examinations in favor of the YEARS algorithm, ruling out 1651 (48%) patients—a decrease of 14% (95% CI, 12-16) and an estimated savings of $309,096.

WHAT’S NEW

High-level evidence says 14% fewer CTPAs

The YEARS study provides a high level of evidence that a new, simple diagnostic algorithm can reliably and efficiently exclude PE and decrease the need for CTPA by 14% (absolute difference; 95% CI, 12-16) when compared with using the Wells’ rule and fixed D-dimer threshold of < 500 ng/mL.

CAVEATS

No adjusting D-dimer for age

The YEARS criteria does not consider an age-adjusted D-dimer threshold, which has been shown to further decrease CTPA use.⁶ This does not preclude the use of YEARS criteria; applying age-adjusted D-dimer thresholds would have led to an absolute reduction of 8.7% (95% CI, 6.4-11) in CTPAs.⁷

CHALLENGES TO IMPLEMENTATION

None to speak of

We see no challenges to the implementation of this recommendation.

ACKNOWLEDGEMENT

The PURLs Surveillance System was supported in part by Grant Number UL1RR024999 from the National Center For Research Resources, a Clinical Translational Science Award to the University of Chicago. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Center For Research Resources or the National Institutes of Health.

ILLUSTRATIVE CASE

Penny E is a 48-year-old woman with a history of asthma who presents with wheezing and respiratory distress. There are no clinical signs of deep vein thrombosis or hemoptysis. Pulmonary embolism (PE) is not your most likely diagnosis, but it is included in the differential, so you order a D-dimer concentration and it returns at 700 ng/mL. Should you order computed tomography pulmonary angiography (CTPA) to evaluate for PE?

PE is the third most common type of cardiovascular disease after coronary artery disease and stroke, with an estimated incidence in the United States of 1-2 people/1000 population and a 30-day mortality rate between 10% and 30%.² Improved adherence to a clinical decision support system has been shown to significantly decrease the number of diagnostic tests performed and the number of diagnostic failures.³

The use of a diagnostic algorithm that includes the Wells’ criteria and a D-dimer concentration can exclude PE without CTPA in 20% to 30% of patients.⁴ However, due to the complexity of the algorithm and insufficient time in busy emergency departments, adherence to recommended diagnostic strategies is variable.⁵

Further, it is common for a D-dimer test to be obtained before clinical assessment by a provider.⁶ A fixed cutoff D-dimer concentration of 500 ng/mL is commonly used despite an absolute reduction of 11.6% (95% confidence interval [CI], 10.5-12.9) in the need for CTPA using an age-adjusted D-dimer concentration threshold (age × 10 ng/mL for patients > 50 years).⁷

Three items of the original Wells’ criteria—clinical signs of deep vein thrombosis, hemoptysis, and whether PE is the most likely diagnosis—are the most predictive for PE.⁸ The development of a more efficient algorithm based on these 3 items that uses differential D-dimer concentration thresholds could retain sensitivity and decrease unnecessary CTPAs. Decreasing CTPAs would avoid contrast-induced nephropathy and decrease cancers associated with radiation exposure.^9-11 Significant cost savings could also be achieved, as the estimated cost of one CTPA is $648, while a D-dimer concentration is estimated to cost $14.¹²

STUDY SUMMARY

Simplified algorithm diagnoses PE with fewer CTPAs

The YEARS study was a prospective cohort study conducted in 12 hospitals in the Netherlands that included 3616 patients with clinically suspected PE.¹ After excluding 151 patients who met exclusion criteria (life expectancy < 3 months, ongoing anticoagulation treatment, pregnancy, and contraindication to CTPA), investigators managed 3465 study patients according to the YEARS algorithm. This algorithm called for obtaining a D-dimer concentration in all patients and assessment using the YEARS clinical decision rule, consisting of 3 items assessed by an attending physician: clinical signs of deep vein thrombosis, hemoptysis, and whether PE was the most likely diagnosis. PE was considered excluded if a patient had no positive YEARS items and a D-dimer concentration < 1000 ng/mL or if the patient had one or more YEARS items and a D-dimer concentration < 500 ng/mL. The primary outcome was venous thromboembolism (VTE) events at 3 months’ follow-up once PE was excluded. The secondary outcome was the number of required CTPAs using the YEARS decision rule compared with the number that would have been required if the Wells’ diagnostic algorithm had been implemented.

Of the 1743 patients who had none of the 3 YEARS items, 1320 had a D-dimer concentration below the 1000 ng/mL threshold. Fifty-five of the 423 who had a D-dimer ≥ 1000 ng/mL had confirmed PE by CTPA. In the 1722 patients who had at least 1 YEARS item, 1391 had a D-dimer concentration ≥ 500 ng/mL threshold; 401 of those 1391 had PE confirmed by CTPA.

Continue to: Eighteen of the 2964 patients...

Eighteen of the 2964 patients who had PE ruled out by the YEARS algorithm at baseline were found to have symptomatic VTE during the follow-up period (0.61%; 95% CI, 0.36-0.96), with 6 patients (0.20%; 95% CI, 0.07-0.44) sustaining a fatal PE. The 3-month incidence of VTE in patients who did not have CTPA was 0.43% (95% CI, 0.17-0.88), which is similar to the 0.34% (0.036-0.96) reported in a previous meta-analysis of the Wells’ rule algorithm.¹³ Overall, fatal PE occurred in 0.3% (95% CI, 0.12-0.78) of patients in the YEARS cohort vs 0.6% (0.4-1.1) in a meta-analysis of studies using standard algorithms.¹⁴

The new diagnostic algorithm reduced the use of CT pulmonary angiography by 14% and produced a cost savings of $309,096.

Using an intention-to-diagnose analysis, 1611 (46%) patients did not have a CTPA indicated by the YEARS algorithm compared with 1174 (34%) using the Wells’ algorithm, for an absolute difference of 13% (95% CI, 10-15) and estimated cost savings of $283,176 in this sample. The per-protocol analysis also had a decrease of CTPA examinations in favor of the YEARS algorithm, ruling out 1651 (48%) patients—a decrease of 14% (95% CI, 12-16) and an estimated savings of $309,096.

WHAT’S NEW

High-level evidence says 14% fewer CTPAs

The YEARS study provides a high level of evidence that a new, simple diagnostic algorithm can reliably and efficiently exclude PE and decrease the need for CTPA by 14% (absolute difference; 95% CI, 12-16) when compared with using the Wells’ rule and fixed D-dimer threshold of < 500 ng/mL.

CAVEATS

No adjusting D-dimer for age

The YEARS criteria does not consider an age-adjusted D-dimer threshold, which has been shown to further decrease CTPA use.⁶ This does not preclude the use of YEARS criteria; applying age-adjusted D-dimer thresholds would have led to an absolute reduction of 8.7% (95% CI, 6.4-11) in CTPAs.⁷

CHALLENGES TO IMPLEMENTATION

None to speak of

We see no challenges to the implementation of this recommendation.

ACKNOWLEDGEMENT

The PURLs Surveillance System was supported in part by Grant Number UL1RR024999 from the National Center For Research Resources, a Clinical Translational Science Award to the University of Chicago. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Center For Research Resources or the National Institutes of Health.

Interest in osteopathy continues to rise in this country. Currently, more than 20% of medical students in the United States are training to be osteopathic physicians.¹ In addition, the 2007 National Health Interview Survey found that spinal manipulation was among the most common complementary and alternative medicine (CAM) therapies used; with 8.6% of US adults reporting that they used it within the previous 12 months.²

With the growing number of DOs and the high utilization of osteopathic manipulative treatment (OMT), it is important for all physicians to understand the role OMT can play in the treatment of conditions ranging from low back pain to irritable bowel syndrome so that patients may be offered, or referred for, the treatment when appropriate.

To clarify when OMT may be most beneficial, we performed a literature review. Our findings are summarized here. But first, a word about osteopathic medicine and what OMT entails.

Osteopathic physicians view the body as a whole

According to the American Osteopathic Association, “the osteopathic philosophy of medicine sees an interrelated unity in all systems of the body, with each working with the other to heal in times of illness."³ This “whole-person approach to medicine” focuses on looking beyond symptoms alone to understand how lifestyle and environmental factors impact well-being.

As part of their education, DOs receive special training in the musculoskeletal system and in OMT. OMT is the process by which DOs use their hands to diagnose illness and injury and then mobilize a patient’s joints and soft tissues using techniques that include muscle activation, stretching, joint articulation, and gentle pressure to encourage the body’s natural tendency to heal itself.

These patients with low back pain will likely benefit

In the past, studies with small sample sizes, blinding issues, differing controls, and subjective outcome measurements have marred research efforts to demonstrate the effectiveness of OMT. More recently, researchers have attempted to minimize these issues, particularly when evaluating the efficacy of OMT for low back pain.

Meta-analyses show decreased pain and improved function in patients who received osteopathic manipulative treatment for low back pain.

In addition to increasing sample size, studies have compared OMT to usual care, to sham manipulation, and more recently to other manual modalities including ultrasound to equalize the subjective effects of interventions.⁴ With improved study designs, there has been increased awareness of the effectiveness of spinal manipulation by organizations that develop guidelines for the care of patients with low back pain. The most recent clinical practice guideline from the American College of Physicians includes spinal manipulation as a treatment modality that should be considered by clinicians for patients who have acute, subacute, or chronic low back pain.⁵

Chronic nonspecific low back pain. Looking at OMT vs other interventions for chronic nonspecific low back pain, a 2014 meta-analysis found moderate quality evidence for clinically relevant effects of OMT on low back pain and function. In 6 studies that evaluated 769 patients with chronic nonspecific low back pain, there was a significant difference in pain—equivalent to a 1.5-point improvement (mean difference [MD]= -14.93; 95% confidence interval [CI], -25.18 to -4.68)—in favor of OMT compared with controls, as measured on a 10-point visual analogue scale (VAS).⁶ In all of the studies in this meta-analysis, the treating examiner used clinical judgment to determine which manipulation techniques would be most appropriate for each patient—an approach that best represents "real-world" osteopathic practice.⁶

Acute and chronic nonspecific low back pain. Similarly, in the same 2014 meta-analysis, 1141 participants with acute and chronic nonspecific low back pain in 10 studies had the equivalent of 1.3 points more pain relief with OMT compared with controls (MD= -12.91; 95% CI, -20.00 to -5.82). The authors used the standardized mean difference (SMD), which is the difference in means divided by the standard deviation, to interpret the magnitude of difference in function between participants who received OMT and those in the control groups. Further, 1046 participants with acute and chronic nonspecific low back pain in 9 studies had a small improvement in functional status using the Roland-Morris Disability Questionnaire (RMDQ) or Oswestry-Disability Index (SMD= -0.36; 95% CI, -0.58 to -0.14).⁶

A 2005 meta-analysis that evaluated 6 randomized controlled trials (RCTs) involving 549 patients with low back pain found that 318 patients who received OMT had significantly less low back pain compared with 231 controls (effect size= -0.30; 95% CI, -0.47 to -0.13; P=.001).⁷ Although significant, an effect size of this magnitude is characterized as small.⁸

Other benefits of OMT include increased patient satisfaction, fewer meds

A randomized double-blind, sham-controlled study involving 455 patients with chronic low back pain compared outcomes of OMT to sham OMT applied in 6 treatment sessions over 8 weeks.⁹ Intention-to-treat analysis was performed to measure moderate and substantial improvements in low back pain at Week 12 (≥30% and ≥50% pain reductions from baseline, respectively). Based on the Cochrane Back Review Group criteria for effect sizes, response ratios were calculated to determine if the differences seen were considered clinically relevant.¹⁰

Patients receiving OMT were more likely to achieve moderate (response ratio=1.38; 95% CI, 1.16-1.64; P<.001) and substantial (response ratio=1.41; 95% CI, 1.13-1.76; P=.002) improvements in low back pain at Week 12. The calculated number needed to treat (NNT) for moderate and significant improvement in pain at 12 weeks was 6 and 7, respectively. In addition, patients in the OMT group were more likely to be very satisfied with their care (P<.001) with an NNT of 5, and used fewer medications than did patients in the sham group during the 12 weeks of the study (use ratio=0.66; 95% CI, 0.43-1.00; P=.048; NNT=15).⁹

Pregnant women may benefit from OMT in the third trimester

A 2013 RCT involving 144 patients randomized to OMT, sham ultrasound, or usual obstetric care found that 68 patients (47%) experienced back-specific dysfunction during their third trimester of pregnancy (defined by a ≥2-point increase in the RMDQ).¹¹

OMT reduced the risk of back-specific dysfunction by 40% vs the ultrasound group (relative risk [RR]=0.6; 95% CI, 0.3-1; P=.046) and 60% vs the usual obstetric care group (RR=0.4; 95% CI, 0.2-0.7; P<.001). The corresponding NNTs were 5.1 (95% CI, 2.7-282.2) for the OMT group vs the ultrasound group and 2.5 (95% CI, 1.8-4.9) vs the usual care group. The outcomes of this study were not conclusive because the initial RMDQ score was 1.8 points worse for the OMT group than for the usual care group.¹¹

Subsequently, the PROMOTE (Pregnancy Research on Osteopathic Manipulation Optimizing Treatment Effects) study involving 400 patients demonstrated that a standard OMT protocol was effective for decreasing pain and function deterioration compared with usual obstetric care.¹² However, results from the OMT group did not differ significantly from those of the ultrasound group, which were labeled as subtherapeutic in the study.¹²

The most recent Cochrane Review on low back pain in pregnancy noted that there was moderate quality evidence (due to study design limitations or imprecision) that OMT significantly reduced low back pain and function disability.¹³

OMT for other conditions? The evidence is limited

To date, studies on conditions other than low back pain have not demonstrated the same robust improvements in design as have those concerning low back pain (ie, larger sample sizes, comparisons to usual care and other treatments, etc.), and available data are not sufficiently significant to compel a change in clinical practice. Despite this, patients seek out, and receive, OMT as an alternative or adjunctive treatment for many conditions other than low back pain,² and family physicians should be aware of the current evidence for OMT in those conditions.

OMT for acute neck pain: A comparison with ketorolac

Researchers randomized 58 patients presenting to 3 emergency departments with neck pain of less than 3 weeks’ duration to receive either OMT or 30 mg IM ketorolac.¹⁴ OMT techniques were provided at the discretion of the physician based on patient needs. Patients rated their pain intensity on an 11-point numerical scale at the time of presentation and one hour after treatment. Patients receiving ketorolac or OMT had significant reductions in pain intensity with improvements of 1.7 +/- 1.6 (95% CI, 1.1-2.3; P<.001) and 2.8 +/- 1.7 (95% CI, 2.1-3.4; P<.001), respectively.

Patients who received osteopathic manipulative treatment for low back pain used fewer medications.

Although the pain reduction changes were statistically significant in both groups, the improvements were small enough to question if they were functionally significant. Compared to those receiving ketorolac, those receiving OMT reported a significantly greater decrease in their pain intensity (2.8 vs 1.7; 95% CI, 0.2-1.9; P=.02), but it’s worth noting that the dose of ketorolac was half the recommended dose for moderate or severe pain.¹⁴

Patients may have more headache-free days with OMT

To assess the use of OMT to treat chronic migraine, researchers conducted a prospective, single-blind RCT in which 105 chronic migraine sufferers (average of 22.5 migraine days/month) were split into 3 treatment groups: OMT plus medications, sham OMT plus medications, and medications alone.¹⁵

OMT led to fewer days with migraines compared with the medication group (MD= -21.06; 95% CI, -23.19 to -18.92; P<.001) and sham OMT group (MD= -17.43; 95% CI, -19.57 to -15.29; P<.001), resulting in less functional disability (P<.001).¹⁵ Caution should be taken in interpreting the results of this small trial, however, as an effect of this size has not been replicated in other studies.

A small (N=29) single-blind RCT looked at progressive muscular relaxation with and without OMT for the treatment of tension headache. Patients who completed relaxation exercises plus 3 sessions of OMT experienced significantly more headache-free days (1.79 vs 0.21; P=.016).¹⁶ Despite this finding, headache intensity and headache diary ratings were not different between the 2 groups in this study.

Postoperative OMT may decrease length of stay

In a retrospective study evaluating the effect of OMT on postoperative outcomes in 55 patients who underwent gastrointestinal surgery, a total of 17 patients who received a single OMT session within 48 hours of surgery had a mean time to flatus of 3.1 days compared with 4.7 days in the usual care control group (P=.035).¹⁷ The mean length of stay was 6.1 days in the OMT group and 11.5 days in the non-OMT group (P=.006).

Major limitations of this study include that it was retrospective in design and that only 17 of 55 patients had OMT performed, indicating a possible selection bias.

Pneumonia: OMT may reduce LOS and duration of antibiotic usage

The Multicenter Osteopathic Pneumonia Study in the Elderly (MOPSE), a double-blind RCT, looked at 406 patients ≥50 years hospitalized with pneumonia. Researchers randomized the group to receive either conventional care (CC; antibiotic treatment only), OMT and antibiotic therapy, or light-touch sham therapy with antibiotics.¹⁸ The researchers found no significant differences between the groups for any outcomes in the intention-to-treat analysis.

Patients who received osteopathic manipulative treatment for acute neck pain had greater pain relief than those who received a small dose of IM ketorolac.

In results obtained from the per protocol analysis, however, the median length of stay for those in the OMT group was 3.5 days, compared with 4.5 days for those in the CC group (95% CI, 3.2-4.0; P=.01). Multiple comparisons also indicated a reduction in mean duration of intravenous antibiotic use of 3 days in the OMT group (95% CI, 2.7-3.5) vs 3.5 days in the CC group (95% CI, 3.2-3.9). The treatment end-points of either death or respiratory failure occurred significantly less frequently in the OMT group compared with the CC group (P=.006).¹⁸

A Cochrane review of RCTs assessing the efficacy of adjunctive techniques compared with conventional therapy for patients with pneumonia revealed a reduction in hospital stay of 2 days (95% CI, -3.5 to -0.6) for patients who received OMT and positive expiratory pressure vs those who received neither intervention.¹⁹ Additionally, the duration of IV antibiotics and total duration of all (IV and oral) antibiotic treatment required in those treated adjunctively with OMT was shorter (MD for IV antibiotics= -2.1 days; 95% CI, -3.4 to -0.9 and MD for all antibiotics= -1.9 days; 95% CI, -3.1 to -0.7).¹⁹ The review was notable for a small sample size, with only 79 patients assessed.

OMT may improve IBS symptoms

A crossover study of 31 patients that compared visceral manipulation and sacral articulation OMT with sham therapy for the treatment of irritable bowel syndrome (IBS) demonstrated that OMT significantly decreased self-reported diarrhea (P=.016), abdominal distention (P=.043), abdominal pain (P=.013), and rectal sensitivity (P<.001), but did not significantly affect constipation.²⁰

In another study, researchers randomized 30 patients with IBS in a 2:1 distribution to OMT vs sham treatment.²¹ OMT included abdominal visceral techniques and direct and indirect spine techniques. All of the patients received 2 treatment sessions, and the researchers evaluated them at 7 and 28 days. At 7 days, both groups demonstrated a significant reduction in IBS symptoms, although the OMT group had significantly greater improvement (P=.01). At 28 days, however, neither group showed a significant reduction in symptoms.²¹

The lack of a control group (in the first study due to the crossover design), small sample sizes, and self-reported symptoms are major limitations to applying these studies to IBS treatment recommendations.

CORRESPONDENCE
Andrew H. Slattengren, DO, Broadway Family Medicine Clinic, 1020 West Broadway Avenue, Minneapolis, MN 55411; aslatten@umn.edu.

Interest in osteopathy continues to rise in this country. Currently, more than 20% of medical students in the United States are training to be osteopathic physicians.¹ In addition, the 2007 National Health Interview Survey found that spinal manipulation was among the most common complementary and alternative medicine (CAM) therapies used; with 8.6% of US adults reporting that they used it within the previous 12 months.²

With the growing number of DOs and the high utilization of osteopathic manipulative treatment (OMT), it is important for all physicians to understand the role OMT can play in the treatment of conditions ranging from low back pain to irritable bowel syndrome so that patients may be offered, or referred for, the treatment when appropriate.

To clarify when OMT may be most beneficial, we performed a literature review. Our findings are summarized here. But first, a word about osteopathic medicine and what OMT entails.

Osteopathic physicians view the body as a whole

According to the American Osteopathic Association, “the osteopathic philosophy of medicine sees an interrelated unity in all systems of the body, with each working with the other to heal in times of illness."³ This “whole-person approach to medicine” focuses on looking beyond symptoms alone to understand how lifestyle and environmental factors impact well-being.

As part of their education, DOs receive special training in the musculoskeletal system and in OMT. OMT is the process by which DOs use their hands to diagnose illness and injury and then mobilize a patient’s joints and soft tissues using techniques that include muscle activation, stretching, joint articulation, and gentle pressure to encourage the body’s natural tendency to heal itself.

These patients with low back pain will likely benefit

In the past, studies with small sample sizes, blinding issues, differing controls, and subjective outcome measurements have marred research efforts to demonstrate the effectiveness of OMT. More recently, researchers have attempted to minimize these issues, particularly when evaluating the efficacy of OMT for low back pain.

Meta-analyses show decreased pain and improved function in patients who received osteopathic manipulative treatment for low back pain.

In addition to increasing sample size, studies have compared OMT to usual care, to sham manipulation, and more recently to other manual modalities including ultrasound to equalize the subjective effects of interventions.⁴ With improved study designs, there has been increased awareness of the effectiveness of spinal manipulation by organizations that develop guidelines for the care of patients with low back pain. The most recent clinical practice guideline from the American College of Physicians includes spinal manipulation as a treatment modality that should be considered by clinicians for patients who have acute, subacute, or chronic low back pain.⁵

Chronic nonspecific low back pain. Looking at OMT vs other interventions for chronic nonspecific low back pain, a 2014 meta-analysis found moderate quality evidence for clinically relevant effects of OMT on low back pain and function. In 6 studies that evaluated 769 patients with chronic nonspecific low back pain, there was a significant difference in pain—equivalent to a 1.5-point improvement (mean difference [MD]= -14.93; 95% confidence interval [CI], -25.18 to -4.68)—in favor of OMT compared with controls, as measured on a 10-point visual analogue scale (VAS).⁶ In all of the studies in this meta-analysis, the treating examiner used clinical judgment to determine which manipulation techniques would be most appropriate for each patient—an approach that best represents "real-world" osteopathic practice.⁶

Acute and chronic nonspecific low back pain. Similarly, in the same 2014 meta-analysis, 1141 participants with acute and chronic nonspecific low back pain in 10 studies had the equivalent of 1.3 points more pain relief with OMT compared with controls (MD= -12.91; 95% CI, -20.00 to -5.82). The authors used the standardized mean difference (SMD), which is the difference in means divided by the standard deviation, to interpret the magnitude of difference in function between participants who received OMT and those in the control groups. Further, 1046 participants with acute and chronic nonspecific low back pain in 9 studies had a small improvement in functional status using the Roland-Morris Disability Questionnaire (RMDQ) or Oswestry-Disability Index (SMD= -0.36; 95% CI, -0.58 to -0.14).⁶

A 2005 meta-analysis that evaluated 6 randomized controlled trials (RCTs) involving 549 patients with low back pain found that 318 patients who received OMT had significantly less low back pain compared with 231 controls (effect size= -0.30; 95% CI, -0.47 to -0.13; P=.001).⁷ Although significant, an effect size of this magnitude is characterized as small.⁸

Other benefits of OMT include increased patient satisfaction, fewer meds

A randomized double-blind, sham-controlled study involving 455 patients with chronic low back pain compared outcomes of OMT to sham OMT applied in 6 treatment sessions over 8 weeks.⁹ Intention-to-treat analysis was performed to measure moderate and substantial improvements in low back pain at Week 12 (≥30% and ≥50% pain reductions from baseline, respectively). Based on the Cochrane Back Review Group criteria for effect sizes, response ratios were calculated to determine if the differences seen were considered clinically relevant.¹⁰

Patients receiving OMT were more likely to achieve moderate (response ratio=1.38; 95% CI, 1.16-1.64; P<.001) and substantial (response ratio=1.41; 95% CI, 1.13-1.76; P=.002) improvements in low back pain at Week 12. The calculated number needed to treat (NNT) for moderate and significant improvement in pain at 12 weeks was 6 and 7, respectively. In addition, patients in the OMT group were more likely to be very satisfied with their care (P<.001) with an NNT of 5, and used fewer medications than did patients in the sham group during the 12 weeks of the study (use ratio=0.66; 95% CI, 0.43-1.00; P=.048; NNT=15).⁹

Pregnant women may benefit from OMT in the third trimester

A 2013 RCT involving 144 patients randomized to OMT, sham ultrasound, or usual obstetric care found that 68 patients (47%) experienced back-specific dysfunction during their third trimester of pregnancy (defined by a ≥2-point increase in the RMDQ).¹¹

OMT reduced the risk of back-specific dysfunction by 40% vs the ultrasound group (relative risk [RR]=0.6; 95% CI, 0.3-1; P=.046) and 60% vs the usual obstetric care group (RR=0.4; 95% CI, 0.2-0.7; P<.001). The corresponding NNTs were 5.1 (95% CI, 2.7-282.2) for the OMT group vs the ultrasound group and 2.5 (95% CI, 1.8-4.9) vs the usual care group. The outcomes of this study were not conclusive because the initial RMDQ score was 1.8 points worse for the OMT group than for the usual care group.¹¹

Subsequently, the PROMOTE (Pregnancy Research on Osteopathic Manipulation Optimizing Treatment Effects) study involving 400 patients demonstrated that a standard OMT protocol was effective for decreasing pain and function deterioration compared with usual obstetric care.¹² However, results from the OMT group did not differ significantly from those of the ultrasound group, which were labeled as subtherapeutic in the study.¹²

The most recent Cochrane Review on low back pain in pregnancy noted that there was moderate quality evidence (due to study design limitations or imprecision) that OMT significantly reduced low back pain and function disability.¹³

OMT for other conditions? The evidence is limited

To date, studies on conditions other than low back pain have not demonstrated the same robust improvements in design as have those concerning low back pain (ie, larger sample sizes, comparisons to usual care and other treatments, etc.), and available data are not sufficiently significant to compel a change in clinical practice. Despite this, patients seek out, and receive, OMT as an alternative or adjunctive treatment for many conditions other than low back pain,² and family physicians should be aware of the current evidence for OMT in those conditions.

OMT for acute neck pain: A comparison with ketorolac

Researchers randomized 58 patients presenting to 3 emergency departments with neck pain of less than 3 weeks’ duration to receive either OMT or 30 mg IM ketorolac.¹⁴ OMT techniques were provided at the discretion of the physician based on patient needs. Patients rated their pain intensity on an 11-point numerical scale at the time of presentation and one hour after treatment. Patients receiving ketorolac or OMT had significant reductions in pain intensity with improvements of 1.7 +/- 1.6 (95% CI, 1.1-2.3; P<.001) and 2.8 +/- 1.7 (95% CI, 2.1-3.4; P<.001), respectively.

Patients who received osteopathic manipulative treatment for low back pain used fewer medications.

Although the pain reduction changes were statistically significant in both groups, the improvements were small enough to question if they were functionally significant. Compared to those receiving ketorolac, those receiving OMT reported a significantly greater decrease in their pain intensity (2.8 vs 1.7; 95% CI, 0.2-1.9; P=.02), but it’s worth noting that the dose of ketorolac was half the recommended dose for moderate or severe pain.¹⁴

Patients may have more headache-free days with OMT

To assess the use of OMT to treat chronic migraine, researchers conducted a prospective, single-blind RCT in which 105 chronic migraine sufferers (average of 22.5 migraine days/month) were split into 3 treatment groups: OMT plus medications, sham OMT plus medications, and medications alone.¹⁵

OMT led to fewer days with migraines compared with the medication group (MD= -21.06; 95% CI, -23.19 to -18.92; P<.001) and sham OMT group (MD= -17.43; 95% CI, -19.57 to -15.29; P<.001), resulting in less functional disability (P<.001).¹⁵ Caution should be taken in interpreting the results of this small trial, however, as an effect of this size has not been replicated in other studies.

A small (N=29) single-blind RCT looked at progressive muscular relaxation with and without OMT for the treatment of tension headache. Patients who completed relaxation exercises plus 3 sessions of OMT experienced significantly more headache-free days (1.79 vs 0.21; P=.016).¹⁶ Despite this finding, headache intensity and headache diary ratings were not different between the 2 groups in this study.

Postoperative OMT may decrease length of stay

In a retrospective study evaluating the effect of OMT on postoperative outcomes in 55 patients who underwent gastrointestinal surgery, a total of 17 patients who received a single OMT session within 48 hours of surgery had a mean time to flatus of 3.1 days compared with 4.7 days in the usual care control group (P=.035).¹⁷ The mean length of stay was 6.1 days in the OMT group and 11.5 days in the non-OMT group (P=.006).

Major limitations of this study include that it was retrospective in design and that only 17 of 55 patients had OMT performed, indicating a possible selection bias.

Pneumonia: OMT may reduce LOS and duration of antibiotic usage

The Multicenter Osteopathic Pneumonia Study in the Elderly (MOPSE), a double-blind RCT, looked at 406 patients ≥50 years hospitalized with pneumonia. Researchers randomized the group to receive either conventional care (CC; antibiotic treatment only), OMT and antibiotic therapy, or light-touch sham therapy with antibiotics.¹⁸ The researchers found no significant differences between the groups for any outcomes in the intention-to-treat analysis.

Patients who received osteopathic manipulative treatment for acute neck pain had greater pain relief than those who received a small dose of IM ketorolac.

In results obtained from the per protocol analysis, however, the median length of stay for those in the OMT group was 3.5 days, compared with 4.5 days for those in the CC group (95% CI, 3.2-4.0; P=.01). Multiple comparisons also indicated a reduction in mean duration of intravenous antibiotic use of 3 days in the OMT group (95% CI, 2.7-3.5) vs 3.5 days in the CC group (95% CI, 3.2-3.9). The treatment end-points of either death or respiratory failure occurred significantly less frequently in the OMT group compared with the CC group (P=.006).¹⁸

A Cochrane review of RCTs assessing the efficacy of adjunctive techniques compared with conventional therapy for patients with pneumonia revealed a reduction in hospital stay of 2 days (95% CI, -3.5 to -0.6) for patients who received OMT and positive expiratory pressure vs those who received neither intervention.¹⁹ Additionally, the duration of IV antibiotics and total duration of all (IV and oral) antibiotic treatment required in those treated adjunctively with OMT was shorter (MD for IV antibiotics= -2.1 days; 95% CI, -3.4 to -0.9 and MD for all antibiotics= -1.9 days; 95% CI, -3.1 to -0.7).¹⁹ The review was notable for a small sample size, with only 79 patients assessed.

OMT may improve IBS symptoms

A crossover study of 31 patients that compared visceral manipulation and sacral articulation OMT with sham therapy for the treatment of irritable bowel syndrome (IBS) demonstrated that OMT significantly decreased self-reported diarrhea (P=.016), abdominal distention (P=.043), abdominal pain (P=.013), and rectal sensitivity (P<.001), but did not significantly affect constipation.²⁰

In another study, researchers randomized 30 patients with IBS in a 2:1 distribution to OMT vs sham treatment.²¹ OMT included abdominal visceral techniques and direct and indirect spine techniques. All of the patients received 2 treatment sessions, and the researchers evaluated them at 7 and 28 days. At 7 days, both groups demonstrated a significant reduction in IBS symptoms, although the OMT group had significantly greater improvement (P=.01). At 28 days, however, neither group showed a significant reduction in symptoms.²¹

The lack of a control group (in the first study due to the crossover design), small sample sizes, and self-reported symptoms are major limitations to applying these studies to IBS treatment recommendations.

CORRESPONDENCE
Andrew H. Slattengren, DO, Broadway Family Medicine Clinic, 1020 West Broadway Avenue, Minneapolis, MN 55411; aslatten@umn.edu.

Interest in osteopathy continues to rise in this country. Currently, more than 20% of medical students in the United States are training to be osteopathic physicians.¹ In addition, the 2007 National Health Interview Survey found that spinal manipulation was among the most common complementary and alternative medicine (CAM) therapies used; with 8.6% of US adults reporting that they used it within the previous 12 months.²

With the growing number of DOs and the high utilization of osteopathic manipulative treatment (OMT), it is important for all physicians to understand the role OMT can play in the treatment of conditions ranging from low back pain to irritable bowel syndrome so that patients may be offered, or referred for, the treatment when appropriate.

To clarify when OMT may be most beneficial, we performed a literature review. Our findings are summarized here. But first, a word about osteopathic medicine and what OMT entails.

Osteopathic physicians view the body as a whole

According to the American Osteopathic Association, “the osteopathic philosophy of medicine sees an interrelated unity in all systems of the body, with each working with the other to heal in times of illness."³ This “whole-person approach to medicine” focuses on looking beyond symptoms alone to understand how lifestyle and environmental factors impact well-being.

As part of their education, DOs receive special training in the musculoskeletal system and in OMT. OMT is the process by which DOs use their hands to diagnose illness and injury and then mobilize a patient’s joints and soft tissues using techniques that include muscle activation, stretching, joint articulation, and gentle pressure to encourage the body’s natural tendency to heal itself.

These patients with low back pain will likely benefit

In the past, studies with small sample sizes, blinding issues, differing controls, and subjective outcome measurements have marred research efforts to demonstrate the effectiveness of OMT. More recently, researchers have attempted to minimize these issues, particularly when evaluating the efficacy of OMT for low back pain.

Meta-analyses show decreased pain and improved function in patients who received osteopathic manipulative treatment for low back pain.

In addition to increasing sample size, studies have compared OMT to usual care, to sham manipulation, and more recently to other manual modalities including ultrasound to equalize the subjective effects of interventions.⁴ With improved study designs, there has been increased awareness of the effectiveness of spinal manipulation by organizations that develop guidelines for the care of patients with low back pain. The most recent clinical practice guideline from the American College of Physicians includes spinal manipulation as a treatment modality that should be considered by clinicians for patients who have acute, subacute, or chronic low back pain.⁵

Chronic nonspecific low back pain. Looking at OMT vs other interventions for chronic nonspecific low back pain, a 2014 meta-analysis found moderate quality evidence for clinically relevant effects of OMT on low back pain and function. In 6 studies that evaluated 769 patients with chronic nonspecific low back pain, there was a significant difference in pain—equivalent to a 1.5-point improvement (mean difference [MD]= -14.93; 95% confidence interval [CI], -25.18 to -4.68)—in favor of OMT compared with controls, as measured on a 10-point visual analogue scale (VAS).⁶ In all of the studies in this meta-analysis, the treating examiner used clinical judgment to determine which manipulation techniques would be most appropriate for each patient—an approach that best represents "real-world" osteopathic practice.⁶

Acute and chronic nonspecific low back pain. Similarly, in the same 2014 meta-analysis, 1141 participants with acute and chronic nonspecific low back pain in 10 studies had the equivalent of 1.3 points more pain relief with OMT compared with controls (MD= -12.91; 95% CI, -20.00 to -5.82). The authors used the standardized mean difference (SMD), which is the difference in means divided by the standard deviation, to interpret the magnitude of difference in function between participants who received OMT and those in the control groups. Further, 1046 participants with acute and chronic nonspecific low back pain in 9 studies had a small improvement in functional status using the Roland-Morris Disability Questionnaire (RMDQ) or Oswestry-Disability Index (SMD= -0.36; 95% CI, -0.58 to -0.14).⁶

A 2005 meta-analysis that evaluated 6 randomized controlled trials (RCTs) involving 549 patients with low back pain found that 318 patients who received OMT had significantly less low back pain compared with 231 controls (effect size= -0.30; 95% CI, -0.47 to -0.13; P=.001).⁷ Although significant, an effect size of this magnitude is characterized as small.⁸

Other benefits of OMT include increased patient satisfaction, fewer meds

A randomized double-blind, sham-controlled study involving 455 patients with chronic low back pain compared outcomes of OMT to sham OMT applied in 6 treatment sessions over 8 weeks.⁹ Intention-to-treat analysis was performed to measure moderate and substantial improvements in low back pain at Week 12 (≥30% and ≥50% pain reductions from baseline, respectively). Based on the Cochrane Back Review Group criteria for effect sizes, response ratios were calculated to determine if the differences seen were considered clinically relevant.¹⁰

Patients receiving OMT were more likely to achieve moderate (response ratio=1.38; 95% CI, 1.16-1.64; P<.001) and substantial (response ratio=1.41; 95% CI, 1.13-1.76; P=.002) improvements in low back pain at Week 12. The calculated number needed to treat (NNT) for moderate and significant improvement in pain at 12 weeks was 6 and 7, respectively. In addition, patients in the OMT group were more likely to be very satisfied with their care (P<.001) with an NNT of 5, and used fewer medications than did patients in the sham group during the 12 weeks of the study (use ratio=0.66; 95% CI, 0.43-1.00; P=.048; NNT=15).⁹

Pregnant women may benefit from OMT in the third trimester

A 2013 RCT involving 144 patients randomized to OMT, sham ultrasound, or usual obstetric care found that 68 patients (47%) experienced back-specific dysfunction during their third trimester of pregnancy (defined by a ≥2-point increase in the RMDQ).¹¹

OMT reduced the risk of back-specific dysfunction by 40% vs the ultrasound group (relative risk [RR]=0.6; 95% CI, 0.3-1; P=.046) and 60% vs the usual obstetric care group (RR=0.4; 95% CI, 0.2-0.7; P<.001). The corresponding NNTs were 5.1 (95% CI, 2.7-282.2) for the OMT group vs the ultrasound group and 2.5 (95% CI, 1.8-4.9) vs the usual care group. The outcomes of this study were not conclusive because the initial RMDQ score was 1.8 points worse for the OMT group than for the usual care group.¹¹

Subsequently, the PROMOTE (Pregnancy Research on Osteopathic Manipulation Optimizing Treatment Effects) study involving 400 patients demonstrated that a standard OMT protocol was effective for decreasing pain and function deterioration compared with usual obstetric care.¹² However, results from the OMT group did not differ significantly from those of the ultrasound group, which were labeled as subtherapeutic in the study.¹²

The most recent Cochrane Review on low back pain in pregnancy noted that there was moderate quality evidence (due to study design limitations or imprecision) that OMT significantly reduced low back pain and function disability.¹³

OMT for other conditions? The evidence is limited

To date, studies on conditions other than low back pain have not demonstrated the same robust improvements in design as have those concerning low back pain (ie, larger sample sizes, comparisons to usual care and other treatments, etc.), and available data are not sufficiently significant to compel a change in clinical practice. Despite this, patients seek out, and receive, OMT as an alternative or adjunctive treatment for many conditions other than low back pain,² and family physicians should be aware of the current evidence for OMT in those conditions.

OMT for acute neck pain: A comparison with ketorolac

Researchers randomized 58 patients presenting to 3 emergency departments with neck pain of less than 3 weeks’ duration to receive either OMT or 30 mg IM ketorolac.¹⁴ OMT techniques were provided at the discretion of the physician based on patient needs. Patients rated their pain intensity on an 11-point numerical scale at the time of presentation and one hour after treatment. Patients receiving ketorolac or OMT had significant reductions in pain intensity with improvements of 1.7 +/- 1.6 (95% CI, 1.1-2.3; P<.001) and 2.8 +/- 1.7 (95% CI, 2.1-3.4; P<.001), respectively.

Patients who received osteopathic manipulative treatment for low back pain used fewer medications.

Although the pain reduction changes were statistically significant in both groups, the improvements were small enough to question if they were functionally significant. Compared to those receiving ketorolac, those receiving OMT reported a significantly greater decrease in their pain intensity (2.8 vs 1.7; 95% CI, 0.2-1.9; P=.02), but it’s worth noting that the dose of ketorolac was half the recommended dose for moderate or severe pain.¹⁴

Patients may have more headache-free days with OMT

To assess the use of OMT to treat chronic migraine, researchers conducted a prospective, single-blind RCT in which 105 chronic migraine sufferers (average of 22.5 migraine days/month) were split into 3 treatment groups: OMT plus medications, sham OMT plus medications, and medications alone.¹⁵

OMT led to fewer days with migraines compared with the medication group (MD= -21.06; 95% CI, -23.19 to -18.92; P<.001) and sham OMT group (MD= -17.43; 95% CI, -19.57 to -15.29; P<.001), resulting in less functional disability (P<.001).¹⁵ Caution should be taken in interpreting the results of this small trial, however, as an effect of this size has not been replicated in other studies.

A small (N=29) single-blind RCT looked at progressive muscular relaxation with and without OMT for the treatment of tension headache. Patients who completed relaxation exercises plus 3 sessions of OMT experienced significantly more headache-free days (1.79 vs 0.21; P=.016).¹⁶ Despite this finding, headache intensity and headache diary ratings were not different between the 2 groups in this study.

Postoperative OMT may decrease length of stay

In a retrospective study evaluating the effect of OMT on postoperative outcomes in 55 patients who underwent gastrointestinal surgery, a total of 17 patients who received a single OMT session within 48 hours of surgery had a mean time to flatus of 3.1 days compared with 4.7 days in the usual care control group (P=.035).¹⁷ The mean length of stay was 6.1 days in the OMT group and 11.5 days in the non-OMT group (P=.006).

Major limitations of this study include that it was retrospective in design and that only 17 of 55 patients had OMT performed, indicating a possible selection bias.

Pneumonia: OMT may reduce LOS and duration of antibiotic usage

The Multicenter Osteopathic Pneumonia Study in the Elderly (MOPSE), a double-blind RCT, looked at 406 patients ≥50 years hospitalized with pneumonia. Researchers randomized the group to receive either conventional care (CC; antibiotic treatment only), OMT and antibiotic therapy, or light-touch sham therapy with antibiotics.¹⁸ The researchers found no significant differences between the groups for any outcomes in the intention-to-treat analysis.

Patients who received osteopathic manipulative treatment for acute neck pain had greater pain relief than those who received a small dose of IM ketorolac.

In results obtained from the per protocol analysis, however, the median length of stay for those in the OMT group was 3.5 days, compared with 4.5 days for those in the CC group (95% CI, 3.2-4.0; P=.01). Multiple comparisons also indicated a reduction in mean duration of intravenous antibiotic use of 3 days in the OMT group (95% CI, 2.7-3.5) vs 3.5 days in the CC group (95% CI, 3.2-3.9). The treatment end-points of either death or respiratory failure occurred significantly less frequently in the OMT group compared with the CC group (P=.006).¹⁸

A Cochrane review of RCTs assessing the efficacy of adjunctive techniques compared with conventional therapy for patients with pneumonia revealed a reduction in hospital stay of 2 days (95% CI, -3.5 to -0.6) for patients who received OMT and positive expiratory pressure vs those who received neither intervention.¹⁹ Additionally, the duration of IV antibiotics and total duration of all (IV and oral) antibiotic treatment required in those treated adjunctively with OMT was shorter (MD for IV antibiotics= -2.1 days; 95% CI, -3.4 to -0.9 and MD for all antibiotics= -1.9 days; 95% CI, -3.1 to -0.7).¹⁹ The review was notable for a small sample size, with only 79 patients assessed.

OMT may improve IBS symptoms

A crossover study of 31 patients that compared visceral manipulation and sacral articulation OMT with sham therapy for the treatment of irritable bowel syndrome (IBS) demonstrated that OMT significantly decreased self-reported diarrhea (P=.016), abdominal distention (P=.043), abdominal pain (P=.013), and rectal sensitivity (P<.001), but did not significantly affect constipation.²⁰

In another study, researchers randomized 30 patients with IBS in a 2:1 distribution to OMT vs sham treatment.²¹ OMT included abdominal visceral techniques and direct and indirect spine techniques. All of the patients received 2 treatment sessions, and the researchers evaluated them at 7 and 28 days. At 7 days, both groups demonstrated a significant reduction in IBS symptoms, although the OMT group had significantly greater improvement (P=.01). At 28 days, however, neither group showed a significant reduction in symptoms.²¹

The lack of a control group (in the first study due to the crossover design), small sample sizes, and self-reported symptoms are major limitations to applying these studies to IBS treatment recommendations.

CORRESPONDENCE
Andrew H. Slattengren, DO, Broadway Family Medicine Clinic, 1020 West Broadway Avenue, Minneapolis, MN 55411; aslatten@umn.edu.

PRACTICE CHANGER
Do not prescribe tamsulosin or nifedipine for stone expulsion in patients with ureteral stones that are ≤ 10 mm.¹

Strength of recommendation
A: Based on a high-quality randomized controlled trial (RCT).¹

Bob Z, age 48, presents to the emergency department (ED) with unspecified groin pain. CT of the kidney, ureter, and bladder (CT KUB) finds evidence of a single ureteral stone measuring 8 mm. He’s prescribed medication for the pain and discharged. The day after his ED visit, he comes to your office to discuss further treatment options. Should you prescribe tamsulosin or nifedipine to help him pass the stone?

The most recent National Health and Nutrition Examination Survey found kidney stones affect 8.8% of the population.² Outpatient therapy is indicated for patients with ureteric colic secondary to stones ≤ 10 mm who do not have uncontrolled pain, impaired kidney function, or severe infection. Routine out­patient care includes oral hydration, antiemetics, and pain medications.

Medical expulsive therapy (MET) is also used to facilitate stone passage. MET is increasingly becoming part of routine care; use of MET in kidney stone patients in the United States has grown from 14% in 2009 to 64% in 2012.^3,4

The joint European Association of Urology/American Urological Association Nephrolithiasis Guideline Panel supports the use of MET.⁵ Meta-analyses of multiple RCTs suggest that an α-blocker (tamsulosin) or a calcium channel blocker (nifedipine) can reduce pain and lead to quicker stone passage and a higher rate of eventual stone passage when compared to placebo or observation.^6,7 However, these reviews included small, heterogeneous studies with a high or unclear risk for bias.

Continue for the study summary >>

STUDY SUMMARY
MET doesn’t increase the rate of stone passage
The SUSPEND (Spontaneous Urinary Stone Passage ENabled by Drugs) trial¹ was a multicenter RCT designed to determine the effectiveness of tamsulosin or nifedipine as MET for patients ages 18 to 65 with a single ureteric stone measuring ≤ 10 mm on CT KUB, which has 98% diagnostic accuracy.⁸ (Stones > 10 mm typically require surgery or lithotripsy.)

In this RCT, 1,167 adults were randomized to take tamsulosin (0.4 mg/d), nifedipine (30 mg/d), or placebo for four weeks or until the stone spontaneously passed, whichever came first. The participants, clinicians, and research staff were blinded to treatment assignment. The primary outcome was the proportion of participants who spontaneously passed their stone, as indicated in patient self-reported questionnaires and case-report forms completed by researchers. Secondary outcomes were time to stone passage and pain as assessed by analgesic use and a visual analogue scale (VAS).

At four weeks, 1,136 (97%) of the randomized participants had data available for analysis. The proportion of participants who passed their stone did not differ between MET and placebo; 80% of the placebo group (303 of 379 participants) passed the stone, compared with 81% (307 of 378) of the tamsulosin group and 80% (304 of 379) of the nifedipine group. The odds ratio (OR) for MET vs placebo was 1.04 (95% confidence interval [CI], 0.77 to 1.43) and the OR for tamsulosin vs nifedipine was 1.07 (95% CI, 0.74 to 1.53). These findings did not change with further subgroup analysis, including by sex, stone size (≤ 5 mm vs > 5 mm), or stone location.

There were no differences between groups in time to stone passage as measured by clinical report and confirmed by imaging. Time to passage of stone was available for 237 (21% of) participants. The mean days to stone passage was 15.9 (n = 84) for placebo, 16.5 (n = 79) for tamsulosin, and 16.2 (n = 74) for nifedipine, with a MET vs placebo difference of 0.5 days (95% CI, –2.9 to 3.9; P = .78). Sensitivity analysis accounting for bias from missing data did not change this outcome.

No differences in analgesic use or pain. Self-reported use of pain medication during the first four weeks was similar between groups: 59% (placebo patients), 56% (tamsulosin), and 56% (nifedipine). The mean days of pain medication use was 10.5 for placebo, 11.6 for tamsulosin, and 10.7 for nifedipine, with a MET vs placebo difference of 0.6 days (95% CI, –1.6 to 2.8; P = .45).

There was no difference between groups in the VAS pain score at four weeks. The MET vs placebo difference was 0.0 (95% CI, –0.4 to 0.4; P = .96) and the mean VAS pain score was 1.2 for placebo, 1.0 for tamsulosin, and 1.3 for nifedipine.

WHAT’S NEW
This large RCT contradicts results from previous meta-analyses
The SUSPEND study is the first large, multicenter RCT of MET with tamsulosin or nifedipine for kidney stones that used patient-oriented outcomes to find no benefit for stone expulsion, analgesic use, or reported pain compared to placebo. The discrepancy with prior meta-analyses is not unusual. Up to one-third of meta-analyses that show positive outcomes of a therapy are subsequently altered by the inclusion of results from a single, large, well-designed, multicenter RCT.⁹

Continue for caveats >>

CAVEATS
This trial included fewer women than previous studies
The SUSPEND study included a smaller proportion of women than previously published case series due to a need for a diagnostic CT KUB, which excluded more women than men due to radiation concerns. However, the proportion of women was balanced across all groups in this trial, and there was no evidence that sex impacted the efficacy of treatment for the primary outcome.¹

CHALLENGES TO IMPLEMENTATION
We see no challenges to the implementation of this recommendation.

References
1. Pickard R, Starr K, MacLennan G, et al. Medical expulsive therapy in adults with ureteric colic: a multicentre, randomised, placebo-controlled trial. Lancet. 2015;386:341-349.
2. Scales CD Jr, Smith AC, Hanley JM, et al. Prevalence of kidney stones in the United States. Eur Urol. 2012;62:160-165.
3. Fwu CW, Eggers PW, Kimmel PL, et al. Emergency department visits, use of imaging, and drugs for urolithiasis have increased in the United States. Kidney Int. 2013;89:479-486.
4. Bagga H, Appa A, Wang R, et al. 2257 medical expulsion therapy is underutilized in women presenting to an emergency department with acute urinary stone disease. J Urol. 2013; 189:e925-e926.
5. Preminger GM, Tiselius HG, Assimos DG, et al; American Urological Association Education and Research, Inc; European Association of Urology. 2007 Guideline for the management of ureteral calculi. Eur Urol. 2007;52:1610-1631.
6. Campschroer T, Zhu Y, Duijvesz D, et al. Alpha-blockers as medical expulsive therapy for ureteral stones. Cochrane Database Syst Rev. 2014;4:CD008509.
7. Seitz C, Liatsikos E, Porpiglia F, et al. Medical therapy to facilitate the passage of stones: what is the evidence? Eur Urol. 2009;56:455-471.
8. Worster A, Preyra I, Weaver B, et al. The accuracy of noncontrast helical computed tomography versus intravenous pyelography in the diagnosis of suspected acute urolithiasis: a meta-analysis. Ann Emerg Med. 2002;40: 280-286.
9. LeLorier J, Gregoire G, Benhaddad A, et al. Discrepancies between meta-analyses and subsequent large randomized, controlled trials. N Engl J Med. 1997;337:536-542.

ACKNOWLEDGEMENT
The PURLs Surveillance System was supported in part by Grant Number UL1RR024999 from the National Center For Research Resources, a Clinical Translational Science Award to the University of Chicago. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Center For Research Resources or the National Institutes of Health.

Copyright © 2016. The Family Physicians Inquiries Network. All rights reserved.

Reprinted with permission from the Family Physicians Inquiries Network and The Journal of Family Practice. 2016;65(2):118-120.

PRACTICE CHANGER
Do not prescribe tamsulosin or nifedipine for stone expulsion in patients with ureteral stones that are ≤ 10 mm.¹

Strength of recommendation
A: Based on a high-quality randomized controlled trial (RCT).¹

Bob Z, age 48, presents to the emergency department (ED) with unspecified groin pain. CT of the kidney, ureter, and bladder (CT KUB) finds evidence of a single ureteral stone measuring 8 mm. He’s prescribed medication for the pain and discharged. The day after his ED visit, he comes to your office to discuss further treatment options. Should you prescribe tamsulosin or nifedipine to help him pass the stone?

The most recent National Health and Nutrition Examination Survey found kidney stones affect 8.8% of the population.² Outpatient therapy is indicated for patients with ureteric colic secondary to stones ≤ 10 mm who do not have uncontrolled pain, impaired kidney function, or severe infection. Routine out­patient care includes oral hydration, antiemetics, and pain medications.

Medical expulsive therapy (MET) is also used to facilitate stone passage. MET is increasingly becoming part of routine care; use of MET in kidney stone patients in the United States has grown from 14% in 2009 to 64% in 2012.^3,4

The joint European Association of Urology/American Urological Association Nephrolithiasis Guideline Panel supports the use of MET.⁵ Meta-analyses of multiple RCTs suggest that an α-blocker (tamsulosin) or a calcium channel blocker (nifedipine) can reduce pain and lead to quicker stone passage and a higher rate of eventual stone passage when compared to placebo or observation.^6,7 However, these reviews included small, heterogeneous studies with a high or unclear risk for bias.

Continue for the study summary >>

STUDY SUMMARY
MET doesn’t increase the rate of stone passage
The SUSPEND (Spontaneous Urinary Stone Passage ENabled by Drugs) trial¹ was a multicenter RCT designed to determine the effectiveness of tamsulosin or nifedipine as MET for patients ages 18 to 65 with a single ureteric stone measuring ≤ 10 mm on CT KUB, which has 98% diagnostic accuracy.⁸ (Stones > 10 mm typically require surgery or lithotripsy.)

In this RCT, 1,167 adults were randomized to take tamsulosin (0.4 mg/d), nifedipine (30 mg/d), or placebo for four weeks or until the stone spontaneously passed, whichever came first. The participants, clinicians, and research staff were blinded to treatment assignment. The primary outcome was the proportion of participants who spontaneously passed their stone, as indicated in patient self-reported questionnaires and case-report forms completed by researchers. Secondary outcomes were time to stone passage and pain as assessed by analgesic use and a visual analogue scale (VAS).

At four weeks, 1,136 (97%) of the randomized participants had data available for analysis. The proportion of participants who passed their stone did not differ between MET and placebo; 80% of the placebo group (303 of 379 participants) passed the stone, compared with 81% (307 of 378) of the tamsulosin group and 80% (304 of 379) of the nifedipine group. The odds ratio (OR) for MET vs placebo was 1.04 (95% confidence interval [CI], 0.77 to 1.43) and the OR for tamsulosin vs nifedipine was 1.07 (95% CI, 0.74 to 1.53). These findings did not change with further subgroup analysis, including by sex, stone size (≤ 5 mm vs > 5 mm), or stone location.

There were no differences between groups in time to stone passage as measured by clinical report and confirmed by imaging. Time to passage of stone was available for 237 (21% of) participants. The mean days to stone passage was 15.9 (n = 84) for placebo, 16.5 (n = 79) for tamsulosin, and 16.2 (n = 74) for nifedipine, with a MET vs placebo difference of 0.5 days (95% CI, –2.9 to 3.9; P = .78). Sensitivity analysis accounting for bias from missing data did not change this outcome.

No differences in analgesic use or pain. Self-reported use of pain medication during the first four weeks was similar between groups: 59% (placebo patients), 56% (tamsulosin), and 56% (nifedipine). The mean days of pain medication use was 10.5 for placebo, 11.6 for tamsulosin, and 10.7 for nifedipine, with a MET vs placebo difference of 0.6 days (95% CI, –1.6 to 2.8; P = .45).

There was no difference between groups in the VAS pain score at four weeks. The MET vs placebo difference was 0.0 (95% CI, –0.4 to 0.4; P = .96) and the mean VAS pain score was 1.2 for placebo, 1.0 for tamsulosin, and 1.3 for nifedipine.

WHAT’S NEW
This large RCT contradicts results from previous meta-analyses
The SUSPEND study is the first large, multicenter RCT of MET with tamsulosin or nifedipine for kidney stones that used patient-oriented outcomes to find no benefit for stone expulsion, analgesic use, or reported pain compared to placebo. The discrepancy with prior meta-analyses is not unusual. Up to one-third of meta-analyses that show positive outcomes of a therapy are subsequently altered by the inclusion of results from a single, large, well-designed, multicenter RCT.⁹

Continue for caveats >>

CAVEATS
This trial included fewer women than previous studies
The SUSPEND study included a smaller proportion of women than previously published case series due to a need for a diagnostic CT KUB, which excluded more women than men due to radiation concerns. However, the proportion of women was balanced across all groups in this trial, and there was no evidence that sex impacted the efficacy of treatment for the primary outcome.¹

CHALLENGES TO IMPLEMENTATION
We see no challenges to the implementation of this recommendation.

References
1. Pickard R, Starr K, MacLennan G, et al. Medical expulsive therapy in adults with ureteric colic: a multicentre, randomised, placebo-controlled trial. Lancet. 2015;386:341-349.
2. Scales CD Jr, Smith AC, Hanley JM, et al. Prevalence of kidney stones in the United States. Eur Urol. 2012;62:160-165.
3. Fwu CW, Eggers PW, Kimmel PL, et al. Emergency department visits, use of imaging, and drugs for urolithiasis have increased in the United States. Kidney Int. 2013;89:479-486.
4. Bagga H, Appa A, Wang R, et al. 2257 medical expulsion therapy is underutilized in women presenting to an emergency department with acute urinary stone disease. J Urol. 2013; 189:e925-e926.
5. Preminger GM, Tiselius HG, Assimos DG, et al; American Urological Association Education and Research, Inc; European Association of Urology. 2007 Guideline for the management of ureteral calculi. Eur Urol. 2007;52:1610-1631.
6. Campschroer T, Zhu Y, Duijvesz D, et al. Alpha-blockers as medical expulsive therapy for ureteral stones. Cochrane Database Syst Rev. 2014;4:CD008509.
7. Seitz C, Liatsikos E, Porpiglia F, et al. Medical therapy to facilitate the passage of stones: what is the evidence? Eur Urol. 2009;56:455-471.
8. Worster A, Preyra I, Weaver B, et al. The accuracy of noncontrast helical computed tomography versus intravenous pyelography in the diagnosis of suspected acute urolithiasis: a meta-analysis. Ann Emerg Med. 2002;40: 280-286.
9. LeLorier J, Gregoire G, Benhaddad A, et al. Discrepancies between meta-analyses and subsequent large randomized, controlled trials. N Engl J Med. 1997;337:536-542.

ACKNOWLEDGEMENT
The PURLs Surveillance System was supported in part by Grant Number UL1RR024999 from the National Center For Research Resources, a Clinical Translational Science Award to the University of Chicago. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Center For Research Resources or the National Institutes of Health.

Copyright © 2016. The Family Physicians Inquiries Network. All rights reserved.

Reprinted with permission from the Family Physicians Inquiries Network and The Journal of Family Practice. 2016;65(2):118-120.

PRACTICE CHANGER
Do not prescribe tamsulosin or nifedipine for stone expulsion in patients with ureteral stones that are ≤ 10 mm.¹

Strength of recommendation
A: Based on a high-quality randomized controlled trial (RCT).¹

Bob Z, age 48, presents to the emergency department (ED) with unspecified groin pain. CT of the kidney, ureter, and bladder (CT KUB) finds evidence of a single ureteral stone measuring 8 mm. He’s prescribed medication for the pain and discharged. The day after his ED visit, he comes to your office to discuss further treatment options. Should you prescribe tamsulosin or nifedipine to help him pass the stone?

The most recent National Health and Nutrition Examination Survey found kidney stones affect 8.8% of the population.² Outpatient therapy is indicated for patients with ureteric colic secondary to stones ≤ 10 mm who do not have uncontrolled pain, impaired kidney function, or severe infection. Routine out­patient care includes oral hydration, antiemetics, and pain medications.

Medical expulsive therapy (MET) is also used to facilitate stone passage. MET is increasingly becoming part of routine care; use of MET in kidney stone patients in the United States has grown from 14% in 2009 to 64% in 2012.^3,4

The joint European Association of Urology/American Urological Association Nephrolithiasis Guideline Panel supports the use of MET.⁵ Meta-analyses of multiple RCTs suggest that an α-blocker (tamsulosin) or a calcium channel blocker (nifedipine) can reduce pain and lead to quicker stone passage and a higher rate of eventual stone passage when compared to placebo or observation.^6,7 However, these reviews included small, heterogeneous studies with a high or unclear risk for bias.

Continue for the study summary >>

STUDY SUMMARY
MET doesn’t increase the rate of stone passage
The SUSPEND (Spontaneous Urinary Stone Passage ENabled by Drugs) trial¹ was a multicenter RCT designed to determine the effectiveness of tamsulosin or nifedipine as MET for patients ages 18 to 65 with a single ureteric stone measuring ≤ 10 mm on CT KUB, which has 98% diagnostic accuracy.⁸ (Stones > 10 mm typically require surgery or lithotripsy.)

In this RCT, 1,167 adults were randomized to take tamsulosin (0.4 mg/d), nifedipine (30 mg/d), or placebo for four weeks or until the stone spontaneously passed, whichever came first. The participants, clinicians, and research staff were blinded to treatment assignment. The primary outcome was the proportion of participants who spontaneously passed their stone, as indicated in patient self-reported questionnaires and case-report forms completed by researchers. Secondary outcomes were time to stone passage and pain as assessed by analgesic use and a visual analogue scale (VAS).

At four weeks, 1,136 (97%) of the randomized participants had data available for analysis. The proportion of participants who passed their stone did not differ between MET and placebo; 80% of the placebo group (303 of 379 participants) passed the stone, compared with 81% (307 of 378) of the tamsulosin group and 80% (304 of 379) of the nifedipine group. The odds ratio (OR) for MET vs placebo was 1.04 (95% confidence interval [CI], 0.77 to 1.43) and the OR for tamsulosin vs nifedipine was 1.07 (95% CI, 0.74 to 1.53). These findings did not change with further subgroup analysis, including by sex, stone size (≤ 5 mm vs > 5 mm), or stone location.

There were no differences between groups in time to stone passage as measured by clinical report and confirmed by imaging. Time to passage of stone was available for 237 (21% of) participants. The mean days to stone passage was 15.9 (n = 84) for placebo, 16.5 (n = 79) for tamsulosin, and 16.2 (n = 74) for nifedipine, with a MET vs placebo difference of 0.5 days (95% CI, –2.9 to 3.9; P = .78). Sensitivity analysis accounting for bias from missing data did not change this outcome.

No differences in analgesic use or pain. Self-reported use of pain medication during the first four weeks was similar between groups: 59% (placebo patients), 56% (tamsulosin), and 56% (nifedipine). The mean days of pain medication use was 10.5 for placebo, 11.6 for tamsulosin, and 10.7 for nifedipine, with a MET vs placebo difference of 0.6 days (95% CI, –1.6 to 2.8; P = .45).

There was no difference between groups in the VAS pain score at four weeks. The MET vs placebo difference was 0.0 (95% CI, –0.4 to 0.4; P = .96) and the mean VAS pain score was 1.2 for placebo, 1.0 for tamsulosin, and 1.3 for nifedipine.

WHAT’S NEW
This large RCT contradicts results from previous meta-analyses
The SUSPEND study is the first large, multicenter RCT of MET with tamsulosin or nifedipine for kidney stones that used patient-oriented outcomes to find no benefit for stone expulsion, analgesic use, or reported pain compared to placebo. The discrepancy with prior meta-analyses is not unusual. Up to one-third of meta-analyses that show positive outcomes of a therapy are subsequently altered by the inclusion of results from a single, large, well-designed, multicenter RCT.⁹

Continue for caveats >>

CAVEATS
This trial included fewer women than previous studies
The SUSPEND study included a smaller proportion of women than previously published case series due to a need for a diagnostic CT KUB, which excluded more women than men due to radiation concerns. However, the proportion of women was balanced across all groups in this trial, and there was no evidence that sex impacted the efficacy of treatment for the primary outcome.¹

CHALLENGES TO IMPLEMENTATION
We see no challenges to the implementation of this recommendation.

References
1. Pickard R, Starr K, MacLennan G, et al. Medical expulsive therapy in adults with ureteric colic: a multicentre, randomised, placebo-controlled trial. Lancet. 2015;386:341-349.
2. Scales CD Jr, Smith AC, Hanley JM, et al. Prevalence of kidney stones in the United States. Eur Urol. 2012;62:160-165.
3. Fwu CW, Eggers PW, Kimmel PL, et al. Emergency department visits, use of imaging, and drugs for urolithiasis have increased in the United States. Kidney Int. 2013;89:479-486.
4. Bagga H, Appa A, Wang R, et al. 2257 medical expulsion therapy is underutilized in women presenting to an emergency department with acute urinary stone disease. J Urol. 2013; 189:e925-e926.
5. Preminger GM, Tiselius HG, Assimos DG, et al; American Urological Association Education and Research, Inc; European Association of Urology. 2007 Guideline for the management of ureteral calculi. Eur Urol. 2007;52:1610-1631.
6. Campschroer T, Zhu Y, Duijvesz D, et al. Alpha-blockers as medical expulsive therapy for ureteral stones. Cochrane Database Syst Rev. 2014;4:CD008509.
7. Seitz C, Liatsikos E, Porpiglia F, et al. Medical therapy to facilitate the passage of stones: what is the evidence? Eur Urol. 2009;56:455-471.
8. Worster A, Preyra I, Weaver B, et al. The accuracy of noncontrast helical computed tomography versus intravenous pyelography in the diagnosis of suspected acute urolithiasis: a meta-analysis. Ann Emerg Med. 2002;40: 280-286.
9. LeLorier J, Gregoire G, Benhaddad A, et al. Discrepancies between meta-analyses and subsequent large randomized, controlled trials. N Engl J Med. 1997;337:536-542.

ACKNOWLEDGEMENT
The PURLs Surveillance System was supported in part by Grant Number UL1RR024999 from the National Center For Research Resources, a Clinical Translational Science Award to the University of Chicago. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Center For Research Resources or the National Institutes of Health.

Copyright © 2016. The Family Physicians Inquiries Network. All rights reserved.

Reprinted with permission from the Family Physicians Inquiries Network and The Journal of Family Practice. 2016;65(2):118-120.

Illustrative case

Bob Z, age 48, presents to the emergency department (ED) with unspecified groin pain. A computed tomography scan of the kidney, ureter, and bladder (CT KUB) finds evidence of a single ureteral stone measuring 8 mm. He’s prescribed medication for the pain and discharged. The day after his ED visit, he comes to your office to discuss further treatment options. Should you prescribe tamsulosin or nifedipine to help him pass the stone?

The most recent National Health and Nutrition Examination Survey found kidney stones affect 8.8% of the population.² Outpatient therapy is indicated for patients with ureteric colic secondary to stones ≤10 mm who do not have uncontrolled pain, impaired kidney function, or severe infection. Routine outpatient care includes oral hydration, antiemetics, and pain medications. Medical expulsive therapy (MET) is also used to facilitate stone passage. MET is increasingly becoming part of routine care; use of MET in kidney stone patients in the United States has grown from 14% in 2009 to 64% in 2012.^3,4

The joint European Association of Urology/American Urological Association Nephrolithiasis Guideline Panel supports the use of MET.⁵ Meta-analyses of multiple randomized controlled trials (RCTs) suggest that an alpha-blocker (tamsulosin) or a calcium channel blocker (nifedipine) can reduce pain and lead to quicker stone passage and a higher rate of eventual stone passage when compared to placebo or observation.^6,7 However, these reviews included small, heterogeneous studies with a high or unclear risk of bias.

Treatment with tamsulosin or nifedipine provided no benefits in terms of rate of kidney stone passage, time to passage, analgesic use, or pain.

STUDY SUMMARY: MET doesn’t increase the rate of stone passage

The SUSPEND (Spontaneous Urinary Stone Passage ENabled by Drugs) trial¹ was a multicenter RCT designed to determine the effectiveness of tamsulosin or nifedipine as MET for patients ages 18 to 65 years with a single ureteric stone measuring ≤10 mm on CT KUB, which has 98% diagnostic accuracy.⁸ (Stones >10 mm typically require surgery or lithotripsy.)

In this RCT, 1167 adults were randomized to take tamsulosin 0.4 mg/d, nifedipine 30 mg/d, or placebo for 4 weeks or until the stone spontaneously passed, whichever came first. The participants, clinicians, and research staff were blinded to treatment assignment. The primary outcome was the proportion of participants who spontaneously passed their stone, as indicated in patient self-reported questionnaires and case-report forms completed by researchers. Secondary outcomes were time to stone passage and pain as assessed by analgesic use and a visual analogue scale (VAS).

At 4 weeks, 1136 (97%) of the randomized participants had data available for analysis. The proportion of participants who passed their stone did not differ between MET and placebo; 80% of the placebo group (303 of 379 participants) passed the stone, compared with 81% (307 of 378) of the tamsulosin group and 80% (304 of 379) of the nifedipine group. The odds ratio (OR) for MET vs placebo was 1.04 (95% confidence interval [CI], 0.77 to 1.43) and the OR for tamsulosin vs nifedipine was 1.07 (95% CI, 0.74 to 1.53). These findings did not change with further subgroup analysis, including by sex, stone size (≤5 mm vs >5 mm), or stone location.

There were no differences between groups in time to stone passage as measured by clinical report and confirmed by imaging. Time to passage of stone was available for 237 (21%) of participants. The mean days to stone passage was 15.9 (n=84) for placebo, 16.5 (n=79) for tamsulosin and 16.2 (n=74) for nifedipine, with a MET vs placebo difference of 0.5 days (95% CI, -2.9 to 3.9; P=.78). Sensitivity analysis accounting for bias from missing data did not change this outcome.

No differences in analgesic use or pain. Self-reported use of pain medication during the first 4 weeks was similar between groups: 59% (placebo patients), 56% (tamsulosin), and 56% (nifedipine). The mean days of pain medication use was 10.5 for placebo, 11.6 for tamsulosin, and 10.7 for nifedipine, with a MET vs placebo difference of 0.6 days (95% CI, -1.6 to 2.8; P=.45).

There was no difference between groups in the VAS pain score at 4 weeks. The MET vs placebo difference was 0.0 (95% CI, -0.4 to 0.4; P=.96) and the mean VAS pain score was 1.2 for placebo, 1.0 for tamsulosin, and 1.3 for nifedipine.

WHAT'S NEW: This large RCT contradicts results from previous meta-analyses

The SUSPEND study is the first large, multi­center RCT of MET with tamsulosin or nifedipine for kidney stones that used patient-oriented outcomes to find no benefit for stone expulsion, analgesic use, or reported pain compared to placebo. The discrepancy with prior meta-analyses is not unusual. Up to one-third of meta-analyses that show positive outcomes of a therapy are subsequently altered by the inclusion of results from a single, large, multicenter, well-designed RCT.⁹

CAVEATS: This trial included fewer women than previous studies

The SUSPEND study included a smaller proportion of women than previously published case series due to a need for a diagnostic CT KUB, which excluded more women than men due to radiation concerns. However, the proportion of women was balanced across all groups in this trial, and there was no evidence that sex impacted the efficacy of treatment for the primary outcome.¹

CHALLENGES TO IMPLEMENTATION

We see no challenges to the implementation of this recommendation.

ACKNOWLEDGEMENT
The PURLs Surveillance System was supported in part by Grant Number UL1RR024999 from the National Center For Research Resources, a Clinical Translational Science Award to the University of Chicago. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Center For Research Resources or the National Institutes of Health.

Click here to view PURL METHODOLOGY

Illustrative case

Bob Z, age 48, presents to the emergency department (ED) with unspecified groin pain. A computed tomography scan of the kidney, ureter, and bladder (CT KUB) finds evidence of a single ureteral stone measuring 8 mm. He’s prescribed medication for the pain and discharged. The day after his ED visit, he comes to your office to discuss further treatment options. Should you prescribe tamsulosin or nifedipine to help him pass the stone?

The most recent National Health and Nutrition Examination Survey found kidney stones affect 8.8% of the population.² Outpatient therapy is indicated for patients with ureteric colic secondary to stones ≤10 mm who do not have uncontrolled pain, impaired kidney function, or severe infection. Routine outpatient care includes oral hydration, antiemetics, and pain medications. Medical expulsive therapy (MET) is also used to facilitate stone passage. MET is increasingly becoming part of routine care; use of MET in kidney stone patients in the United States has grown from 14% in 2009 to 64% in 2012.^3,4

The joint European Association of Urology/American Urological Association Nephrolithiasis Guideline Panel supports the use of MET.⁵ Meta-analyses of multiple randomized controlled trials (RCTs) suggest that an alpha-blocker (tamsulosin) or a calcium channel blocker (nifedipine) can reduce pain and lead to quicker stone passage and a higher rate of eventual stone passage when compared to placebo or observation.^6,7 However, these reviews included small, heterogeneous studies with a high or unclear risk of bias.

Treatment with tamsulosin or nifedipine provided no benefits in terms of rate of kidney stone passage, time to passage, analgesic use, or pain.

STUDY SUMMARY: MET doesn’t increase the rate of stone passage

The SUSPEND (Spontaneous Urinary Stone Passage ENabled by Drugs) trial¹ was a multicenter RCT designed to determine the effectiveness of tamsulosin or nifedipine as MET for patients ages 18 to 65 years with a single ureteric stone measuring ≤10 mm on CT KUB, which has 98% diagnostic accuracy.⁸ (Stones >10 mm typically require surgery or lithotripsy.)

In this RCT, 1167 adults were randomized to take tamsulosin 0.4 mg/d, nifedipine 30 mg/d, or placebo for 4 weeks or until the stone spontaneously passed, whichever came first. The participants, clinicians, and research staff were blinded to treatment assignment. The primary outcome was the proportion of participants who spontaneously passed their stone, as indicated in patient self-reported questionnaires and case-report forms completed by researchers. Secondary outcomes were time to stone passage and pain as assessed by analgesic use and a visual analogue scale (VAS).

At 4 weeks, 1136 (97%) of the randomized participants had data available for analysis. The proportion of participants who passed their stone did not differ between MET and placebo; 80% of the placebo group (303 of 379 participants) passed the stone, compared with 81% (307 of 378) of the tamsulosin group and 80% (304 of 379) of the nifedipine group. The odds ratio (OR) for MET vs placebo was 1.04 (95% confidence interval [CI], 0.77 to 1.43) and the OR for tamsulosin vs nifedipine was 1.07 (95% CI, 0.74 to 1.53). These findings did not change with further subgroup analysis, including by sex, stone size (≤5 mm vs >5 mm), or stone location.

There were no differences between groups in time to stone passage as measured by clinical report and confirmed by imaging. Time to passage of stone was available for 237 (21%) of participants. The mean days to stone passage was 15.9 (n=84) for placebo, 16.5 (n=79) for tamsulosin and 16.2 (n=74) for nifedipine, with a MET vs placebo difference of 0.5 days (95% CI, -2.9 to 3.9; P=.78). Sensitivity analysis accounting for bias from missing data did not change this outcome.

No differences in analgesic use or pain. Self-reported use of pain medication during the first 4 weeks was similar between groups: 59% (placebo patients), 56% (tamsulosin), and 56% (nifedipine). The mean days of pain medication use was 10.5 for placebo, 11.6 for tamsulosin, and 10.7 for nifedipine, with a MET vs placebo difference of 0.6 days (95% CI, -1.6 to 2.8; P=.45).

There was no difference between groups in the VAS pain score at 4 weeks. The MET vs placebo difference was 0.0 (95% CI, -0.4 to 0.4; P=.96) and the mean VAS pain score was 1.2 for placebo, 1.0 for tamsulosin, and 1.3 for nifedipine.

WHAT'S NEW: This large RCT contradicts results from previous meta-analyses

The SUSPEND study is the first large, multi­center RCT of MET with tamsulosin or nifedipine for kidney stones that used patient-oriented outcomes to find no benefit for stone expulsion, analgesic use, or reported pain compared to placebo. The discrepancy with prior meta-analyses is not unusual. Up to one-third of meta-analyses that show positive outcomes of a therapy are subsequently altered by the inclusion of results from a single, large, multicenter, well-designed RCT.⁹

CAVEATS: This trial included fewer women than previous studies

The SUSPEND study included a smaller proportion of women than previously published case series due to a need for a diagnostic CT KUB, which excluded more women than men due to radiation concerns. However, the proportion of women was balanced across all groups in this trial, and there was no evidence that sex impacted the efficacy of treatment for the primary outcome.¹

CHALLENGES TO IMPLEMENTATION

We see no challenges to the implementation of this recommendation.

ACKNOWLEDGEMENT
The PURLs Surveillance System was supported in part by Grant Number UL1RR024999 from the National Center For Research Resources, a Clinical Translational Science Award to the University of Chicago. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Center For Research Resources or the National Institutes of Health.

Click here to view PURL METHODOLOGY

Illustrative case

Bob Z, age 48, presents to the emergency department (ED) with unspecified groin pain. A computed tomography scan of the kidney, ureter, and bladder (CT KUB) finds evidence of a single ureteral stone measuring 8 mm. He’s prescribed medication for the pain and discharged. The day after his ED visit, he comes to your office to discuss further treatment options. Should you prescribe tamsulosin or nifedipine to help him pass the stone?

The most recent National Health and Nutrition Examination Survey found kidney stones affect 8.8% of the population.² Outpatient therapy is indicated for patients with ureteric colic secondary to stones ≤10 mm who do not have uncontrolled pain, impaired kidney function, or severe infection. Routine outpatient care includes oral hydration, antiemetics, and pain medications. Medical expulsive therapy (MET) is also used to facilitate stone passage. MET is increasingly becoming part of routine care; use of MET in kidney stone patients in the United States has grown from 14% in 2009 to 64% in 2012.^3,4

The joint European Association of Urology/American Urological Association Nephrolithiasis Guideline Panel supports the use of MET.⁵ Meta-analyses of multiple randomized controlled trials (RCTs) suggest that an alpha-blocker (tamsulosin) or a calcium channel blocker (nifedipine) can reduce pain and lead to quicker stone passage and a higher rate of eventual stone passage when compared to placebo or observation.^6,7 However, these reviews included small, heterogeneous studies with a high or unclear risk of bias.

Treatment with tamsulosin or nifedipine provided no benefits in terms of rate of kidney stone passage, time to passage, analgesic use, or pain.

STUDY SUMMARY: MET doesn’t increase the rate of stone passage

The SUSPEND (Spontaneous Urinary Stone Passage ENabled by Drugs) trial¹ was a multicenter RCT designed to determine the effectiveness of tamsulosin or nifedipine as MET for patients ages 18 to 65 years with a single ureteric stone measuring ≤10 mm on CT KUB, which has 98% diagnostic accuracy.⁸ (Stones >10 mm typically require surgery or lithotripsy.)

In this RCT, 1167 adults were randomized to take tamsulosin 0.4 mg/d, nifedipine 30 mg/d, or placebo for 4 weeks or until the stone spontaneously passed, whichever came first. The participants, clinicians, and research staff were blinded to treatment assignment. The primary outcome was the proportion of participants who spontaneously passed their stone, as indicated in patient self-reported questionnaires and case-report forms completed by researchers. Secondary outcomes were time to stone passage and pain as assessed by analgesic use and a visual analogue scale (VAS).

At 4 weeks, 1136 (97%) of the randomized participants had data available for analysis. The proportion of participants who passed their stone did not differ between MET and placebo; 80% of the placebo group (303 of 379 participants) passed the stone, compared with 81% (307 of 378) of the tamsulosin group and 80% (304 of 379) of the nifedipine group. The odds ratio (OR) for MET vs placebo was 1.04 (95% confidence interval [CI], 0.77 to 1.43) and the OR for tamsulosin vs nifedipine was 1.07 (95% CI, 0.74 to 1.53). These findings did not change with further subgroup analysis, including by sex, stone size (≤5 mm vs >5 mm), or stone location.

There were no differences between groups in time to stone passage as measured by clinical report and confirmed by imaging. Time to passage of stone was available for 237 (21%) of participants. The mean days to stone passage was 15.9 (n=84) for placebo, 16.5 (n=79) for tamsulosin and 16.2 (n=74) for nifedipine, with a MET vs placebo difference of 0.5 days (95% CI, -2.9 to 3.9; P=.78). Sensitivity analysis accounting for bias from missing data did not change this outcome.

No differences in analgesic use or pain. Self-reported use of pain medication during the first 4 weeks was similar between groups: 59% (placebo patients), 56% (tamsulosin), and 56% (nifedipine). The mean days of pain medication use was 10.5 for placebo, 11.6 for tamsulosin, and 10.7 for nifedipine, with a MET vs placebo difference of 0.6 days (95% CI, -1.6 to 2.8; P=.45).

There was no difference between groups in the VAS pain score at 4 weeks. The MET vs placebo difference was 0.0 (95% CI, -0.4 to 0.4; P=.96) and the mean VAS pain score was 1.2 for placebo, 1.0 for tamsulosin, and 1.3 for nifedipine.

WHAT'S NEW: This large RCT contradicts results from previous meta-analyses

The SUSPEND study is the first large, multi­center RCT of MET with tamsulosin or nifedipine for kidney stones that used patient-oriented outcomes to find no benefit for stone expulsion, analgesic use, or reported pain compared to placebo. The discrepancy with prior meta-analyses is not unusual. Up to one-third of meta-analyses that show positive outcomes of a therapy are subsequently altered by the inclusion of results from a single, large, multicenter, well-designed RCT.⁹

CAVEATS: This trial included fewer women than previous studies

The SUSPEND study included a smaller proportion of women than previously published case series due to a need for a diagnostic CT KUB, which excluded more women than men due to radiation concerns. However, the proportion of women was balanced across all groups in this trial, and there was no evidence that sex impacted the efficacy of treatment for the primary outcome.¹

CHALLENGES TO IMPLEMENTATION

We see no challenges to the implementation of this recommendation.

ACKNOWLEDGEMENT
The PURLs Surveillance System was supported in part by Grant Number UL1RR024999 from the National Center For Research Resources, a Clinical Translational Science Award to the University of Chicago. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Center For Research Resources or the National Institutes of Health.

Click here to view PURL METHODOLOGY