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1. Dexter PR, Perkins SM, Mahany KS, Jones K, McDonald CJ. Inpatient computer-based standing orders vs. physician reminders to increase influenza and pneumococcal vaccination rates: a randomized trial. JAMA. 2004; 292: 2366-71.

Past studies have suggested that most patients admitted with severe pneumococcal infections have been hospitalized in the preceding 5 years, and simply being hospitalized is a potential risk factor for later pneumococcal infection. Likewise, hospitalization provides an opportunity to vaccinate high-risk patients against influenza, and raising pneumococcal and influenza immunization rates is a CMS quality improvement priority. Prior investigations have supported the use of labor-intensive manual standing orders as well as computerized reminders, but this prospective trial was conducted in 1998 and 1999 to assess the effectiveness of a computer-based system to screen for eligible patients and then generate orders to perform pneumonia and influenza vaccinations on inpatients at the time of discharge.

Over 13 months, a total of 3777 inpatients were entered into the study. The hospital computer identified patients eligible for vaccination based on common criteria and randomized them to one of two groups of physician teams. For one group of teams, the computer order-entry system would automatically generate vaccination orders at the time of discharge for vaccine-eligible patients; for the other group of teams, only computer reminders were provided to physicians. The outcome measure was administration of vaccine; long-term outcomes such as incidence of subsequent disease or mortality were not measured.

During the study period, 50% of all hospitalized patients were identified as eligible for influenza vaccination; 22% were eligible for pneumococcal vaccination. In each case, the “standing order” group received vaccine more often (influenza: 42% vs. 30%, p<.001; pneumococcal vaccine: 51% vs. 31%). The numbers were subsequently adjusted to allow for patients who had previously received vaccine, but the impressive differences persisted. Nurses reported reasons for non-administration in 98% of the eligible patients who were not vaccinated; the most common reason was patient refusal. It is not clear if the physicians knew that a study was being conducted. No adverse reactions were reported.

CMS has pushed for the development of institutional standing order sets as a tool to improve compliance with vaccination rate targets. Where the technology is available, computer systems that can screen eligible patients and generate automatic orders are an effective tool in implementing many quality-improvement initiatives, and hospitalists are in a crucial position to take an active role in their development and implementation.

2. Fang MC, Chang Y, Hylek EM, et al. Advanced age, anticoagulation intensity, and risk for intracranial hemorrhage among patients taking warfarin for a trial fibrillation. Ann Intern Med. 2004; 141: 745-52.

Warfarin has been shown to reduce risk of stroke in patients with chronic and paroxysmal atrial fibrillation. Intracranial hemorrhage remains one of the most feared complications of warfarin, especially among older patients, prompting suggestions to consider lower intensity anticoagulation among patients older than 75 years who have atrial fibrillation.

This study evaluated the relationship between the intensity of anticoagulation, risk of intracranial hemorrhage, and age of patients with atrial fibrillation.

This was a retrospective case control study conducted at a tertiary care medical center. One-hundred and seventy patients on warfarin and admitted with intracranial hemorrhage from 1993 to 2002 were matched with 1020 patients who were on warfarin but without intracranial bleed. After controlling for comorbid conditions and aspirin use, authors conducted multivariable logistic regression analysis to determine the odds of intracranial hemorrhage with regard to age and INR. The risk of intracranial hemorrhage increased at 85 years of age and at INR values of 3.5 or greater. The risk of intracranial hemorrhage at INR less than 2.0 did not differ statistically from the risk at INR of 2.0–3.0.

 

 

This study shows the risk of intracranial hemorrhage is not decreased by choosing lower intensity anticoagulation, and target INR should still be kept at 2.5 among elderly patients. However, patients older than 85 years should be counseled about their higher risk of intracranial hemorrhage.

3. Heeschen C, Hamm CW, Mitrovic V, et al. N-terminal pro-B-type natriuretic peptide levels for dynamic risk stratification of patients with acute coronary syndromes. Circulation. 2004;110: 3206-12.

Recent data demonstrate the prognostic value of assessment of neurohormonal activation in patients with acute coronary syndromes (ACS). B-type natriuretic peptide levels (BNP) and levels of the N-terminal fragment of the BNP prohormone (NT-proBNP) predict adverse long-term outcomes in patients with ACS. Investigators reviewed plasma samples of Troponin T (TnT) and NT-proBNP obtained from patients with ACS enrolled in the Platelet Receptor Inhibition in Ischemic Syndrome Management (PRISM) trial, which randomized patients to tirofiban or heparin for 48 hours and assessed mortality and myocardial infarction at 30 day follow-up. TnT and NT-proBNP determinations were available at baseline for 1791 patients, and at 48 and 72 hours from 1401 patients. Baseline NT-proBNP levels >250 ng/L were associated with significantly higher rates of death and myocardial infarction at 7 and 30 day follow-up. After adjustment for TnT and C-reactive protein levels, elevated NTproBNP levels maintained its predictive value (OR 2.7; p<.001). In patients with normal TnT levels, NT-proBNP levels identified a subgroup of patients at increased risk (OR 3.0; p=.004). However, in patients with high TnT levels (>0.1 mcg/L), NT-proBNP lost its predictive value (p=.58). More importantly, patients with normal levels of both TnT and NT-proBNP were at very low risk (0.6% event rate at 30 day follow-up).

Serial determinations of NT-proBNP levels at 48 and 72 hours were reviewed in patients without major adverse cardiac events (death or myocardial infarction); these patients were subdivided into groups with and without refractory ischemia. Patients without refractory ischemia showed a significant decline in NT-proBNP levels, whereas patients with refractory ischemia had no significant change. Persistently elevated NT-proBNP levels at 72 hours were associated with a 17.2% risk of death or MI at 30 days, compared with 0.6% risk if NT-proBNP returned to normal at 72 hours (p<.001). Neither TnT nor C-reactive protein demonstrated similar predictive value.

The study is limited by its retrospective nature, by potential selection bias by including only patients with direct evidence of coronary artery disease, and by limitations of the generalizability of its findings (e.g., to emergency department patients with chest pain).

As BNP and NT-proBNP are counter-regulatory hormones that play an active role in the response to ischemic injury, the authors suggest that NT-proBNP is a promising tool for dynamic risk assessment in patients with ACS. The authors also do not differentiate between BNP and NT-proBNP with regard to use in risk stratification, which might lead one to believe that these tests share similar predictive value. (Of note, the study was entirely funded by a company that produces an assay for NT-proBNP). Prospective trials to validate this tool are warranted

4. Heuschmann PU, Kolominsky-Rabas PL, Roether J, et al. Predictors of in-hospital mortality in patients with acute ischemic stroke treated with thrombolytic therapy. JAMA. 2004;292:1831-38.

The objective of this study was to identify factors associated with in-hospital mortality in ischemic stroke patients treated with recombinant tissue plasminogen activator (tPA). It was a prospective observational cohort study of 1658 patients conducted at 225 community and academic hospitals throughout Germany with main outcome of in-hospital mortality.

In this study 10% of patients who were treated with tPA died during their hospital stay, with 2/3 of deaths occurring in the first 7 days. Relative probability of in-hospital mortality increased with increasing patient age, with an odds ratio (OR) of 1.6 for each 10-year increment in age. Age was an independent predictor of in hospital mortality irrespective of tPA administration, with patients older than 75 years age having 4 fold higher mortality than the youngest cohort of less than 55 years age.

 

 

Other factors predicting in hospital mortality were altered level of consciousness and relative lack of experience with tPA treatment in the center. Altered level of consciousness was a predictor of stroke severity and an independent predictor of in-hospital mortality (OR 3.4). The increase in mortality in centers with limited experience with tPA administration (OR 0.97) reflected learning curve issues with these patients. The study was not designed to separate out the confounders of operator experience curve from institutional experience curves, or to derive the exact relationship between experience and outcomes.

5. McAlister FA, Bertsch K, Man J, et al. Incidence of and risk factors for pulmonary complications after non-thoracic surgery. Am J Respir Crit Care Med. 2004; published ahead of print on November 24, 2004 as doi:10.1164/rccm.200408-1069OC. Accessed January 27, 2005.

Postoperative pulmonary complications after nonthoracic surgery are a cause of significant morbidity and increased length of hospital stay. Previous studies of preoperative pulmonary assessment were limited by non-representative patient samples, conflicting results, and lack of explicit definitions of these complications. The authors conducted a prospective cohort study of 1055 patients seen in a Pre-Admission Clinic of a tertiary care university hospital. Mean age was 55 years, 50% male, and the cohort consisted of patients scheduled for intermediate risk elective surgery (upper abdominal, lower abdominal, orthopedic). They evaluated physical exam maneuvers (cough test, wheeze test, maximal laryngeal height, and forced expiratory time, all of which are described in an online data supplement) and preoperative spirometry values, and collected information on clinically significant postoperative pulmonary complications, including pneumonia, respiratory failure requiring mechanical ventilation, atelectasis requiring bronchoscopy, or pneumothorax or pleural effusion requiring percutaneous intervention. Twenty-eight patients (2.7%) suffered a pulmonary complication within 7 days of surgery, one of whom died. Length of stay was significantly prolonged in this group (mean 27.9 days vs 4.5 days, p=.006). Multivariate regression analysis revealed four variables that were independently associated with increased risk for postoperative pulmonary complications: age > 65 years, positive cough test (repeated coughing after asking the patient to inhale deeply and cough once), perioperative nasogastric tube, and anesthesia duration 2.5 hours or greater. Number of pack years smoked, FEV1, FEV1/FVC ratio, and upper abdominal surgery were associated with postoperative pulmonary complications but were not found to be independently associated by multivariate analysis.

While it is not surprising that the above risk factors are predictive of postoperative complications, this is the first study to incorporate specific exam maneuvers and spirometry into a risk prediction analysis. Limitations of this model are lack of independent validation and lack of generalizability to other populations, e.g., inpatients awaiting urgent surgery. Of note, the study further provides further support for not routinely obtaining pulmonary function testing for risk stratification prior to noncardiac surgery.

6. Mortenson, EM, Restrepo M, Anzeuto A, Pugh J. Effects of guideline-concordant antimicrobial therapy on mortality among patients with community-acquired pneumonia. Am J Med. 2004;117:726-31.

The American Thoracic Society (ATS) and the Infectious Diseases Society of America (IDSA) have published guidelines for the management of community acquired pneumonia that include recommendations for antibiotic selection. This retrospective cohort study attempted to measure the association between adherence to such guidelines and 30-day mortality in patients admitted with pneumonia to two Texas hospitals.

The characteristics of the patients studied reflect a reasonable cross-section of typical pneumonia patients, with the exception that the patients were mostly (85%) men. Of the study population, 78% were admitted through the ER, 20% admitted to the ICU, and 9% were nursing home residents. Antibiotics were considered “concordant” if they were consistent with either the most recent IDSA or ATS recommendations. The “nonconcordant” group was slightly older (66 vs. 61), generally sicker (higher rate of comorbid COPD and CVD), had more cerebrovascular disease, was more likely to present with altered mental status, and less frequently received antibiotics within 8 hours of presentation. The study did not comment on patients’ vaccination status. Thirty-day mortality was 6.2% in the guideline-concordant group, versus 21.7% in the other group (p < .001). The most common “non-concordant” regimen described was use of a beta-lactam alone, although specific antibiotic regimens were not evaluated.

 

 

While the results of this study are not surprising, they provide us with both the validation to continue practice according to existing recommendations, particularly the avoidance of monotherapy with beta-lactam antibiotics. The study also provides us with the imperative to take the lead in developing evidence-based pneumonia pathways at our own hospitals.

7. Pham MX, Whooley MA, Evans GT Jr, et al. Prognostic value of low-level cardiac troponin-I elevations in patients without definite acute coronary syndromes. Am Heart J. 2004;148: 776-82.

With the availability of rapid and highly sensitive and specific troponin testing, many patients admitted to the hospital with non-cardiac diagnoses have been recognized as having abnormal serum troponin-I or troponin-T levels, often just slightly above the reference cutoff for “normal.” While the clinical assumption is often that the elevated enzyme level does not reflect an acute coronary syndrome per se, its significance regarding the patient’s underlying cardiac health is often unclear.

Pham et al. retrospectively reviewed the 1-year mortality of 366 patients who were admitted to the San Francisco VA without evidence of acute MI or ACS either clinically or by EKG, but who had low-level troponin-I elevations (up to 3.0 ng/mL—a level that the authors state was reached by institutional consensus, and which was measured by a “first-generation” assay). These patients were admitted for a broad spectrum of diagnoses ranging from CHF to COPD to sepsis. Ninety-six percent of the patients were men; their average age was 69.

Follow-up was accomplished after a mean of 288 days and included 97% of patients. The primary endpoint was MI or death due to cardiac disease at one year; secondary endpoints were revascularization or admission for unstable angina. The primary endpoint was reached by 11% of patients with cTn-I between 1.0 and 3.0 ng/mL, and 4% of the patients with cTn-I up to 1.0 ng/mL (adjusted HR 3.4, 95% CI, 1.3 to 9.4), and the higher the cTn-I, the higher the risk. However, the authors did not test for the level of risk by specific diagnosis, so they caution against overgeneralizing their findings.

The findings of this study add to the evidence that any evidence of myocardial injury implies an increased risk of underlying heart disease and accompanying long—term cardiac complications– even if such injury occurs in the absence of ACS or known heart disease. Hospitalists often see such injury in the setting of acute infection and pulmonary disease and may be the first to recognize the possibility of CHD in a given patient. To date, guidelines addressing optimal prospective risk stratification have not been developed. Until they are, hospitalists should be aware of the ramifications of “troponin leak” and be prepared to initiate necessary inpatient monitoring and treatments, and to coordinate appropriate follow-up for these patients.

8. Saposnik G, Young B, Silver B, et al. Lack of improvement in patients with acute stroke after treatment with thrombolytic therapy: predictors and association with outcome. JAMA. 2004; 292: 1839-44.

Recombinant tissue plasminogen activator (tPA) has been shown to be one of the most efficacious therapies for acute stroke treatment. This was a systematic evaluation of predictors for outcomes at 24 hours after tPA therapy and of the prognostic significance of lack of improvement at 24 hours for long-term outcomes at 3 months.

The trial was a prospective cohort study of 216 consecutive patients admitted with acute ischemic stroke to a university hospital. The decision to treat with tPA was based on the NINDS protocol with one difference: patients with involvement of more than one third of the middle cerebral artery on the baseline CT scan were excluded. A control CT scan was performed at 24 hours to determine the presence of new infarction, cortical involvement, and extension of the ischemic lesion.

 

 

Lack of improvement was defined as a difference between the NIHSS score at baseline and at 24 hours of 3 points or less. Poor outcome at 3 months was defined by a modified Rankin Scale score of 3 to 5 or death.

After adjusting for age, gender, and stroke severity, hyperglycemia at admission (glucose > 144 mg/dL), cortical involvement, and time to treatment were independent predictors of lack of improvement at 24 hours. After adjusting for age, gender, and stroke severity, lack of improvement at 24 hours was an independent predictor of poor outcome and death at 3 months. Patients with lack of improvement at 24 hours also had longer lengths of hospitalization.

9. Taylor AL, Ziesche S, Yancy C, et al. Combination of isosorbide dinitrate and hydralazine in blacks with heart failure. N Engl J Med. 2004;351:2049-57.

Neurohormonal changes, endothelial dysfunction, impaired nitric oxide availability, and oxidant stress all contribute to the structural remodeling of the left ventricle in congestive heart failure. The combination of isosorbide dinitrate, an organic nitrate that stimulates nitric oxide signaling, and the antioxidant and vasodilator hydralazine improves survival in heart failure. Based on more recent data that black patients have a clinically significant response to this combination therapy, the authors of the African-American Heart Failure Trial (A-HeFT) evaluated 1050 black patients with congestive heart failure in a randomized, double-blind, placebo controlled trial. Patients were randomized to fixed doses of isosorbide dinitrate and hydralazine plus background therapy (i.e., digoxin, ACE inhibitors, beta-blockers, diuretics, angiotensin receptor blockers) or to placebo plus background therapy. After 18 months, the trial was stopped due to a significantly higher mortality rate in the placebo group (10.2% in the placebo group vs. 6.2% with combination

therapy, p=.02); survival differences emerged at 180 days and increased progressively thereafter. The combination therapy group reported more headache and dizziness but suffered fewer exacerbations of congestive heart failure and reported improvement in subjective assessments of quality of life as measured by questionnaires. Accompanying editorials discuss the role of nitric oxide and prevention of oxidative stress in the treatment of heart failure, as well as the controversial issues surrounding race-based therapeutics.

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The Hospitalist - 2005(03)
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Sections

1. Dexter PR, Perkins SM, Mahany KS, Jones K, McDonald CJ. Inpatient computer-based standing orders vs. physician reminders to increase influenza and pneumococcal vaccination rates: a randomized trial. JAMA. 2004; 292: 2366-71.

Past studies have suggested that most patients admitted with severe pneumococcal infections have been hospitalized in the preceding 5 years, and simply being hospitalized is a potential risk factor for later pneumococcal infection. Likewise, hospitalization provides an opportunity to vaccinate high-risk patients against influenza, and raising pneumococcal and influenza immunization rates is a CMS quality improvement priority. Prior investigations have supported the use of labor-intensive manual standing orders as well as computerized reminders, but this prospective trial was conducted in 1998 and 1999 to assess the effectiveness of a computer-based system to screen for eligible patients and then generate orders to perform pneumonia and influenza vaccinations on inpatients at the time of discharge.

Over 13 months, a total of 3777 inpatients were entered into the study. The hospital computer identified patients eligible for vaccination based on common criteria and randomized them to one of two groups of physician teams. For one group of teams, the computer order-entry system would automatically generate vaccination orders at the time of discharge for vaccine-eligible patients; for the other group of teams, only computer reminders were provided to physicians. The outcome measure was administration of vaccine; long-term outcomes such as incidence of subsequent disease or mortality were not measured.

During the study period, 50% of all hospitalized patients were identified as eligible for influenza vaccination; 22% were eligible for pneumococcal vaccination. In each case, the “standing order” group received vaccine more often (influenza: 42% vs. 30%, p<.001; pneumococcal vaccine: 51% vs. 31%). The numbers were subsequently adjusted to allow for patients who had previously received vaccine, but the impressive differences persisted. Nurses reported reasons for non-administration in 98% of the eligible patients who were not vaccinated; the most common reason was patient refusal. It is not clear if the physicians knew that a study was being conducted. No adverse reactions were reported.

CMS has pushed for the development of institutional standing order sets as a tool to improve compliance with vaccination rate targets. Where the technology is available, computer systems that can screen eligible patients and generate automatic orders are an effective tool in implementing many quality-improvement initiatives, and hospitalists are in a crucial position to take an active role in their development and implementation.

2. Fang MC, Chang Y, Hylek EM, et al. Advanced age, anticoagulation intensity, and risk for intracranial hemorrhage among patients taking warfarin for a trial fibrillation. Ann Intern Med. 2004; 141: 745-52.

Warfarin has been shown to reduce risk of stroke in patients with chronic and paroxysmal atrial fibrillation. Intracranial hemorrhage remains one of the most feared complications of warfarin, especially among older patients, prompting suggestions to consider lower intensity anticoagulation among patients older than 75 years who have atrial fibrillation.

This study evaluated the relationship between the intensity of anticoagulation, risk of intracranial hemorrhage, and age of patients with atrial fibrillation.

This was a retrospective case control study conducted at a tertiary care medical center. One-hundred and seventy patients on warfarin and admitted with intracranial hemorrhage from 1993 to 2002 were matched with 1020 patients who were on warfarin but without intracranial bleed. After controlling for comorbid conditions and aspirin use, authors conducted multivariable logistic regression analysis to determine the odds of intracranial hemorrhage with regard to age and INR. The risk of intracranial hemorrhage increased at 85 years of age and at INR values of 3.5 or greater. The risk of intracranial hemorrhage at INR less than 2.0 did not differ statistically from the risk at INR of 2.0–3.0.

 

 

This study shows the risk of intracranial hemorrhage is not decreased by choosing lower intensity anticoagulation, and target INR should still be kept at 2.5 among elderly patients. However, patients older than 85 years should be counseled about their higher risk of intracranial hemorrhage.

3. Heeschen C, Hamm CW, Mitrovic V, et al. N-terminal pro-B-type natriuretic peptide levels for dynamic risk stratification of patients with acute coronary syndromes. Circulation. 2004;110: 3206-12.

Recent data demonstrate the prognostic value of assessment of neurohormonal activation in patients with acute coronary syndromes (ACS). B-type natriuretic peptide levels (BNP) and levels of the N-terminal fragment of the BNP prohormone (NT-proBNP) predict adverse long-term outcomes in patients with ACS. Investigators reviewed plasma samples of Troponin T (TnT) and NT-proBNP obtained from patients with ACS enrolled in the Platelet Receptor Inhibition in Ischemic Syndrome Management (PRISM) trial, which randomized patients to tirofiban or heparin for 48 hours and assessed mortality and myocardial infarction at 30 day follow-up. TnT and NT-proBNP determinations were available at baseline for 1791 patients, and at 48 and 72 hours from 1401 patients. Baseline NT-proBNP levels >250 ng/L were associated with significantly higher rates of death and myocardial infarction at 7 and 30 day follow-up. After adjustment for TnT and C-reactive protein levels, elevated NTproBNP levels maintained its predictive value (OR 2.7; p<.001). In patients with normal TnT levels, NT-proBNP levels identified a subgroup of patients at increased risk (OR 3.0; p=.004). However, in patients with high TnT levels (>0.1 mcg/L), NT-proBNP lost its predictive value (p=.58). More importantly, patients with normal levels of both TnT and NT-proBNP were at very low risk (0.6% event rate at 30 day follow-up).

Serial determinations of NT-proBNP levels at 48 and 72 hours were reviewed in patients without major adverse cardiac events (death or myocardial infarction); these patients were subdivided into groups with and without refractory ischemia. Patients without refractory ischemia showed a significant decline in NT-proBNP levels, whereas patients with refractory ischemia had no significant change. Persistently elevated NT-proBNP levels at 72 hours were associated with a 17.2% risk of death or MI at 30 days, compared with 0.6% risk if NT-proBNP returned to normal at 72 hours (p<.001). Neither TnT nor C-reactive protein demonstrated similar predictive value.

The study is limited by its retrospective nature, by potential selection bias by including only patients with direct evidence of coronary artery disease, and by limitations of the generalizability of its findings (e.g., to emergency department patients with chest pain).

As BNP and NT-proBNP are counter-regulatory hormones that play an active role in the response to ischemic injury, the authors suggest that NT-proBNP is a promising tool for dynamic risk assessment in patients with ACS. The authors also do not differentiate between BNP and NT-proBNP with regard to use in risk stratification, which might lead one to believe that these tests share similar predictive value. (Of note, the study was entirely funded by a company that produces an assay for NT-proBNP). Prospective trials to validate this tool are warranted

4. Heuschmann PU, Kolominsky-Rabas PL, Roether J, et al. Predictors of in-hospital mortality in patients with acute ischemic stroke treated with thrombolytic therapy. JAMA. 2004;292:1831-38.

The objective of this study was to identify factors associated with in-hospital mortality in ischemic stroke patients treated with recombinant tissue plasminogen activator (tPA). It was a prospective observational cohort study of 1658 patients conducted at 225 community and academic hospitals throughout Germany with main outcome of in-hospital mortality.

In this study 10% of patients who were treated with tPA died during their hospital stay, with 2/3 of deaths occurring in the first 7 days. Relative probability of in-hospital mortality increased with increasing patient age, with an odds ratio (OR) of 1.6 for each 10-year increment in age. Age was an independent predictor of in hospital mortality irrespective of tPA administration, with patients older than 75 years age having 4 fold higher mortality than the youngest cohort of less than 55 years age.

 

 

Other factors predicting in hospital mortality were altered level of consciousness and relative lack of experience with tPA treatment in the center. Altered level of consciousness was a predictor of stroke severity and an independent predictor of in-hospital mortality (OR 3.4). The increase in mortality in centers with limited experience with tPA administration (OR 0.97) reflected learning curve issues with these patients. The study was not designed to separate out the confounders of operator experience curve from institutional experience curves, or to derive the exact relationship between experience and outcomes.

5. McAlister FA, Bertsch K, Man J, et al. Incidence of and risk factors for pulmonary complications after non-thoracic surgery. Am J Respir Crit Care Med. 2004; published ahead of print on November 24, 2004 as doi:10.1164/rccm.200408-1069OC. Accessed January 27, 2005.

Postoperative pulmonary complications after nonthoracic surgery are a cause of significant morbidity and increased length of hospital stay. Previous studies of preoperative pulmonary assessment were limited by non-representative patient samples, conflicting results, and lack of explicit definitions of these complications. The authors conducted a prospective cohort study of 1055 patients seen in a Pre-Admission Clinic of a tertiary care university hospital. Mean age was 55 years, 50% male, and the cohort consisted of patients scheduled for intermediate risk elective surgery (upper abdominal, lower abdominal, orthopedic). They evaluated physical exam maneuvers (cough test, wheeze test, maximal laryngeal height, and forced expiratory time, all of which are described in an online data supplement) and preoperative spirometry values, and collected information on clinically significant postoperative pulmonary complications, including pneumonia, respiratory failure requiring mechanical ventilation, atelectasis requiring bronchoscopy, or pneumothorax or pleural effusion requiring percutaneous intervention. Twenty-eight patients (2.7%) suffered a pulmonary complication within 7 days of surgery, one of whom died. Length of stay was significantly prolonged in this group (mean 27.9 days vs 4.5 days, p=.006). Multivariate regression analysis revealed four variables that were independently associated with increased risk for postoperative pulmonary complications: age > 65 years, positive cough test (repeated coughing after asking the patient to inhale deeply and cough once), perioperative nasogastric tube, and anesthesia duration 2.5 hours or greater. Number of pack years smoked, FEV1, FEV1/FVC ratio, and upper abdominal surgery were associated with postoperative pulmonary complications but were not found to be independently associated by multivariate analysis.

While it is not surprising that the above risk factors are predictive of postoperative complications, this is the first study to incorporate specific exam maneuvers and spirometry into a risk prediction analysis. Limitations of this model are lack of independent validation and lack of generalizability to other populations, e.g., inpatients awaiting urgent surgery. Of note, the study further provides further support for not routinely obtaining pulmonary function testing for risk stratification prior to noncardiac surgery.

6. Mortenson, EM, Restrepo M, Anzeuto A, Pugh J. Effects of guideline-concordant antimicrobial therapy on mortality among patients with community-acquired pneumonia. Am J Med. 2004;117:726-31.

The American Thoracic Society (ATS) and the Infectious Diseases Society of America (IDSA) have published guidelines for the management of community acquired pneumonia that include recommendations for antibiotic selection. This retrospective cohort study attempted to measure the association between adherence to such guidelines and 30-day mortality in patients admitted with pneumonia to two Texas hospitals.

The characteristics of the patients studied reflect a reasonable cross-section of typical pneumonia patients, with the exception that the patients were mostly (85%) men. Of the study population, 78% were admitted through the ER, 20% admitted to the ICU, and 9% were nursing home residents. Antibiotics were considered “concordant” if they were consistent with either the most recent IDSA or ATS recommendations. The “nonconcordant” group was slightly older (66 vs. 61), generally sicker (higher rate of comorbid COPD and CVD), had more cerebrovascular disease, was more likely to present with altered mental status, and less frequently received antibiotics within 8 hours of presentation. The study did not comment on patients’ vaccination status. Thirty-day mortality was 6.2% in the guideline-concordant group, versus 21.7% in the other group (p < .001). The most common “non-concordant” regimen described was use of a beta-lactam alone, although specific antibiotic regimens were not evaluated.

 

 

While the results of this study are not surprising, they provide us with both the validation to continue practice according to existing recommendations, particularly the avoidance of monotherapy with beta-lactam antibiotics. The study also provides us with the imperative to take the lead in developing evidence-based pneumonia pathways at our own hospitals.

7. Pham MX, Whooley MA, Evans GT Jr, et al. Prognostic value of low-level cardiac troponin-I elevations in patients without definite acute coronary syndromes. Am Heart J. 2004;148: 776-82.

With the availability of rapid and highly sensitive and specific troponin testing, many patients admitted to the hospital with non-cardiac diagnoses have been recognized as having abnormal serum troponin-I or troponin-T levels, often just slightly above the reference cutoff for “normal.” While the clinical assumption is often that the elevated enzyme level does not reflect an acute coronary syndrome per se, its significance regarding the patient’s underlying cardiac health is often unclear.

Pham et al. retrospectively reviewed the 1-year mortality of 366 patients who were admitted to the San Francisco VA without evidence of acute MI or ACS either clinically or by EKG, but who had low-level troponin-I elevations (up to 3.0 ng/mL—a level that the authors state was reached by institutional consensus, and which was measured by a “first-generation” assay). These patients were admitted for a broad spectrum of diagnoses ranging from CHF to COPD to sepsis. Ninety-six percent of the patients were men; their average age was 69.

Follow-up was accomplished after a mean of 288 days and included 97% of patients. The primary endpoint was MI or death due to cardiac disease at one year; secondary endpoints were revascularization or admission for unstable angina. The primary endpoint was reached by 11% of patients with cTn-I between 1.0 and 3.0 ng/mL, and 4% of the patients with cTn-I up to 1.0 ng/mL (adjusted HR 3.4, 95% CI, 1.3 to 9.4), and the higher the cTn-I, the higher the risk. However, the authors did not test for the level of risk by specific diagnosis, so they caution against overgeneralizing their findings.

The findings of this study add to the evidence that any evidence of myocardial injury implies an increased risk of underlying heart disease and accompanying long—term cardiac complications– even if such injury occurs in the absence of ACS or known heart disease. Hospitalists often see such injury in the setting of acute infection and pulmonary disease and may be the first to recognize the possibility of CHD in a given patient. To date, guidelines addressing optimal prospective risk stratification have not been developed. Until they are, hospitalists should be aware of the ramifications of “troponin leak” and be prepared to initiate necessary inpatient monitoring and treatments, and to coordinate appropriate follow-up for these patients.

8. Saposnik G, Young B, Silver B, et al. Lack of improvement in patients with acute stroke after treatment with thrombolytic therapy: predictors and association with outcome. JAMA. 2004; 292: 1839-44.

Recombinant tissue plasminogen activator (tPA) has been shown to be one of the most efficacious therapies for acute stroke treatment. This was a systematic evaluation of predictors for outcomes at 24 hours after tPA therapy and of the prognostic significance of lack of improvement at 24 hours for long-term outcomes at 3 months.

The trial was a prospective cohort study of 216 consecutive patients admitted with acute ischemic stroke to a university hospital. The decision to treat with tPA was based on the NINDS protocol with one difference: patients with involvement of more than one third of the middle cerebral artery on the baseline CT scan were excluded. A control CT scan was performed at 24 hours to determine the presence of new infarction, cortical involvement, and extension of the ischemic lesion.

 

 

Lack of improvement was defined as a difference between the NIHSS score at baseline and at 24 hours of 3 points or less. Poor outcome at 3 months was defined by a modified Rankin Scale score of 3 to 5 or death.

After adjusting for age, gender, and stroke severity, hyperglycemia at admission (glucose > 144 mg/dL), cortical involvement, and time to treatment were independent predictors of lack of improvement at 24 hours. After adjusting for age, gender, and stroke severity, lack of improvement at 24 hours was an independent predictor of poor outcome and death at 3 months. Patients with lack of improvement at 24 hours also had longer lengths of hospitalization.

9. Taylor AL, Ziesche S, Yancy C, et al. Combination of isosorbide dinitrate and hydralazine in blacks with heart failure. N Engl J Med. 2004;351:2049-57.

Neurohormonal changes, endothelial dysfunction, impaired nitric oxide availability, and oxidant stress all contribute to the structural remodeling of the left ventricle in congestive heart failure. The combination of isosorbide dinitrate, an organic nitrate that stimulates nitric oxide signaling, and the antioxidant and vasodilator hydralazine improves survival in heart failure. Based on more recent data that black patients have a clinically significant response to this combination therapy, the authors of the African-American Heart Failure Trial (A-HeFT) evaluated 1050 black patients with congestive heart failure in a randomized, double-blind, placebo controlled trial. Patients were randomized to fixed doses of isosorbide dinitrate and hydralazine plus background therapy (i.e., digoxin, ACE inhibitors, beta-blockers, diuretics, angiotensin receptor blockers) or to placebo plus background therapy. After 18 months, the trial was stopped due to a significantly higher mortality rate in the placebo group (10.2% in the placebo group vs. 6.2% with combination

therapy, p=.02); survival differences emerged at 180 days and increased progressively thereafter. The combination therapy group reported more headache and dizziness but suffered fewer exacerbations of congestive heart failure and reported improvement in subjective assessments of quality of life as measured by questionnaires. Accompanying editorials discuss the role of nitric oxide and prevention of oxidative stress in the treatment of heart failure, as well as the controversial issues surrounding race-based therapeutics.

1. Dexter PR, Perkins SM, Mahany KS, Jones K, McDonald CJ. Inpatient computer-based standing orders vs. physician reminders to increase influenza and pneumococcal vaccination rates: a randomized trial. JAMA. 2004; 292: 2366-71.

Past studies have suggested that most patients admitted with severe pneumococcal infections have been hospitalized in the preceding 5 years, and simply being hospitalized is a potential risk factor for later pneumococcal infection. Likewise, hospitalization provides an opportunity to vaccinate high-risk patients against influenza, and raising pneumococcal and influenza immunization rates is a CMS quality improvement priority. Prior investigations have supported the use of labor-intensive manual standing orders as well as computerized reminders, but this prospective trial was conducted in 1998 and 1999 to assess the effectiveness of a computer-based system to screen for eligible patients and then generate orders to perform pneumonia and influenza vaccinations on inpatients at the time of discharge.

Over 13 months, a total of 3777 inpatients were entered into the study. The hospital computer identified patients eligible for vaccination based on common criteria and randomized them to one of two groups of physician teams. For one group of teams, the computer order-entry system would automatically generate vaccination orders at the time of discharge for vaccine-eligible patients; for the other group of teams, only computer reminders were provided to physicians. The outcome measure was administration of vaccine; long-term outcomes such as incidence of subsequent disease or mortality were not measured.

During the study period, 50% of all hospitalized patients were identified as eligible for influenza vaccination; 22% were eligible for pneumococcal vaccination. In each case, the “standing order” group received vaccine more often (influenza: 42% vs. 30%, p<.001; pneumococcal vaccine: 51% vs. 31%). The numbers were subsequently adjusted to allow for patients who had previously received vaccine, but the impressive differences persisted. Nurses reported reasons for non-administration in 98% of the eligible patients who were not vaccinated; the most common reason was patient refusal. It is not clear if the physicians knew that a study was being conducted. No adverse reactions were reported.

CMS has pushed for the development of institutional standing order sets as a tool to improve compliance with vaccination rate targets. Where the technology is available, computer systems that can screen eligible patients and generate automatic orders are an effective tool in implementing many quality-improvement initiatives, and hospitalists are in a crucial position to take an active role in their development and implementation.

2. Fang MC, Chang Y, Hylek EM, et al. Advanced age, anticoagulation intensity, and risk for intracranial hemorrhage among patients taking warfarin for a trial fibrillation. Ann Intern Med. 2004; 141: 745-52.

Warfarin has been shown to reduce risk of stroke in patients with chronic and paroxysmal atrial fibrillation. Intracranial hemorrhage remains one of the most feared complications of warfarin, especially among older patients, prompting suggestions to consider lower intensity anticoagulation among patients older than 75 years who have atrial fibrillation.

This study evaluated the relationship between the intensity of anticoagulation, risk of intracranial hemorrhage, and age of patients with atrial fibrillation.

This was a retrospective case control study conducted at a tertiary care medical center. One-hundred and seventy patients on warfarin and admitted with intracranial hemorrhage from 1993 to 2002 were matched with 1020 patients who were on warfarin but without intracranial bleed. After controlling for comorbid conditions and aspirin use, authors conducted multivariable logistic regression analysis to determine the odds of intracranial hemorrhage with regard to age and INR. The risk of intracranial hemorrhage increased at 85 years of age and at INR values of 3.5 or greater. The risk of intracranial hemorrhage at INR less than 2.0 did not differ statistically from the risk at INR of 2.0–3.0.

 

 

This study shows the risk of intracranial hemorrhage is not decreased by choosing lower intensity anticoagulation, and target INR should still be kept at 2.5 among elderly patients. However, patients older than 85 years should be counseled about their higher risk of intracranial hemorrhage.

3. Heeschen C, Hamm CW, Mitrovic V, et al. N-terminal pro-B-type natriuretic peptide levels for dynamic risk stratification of patients with acute coronary syndromes. Circulation. 2004;110: 3206-12.

Recent data demonstrate the prognostic value of assessment of neurohormonal activation in patients with acute coronary syndromes (ACS). B-type natriuretic peptide levels (BNP) and levels of the N-terminal fragment of the BNP prohormone (NT-proBNP) predict adverse long-term outcomes in patients with ACS. Investigators reviewed plasma samples of Troponin T (TnT) and NT-proBNP obtained from patients with ACS enrolled in the Platelet Receptor Inhibition in Ischemic Syndrome Management (PRISM) trial, which randomized patients to tirofiban or heparin for 48 hours and assessed mortality and myocardial infarction at 30 day follow-up. TnT and NT-proBNP determinations were available at baseline for 1791 patients, and at 48 and 72 hours from 1401 patients. Baseline NT-proBNP levels >250 ng/L were associated with significantly higher rates of death and myocardial infarction at 7 and 30 day follow-up. After adjustment for TnT and C-reactive protein levels, elevated NTproBNP levels maintained its predictive value (OR 2.7; p<.001). In patients with normal TnT levels, NT-proBNP levels identified a subgroup of patients at increased risk (OR 3.0; p=.004). However, in patients with high TnT levels (>0.1 mcg/L), NT-proBNP lost its predictive value (p=.58). More importantly, patients with normal levels of both TnT and NT-proBNP were at very low risk (0.6% event rate at 30 day follow-up).

Serial determinations of NT-proBNP levels at 48 and 72 hours were reviewed in patients without major adverse cardiac events (death or myocardial infarction); these patients were subdivided into groups with and without refractory ischemia. Patients without refractory ischemia showed a significant decline in NT-proBNP levels, whereas patients with refractory ischemia had no significant change. Persistently elevated NT-proBNP levels at 72 hours were associated with a 17.2% risk of death or MI at 30 days, compared with 0.6% risk if NT-proBNP returned to normal at 72 hours (p<.001). Neither TnT nor C-reactive protein demonstrated similar predictive value.

The study is limited by its retrospective nature, by potential selection bias by including only patients with direct evidence of coronary artery disease, and by limitations of the generalizability of its findings (e.g., to emergency department patients with chest pain).

As BNP and NT-proBNP are counter-regulatory hormones that play an active role in the response to ischemic injury, the authors suggest that NT-proBNP is a promising tool for dynamic risk assessment in patients with ACS. The authors also do not differentiate between BNP and NT-proBNP with regard to use in risk stratification, which might lead one to believe that these tests share similar predictive value. (Of note, the study was entirely funded by a company that produces an assay for NT-proBNP). Prospective trials to validate this tool are warranted

4. Heuschmann PU, Kolominsky-Rabas PL, Roether J, et al. Predictors of in-hospital mortality in patients with acute ischemic stroke treated with thrombolytic therapy. JAMA. 2004;292:1831-38.

The objective of this study was to identify factors associated with in-hospital mortality in ischemic stroke patients treated with recombinant tissue plasminogen activator (tPA). It was a prospective observational cohort study of 1658 patients conducted at 225 community and academic hospitals throughout Germany with main outcome of in-hospital mortality.

In this study 10% of patients who were treated with tPA died during their hospital stay, with 2/3 of deaths occurring in the first 7 days. Relative probability of in-hospital mortality increased with increasing patient age, with an odds ratio (OR) of 1.6 for each 10-year increment in age. Age was an independent predictor of in hospital mortality irrespective of tPA administration, with patients older than 75 years age having 4 fold higher mortality than the youngest cohort of less than 55 years age.

 

 

Other factors predicting in hospital mortality were altered level of consciousness and relative lack of experience with tPA treatment in the center. Altered level of consciousness was a predictor of stroke severity and an independent predictor of in-hospital mortality (OR 3.4). The increase in mortality in centers with limited experience with tPA administration (OR 0.97) reflected learning curve issues with these patients. The study was not designed to separate out the confounders of operator experience curve from institutional experience curves, or to derive the exact relationship between experience and outcomes.

5. McAlister FA, Bertsch K, Man J, et al. Incidence of and risk factors for pulmonary complications after non-thoracic surgery. Am J Respir Crit Care Med. 2004; published ahead of print on November 24, 2004 as doi:10.1164/rccm.200408-1069OC. Accessed January 27, 2005.

Postoperative pulmonary complications after nonthoracic surgery are a cause of significant morbidity and increased length of hospital stay. Previous studies of preoperative pulmonary assessment were limited by non-representative patient samples, conflicting results, and lack of explicit definitions of these complications. The authors conducted a prospective cohort study of 1055 patients seen in a Pre-Admission Clinic of a tertiary care university hospital. Mean age was 55 years, 50% male, and the cohort consisted of patients scheduled for intermediate risk elective surgery (upper abdominal, lower abdominal, orthopedic). They evaluated physical exam maneuvers (cough test, wheeze test, maximal laryngeal height, and forced expiratory time, all of which are described in an online data supplement) and preoperative spirometry values, and collected information on clinically significant postoperative pulmonary complications, including pneumonia, respiratory failure requiring mechanical ventilation, atelectasis requiring bronchoscopy, or pneumothorax or pleural effusion requiring percutaneous intervention. Twenty-eight patients (2.7%) suffered a pulmonary complication within 7 days of surgery, one of whom died. Length of stay was significantly prolonged in this group (mean 27.9 days vs 4.5 days, p=.006). Multivariate regression analysis revealed four variables that were independently associated with increased risk for postoperative pulmonary complications: age > 65 years, positive cough test (repeated coughing after asking the patient to inhale deeply and cough once), perioperative nasogastric tube, and anesthesia duration 2.5 hours or greater. Number of pack years smoked, FEV1, FEV1/FVC ratio, and upper abdominal surgery were associated with postoperative pulmonary complications but were not found to be independently associated by multivariate analysis.

While it is not surprising that the above risk factors are predictive of postoperative complications, this is the first study to incorporate specific exam maneuvers and spirometry into a risk prediction analysis. Limitations of this model are lack of independent validation and lack of generalizability to other populations, e.g., inpatients awaiting urgent surgery. Of note, the study further provides further support for not routinely obtaining pulmonary function testing for risk stratification prior to noncardiac surgery.

6. Mortenson, EM, Restrepo M, Anzeuto A, Pugh J. Effects of guideline-concordant antimicrobial therapy on mortality among patients with community-acquired pneumonia. Am J Med. 2004;117:726-31.

The American Thoracic Society (ATS) and the Infectious Diseases Society of America (IDSA) have published guidelines for the management of community acquired pneumonia that include recommendations for antibiotic selection. This retrospective cohort study attempted to measure the association between adherence to such guidelines and 30-day mortality in patients admitted with pneumonia to two Texas hospitals.

The characteristics of the patients studied reflect a reasonable cross-section of typical pneumonia patients, with the exception that the patients were mostly (85%) men. Of the study population, 78% were admitted through the ER, 20% admitted to the ICU, and 9% were nursing home residents. Antibiotics were considered “concordant” if they were consistent with either the most recent IDSA or ATS recommendations. The “nonconcordant” group was slightly older (66 vs. 61), generally sicker (higher rate of comorbid COPD and CVD), had more cerebrovascular disease, was more likely to present with altered mental status, and less frequently received antibiotics within 8 hours of presentation. The study did not comment on patients’ vaccination status. Thirty-day mortality was 6.2% in the guideline-concordant group, versus 21.7% in the other group (p < .001). The most common “non-concordant” regimen described was use of a beta-lactam alone, although specific antibiotic regimens were not evaluated.

 

 

While the results of this study are not surprising, they provide us with both the validation to continue practice according to existing recommendations, particularly the avoidance of monotherapy with beta-lactam antibiotics. The study also provides us with the imperative to take the lead in developing evidence-based pneumonia pathways at our own hospitals.

7. Pham MX, Whooley MA, Evans GT Jr, et al. Prognostic value of low-level cardiac troponin-I elevations in patients without definite acute coronary syndromes. Am Heart J. 2004;148: 776-82.

With the availability of rapid and highly sensitive and specific troponin testing, many patients admitted to the hospital with non-cardiac diagnoses have been recognized as having abnormal serum troponin-I or troponin-T levels, often just slightly above the reference cutoff for “normal.” While the clinical assumption is often that the elevated enzyme level does not reflect an acute coronary syndrome per se, its significance regarding the patient’s underlying cardiac health is often unclear.

Pham et al. retrospectively reviewed the 1-year mortality of 366 patients who were admitted to the San Francisco VA without evidence of acute MI or ACS either clinically or by EKG, but who had low-level troponin-I elevations (up to 3.0 ng/mL—a level that the authors state was reached by institutional consensus, and which was measured by a “first-generation” assay). These patients were admitted for a broad spectrum of diagnoses ranging from CHF to COPD to sepsis. Ninety-six percent of the patients were men; their average age was 69.

Follow-up was accomplished after a mean of 288 days and included 97% of patients. The primary endpoint was MI or death due to cardiac disease at one year; secondary endpoints were revascularization or admission for unstable angina. The primary endpoint was reached by 11% of patients with cTn-I between 1.0 and 3.0 ng/mL, and 4% of the patients with cTn-I up to 1.0 ng/mL (adjusted HR 3.4, 95% CI, 1.3 to 9.4), and the higher the cTn-I, the higher the risk. However, the authors did not test for the level of risk by specific diagnosis, so they caution against overgeneralizing their findings.

The findings of this study add to the evidence that any evidence of myocardial injury implies an increased risk of underlying heart disease and accompanying long—term cardiac complications– even if such injury occurs in the absence of ACS or known heart disease. Hospitalists often see such injury in the setting of acute infection and pulmonary disease and may be the first to recognize the possibility of CHD in a given patient. To date, guidelines addressing optimal prospective risk stratification have not been developed. Until they are, hospitalists should be aware of the ramifications of “troponin leak” and be prepared to initiate necessary inpatient monitoring and treatments, and to coordinate appropriate follow-up for these patients.

8. Saposnik G, Young B, Silver B, et al. Lack of improvement in patients with acute stroke after treatment with thrombolytic therapy: predictors and association with outcome. JAMA. 2004; 292: 1839-44.

Recombinant tissue plasminogen activator (tPA) has been shown to be one of the most efficacious therapies for acute stroke treatment. This was a systematic evaluation of predictors for outcomes at 24 hours after tPA therapy and of the prognostic significance of lack of improvement at 24 hours for long-term outcomes at 3 months.

The trial was a prospective cohort study of 216 consecutive patients admitted with acute ischemic stroke to a university hospital. The decision to treat with tPA was based on the NINDS protocol with one difference: patients with involvement of more than one third of the middle cerebral artery on the baseline CT scan were excluded. A control CT scan was performed at 24 hours to determine the presence of new infarction, cortical involvement, and extension of the ischemic lesion.

 

 

Lack of improvement was defined as a difference between the NIHSS score at baseline and at 24 hours of 3 points or less. Poor outcome at 3 months was defined by a modified Rankin Scale score of 3 to 5 or death.

After adjusting for age, gender, and stroke severity, hyperglycemia at admission (glucose > 144 mg/dL), cortical involvement, and time to treatment were independent predictors of lack of improvement at 24 hours. After adjusting for age, gender, and stroke severity, lack of improvement at 24 hours was an independent predictor of poor outcome and death at 3 months. Patients with lack of improvement at 24 hours also had longer lengths of hospitalization.

9. Taylor AL, Ziesche S, Yancy C, et al. Combination of isosorbide dinitrate and hydralazine in blacks with heart failure. N Engl J Med. 2004;351:2049-57.

Neurohormonal changes, endothelial dysfunction, impaired nitric oxide availability, and oxidant stress all contribute to the structural remodeling of the left ventricle in congestive heart failure. The combination of isosorbide dinitrate, an organic nitrate that stimulates nitric oxide signaling, and the antioxidant and vasodilator hydralazine improves survival in heart failure. Based on more recent data that black patients have a clinically significant response to this combination therapy, the authors of the African-American Heart Failure Trial (A-HeFT) evaluated 1050 black patients with congestive heart failure in a randomized, double-blind, placebo controlled trial. Patients were randomized to fixed doses of isosorbide dinitrate and hydralazine plus background therapy (i.e., digoxin, ACE inhibitors, beta-blockers, diuretics, angiotensin receptor blockers) or to placebo plus background therapy. After 18 months, the trial was stopped due to a significantly higher mortality rate in the placebo group (10.2% in the placebo group vs. 6.2% with combination

therapy, p=.02); survival differences emerged at 180 days and increased progressively thereafter. The combination therapy group reported more headache and dizziness but suffered fewer exacerbations of congestive heart failure and reported improvement in subjective assessments of quality of life as measured by questionnaires. Accompanying editorials discuss the role of nitric oxide and prevention of oxidative stress in the treatment of heart failure, as well as the controversial issues surrounding race-based therapeutics.

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