Pharmacology

Decentralized vs Centralized Pharmacist Treatment of Patients With Atrial Fibrillation Managed With Direct Oral Anticoagulants

Fed Pract. 2017 January;34(1):20-24

References

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7. Department of Veterans Affairs Pharmacy Benefits Management Services, Medical Advisory Panel, and VISN Pharmacist Executives. Direct oral anticoagulants (DOACs) (formerly called TSOACs) dabigatran (Pradaxa), rivaroxaban (Xarelto), and apixaban (Eliquis): Criteria for Use for Stroke Prevention in nonvalvular atrial fibrillation (AF) and Edoxaban (SAVAYSA). http://www.pbm.va.gov/PBM/clinicalguidance/criteriaforuse/Anticoagulants_Direct_Oral_DOACs_CFU_and_Algorithm_for_Nonvalvular_Atrial_Fibrillation_Sep_2016.pdf. Updated September 2016. Accessed December 6, 2016.

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Discussion

In this single-center, retrospective medication-use evaluation, the authors found a high rate of adherence to dabigatran before and after centralization of outpatient DOAC management by pharmacists. There was no statistically significant difference in bleeding events between the study periods, but primary care pharmacist visits increased by 108% from precentralization to postcentralization. Although the primary outcome findings did not refute the study's null hypothesis, results support implementing centralized pharmacist DOAC management to maintain a high rate of adherence and a low incidence of adverse outcomes and providing more primary care pharmacist services to increase access to care for other chronic diseases.

Although there was no statistically significant difference in adherence rates between study periods, the 2 groups' rates were higher than the national average of 72%, as calculated by the proportion-of-days-covered (PDC) equation (median, 74%) in a 2015 large-scale study of site-level adherence in more than 5,000 VA patients. ¹³ The authors' findings support that study's significant finding of a high rate of adherence to pharmacist-provided dabigatran treatment. This study's adherence rate also was higher than the median PDC rate reported in a 2014 study that focused on dabigatran adherence: 94% (mean, 84%; SD, 22%). ¹¹

The RHJVAMC follows national VA guidance on pharmacist follow-up for patients who receive DOACs. This follow-up focuses on frequent counseling over the first 6 months of de novo DOAC treatment and on monitoring and assessing adherence and AEs. Although there is less laboratory monitoring for DOAC treatment than for treatment with vitamin K antagonists (eg, warfarin), telephone monitoring as described in this study has been associated with a high adherence rate and minimization of AEs. The 2014 study with the 94% median PDC rate also showed an association of decreased adherence and increased harm, including combined all-cause mortality and stroke (hazard ratio, 1.13; 95% confidence interval [CI], 1.07-1.19 per 10% decrease in PDC rate). ¹¹

This study's subanalysis revealed no difference in adherence between patients initially started on dabigatran at RHJVAMC and patients who were started on dabigatran before receiving it at RHJVAMC. Each group had a high rate of adherence. Shore and colleagues found that most of the VA sites they surveyed (22/41) had anticoagulation clinics monitoring patients who were prescribed dabigatran. ¹³ Pharmacist-led monitoring of adherence and AEs led to increased adherence to dabigatran treatment (relative risk, 1.25; 95% CI, 1.11-1.41), which was the standard of care at RHJVAMC throughout their entire study. Many of these factors may explain the very high rate of adherence found in the present study, specifically in comparison to previously reported national averages.

In addition, the authors found no statistically significant difference in bleeding outcomes between the precentralization and postcentralization groups. Their incidence of bleeding was similar to the 16.6% rate reported in the package insert for dabigatran. ¹⁴ Furthermore, the safety outcomes were similar for both groups in this study, which may be attributable to the quality of patient care provided by all RHJVAMC pharmacists, particularly in the setting of dabigatran management.