Journal of Pharmacovigilance

Safety of the direct oral anticoagulants Apixaban, Dabigatran, and Rivaroxaban in an elderly ambulatory population

10^th Pharmacovigilance Congress

September 20-21, 2017 Charlotte, USA

Joseph Fava

Wayne State University, USA

Scientific Tracks Abstracts: J Pharmacovigil

Abstract:

Background: Direct oral anticoagulants (DOACs) provide patients with attractive options for anticoagulation in atrial fibrillation (AF). However, the safety of these agents in elderly patients has yet to be clearly determined in a real-world setting. Materials & Methods: We performed a single-center, retrospective cohort study of 98 cases of DOAC therapy (apixaban, dabigatran, or rivaroxaban) in a Veteran population with AF aged > 75 years. Baseline characteristics and comorbidities were collected and analyzed as potential risk factors for major and minor bleeding, using logistic regression. Dose appropriateness was assessed utilizing two versions of Cockcroft-Gault creatinine clearance (CrCl) equations. Results: A total of 33 bleeding events occurred (24 minor and 9 major) in 20 (20.4%) patient cases. In a bivariate analysis, risk of bleeding was found to be significantly increased with the presence of coronary artery disease (CAD) (p=0.02), aspirin use (p=0.01), and dual-antiplatelet therapy (p=0.04). Patients on rivaroxaban were most frequently mis-dosed (based on CrCl alone), versus apixaban or dabigatran, likely due to the comparatively high CrCl of 50 ml/min being the threshold for dose adjustment in AF. Conclusion: Overall, bleeding risk with DOAC therapy for patients > 75 years may be higher in clinical practice than seen in clinical trials. Bleeding risk seems highest in those patients on antiplatelet therapy for concomitant CAD. Rivaroxaban may be the most difficult DOAC to dose in the elderly, due to fluctuation in SCr and moderate renal impairment seen frequently in this population.

Biography :

Joseph Fava completed his Doctor of Pharmacy degree at Wayne State University in Detroit, MI in 2011. Since then he has served as pharmacy manager for the Walgreen Co. in Livonia, MI, completed a post-graduate year 1 (PGY-1) pharmacy practice residency at Beaumont Health (Oakwood Campus) in Dearborn, MI, and a PGY-2 specialty residency in ambulatory care pharmacy at the John D. Dingell Veterans Affairs Medical Center in Detroit. He currently serves as a clinical assistant professor of pharmacy practice at Wayne State. His areas of research focus include pharmacy-based chronic disease state management, immunizations, drug safety and public health.