Warfarin anticoagulation and outcomes in patients with atrial fibrillation: a retrospective study on different types of Ministry of Health treatment protocol / Salihah Aidit

Atrial fibrillation (AF) is a common cause of stroke, accounting for approximately 10% to 15% of all ischemic strokes and nearly a quarter of strokes for those older than 80 years. Warfarin is widely used oral anticoagulants for the treatment of AF and reducing the rate of stroke. Warfarin need frequent international normalized ratio (INR) monitoring and careful titration of warfarin doses. Literature has shown that warfarin therapy monitoring provided by a pharmacist could improve the patients' outcome. The research objective is to evaluate the clinical outcomes of warfarin therapy on different types of MOH treatment protocol. Primary endpoints included the mean time to therapeutic INR, the mean percentage of time in therapeutic range, bleeding events, and common drug interactions. We enrolled 151 patients from new warfarin patients diagnosed with AF. A retrospective, observational study was carried out in Selayang Hospital from 2009 to 2014. The INR and time in therapeutic range (TTR) levels in usual medical care (UMC) group and pharmacist-led warfarin medication therapy adherence clinic (WMTAC) after the implementation of MOH WMTAC protocol were compared. There were significant associations between UMC group and WMTAC group in TTR (p = 0.01) and INR (p = 0.02) levels. There was improvement in the pharmacists' involvement in the WMTAC where the pharmacists' recommendation accepted (p = 0.01) and expanded therapeutic INR range during WMTAC sessions (p = 0.04) were statistically significant higher in WMTAC group. Pharmacist's involvement in the WMTAC group enhances the effectiveness of the MOH Warfarin protocol.