Objectives: This study aims to evaluate effectiveness and safety of dabigatran versus warfarin in patients of non valvular atrial fibrillation in clinical practice in a tertiary care hospital of west Bengal, India by comparing the number of ischaemic stroke, bleeding events and other adverse events.

Methods: A prospective longitudinal observational study was conducted over 16 months (January 2018-April 2019). The study population comprised patients diagnosed of non valvular atrial fibrillation, receiving either dabigatran or warfarin with CHA2DS2-VASC SCORE ≥2 and patients of hyperthyroidism, treated for last one year, presenting with persistent atrial fibrillation in euthyroid state. They were divided into two groups & followed for 1 year to observe number of ischaemic strokes, thromboembolic events, bleeding events. After baseline investigations, in warfarin group INR was checked until stable therapeutic range (2-3) reached, then every 2ndmonthly both groups are followed. Relevant statistical tests were utilized for data analysis.

Results: Total 150 patients were studied. Only 2 patients (2.7%) out of 74 patients in dabigatran showed event of ischaemic stroke and in warfarin group the number of ischaemic events were 8 (10.5%) out of 76 patients. So numerically dabigatran more effectively can prevent ischaemic stroke (p value 0.098).2 patients (2.7%) in group A and 4 patients (5.3%) in group B were having minor bleeding episodes(p value 0.681).

Conclusion: Dabigatran 110 mg twice daily dose seems better than warfarin INR adjusted dose regarding effectiveness and safety profile in non valvular atrial fibrillation in Indian perspective in absolute number of ischaemic stroke and bleeding episodes.

Keywords: Non valvular atrial fibrillation, CHA2DS2-VASc score, Warfarin , Dabigatran, INR.

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Subhajit Paul

Post Graduate Trainee, Department of Pharmacology, R.G.Kar Medical College & Hospital, Kolkata