Assessment Of Magnitude Of Anticoagulation Use In Patients With Atrial Fibrillation For Primary Prophylaxis Of Stroke At St. Paul’s Hospital Millennium Medical College Cardiac Clinic, Addis Ababa, Ethiopia

Abstract

Abstract Back ground- Atrial fibrillation increases a risk of stroke by five times as compared to a person without it. The best strategy to prevent stroke is to anticoagulate patients with atrial fibrillation based on their risk profile. Magnitude and the choice of anticoagulation is different at different institutions. Warfarin is a drugs of choice as primary prophylaxis in Ethiopia. Warfarin has much better efficacy than Aspirin but with narrow therapeutic index and needs frequent follow up with International normalized ratio(INR). Objective - The objective of this study was to assess magnitude of anticoagulation use in patients with AF for primary prophylaxis of stroke at St. Paul’s hospital cardiac clinic and to assess pattern of anticoagulation level among AF patients taking warfarin as primary prophylaxis for stroke. Method- A prospective longitudinal study was done from March 1- June 30 on patients who visited cardiac clinics and additional data was collected from the patient charts. Descriptive analysis was done to estimate magnitude of anticoagulation use and pattern of anticoagulation level. Results – In our study, from total of 145 study participants, females account 69% and mean age of study participants was 56.6 + 11. The magnitude of anticoagulation use was 79.3%. From those patients eligible to oral anticoagulant use 12.2% were not on oral anticoagulants, 9.8% were on Aspirin while 31.8% of ineligible patients were on warfarin. From patients taking warfarin 51.5% had sub therapeutic INR, 33.5% therapeutic and 15% supra therapeutic INR results during follow-up visits. The mean Time in Therapeutic Range (TTR) was 31.98%. Among patients on warfarin 20% had bleeding as a complication. Conclusion - In our study magnitude of anticoagulation use was high which was comparable to better set ups but there is a discrepancy on initiation and choice of drug for primary prophylaxis of stroke from standard guidelines in patients with nonvalvular atrial fibrillation. Although frequency of follow up was good; patients level of anticoagulation measured as time spent in therapeutic range was less than acceptable range, which is 60%.