Low population prevalence of atrial fibrillation in rural Uganda: A community-based cross-sectional study.

Objectives: Atrial fibrillation (AF) is a major risk factor for stroke, which is the leading cause of cardiovascular mortality in sub-Saharan Africa. However, there is limited population-based epidemiological data on AF in sub-Saharan Africa. We sought to estimate the prevalence and correlates of AF in rural Uganda.

Methods: We conducted a cross-sectional study using community health fairs in 2015 targeting eight villages in rural Uganda. Study participants completed a medical history, a clinical exam, blood collection, and 12‑lead electrocardiographic (ECG) screening. Of 1814 participants enrolled in a parent cohort study that includes 98% of adults residing in the geographic area, 856 attended a health fair and were included in this study. Our primary outcome was AF or atrial flutter. We modelled population prevalence of the outcome with inverse probability of treatment weighting using data collected from the full population.

Results: 856 (47.2%) adults in the area attended a health fair and were included in the analysis. Health fair attendees were older (42 vs 34 years, P < 0.0001), in worse self-reported health (P < 0.0001) and more likely to be female (62% vs 49%, P < 0. 0001) compared with non-attendees. After applying weights, the estimated population mean age was 37.7 ± 14.9 years. 15% of the population was overweight or obese and 1.9% had left atrial enlargement on ECG. Despite this, the weighted estimate of AF was 0% (95%CI 0-0.54%).

Conclusions: AF appears less prevalent in rural Uganda than in developed countries. The explanations for this finding may be genetic, environmental or related to survivorship bias.