International Journal of Cardiology. Heart & Vasculature | 2019
Atrial fibrillation in sub-Saharan Africa: The knowns and unknowns?
Abstract
Atrial fibrillation (AF) is themost common arrhythmia and is associatedwith increased risk of heart failure and stroke. Current treatment of AF with antiarrhythmic drugs has limited efficacy and substantial toxicity, with prevention of stroke with anticoagulants being very challenging in many AF populations [1,2]. The Global Burden of Disease (GBD) 2010 study provided evidence of progressive increase in worldwide AF burden with significant public health implications [3]. The rising AF burden can be attributed to the increase in chronic cardiovascular risk factors responsible for the development of AF substrate and disease progression [4,5]. Additionally, it is also possible that the presence of several concomitant cardiac risk factors in an individual can compound the degree of adverse atrial remodeling and risk of developingAF [6]. The increased prevalence of AF and cardiovascular risk factors is not confined to high-income countries in the Western world. In SubSaharan Africa, the prevalence of AF was estimated at 659.8 and 438.1 per 100,000 population for men and women respectively, representing a growth of 3.4% between 1990 and 2010 [3]. However, the GBD study also highlighted the low availability of data from sub-Saharan Africa and the crucial need for better estimates through targeted population surveillance studies [3]. Further, many parts of sub-Saharan Africa are undergoing epidemiological transitions with gradual adoption of Western lifestyle leading to development of new cardiovascular risk factors such as hypertension, dyslipidaemia, diabetes and obesity [7]. It is in this context that the work by Tegene et al. in this issue of the Journal, on the prevalence, risk factors and anticoagulant requirements of AF in an Ethiopian community of adults ≥ 40 years of age is welcomed [8]. In this community-based cross-sectional study of 634 adults, the authors collected data during a single household visit by trained general practitioners and nurses performing cardiovascular health examinations including a 12-lead electrocardiogram to estimate AF prevalence. A standardized questionnaire was used to collect information on medical history, lifestyle and use ofmedications. The overall prevalence of AF in this community sampling was surprisingly high at 4.3% and clearly above the estimated AF prevalence of around 0.5% from the GBD 2010 study [3]. Yet, of the risk factors reported in this study, the prevalence of the usual causes of AF such as hypertension, overweight/obesity, diabetes and ischemic heart disease were relatively low at 38%, 33%, 12%, and 13%, respectively. Perhaps, the ‘true normal’ body mass index in