Hypertension in Sub-Saharan Africa: A Contextual View of Patterns of Disease, Best Management, and Systems Issues.

Abstract

Sub-Saharan Africa (SSA) bears the highest burden of both communicable and noncommunicable disease and has the weakest health systems. Much attention is directed toward a rising burden of chronic disease in the setting of epidemiologic transition and urbanization. Indeed, the highest prevalence of hypertension globally is in the World Health Organization's African region at 46% of adults aged 25 and above. And while hypertension in SSA is common, its prevalence varies significantly between urban and rural settings. Although there is evidence for epidemiologic transition in urban areas, there is also evidence of static levels of hypertension within rural areas, which comprise more than 70% of the population of SSA. Furthermore, overall cardiovascular (CV) risk in rural areas remains low. The mean age of hypertensives in SSA is approximately 30s to 40s, burdening those at peak productivity. Complications of hypertension are frequent, given the poor levels of awareness and treatment (<10%) of hypertension on the continent. Such complications include primarily stroke and hypertensive heart disease, as ischemic heart disease is uncommon. Mortality associated with these complications is high, with in-hospital mortality from 2 different sites reported as around 20%. The overall burden of hypertension is likely to be more related to poor access and availability of health systems and is representative of a looming crisis in health care delivery. The best approaches to population-wide treatment are those that utilize CV risk prediction for those with stage 1 hypertension, whereas treatment is generally indicated for all those with stage 2 or greater hypertension, especially in light of the high burden of stroke in SSA. Current guidelines recommend first-line drug therapy with a diuretic or calcium channel blocker. Despite these recommendations, the major obstacles to hypertension treatment are systemic and include the availability and cost of medications, the adequacy of health facilities and systems, and the lack of health insurance to address affordability. New and innovative systems-oriented approaches are needed to address the burden of hypertension on a platform of global equity.