Prevalence of hypertension in older people in Africa: a systematic review and meta-analysis

Objective: The prevalence of hypertension in older people living on the African continent has not been comprehensively assessed. We aimed to provide accurate estimates of hypertension prevalence and variations by major predictive characteristics in this population to assist prevention and monitoring efforts. Methods: For this systematic review and meta-analysis, we searched major electronic databases for population-based studies on hypertension prevalence reported from 1 January 2000 to 5 March 2016. Two independent reviewers undertook quality assessment and data extraction. We stabilized the variance of study-specific prevalence with the Freeman-Tukey single arcsine transformation before pooling the data with random-effects models. Results: From the 2864 citations identified via searches, 91 studies providing 156 separate data contributions involving 54198 individuals met the inclusion criteria. The overall prevalence of hypertension was 55.2% (95% confidence interval 53.1-57.4). Prevalence was higher in urban compared with rural settings [59.0% (55.3-62.6) vs. 48.0% (43.8-52.3), P<0.001]. Prevalence did not differ significantly between STEPwise approach to surveillance (STEPS) and non-STEPS studies, across age groups, sex, sample size, year of publication, region, or population coverage. In cumulative meta-analysis, no temporal trend was identified over the years considered in this review. In influence analysis, no individual study was found to have a strong effect on the pooled prevalence estimate. There was substantial heterogeneity across studies (all I-2 > 94%, P<0.001) and no evidence of publication bias. Conclusion: Our findings highlight the need to implement timely and aggressive strategies for prevention, detection, and control of hypertension among older people in Africa.