Prevalence of Hypertension in Low- and Middle-Income Countries

We aimed to obtain overall and regional estimates of hypertension prevalence, and to examine the pattern of this disease condition across different socio-demographic characteristics in low-and middle-income countries. We searched electronic databases from inception to August 2015. We included population-based studies that reported hypertension prevalence using the current definition of blood pressure 140/90 mm Hg or self-reported use of antihypertensive medication. We used randomeffects meta-analyses to pool prevalence estimates of hypertension, overall, by World Bank region and country income group. Metaregression analyses were performed to explore sources of heterogeneity across the included studies. A total of 242 studies, comprising data on 1,494,609 adults from 45 countries, met our inclusion criteria. The overall prevalence of hypertension was 32.3% (95% confidence interval [CI] 29.4–35.3), with the Latin America and Caribbean region reporting the highest estimates (39.1%, 95% CI 33.1–45.2). Pooled prevalence estimate was also highest across upper middle income countries (37.8%, 95% CI 35.0– 40.6) and lowest across low-income countries (23.1%, 95% CI 20.1– D, MPH, Saverio , PhD, lalekan A. Uthman, MD, MPH, PhD in hypertension prevalence (31.9% vs 30.8%, P1⁄4 0.6). Persons without formal education (49.0% vs 24.9%, P< 0.00001), overweight/obese (46.4% vs 26.3%, P< 0.00001), and urban settlers (32.7% vs 25.2%, P1⁄4 0.0005) were also more likely to be hypertensive, compared with those who were educated, normal weight, and rural settlers respectively. This study provides contemporary and up-to-date estimates that reflect the significant burden of hypertension in lowand middle-income countries, as well as evidence that hypertension remains a major public health issue across the various socio-demographic subgroups. On average, about 1 in 3 adults in the developing world is hypertensive. The findings of this study will be useful for the design of hypertension screening and treatment programmes in lowand middle-income countries. (Medicine 94(50):e1959) Abbreviations: BMI = body mass index, CI = confidence interval, LMICs = lowand middle-income countries, MeSH = Medical Subject Heading, mm Hg = millimetres of mercury, PRISMA = Preferred Reporting Items for Systematic Reviews and Metaanalyses, WHO = World Health Organization. INTRODUCTION H ypertension drives the global burden of cardiovascular disease, being widely acknowledged as the most common cardiovascular disorder and number 1 risk factor for mortality. The occurrence of hypertension is increasing globally, with projections estimating a 30% increase in prevalence by the year 2025. However, owing to several factors such as the ongoing nutritional transition, increasing trends in sedentary lifestyle, and other modifiable risk factors, and inadequate health care systems, populations in lowand middle-income countries (LMICs) may bear a higher burden of the disease, compared with the global average. Projections estimate that three-quarters of the world’s hypertensive population will reside in LMICs within the next decade. However, there is a dearth of evidence providing up-todate estimates of the occurrence of hypertension and its determinants across the developing regions of the world. The existing systematic reviews have, hitherto, been country-specific, or focused on African populations. Therefore, we aimed to fill this gap in the evidence by providing overall and regional estimates of hypertension prevalence across LMICs and to examine the pattern of this disease across different socio-demographic characteristics.