Prevalence, Awareness, and Treatment of Hypertension in 37 African Countries: Trends From 2003 to 2022

Abstract

Background: Despite the high burden of hypertension in Africa, multicountry and representative studies addressing hypertension-related outcomes are scarce.

Objectives: We estimated the distribution, time trends, and determinants of hypertension status, awareness, treatment, and control in the World Health Organization (WHO) African Region (AFRO) countries.

Methods: We analyzed individual-level data from 61 national, subnational, or community surveys, including WHO STEPwise approach to NCD risk factor Surveillance surveys and Demographic and Health Surveys, conducted between 2003 and 2022 in 37 AFRO countries. Prevalence rates and their 95% CIs were age-standardized and accounted for survey and study-level weights. ORs were estimated using hierarchical logistic regression analysis with random effects for country and survey year.

Results: Of the 251,761 participants, 59.5% were female, mean age: 37.1 ± 12.3 in females and 38.6 ± 12.6 in males. Hypertension was diagnosed in 28.9% (95% CI: 27.6%-30.2%) of females and 26.1% (95% CI: 24.5%-27.7%) of males. Among hypertensive individuals, awareness was 62.4% (95% CI: 58.5%-66.3%) for females and 50.5% (95% CI: 44.5%-56.4%) for males; antihypertensive treatment was 15.0% (95% CI: 13.1%-16.9%) in females and 8.4% (95% CI: 6.7%-10.2%) in males; and control rates were 7.3% (95% CI: 5.8%-8.8%) for females and 3.7% (95% CI: 2.4%-4.9%) for males. In multivariable hierarchical analysis, prevalence of hypertension and awareness were associated with older age, higher body mass index, retirement, former smoking (females only), higher education level (with awareness only), and higher alcohol consumption (with awareness in males only). Conversely, lower odds of treatment and control were associated with current smoking and high alcohol consumption. Hypertension-related outcomes were also influenced by contextual (country-level) factors including life expectancy at birth, Gender Development Index, grams of fat per day per capita, Gross Domestic Product per capita, employment in agriculture, and urbanization. Between 2003 and 2022, the overall number of hypertension cases nearly doubled from 241 to 390 million, while treatment and control rates rose from 11.8% to 18.4% and from 7.6% to 9.2%, respectively.

Conclusions: Despite improvement in hypertension awareness, the burden of untreated and uncontrolled hypertension in adults remains substantial in the AFRO with notable sex disparities.

Keywords: WHO African Region; awareness; control; hypertension; pooled cross-sectional studies; treatment.