Early stage and established hypertension in sub-Saharan Africa

Abstract

Background:

Multiple studies have reported a high burden of hypertension in sub-Saharan Africa, but none have examined early stage hypertension. We examined contemporary prevalence of diagnosed, treated, and controlled stage I (130–139/80–89 mm Hg) and II (≥140/90 mm Hg) hypertension in the general population of sub-Saharan Africa.

Methods:

We analyzed World Health Organization STEPwise Approach to Noncommunicable Disease Risk Factor Surveillance surveys from 17 sub-Saharan Africa countries including 85 371 respondents representing 85 million individuals from 2010 to 2017. 

We extracted demographic variables, blood pressure, self-reported hypertension diagnosis/awareness, and treatment status to estimate prevalence of stage I and II hypertension and treatment by country. We examined diagnosis and treatment trends by national sociodemographic index, a marker of development.

Results:

Stage I hypertension prevalence (regardless of diagnosis/treatment) was >25% in 13 of 17 countries, highest in Sudan (35.3% [95% CI, 33.7%–37.0%]), and lowest in Eritrea (20.2% [18.8%–21.6%]). Combined stages I and II hypertension prevalence was >50% in 13 countries; <20% were diagnosed in every country. 

Treatment among those diagnosed ranged from 26% to 63%, and control (<140/90 mm Hg) from 4% to 17%. In 8 of 9 countries reporting on behavioral interventions (eg, salt reduction, weight loss, exercise, and smoking cessation), <60% of diagnosed individuals received counseling. 

Rates of diagnosis, but not treatment, were positively associated with sociodemographic index (P=0.008), although there was substantial variation between countries even at similar levels of development.

Conclusions:

Hypertension is common in sub-Saharan Africa but rates of diagnosis, treatment, and control markedly low. There is a large population with early stage hypertension that may benefit from behavioral counseling to prevent progression. 

Our analyses suggest that success in population hypertension care may be achieved independently of socioeconomic development, highlighting a need for policymakers to identify best practices in those countries that outperform similar or more developed countries.