Burden of hypertension in The Gambia: evidence from a national World Health Organization (WHO) STEP survey

Background: Non-communicable diseases are increasing in sub-Saharan Africa and are estimated to account for 32% of adult deaths in The Gambia. Worldwide, prevalence of hypertension is highest in the African region (46%) and a very high proportion is undiagnosed. This study examined diagnosed and undiagnosed hypertension in The Gambian adult population.

Methods: Data were collected in 2010 from a nationally representative random sample of 4111 adults aged 25-64 years, using the World Health Organization STEPwise cross-sectional survey methods. Analyses were restricted to non-pregnant participants with three valid blood pressure measurements (n = 3573). We conducted gender-stratified univariate and multivariate regression analyses to identify the strongest sociodemographic, behavioural and biological risk factors associated with hypertension.

Results: Almost one-third of adults were hypertensive; a high proportion were undiagnosed, particularly among men (86% of men vs 71% of women with hypertension, P < 0.001). Rural and semi-urban residents and overweight/obese persons had increased odds of hypertension. Compared with urban residents, participants from one of the most rural regions had higher odds of hypertension among both men [adjusted odds ratio (AOR) 3.2; 95% CI: 1.6-6.4] and women (AOR 2.5; 95% CI: 1.3-4.6). Other factors strongly associated with hypertension in multivariate analyses were age, smoking, physical inactivity and ethnicity.

Conclusions: Rural and semi-urban residence were strongly associated with hypertension, contrary to what has been found in similar studies in sub-Saharan Africa. Intervention to reduce the burden of hypertension in The Gambia could be further targeted towards rural areas.