High Prevalence of Hypertension in Rural and Urban Populations in Kenya

Objective: To characterize and compare hypertension prevalence in rural Kisii and urban Nairobi populations of Kenya, Africa. Methods: This observational study reviewed health records from patients at volunteer medical clinics in the rural Kisii District (n=653) and urban Nairobi District (n=825) of Kenya in August 2007. Records were analyzed for prevalence of hypertension and mean systolic and diastolic blood pressures. Results: Prevalence of hypertension in urban males was 35.6%, rural males 53.3%, urban females 25.7%, and rural females 44.5%. Rural individuals were almost twice as likely to be hypertensive compared to their urban counterparts [for males, OR = 1.9, (95%CI 1.2 to 3.1), p=0.0067; for females, OR = 1.8, (1.3 to 2.4), p=0.015] after adjusting for age, weight, and presence of acute illness. Rural males and females exhibited significantly more hypertension in the younger 25-34 year age group. Rural males had significantly higher diastolic blood pressures (84.3 v 80.9 mm Hg, p=0.015) than urban males, but not higher systolic blood pressure (136.0 v 132.1 mm Hg, p=0.107). Rural females had higher systolic blood pressures than urban females (132.9 v 127.1 mm Hg, p=0.0004), but showed no difference in diastolic blood pressures (80.3 v 79.9, p=0.426). Conclusion: Overall hypertension prevalence is significantly higher than previously reported. The rural Kisii population had higher prevalence of hypertension and higher blood pressure than the urban Nairobi population, and surprisingly showed younger age groups exhibiting more hypertension. These findings are contrary to other studies of hypertension in Africa, and invite further investigation.