Ten-year change in blood pressure levels and prevalence of hypertension in urban and rural Cameroon

Background Hypertension is becoming increasingly important in sub-Saharan Africa. However, evidences in support of this trend with time are still not available. The aim of this study was to evaluate the 10-year change in blood pressure levels and prevalence of hypertension in rural and urban Cameroon. Methods Two cross-sectional population-based surveys in Yaounde (urban area) and Evodoula (rural area) in 1994 (1762 subjects) and 2003 (1398 subjects) used similar methodologies in women and men aged 3:24 years. Data on systolic and diastolic blood pressures (SBP and DBP), body mass index, educational level, alcohol consumption and tobacco smoking were collected during the two periods. Results Between 1994 and 2003, blood pressure levels significantly increased in rural women (SBP, +18.2 mm Hg; DBP, +11.9 mm Hg) and men (SBP, +18.8 mm Hg; DBP, +11.6 mm Hg), all p<0.001. In the urban area, SBP increased in women (+8.1 mm Hg, p<0.001) and men (+6.5 mm Hg, p<0.001), and DBP increased only in women (+3.3 mm Hg, p<0.001). The OR (95% Cl) adjusted on confounders comparing the prevalence of hypertension (blood pressures 140/90 mm Hg and/or treatment) between 2003 and 1994 ranged from 1.5 (1.1 to 2.2) in urban men to 5.3 (3.2 to 8.9) in rural men. Conclusion Blood pressure levels of this population have deteriorated over time, and the prevalence of hypertension has increased by twofold to fivefold. Adverse effects of risk factors could account for some of these changes. Prevention and control programmes are needed to reverse these trends and to avoid the looming complications.