Prevalence of cardiovascular disease in Gabon: a population study.

BACKGROUND: Data supporting epidemiological transition from a predominant burden of infectious diseases to one of chronic diseases in Africa result mostly from hospital surveys.

AIM: To estimate the cardiovascular disease (CVD) burden in Gabon.

METHODS: The study was conducted in Ntoum (8765 inhabitants). All subjects aged greater or equal to 40 years were invited to participate. Participants were interviewed about CVD history and risk factors; they responded to questionnaires on claudication and angina and had a clinical examination, including lower limb pulse palpation and bilateral brachial pressure measurement. Subjects were considered to have CVD in case of history of CVD (coronary artery, cerebrovascular and peripheral arterial diseases), a positive questionnaire or an abnormal finding during clinical examination.

RESULTS: The study included 736 subjects (313 men; 423 women). Systolic hypertension was highly prevalent (up to 47.7% and 53.7% in men and women aged 50 to 60 years, respectively). Of the 382 patients with hypertension, 74 (19.4%) were treated and only 22 (5.8%) were considered to have controlled hypertension. Overall, CVD was identified in 98 (13.3%) cases. Overall and newly diagnosed CVD prevalence rates were 14.7% and 11.5% for men and 14.9% and 8.9% for women, respectively. The presence of CVD was associated with hypertension (hazard ratio [HR] 3.69, 95% confidence interval [CI] 2.21-6.16; P<0.0001). Hypertension was predictive of stroke (HR 4.57, 95% CI 1.26-16.50; P<0.05), peripheral artery disease (HR 2.03, 95% CI 1.03-4.00; P<0.05) and subclavian artery stenosis (HR 5.79, 95% CI 2.21-15.2; P<0.05).

CONCLUSIONS: Our findings provide strong evidence of ongoing epidemiological transition in Gabon, where CVD prevalence rates increase mainly with hypertension, affecting about one in six individuals aged over 40 years.