Prevalence, treatment and control of hypertension in La Réunion: the RÉDIA population-based cohort study

A better knowledge of prevalence, management and determinants of hypertension is needed in regions in epidemiological transition to adapt the strategies of public health screening and prevention, and to reduce the burden of cardiovascular diseases. We conducted a prospective cohort study including 4610 participants aged between 18 and 69 years and representative of the general population of La Réunion, a French overseas island located in the western Indian Ocean. The median time between inclusion and follow-up was 7.4 years. Blood pressure data at baseline and follow-up of 3087 participants were analyzed. We found a high prevalence of hypertension, especially in women (36.7% [34.5-39.0]) and in men (40.3% [37.6-43.0]) and in the under 30s (17.1% [14.0-20.5]), with an increase of 10% at follow-up. Treatment rates were very low in men (19.5% versus 39.1% in women) as was awareness of their condition (25.7% versus 44.6%). Blood pressure control rates were similar (18% at baseline and 34% at follow-up for both sexes). Diagnosis of hypertension at follow-up among subjects normotensive at baseline was independently associated with obesity at baseline (relative risk (RR) = 1.40 [1.12-1.75] for BMI between 27 and 30 kg/m² and 1.72 [1.33-2.25] for BMI ≥30 kg/m² as compared with BMI <27 kg/m²) and HbA1C (RR =1.12 [1.05-1.19] per %), suggesting a prominent role of insulin resistance in our population. Our study provides original data that cannot be assimilated to any existing model and should guide the implementation of original community-based programs in such countries.