Objective: The relationship betweens the healthy obese phenotype and the risk of cardiovascular events remains unclear. We prospectively investigated the association between the obesity phenotype and the incidence of hypertension.
Methods: We studied 2352 participants, aged 40-69 years at baseline, with normal blood pressure (BP) from the Ansan cohort and the Ansung cohort of the Korean Genome Epidemiology Study. Participants were divided into six groups based on BMI and the metabolic syndrome (MetS) components: healthy (none of the five MetS components) normal weight (BMI <23 kg/m(2)), unhealthy (one or more MetS component) normal weight, healthy overweight (BMI 23-24.9 kg/m(2)), unhealthy overweight, healthy obesity (BMI ≥25 kg/m(2)), and unhealthy obesity. The incidence of hypertension was identified by biennial health examinations during the 8-year follow-up.
Results: After adjusting for age, sex, cohort, physical activity, smoking, alcohol consumption, and family history of hypertension and cardiovascular diseases, an increased risk for hypertension in combined cohort was observed in the healthy obesity [hazard ratio (HR): 2.20, 95% confidence interval (CI):1.34-3.60], unhealthy overweight (HR: 1.47, 95% CI: 1.00-2.14), and unhealthy obesity (HR: 2.45, 95% CI: 1.79-3.37), compared with the healthy normal weight group. In each cohort, the healthy obesity was still associated with a higher incidence of hypertension (HR 2.20, 95% CI 1.11-4.36 for the Ansan cohort and HR 2.21, 95% CI 1.01-4.83 for the Ansung cohort).
Conclusion: These findings provide evidence that the metabolically healthy obese phenotype may not be a benign condition.