Obesity Is an Independent Risk Factor for Heart Failure: Zona Franca Cohort Study

BACKGROUND: Heart failure (HF) is a major problem in developed countries. However, its relationship with obesity remains unclear, especially in low‐risk populations. The objective of the study was to analyze the relationship between obesity and HF in a low‐risk Mediterranean population. HYPOTHESIS: Obesity is an independent predictor for HF. METHODS: A prospective community‐based population cohort study with 10 years' follow‐up was conducted at 2 healthcare centers in the city of Barcelona, Spain. From a registered population of 35 275, the study included 932 randomly selected patients without HF, age 35–84 years. Obesity was defined as body mass index (BMI) ≥30 and HF according to European Society of Cardiology guidelines, confirmed by echocardiography. Cox proportional hazards regression was used to examine the association between obesity and heart failure. RESULTS: The difference in HF incidence between obese subjects (4.7%) and nonobese subjects (1.6%) was 3.1% (95% confidence interval [CI]: 0.7–5.5). In the unadjusted model, incident HF was significantly associated with BMI: the hazard ratio [HR] was 1.09 for every 1 kg/m(2) increase (95% CI: 1.05–1.14) and 3.01 for BMI ≥30 (95% CI: 1.34–6.77). After adjusting for age, sex, hypertension, ischemic heart disease, and diabetes mellitus, the results were similar: HR 1.06 (95% CI: 1.01–1.10) and HR 2.45 for BMI ≥30 (95% CI: 1.02–5.61). Overweight was not associated with HF in any of the models. The population‐attributable risk of HF due to obesity was 43.0% (95% CI: 13.9–74.9). CONCLUSIONS: High rate differences, HRs, and attributable risk indicate that obesity is an important risk factor for incident HF. Copyright © 2010 Wiley Periodicals, Inc. This work was supported by grants from Instituto de Salud Carlos III‐FEDER0 (PI080439), and by a joint contract of the Instituto de Salud Carlos III and the Health Department of the Catalan Government.