[Paradox of obesity in heart failure: results from the Spanish RICA Registry]

Abstract

Background and objectives: Obesity is a risk factor for heart failure (HF). Paradoxically, it has been described that body mass index (BMI) is inversely associated with mortality. The aim of this study was to analyse the relationship between BMI and mortality in a cohort of patients with HF.

Patients and methods: All patients included in the RICA Registry between March 2008 and September 2009 were analysed. RICA is a multicenter, prospective cohort study that includes patients admitted for decompensated HF in Spanish Internal Medicine Services. Patients were divided according to the WHO body weight categories.

Results: 712 patients were included; 54% were women and mean age was 77.3 years. Hypertensive cardiopathy was the most common etiology of HF with some differences according to BMI categories, being valvular disease more frequent among obese and overweight patients and ischemic HF among normal weight patients. Mean left ventricle ejection fraction was 50.2% and it was higher among higher BMI categories. Natriuretic peptide levels were significantly lower among higher BMI categories (P<.05). Overall mortality after one-year of follow-up was 13.9% and it was significantly lower among higher BMI categories: normal BMI 20.4%, overweight 14.7% and obesity 8.5% (P<.01). In the multivariate analysis, overweight was significantly and independently associated with an increased mortality risk in comparison with obesity: RR 3.05 (IC95% 1.24-7.54).

Conclusions: An increase in BMI was associated with lower levels of natriuretic peptides and lower mortality.