OBJECTIVES: This study sought to define the relationship between body mass index (BMI) and mortality in heart failure (HF) across the world and to identify specific groups in whom BMI may differentially mediate risk. BACKGROUND: Obesity is associated with incident HF, but it is paradoxically associated with better prognosis during chronic HF. METHODS: We studied 6,142 patients with acute decompensated HF from 12 prospective observational cohorts followed-up across 4 continents. Primary outcome was all-cause mortality. Cox proportional hazards models and net reclassification index described associations of BMI with all-cause mortality. RESULTS: Normal-weight patients (BMI 18.5 to 25 kg/m(2)) were older with more advanced HF and lower cardiometabolic risk. Despite worldwide heterogeneity in clinical features across obesity categories, a higher BMI remained associated with decreased 30-day and 1-year mortality (11% decrease at 30 days; 9% decrease at 1 year per 5 kg/m(2); p < 0.05), after adjustment for clinical risk. The BMI obtained at index admission provided effective 1-year risk reclassification beyond current markers of clinical risk (net reclassification index 0.119, p < 0.001). Notably, the "protective" association of BMI with mortality was confined to persons with older age (>75 years; hazard ratio [HR]: 0.82; p = 0.006), decreased cardiac function (ejection fraction <50%; HR: 0.85; p < 0.001), no diabetes (HR: 0.86; p < 0.001), and de novo HF (HR: 0.89; p = 0.004). CONCLUSIONS: A lower BMI is associated with age, disease severity, and a higher risk of death in acute decompensated HF. The "obesity paradox" is confined to older persons, with decreased cardiac function, less cardiometabolic illness, and recent-onset HF, suggesting that aging, HF severity/chronicity, and metabolism may explain the obesity paradox.

ANMCO Research Center Firenze Italy

Baylor College of Medicine Houston Texas

Biomarkers and Heart Diseases UMR 942 Institut National de la Santé et de la Recherche Médicale Paris France

Cardiology Department of Experimental and Applied Medicine University of Brescia Brescia Italy

Cardiology Division Department of Medicine Massachusetts General Hospital Boston Massachusetts

Cardiology Service Virgen de la Arrixaca Hospital Department of Medicine Faculty of Medicine University Murcia Murcia Spain

Department of Anesthesiology and Intensive Care Lariboisière University Hospital Assistance Publique Hôpitaux de Paris Université Paris Diderot Paris France

Department of Cardiology Steel Memorial Yawata Hospital Kitakyushu Japan

Department of Internal Medicine and Cardiology University Hospital Brno Faculty of Medicine Masaryk University Brno Czech Republic

Department of Internal Medicine University Hospital Basel Switzerland

Department of Laboratory Medicine Konventhospital Barmherzige Brueder Linz Austria

Department of Medicine Helsinki University Central Hospital Helsinki Finland

Division of Emergency Care Helsinki University Central Hospital Helsinki Finland

Emergency Department Sant'Andrea Hospital University La Sapienza Rome Italy

Internal Medicine Cardiology and Intensive Care Medicine Nippon Medical School Musashi Kosugi Hospital Tokyo Japan

Sociedad Argentina de Cardiologia Area de Investigacion SAC Azcuenaga Buenos Aires Argentina

University Medical Center Utrecht Utrecht the Netherlands

J Am Coll Cardiol. 2014 Mar 4;63(8):786-7. doi: 10.1016/j.jacc.2013.10.069. PubMed

References provided by Crossref.org

Characteristics and outcomes of patients admitted for acute heart failure in a single-centre study

Positive influence of being overweight/obese on long term survival in patients hospitalised due to acute heart failure