Body mass index, regional adipose deposition, and clinical outcomes in non-ischaemic dilated cardiomyopathy: a prospective cohort study

AIMS: This study aims to assess the relationship between body mass index (BMI), subcutaneous adipose tissue (SAT), visceral adipose tissue (VAT), epicardial adipose tissue (EAT), pericardial adipose tissue (PAT), and clinical outcomes in dilated cardiomyopathy (DCM) patients. METHODS AND RESULTS: Non-ischaemic DCM patients were prospectively enrolled. Regional adipose tissue, cardiac function, and myocardial tissue characteristics were measured by cardiac magnetic resonance. The primary endpoint included all-cause mortality and heart transplantation (HTX). This study enrolled 1042 DCM patients (68% men, mean age 48 ± 15 years, mean BMI 23.9 ± 4.0 kg/m2). Underweight patients were more frequently women and had lower blood pressure, worse New York Heart Association class, reduced biventricular ejection fraction, and higher native T1 and extracellular volume fraction value. Similarly, reduced regional adipose tissue was associated with adverse heart remodelling, worse cardiac function, and higher diffuse myocardial fibrosis. After a median follow-up of 41 months, primary endpoint occurred in 237 patients. Body mass index [hazard ratio (HR): 0.94, 95% confidence interval (CI): 0.90-0.98, P = 0.006], VAT thickness (per 1 mm: HR 0.94, 95% CI: 0.91-0.97, P < 0.001), and EAT volume (per 1 mL: HR 0.96, 95% CI: 0.95-0.97, P < 0.001) were independent predictors of primary endpoint. Epicardial adipose tissue volume showed the highest predictive value for heart failure death/HTX (C-index: 0.70). Body mass index was the best predictor of arrhythmia endpoint (C-index: 0.64). CONCLUSION: Lower BMI and thinner regional adipose tissue represented the worse clinical phenotype and adverse remodelling and were associated with worse clinical outcomes in patients with DCM.