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

Abstract Aim 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 Non-ischemic DCM patients were prospectively enrolled. Regional adipose tissue, cardiac function, and myocardial tissue characteristics were measured by cardiac magnetic resonance (CMR). The primary endpoint included all-cause mortality and heart transplantation (HTX). Results 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, had lower blood pressure, worse New York Heart Association (NYHA) class, reduced biventricular ejection fraction, and higher native T1 and extracellular volume fraction (ECV) value. Similarly, reduced regional adipose tissue was associated with adverse heart remodeling, worse cardiac function, and higher diffuse myocardial fibrosis. After a median follow-up of 41 months, primary endpoint occurred in 237 patients. BMI (HR: 0.94, 95% 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. EAT volume showed highest predictive value for heart failure death/HTX (C-index: 0.70). BMI was the best predictor of arrhythmia endpoint (C-index: 0.64). Conclusions Lower BMI and thinner regional adipose tissue represented the worse clinical phenotype and adverse remodeling, and were associated with worse clinical outcomes in patients with DCM.