Estimating fat mass in heart failure patients

INTRODUCTION: Body composition (BC) assessments in heart failure (HF) patients are mainly based on body weight, body mass index and waist-to-hip ratio. The present study compares BC assessments by basic anthropometry, dual energy X-ray absorptiometry (DXA), bioelectrical impedance spectroscopy (BIS), and air displacement plethysmography (ADP) for the estimation of fat (FM) and fat-free mass (FFM) in a HF population. MATERIAL AND METHODS: In this single-centre, observational pilot study we enrolled 52 patients with HF (33 HF with reduced ejection fraction (HFrEF), 19 HF with preserved ejection fraction (HFpEF); mean age was 67.7 ±9.9 years, 41 male) and 20 healthy controls. DXA was used as a reference standard for the measurement of FM and FFM. RESULTS: In the HF population, linear regression for DXA-FM and waist-to-hip ratio (r = –0.05, 95% CI: (–0.32)–0.23), body mass index (r = 0.47, 95% CI: 0.23–0.669), and body density (r = –0.87, 95% CI: (–0.93)–(–0.87)) was obtained. In HF, Lin’s concordance correlation coefficient of DXA-FM (%) with ADP-FM (%) was 0.76 (95% CI: 0.64–0.85) and DXA-FFM [kg] with DXA-ADP [kg] was 0.93 (95% CI: 0.88–0.96). DXA-FM (%) for BIS-FM (%) was 0.69 (95% CI: 0.54–0.80) and 0.73 (95% CI: 0.60–0.82) for DXA-FFM [kg] and BIS-FFM [kg]. CONCLUSIONS: Body density is a useful surrogate for FM. ADP was found suitable for estimating FM (%) and FFM [kg] in HF patients. BIS showed acceptable results for the estimation of FM (%) in HFrEF and for FFM [kg] in HFpEF patients. We encourage selecting a suitable method for BC assessment according to the compartment of interest in the HF population.