Prognostic values of muscle mass assessed by dual-energy X-ray absorptiometry and bioelectrical impedance analysis in older patients with heart failure.

Abstract

This study aimed to compare bioelectrical impedance analysis (BIA) and dual-energy X-ray absorptiometry (DEXA) in measuring skeletal muscle mass (MM), and its prognostic implications in old patients with heart failure. We prospectively evaluated MM measured by both BIA and DEXA in 226 hospitalized elderly (≥65 years) patients with heart failure. The cut-off values proposed by the Asian Working Group in Sarcopenia were used to define low MM. The prognostic endpoint was all-cause death. The median age of the cohort was 82 years (interquartile range: 75-87), and 51.8% of patients were men. According to the BIA and DEXA, 177 (78.3%) and 120 (53.1%) patients were diagnosed with low MM, respectively, and the two assessment tools showed poor agreement (Cohen's kappa coefficient: 0.294). During the follow-up, 32 patients (14.2%) died; only low MM defined by DEXA (hazard ratio 2.45, 95% confidence interval 1.05-5.72, P=0.039), but not BIA (hazard ratio 1.03, 95% confidence interval 0.35-3.06, P=0.955), was associated with poor prognosis after adjusting for pre-existing risk factors. Moreover, low MM defined by DEXA (net reclassification improvement: 0.58, P < 0.001), but not BIA (net reclassification improvement: -0.005, P=0.975), provides incremental prognostic predictability when considered with pre-existing risk factors and brain natriuretic peptide level at discharge. In elderly hospitalized patients with heart failure, low MM defined by DEXA and BIA show significant discordance. The MM defined by DEXA, but not BIA, provides additional prognostic value to pre-existing prognostic models. Geriatr Gerontol Int 2022; 22: 610-615.