Appendicular lean mass index is a major determinant of cardiorespiratory fitness in patients with obesity-related heart failure with preserved ejection fraction (HFpEF). Moreover, appendicular lean mass index can be used to diagnose sarcopenia and sarcopenic obesity in this population.

We aimed to validate the ability of segmental single-frequency bioelectrical impedance analysis (SF-BIA) to assess body composition compared with dual-energy x-ray absorptiometry (DXA) in patients with HFpEF and obesity, with a focus on appendicular lean mass index for its critical role in diagnosing sarcopenia and sarcopenic obesity. We analyzed 62 euvolemic patients from a heart failure outpatient clinic with persistent obesity-related HFpEF (83.8% women, 60.8 ± 2.8 years of age).

We used DXA and segmental SF-BIA. Strong correlations were found between segmental SF-BIA and DXA for appendicular lean mass index (r = 0.897), appendicular fat mass index (r = 0.864), fat mass (r = 0.968), fat mass percentage (r = 0.867), fat-free mass (r = 0.954), fat-free mass percentage (r = 0.852), fat mass index (r = 0.97), and fat-free mass index (r = 0.88) (all p < 0.001), without significant proportional bias for all parameters, except for appendicular fat mass index.

Segmental SF-BIA-measured body composition shows strong correlations, appropriate agreements, and no proportional bias compared with DXA. Segmental SF-BIA should be considered in patients with obesity-related HFpEF.