Prognostic Utility of the Total Body Muscle Mass in Heart Failure: Insights From the JEDI-AHF Registry

Quantifying skeletal muscle mass is essential for patients with heart failure; however, common modalities, such as bioelectrical impedance analysis, can be distorted by fluid retention. The total body muscle mass (TBMM), a creatinine-cystatin C-derived marker, has been proposed as a practical blood-based surrogate of muscle mass; however, its relationship with muscle mass and its prognostic value in acute heart failure remain uncertain. Therefore, we aimed to assess whether TBMM is associated with skeletal muscle mass indices in heart failure and postdischarge all-cause mortality in patients hospitalized for acute heart failure.

This single-center retrospective study included patients hospitalized for acute heart failure at Juntendo University Hospital (January 2015-December 2021). TBMM was calculated from body weight, serum creatinine, and cystatin C, and classified using prespecified sex-specific cut-offs (men, < 38.846; women, < 26.476).

Among the 550 patients, 271 had low TBMM. Over a median follow-up of 2.6 years, 134 deaths occurred (low-TBMM, 79; high-TBMM, 55). Patients with low TBMM showed significantly lower survival and a higher risk of postdischarge mortality after adjustment. Findings were consistent across the left ventricular ejection fraction strata (< 50% and ≥ 50%). TBMM correlated strongly with appendicular skeletal muscle mass index, estimated using both anthropometric and biomarker-based models.

In patients hospitalized for acute heart failure, TBMM was strongly correlated with estimated muscle mass and independently associated with postdischarge all-cause mortality. Therefore, TBMM may complement routine risk stratification and help identify patients with heightened vulnerability related to muscle impairment.