Prevalence and Prognostic Differences Between Sarcopenia and Sarcopenic Obesity in Heart Failure.

Evidence directly comparing sarcopenia and sarcopenic obesity in hospitalized heart failure (HF) patients, especially in young and middle-aged individuals, remains limited. This study aimed to (1) investigate the prevalence and clinical characteristics of sarcopenia and sarcopenic obesity, and (2) compare their prognostic impacts on adverse outcomes to identify protective body composition phenotypes. The findings are hypothesized to provide new perspectives on the HF obesity paradox. This prospective cohort study was conducted from June 2022 to October 2023. The primary endpoint was 1-year HF-related readmission or all-cause mortality. Prolonged hospital stay and 90-day HF-related readmission or all-cause mortality were set as secondary outcomes. Associations of sarcopenia and sarcopenic obesity with poor clinical outcomes were analyzed using multivariate logistic regression and Cox proportional hazards regression. Sarcopenia and sarcopenic obesity prevalence was 26.4% (n=57) and 19.4% (n=42) among 216 participants, with malnutrition present in 77.2% (44/57) and 71.4% (30/42) of cases, respectively. After adjusting for covariates, both sarcopenia and sarcopenic obesity independently predicted 1-year HF-related readmission or all-cause mortality (sarcopenia vs. non-sarcopenia: HR=2.048[95%CI:1.064∼3.940], P=0.032; sarcopenic obesity vs. non-sarcopenic obesity: HR=1.932[95%CI:1.062∼3.515], P=0.031). Sarcopenic obesity also independently predicted the prolonged hospital stay (OR=2.418[95%CI:1.050∼5.567], P=0.038). In conclusion, hospitalized HF patients were susceptible to sarcopenia, sarcopenic obesity, and the double burden of malnutrition and obesity. Muscle mass, rather than fat mass, may exert protective effects, which could partially explain the HF obesity paradox. Interventions aimed at reducing obesity while ensuring the maintenance of, or an increase in, muscle mass should be developed.