Comparative five-year mortality risk in older adults with sarcopenia and sarcopenic obesity: A retrospective cohort analysis.

Abstract

Background: Sarcopenia and sarcopenic obesity (SO) are increasingly prevalent among older adults and are associated with elevated mortality risk. However, the prognostic differences between these phenotypes remain unclear. This study aimed to compare five-year all-cause mortality between older adults with isolated sarcopenia and those with SO.

Methods: In this retrospective cohort study, we analyzed 730 community-dwelling individuals aged ≥60 years who attended a geriatrics outpatient clinic between 2018 and 2023. Participants were categorized as having sarcopenia, having SO, or controls based on EWGSOP2 criteria and BMI ≥ 30 kg/m². Comprehensive geriatric assessments-including evaluations of nutrition, cognition, function, and frailty-were performed at baseline. Mortality data were obtained from institutional records. Survival outcomes were assessed using Kaplan-Meier analysis and Cox proportional hazards models.

Results: Of the participants, 123 had sarcopenia and 174 had sarcopenic obesity (SO). Over a median follow-up of five years, both groups exhibited significantly higher mortality rates than controls. Individuals with isolated sarcopenia showed the lowest survival probability (log-rank p < 0.001). In multivariable Cox analysis, chronic kidney disease, lower BMI, and older age were independent predictors of mortality.

Conclusion: Both individuals with sarcopenia and those with SO are associated with increased five-year mortality in older adults. However, individuals with isolated sarcopenia have a higher risk than those with SO, suggesting that excess adiposity may partially mitigate the adverse effects of muscle loss.