Sarcopenic Obesity Is Associated With Activities of Daily Living and Home Discharge in Post-Acute Rehabilitation

Abstract

Objective: The aim of this study was to evaluate the effect of sarcopenic obesity on activities of daily living and home discharge rates in adults undergoing convalescent rehabilitation. In addition, we evaluated diagnostic criteria for sarcopenic obesity to predict outcomes.

Design: A retrospective cohort study.

Setting and participants: In total, 971 Japanese patients in a post-acute rehabilitation hospital between 2014 and 2016.

Methods: Sarcopenic obesity was defined as the presence of both sarcopenia and obesity. Sarcopenia was diagnosed using muscle mass index and handgrip strength according to the criteria of the European Working Group on Sarcopenia in Older People, with the cut-off values of the Asian Working Group for Sarcopenia. Obesity was diagnosed exploratively using several definitions: percentage of body fat (FAT%), body mass index (>25 kg/m²), and fat mass index (4th quartile). Study outcomes included Functional Independence Measure-motor efficacy (score gain between admission and discharge divided by the length of stay) and the rate of home discharge. Multivariate analyses were used to determine whether sarcopenic obesity was associated with outcomes and which obesity definition was suitable for outcome prediction. P values of <.05 were considered statistically significant.

Results: After enrollment, 917 patients (mean age 74.7 ± 13.5 years; 59% women) were included in the final analyses. The frequency of sarcopenic obesity varied greatly depending on the sex and method of obesity diagnosis: 2.1% when body mass index >25 kg/m² was used for obesity diagnosis in men, and 40.7% when FAT% >25% was used in women. Further, FAT% >35% and FAT% >30% used in women and men, respectively, had the strongest association with Functional Independence Measure-motor efficacy. FAT% of >30% and >35% in women and >30 in men was associated with the rate of home discharge.

Conclusions and implications: Sarcopenic obesity was negatively associated with functional improvement and home discharge in post-acute rehabilitation. Clinical thresholds for diagnosing sarcopenic obesity should include FAT% >35 and >30% in women and men, respectively, in defining obesity in this population.

Keywords: Convalescent rehabilitation; body fat; diagnosis; obesity; older adults; prognosis.