Impact of Sarcopenia Diagnosed by Point-of-Care Ultrasound on Geriatric Rehabilitation Outcomes: A Prospective Cohort Study.

OBJECTIVES

To investigate the predictive value of sarcopenia based on point-of-care ultrasound (POCUS) for geriatric rehabilitation outcomes among older patients.

DESIGN

Prospective cohort study.

SETTING AND

PARTICIPANTS

A total of 215 inpatients aged 70+ years, admitted to a tertiary geriatric rehabilitation hospital in Bern, Switzerland, in 2023.

METHODS

Sarcopenia was defined based on low grip strength and low muscle mass (European Working Group on Sarcopenia in Older People, EWGSOP2) applying definitions: (1) ultrasound rectus femoris thickness, (2) ultrasound rectus femoris cross-sectional area (CSA), and (3) bioelectrical impedance analysis (BIA). Sarcopenia definitions (4), (5), and (6) applied cutoffs of the Sarcopenia Definitions and Outcomes Consortium (SDOC) instead to each of the 3 preceding definitions. Predictive ability of these 6 sarcopenia definitions was assessed for nonhome discharge, functional and mobility impairment on discharge using area under the curve (AUC).

RESULTS

Mean age was 84.0 (SD 6.1) years and 64.2% were women. Prevalence of sarcopenia ranged between 19.1% and 34.4% depending on the sarcopenia definition applied. Overall, 49 patients (22.8%) had nonhome discharge, 53 (24.7%) had functional impairment, and 96 (49.7%) had mobility impairment on discharge. Sarcopenia using all 6 definitions was predictive for nonhome discharge, with the highest AUC for the rectus femoris thickness (EWGSOP2) (AUC, 0.68; 95% CI, 0.60-0.75). Functional impairment was best predicted by rectus femoris thickness and CSA (AUC, 0.65; 95% CI, 0.58-0.72; AUC, 0.66; 95% CI, 0.57-0.73). Rectus femoris CSA (SDOC) was the only sarcopenia definition predicting impaired mobility (AUC, 0.61; 95% CI, 0.54-0.68).

CONCLUSIONS AND IMPLICATIONS: Sarcopenia based on POCUS of the rectus femoris may contribute to prediction of rehabilitation outcomes. The predictive ability varied depending on the outcome and the cutoffs applied to diagnose sarcopenia implicating that it is key to reach agreement on the most valid sex-specific cutoffs for grip strength and muscle mass using POCUS to diagnose sarcopenia.