The role of muscle ultrasound to predict sarcopenia.

Objectives: This study aimed to provide data about the role of muscle ultrasound (US) to predict sarcopenia.

Methods: A total of 313 geriatric outpatients (age ≥65 y) were enrolled in the study. After a comprehensive geriatric assessment, anthropometric measurement and handgrip strength (HGS) data were obtained and a bioelectrical impedance analysis was performed. Sarcopenia was diagnosed using HGS and bioelectrical impedance analysis data. Gastrocnemius medialis (GC), rectus femoris (RF), and rectus abdominis (RA) muscle thickness as well as the RF cross-sectional area (CSA) were measured with US. The role of muscle US to predict sarcopenia was defined with a receiver operating characteristics analysis.

Results: The prevalence of probable and confirmed sarcopenia were 43.8% (n = 137) and 13.4% (n = 42), respectively. All muscle US parameters had positive correlations with both HGS and the fat-free mass index. There were inverse correlations between all muscle US parameters and the five-item sarcopenia questionnaire. The RF CSA had stronger correlations with the five-item sarcopenia questionnaire, HGS, and the fat-free mass index than others. The values of GC, RF, and RA muscle thickness and the RF CSA to predict sarcopenia for women/men were 13.9/13.8 mm (area under the curve [AUC]: 0.817/0.707 mm), 13/15.5 mm (AUC: 0.760/0.736 mm), 4.3/5.2 cm (AUC: 0.766/0.773 cm), and 6.6/7.0 mm (AUC: 0.740/0.688 mm), respectively.

Conclusions: GC, RF, and RA muscle thickness and the RF CSA all may predict sarcopenia accurately in geriatric outpatients.