Using GLIM criteria, cutoff value for low BMI in Asian populations discriminates high or low muscle mass: A...

The aim of this study was to examine whether differences in muscle mass and intramuscular adipose tissue are present between patients with a moderately and severely low body mass index (BMI) as discriminated by the cutoff value for a low BMI among patients ≥70 y of age in Asian populations according to the Global Leadership Initiative on Malnutrition (GLIM) criteria.

This cross-sectional study included 345 inpatients ≥70 y of age. The participants were placed into one of the following three groups: severely low BMI (<17.8 kg/m²; n = 96), moderately low BMI (≥17.8 to <20 kg/m²; n = 81), and normal BMI (≥20 kg/m²; n = 168). Ultrasound images were obtained with B-mode ultrasound imaging. Muscle mass and intramuscular adipose tissue of the quadriceps were assessed based on the muscle thickness and echo intensity, respectively. Analysis of covariance was used to examine the differences in the quadriceps thickness and echo intensity among the three groups.

The quadriceps thickness and echo intensity in the severely low, moderately low, and normal BMI groups were 0.9 ± 0.3, 1.1 ± 0.4, and 1.4 ± 0.5 cm and 93.3 ± 20.8, 91.3 ± 19.3, 80.1 ± 21.6, respectively. The quadriceps thickness in the severely low BMI group was statistically significantly lower than that in the moderately low BMI (P < 0.001) and normal BMI (P < 0.001) groups, and the quadriceps thickness in the moderately low BMI group was also statistically significantly lower than that in the normal BMI group (P < 0.001). The quadriceps echo intensity showed no significant differences among the three groups.

The cutoff value for a low BMI discriminates high or low muscle mass. Results of this study supported the validity of 17.8 kg/m² as the cutoff value for a low BMI with which to grade the severity of malnutrition in Asian populations ≥70 y of age according to the GLIM criteria from the perspective of muscle mass.