Abstract Objective This study aimed to establish sex-specific cutoff values for sarcopenia based on the muscle parameters skeletal muscle index (SMI) and psoas muscle thickness per height (PMTH) using CT scans in a presumably healthy Caucasian study cohort. Materials and methods In this retrospective, cross-sectional study, CT scans of 350 Caucasian patients (mean age, 32 years ± 8; mean BMI, 23 (women) and 24 kg/m 2 (men)) with polytrauma, but otherwise young and presumably healthy, were evaluated. Sex-specific PMTH at the level of the umbilicus (mm/m) and the SMI (cm 2 /m 2 ) at the level of the L3 vertebral body were calculated from cross-sectional images. Two standard deviations below the mean were considered the cutoff values for sarcopenia according to the recommendations of the European Working Group on Sarcopenia in Older People (EWGSOP). To exclude random outliers, only the 5th–95th percentiles were analyzed. Results The sex-specific cutoff values for PMTH were 15.7 mm/m for women and 20.2 mm/m for men, while those for SMI were 33.2 and 44.0 cm 2 /m 2 , respectively. The intra-rater and inter-rater variabilities were consistently low, indicating the high reliability of the measurement method. Conclusions This study established sex-specific thresholds for sarcopenia based on two different muscle parameters in a presumably healthy Caucasian study cohort according to EWGSOP recommendations. Key Points Question Establishment of sarcopenia cutoff values according to the recommendations of the European Working Group on Sarcopenia in Older People (EWGSOP). Findings Cutoff values for psoas muscle thickness per height (mm/m) were 15.7 (women) and 20.2 (men); for skeletal muscle index (cm 2 /m 2 ), 33.2 and 44.0, respectively. Clinical relevance These cutoff values for two different parameters that can be determined by CT allow patients with low muscle mass to be objectively identified, thereby revealing those at high risk of manifest sarcopenia. Graphical Abstract
Wotschel et al. (Thu,) studied this question.