Age- and sex-adjusted CT-based reference values for temporal muscle thickness, cross-sectional area and radiodensity.

Muscle mass has been traditionally assessed by measuring paraspinal muscle areas at the level of the third lumbar vertebra on computed tomography (CT). Neurological or neurosurgical patients seldom undergo CT scans of the lumbar region. Instead, temporal muscle thickness (TMT), cross-sectional area (TMA) and radiodensity measured from head CT scans are readily available measures of muscle mass and quality in these patient cohorts. The purpose of this retrospective study was to establish CT-based reference values for TMT, TMA and radiodensity for each decade of age from 0 to 100 years normalized by age and sex, and to define cut-off values for subjects at risk for sarcopenia as defined by the European Working Group on Sarcopenia in Older People (EWGSOP). Subjects diagnosed with a concussion at the Oulu University Hospital between January 2014 and December 2022 (n = 9254) were identified to obtain a reference population. Subjects with significant pre-existing co-morbidities were excluded. TMT, TMA and radiodensity were measured, measurement reliability was quantified, and sex-adjusted reference values were calculated for each age decade. Quantile regression was used to model age-related changes in muscle morphomics. A total of 500 subjects [250 (50.0%) males] with a mean age of 49.2 ± 27.9 years were evaluated. Inter- and intra-observer reliability was almost perfect for TMT and TMA, and substantial-to-almost perfect for radiodensity. The mean TMT, TMA and radiodensity were 5.2 ± 1.9 mm, 284 ± 159 mm2 and 44.6 ± 17.7HU, respectively. The cut-off values for reduced TMT, TMA and radiodensity for males/females using the European Working Group on Sarcopenia in Older People compliant criteria were ≤ 4.09 mm/≤3.44 mm, ≤ 166 mm2/≤156 mm2, and ≤ 35.5HU/≤35.2HU, respectively. We described a standardized CT-based TMT and TMA measurement protocol practical for clinical use with almost perfect reliability. Using the protocol, we produced quantile regression models for the detection of reduced TMT, TMA and radiodensity at the lowest 5th, 10th, 20th, 30th, 40th and 50th percentiles as well as the EWGSOP compliant criteria cut-off values for reduced muscle mass to facilitate generalizable radiological sarcopenia research.

Pesonen EK ，Arponen O ，Niinimäki J ，Hernández N ，Pikkarainen L ，Tetri S ，Korhonen TK ... -  《Scientific Reports》

Reliability and validity of measuring temporal muscle thickness as the evaluation of sarcopenia risk and the relationship with functional outcome in older patients with acute stroke.

Pre-stroke sarcopenia associated with poor functional outcomes. However, diagnosis of pre-stroke sarcopenia is often difficult in patients with acute stroke. Thus, we investigated the reliability and validity of measuring temporal muscle thickness (TMT) as an indicator of sarcopenia risk and its relationship with functional outcome in older patients with acute stroke. We conducted a cross-sectional and longitudinal study of the patients with acute elderly stroke in a single neurosurgical hospital. We measured TMT manually using brain computed tomography (CT) by two examiners. Sarcopenia risk, malnutrition risk, inflammation, comorbidities, and modified Rankin Scale (mRS) scores at 3 months after stroke were additionally assessed. Inter-rater reliability of TMT was determined by calculating the intra-class correlation coefficient ([ICC] 2,1). Multiple linear regression analyses was used to determine whether sarcopenia risk was independently associated with TMT, and logistic regression was used to evaluate the relationship between TMT and poor functional outcome (mRS > 3). A total 289 acute elderly stroke patients (163 men and 126 women; mean age: 76 years) were enrolled in this study. Regarding the reproducibility of TMT, good reliability was found; ICC2,1 = 0.759 (95 % confidence interval = 0.705-0.804). Multiple linear regression analyses for TMT after adjusting for potential confounders showed that sarcopenia risk was independently associated with TMT in older patients with acute stroke (β = -0.138, p = 0.02). After adjusting for variables, disease severity and comorbidities were the only independent predictors for poor functional outcome, but not TMT. TMT measurement using brain CT is a reliable and variable method to evaluate sarcopenia risk, but is not related to functional outcome in older patients with acute stroke.

Nozoe M ，Kubo H ，Kanai M ，Yamamoto M ，Okakita M ，Suzuki H ，Shimada S ，Mase K ... -  《-》

Relative muscle indices and healthy reference values for sarcopenia assessment using T10 through L5 computed tomography skeletal muscle area.

Derstine BA ，Holcombe SA ，Wang NC ，Ross BE ，Sullivan JA ，Wang SC ，Su GL ... -  《Scientific Reports》

The possible relation between temporal muscle mass and glioblastoma multiforme prognosis via sarcopenia perspective.

Sütcüoğlu O ，Erdal ZS ，Akdoğan O ，Çeltikçi E ，Özdemir N ，Özet A ，Uçar M ，Yazıcı O ... -  《-》

Cut-off points to identify sarcopenia according to European Working Group on Sarcopenia in Older People (EWGSOP) definition.

The reported prevalence of sarcopenia ranges widely depending on its definition criterion. European Working Group on Sarcopenia in Older People (EWGSOP) developed a practical clinical definition and consensus diagnostic criteria. This definition recommends using normative data of the study population rather than other reference populations. We aimed to define the reference cut-off values for muscle mass, muscle strength and calf circumference in Turkey in order to improve general applicability of EWGSOP criteria. Healthy young adults between 18 and 39 years of age with no known chronic disease or chronic drug usage were included in our study to serve as reference population for assessing muscle mass. Community-dwelling older outpatients were prospectively recruited from the geriatrics outpatient clinics of a university hospital for assessing hand grip strength and calf circumference. Body composition was assessed by bioimpedance analysis. Muscle strength was assessed measuring hand grip strength with a Jamar hand dynamometer. The cut-off thresholds for muscle mass were defined as the mean-2SD of the values of the young reference study population; for grip strength were calculated from ROC analyses using cut-off values that predicted gait speed < 0.8 m/s; and for calf circumference were calculated from ROC analyses using cut-off values that predicted low muscle mass. The young reference group included a total of 301 participants (187 male, 114 female; mean age: 26.5 ± 4.6 years). The cut-off thresholds for skeletal muscle mass indexes were 9.2 kg/m2 and 7.4 kg/m2 in males and females, respectively. The older community dwelling group included 406 subjects (123 male, 283 female, mean age: 76.6 ± 6.7 years). The cut-off thresholds for hand grip strength were 32 kg and 22 kg for males and females. The cut-off threshold for calf circumference was 33 cm for both males and females. The cut-off thresholds for muscle mass, grip strength and calf circumference were somewhat higher but comparable with other reference populations. Further worldwide studies from different nations and countries are needed to obtain better reference values.

Bahat G ，Tufan A ，Tufan F ，Kilic C ，Akpinar TS ，Kose M ，Erten N ，Karan MA ，Cruz-Jentoft AJ ... -  《-》