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Percentiles for skeletal muscle index, area and radiation attenuation based on computed tomography imaging in a healthy Caucasian population.

ABSTRACT: Muscle mass is a key determinant of nutritional status and associated with outcomes in several patient groups. Computed tomography (CT) analysis is increasingly used to assess skeletal muscle area (SMA), skeletal muscle index (SMI) and muscle radiation attenuation (MRA). However, interpretation of these muscle parameters is difficult since values in a healthy population are lacking. The aim of this study was to provide sex specific percentiles for SMA, SMA and MRA in a healthy Caucasian population and to examine the association with age and BMI in order to define age- and BMI specific percentiles.In this retrospective cross-sectional study CT scans of potential kidney donors were used to assess SMA, SMI and MRA at the level of the third lumbar vertebra. Sex specific distributions were described and, based on the association between age/BMI and muscle parameters, age, and BMI specific predicted percentiles were computed. The 5th percentile was considered as cut-off.CT scans of 420 Individuals were included (age range 20-82 years and BMI range 17.5-40.7?kg/m2). Sex specific cut-offs of SMA, SMI and MRA were 134.0?cm2, 41.6?cm2/m2 and 29.3 HU in men and 89.2?cm2, 32.0?cm2/m2 and 22.0 HU in women, respectively. Correlations were negative between age and all three muscle parameters, positive between BMI and SMA/SMI and negative between BMI and MRA, resulting in age- and BMI specific percentiles.This study provides sex specific percentiles for SMA, SMI, and MRA. In addition, age- and BMI specific percentiles have been established.

SUBMITTER: van der Werf A

PROVIDER: S-EPMC5842880 | biostudies-other | 2018 Feb

REPOSITORIES: biostudies-other

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Percentiles for skeletal muscle index, area and radiation attenuation based on computed tomography imaging in a healthy Caucasian population.

van der Werf A A Langius J A E JAE de van der Schueren M A E MAE Nurmohamed S A SA van der Pant K A M I KAMI Blauwhoff-Buskermolen S S Wierdsma N J NJ

European journal of clinical nutrition 20171215 2

<h4>Background/objectives</h4>Muscle mass is a key determinant of nutritional status and associated with outcomes in several patient groups. Computed tomography (CT) analysis is increasingly used to assess skeletal muscle area (SMA), skeletal muscle index (SMI) and muscle radiation attenuation (MRA). However, interpretation of these muscle parameters is difficult since values in a healthy population are lacking. The aim of this study was to provide sex specific percentiles for SMA, SMA and MRA i ...[more]

PMID: 29242526

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Project description:BackgroundPatients with lung cancer accompanied by sarcopenia may have a poor prognosis. Normally, low muscle mass associated with sarcopenia is assessed using the skeletal muscle index (SMI). It remains unclear whether the standardized skeletal muscle area (SMA) using 2-dimensional (2D) vertebral metrics (called the skeletal muscle vertebral related index, SMVI) could substitute for SMI when it is missing. The aim of this study was to investigate the feasibility of SMVI as an alternative to SMI, and their associations with overall survival (OS) in patients with non-small cell lung cancer (NSCLC).MethodsIn this single-center study, a retrospective analysis was conducted on 433 NSCLC patients who underwent computed tomography (CT) scans. At the third lumbar vertebra (L3) level, measurements were taken for SMA, vertebral body area, transverse vertebral diameter (TVD), longitudinal vertebral diameter (LVD), and vertebral height (VH). The 4 SMVIs were skeletal muscle vertebral ratio (SMVR) (SMA/vertebral body area), skeletal muscle transverse vertebral diameter index (SMTVDI) (SMA/TVD2), skeletal muscle longitudinal vertebral diameter index (SMLVDI) (SMA/LVD2), and skeletal muscle vertebral height index (SMVHI) (SMA/VH2). The patients were categorized into low and high muscle mass groups based on SMI, and the differences in SMVIs between the 2 groups were compared to assess their correlation with SMI. Receiver operating characteristic (ROC) curves and the area under the curve (AUC) were utilized to assess the discriminatory ability. Kaplan-Meier curves were employed to compare the survival disparity between the 2 groups.ResultsWe included 191 male and 242 female patients in this study. Compared to the high muscle mass group, patients in the low muscle mass group exhibited significantly lower SMVR, SMTVDI, SMLVDI, and SMVHI (all P<0.05). All 4 SMVIs showed a positive correlation with SMI, with Spearman correlation coefficients of 0.83, 0.76, 0.75, and 0.67, respectively (all P<0.001). The AUC for diagnosing low muscle mass was higher than 0.8 for all 4 SMVI parameters. The Kaplan-Meier curve revealed that the low-risk group had a better survival probability than the high-risk group in the SMVR, SMTVDI, and SMLVDI.ConclusionsThe SMVI functions as an alternative metric for evaluating skeletal muscle mass in the assessment of NSCLC based on SMI.

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Dataset Information

Percentiles for skeletal muscle index, area and radiation attenuation based on computed tomography imaging in a healthy Caucasian population.

Publications

Percentiles for skeletal muscle index, area and radiation attenuation based on computed tomography imaging in a healthy Caucasian population.

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