Beyond the third lumbar vertebra (L3): Thoracic computed tomography-derived muscle mass and quality assessment as a practical alternative for body composition analysis.

Recent studies have correlated dysphagia with ultrasound-measured quadriceps muscle mass and quality. Computed tomography (CT) is more precise than ultrasound for estimating muscle mass and quality. We aimed to investigate the possible associations of chest CT-determined trunk muscle mass and quality with dysphagia. A cross-sectional study. Older inpatients in a geriatric department of a university hospital. Self-reported dysphagia was determined by the Dysphagia Handicap Index. Unenhanced chest CT images were segmented to calculate skeletal muscle area (SMA) and intermuscular adipose tissue (IMAT). Skeletal muscle index (SMI) was calculated via SMA/ height squared. The percentage of IMAT (IMAT%) was calculated by IMAT% = IMAT/ (SMA + IMAT) × 100%. Mimics software was applied to calculate the mean skeletal muscle radio density (SMD).The semiquantitative food frequency method, the Barthel Index (BI), and the Mini Nutritional Assessment Short-Form (MNA-SF) were used to evaluate energy intake, activities of daily living, and nutrition status, respectively. Among the 212 participants (mean age: 84years), 89 (42%) had self-reported dysphagia. After adjustment for age, nutrition status, energy intake, and other confounders, the SMI (adjusted OR 0.91, 95% CI 0.86, 0.96) was negatively associated with dysphagia, whereas the IMAT (adjusted OR 1.08, 95% CI 1.01, 1.16) and the IMAT% (adjusted OR 1.10, 95% CI 1.04,1.17) were positively associated with dysphagia. However, the SMD (adjusted OR 0.99, 95% CI 0.94, 1.05) was not significantly associated with dysphagia. The subgroup analyses indicated that only the SMI (adjusted OR 0.92, 95% CI 0.86, 0.97) and the IMAT% (adjusted OR 1.08, 95% CI 1.01, 1.17) were significantly associated with dysphagia in men. None of these indicators was significantly associated with dysphagia in women. Trunk muscle mass and quality (estimated by chest CT-derived SMI and IMAT%, respectively) were significantly associated with self-reported dysphagia in older inpatients, especially in men. IMAT% might be a more sensitive muscle quality indicator than IMAT (or SMD). These results merit further investigation in prospective studies.

Malnutrition in Relation to Muscle Mass, Muscle Quality, and Muscle Strength in Hospitalized Older Adults.

Objectives: Sarcopenia is an important predictor of dependence in activities of daily living (ADL disability); however, the association between muscle quality and ADL disability has not been established. We aimed (1) to assess the feasibility of measuring trunk muscle mass and muscle quality by chest CT images; and (2) to explore the possible associations of ADL disability with these muscle mass and muscle quality indicators among older inpatients.Methods: We included older patients in an acute care ward. ADL disability was defined as the Barthel Index (BI) score ≤ 60 points. Unenhanced chest CT images at the 12th thorax (T12) vertebral level were used to segment skeletal muscle area (SMA) and intermuscular adipose tissue (IMAT) and to measure the mean skeletal muscle radiodensity (SMD). Skeletal muscle index (SMI), the muscle mass indicator, was calculated by SMA (cm2)/body height squared (m2). The percentage of IMAT (IMAT%) was calculated using the equation: IMAT% = IMAT/(SMA+ IMAT) ×100%. Skeletal muscle radiodensity, IMAT, and IMAT% were the muscle quality indicators. Kendall's tau rank correlation coefficients (τ) were calculated to explore the correlations. Univariate and multivariate logistic regression models were performed to calculate odds ratios (OR) and 95% confidence interval (CI).Results: We included 212 participants. Skeletal muscle index and SMD were positively and significantly associated with the BI score (τ = 0.14 and 0.31, respectively, both P < 0.001); whereas IMAT and IMAT% were negatively and significantly associated with the BI score (τ = −0.21, P < 0.001; τ = −0.21, P < 0.012). After adjusting for confounders, SMI (adjusted OR 1.03, 95% CI 0.97–1.09) was not independently associated with ADL disability; however, SMD (adjusted OR 0.94, 95% CI 0.88–0.99), IMAT (adjusted OR 1.11, 95% CI 1.03–1.20), and IMAT% (adjusted OR 1.09, 95% CI 1.02–1.16) were independently associated with ADL disability. Subgroup analysis found similar results in men; however, none of these indicators were independently associated with ADL disability in women.Conclusion: Trunk muscle quality indicators (SMD, IMAT, and IMAT%) measured by chest CT images, but not SMI, are independently associated with ADL disability in a single-center study population of older inpatients, especially in men. Further research is necessary to validate our findings.

Skeletal muscle radiodensity is prognostic for survival in patients with advanced non-small cell lung cancer

BackgroundMuscle mass and muscle quality assessed by computed tomography (CT) have been associated with poor prognosis in oncology and surgery patients, but the relevant evidence was limited in older patients. We hypothesized that muscle mass and muscle quality indicators derived from opportunistic chest CT images at the 12th thorax vertebra level (T12) could predict in‐hospital death, length of hospital stay (hospital LOS), and hospital costs among older patients in acute care wards.MethodsWe conducted a prospective cohort study. Older patients admitted to the acute geriatric wards of a teaching hospital were continuously recruited. Chest CT images were analysed using SliceOmatic software. The skeletal muscle area, skeletal muscle radiodensity, and intermuscular adipose tissue (IMAT) at the T12 level were measured. Skeletal muscle index (SMI) was calculated using skeletal muscle area divided by body height squared.ResultsWe included 1135 older patients with a median age of 80 years (interquartile range, 73 to 85 years), 498 (44%) were women, 148 (13%) patients died during hospitalization. The SMI and SMD were negatively correlated to age (ρ = −0.11, P < 0.001, ρ = −0.30, P < 0.001, respectively), whereas the IMAT was positively correlated to age (ρ = 0.27, P < 0.001). Compared with survivors, dead patients had significantly lower SMI in men (P < 0.001) but not in women (P = 0.760). After adjusting for sex and other potential confounders, the SMI [increased per 1 cm2/m2, odds ratio (OR) 0.96, 95% confidence interval (CI) 0.93 to 0.99] and SMD (increased per 1 Hounsfield unit, OR 0.93, 95% CI 0.90 to 0.96) were negatively and independently associated with in‐hospital death, whereas the IMAT (increased per 1 cm2, OR 1.09, 95% CI 1.05 to 1.14) was independently and positively associated with in‐hospital death. None of the SMI, SMD, or IMAT was significantly related to long hospital LOS or increased hospital costs.ConclusionsChest CT‐derived muscle mass indicator (T12 SMI) and muscle quality indicators (T12 SMD and T12 IMAT) may serve as prognostic factors for predicting in‐hospital death among older inpatients. Opportunistic chest CT images might be an overlooked resource for measuring muscle mass and muscle quality and for predicting short‐term prognosis in older inpatients.

e18648 Background: Cancer-related malnutrition and cachexia can lead to body composition changes. BCM can be assessed at the third lumbar (L3) vertebra by CT, which is available as part of pre-trial evaluation. We previously found that malnutrition and low psoas muscle area (PMA) are associated with adverse P1 outcomes including higher rates of ≥ Grade 3 toxicity (G3T). Here we evaluate the relationships between comprehensive cross-sectional muscle and adipose tissue BCM at L3 on P1 outcomes. Methods: Baseline CT scans for 82 patients (pts) were reviewed and images at the level of L3 were identified by 3 independent reviewers. A CT L3 image selected by at least 2 reviewers underwent analysis by Slice-O-Matic software (Tomovision, Canada) to generate BCM including: skeletal muscle area (SMA), skeletal muscle radiodensity (SMD), and adipose tissue area [intermuscular (IMAT), visceral (VAT), subcutaneous (SAT), and total adipose (TAT)] in cm2. SMA was normalized by height (m2), yielding cross-sectional skeletal muscle index (SMI). We stratified pts by having a SMI, SMD, IMAT, VAT, SAT, and TAT above or below the median value. We evaluated for associations between BCM and the following outcomes: rates of ≥ G3T, frequency of dose reductions/interruptions, hospitalizations, tumor response, disease control, duration on study (DOS), and overall survival (OS). Chi-square analysis was used to determine statistical significance between groups. Kaplan-Meier curves were used to compare DOS and OS. A multivariable analysis (MVA) was conducted via logistic regression to evaluate the association between SMI, VAT, PMA and ≥ G3T controlling for age and gender. Results: 82 P1 pts were included (38 M, 45 F), with a median age of 60 (range 28-85). The most common disease site was gastrointestinal (33%). Mean SMI was 44.78 cm2/m2 (range 25.70-79.89). Higher SMI was associated with a reduced risk of ≥ G3T (36.6% vs 58.5%; p = 0.047) and a trend towards improved OS (p = 0.07). There was no association between SMD, IMAT, SAT, or TAT and toxicity, however, higher VAT was associated with reduced risk of ≥ G3T (31.7% vs 63.4%, p = 0.004), and improved response to therapy (p = 0.001). A MVA controlling for age and gender showed that reduced SMI (AUC 0.7072), increased VAT (AUC 0.7597), and reduced PMA (AUC 0.757) were similar in their ability to predict ≥ G3T. Conclusions: P1 trials are designed to determine the safety and tolerability of investigational agents. In this population of P1 pts, BCM including higher baseline CT L3 SMI and VAT were associated with a reduced risk of ≥ G3T. BCM were also tied to efficacy as high VAT was associated with improved tumor response while a trend towards improved OS was noted for pts with higher baseline SMI. Future research should examine the value of integrating CT-based BCM into dose-selection algorithms when evaluating safety in P1 trials to minimize treatment-related toxicity and optimize therapeutic benefit.

648 Background: Body composition has emerged as a potential prognostic factor for outcomes in early-stage CRC. Specifically, muscle mass and quality and visceral fat have been shown to be related to overall survival (OS) and disease-free survival (DFS). The objective of this study was to determine associations of sarcopenia, reduced skeletal muscle radiodensity (SMR) and visceral obesity (VO) with 5-year OS and DFS. Methods: Muscle and visceral fat at the time of diagnosis were quantified in a retrospective cohort of consecutive, early-stage CRC patients (pts), identified from a prospectively collected cancer database. Skeletal muscle area on computed tomography (CT) was measured and normalized by height (m2) in order to compare skeletal muscle index (SMI) between pts. Mean SMR and visceral fat area were measured. All parameters were analyzed using Kaplan-Meier curves and univariate Cox regression. Sarcopenia was defined as SMI &lt; 41 cm2/m2 in females and &lt; 43 cm2/m2 in males with BMI &lt; 25 kg/m2 and &lt; 53 cm2/m2 with BMI &gt; 25 kg/m2. Reduced SMR was defined as &lt; 41 HU if BMI &lt; 25 kg/m2 and &lt; 33 HU if BMI &gt; 25 kg/m2. VO was defined as VAT &gt; 160cm2 in males and &gt; 80cm2 in females. Results: We identified 968 pts with available CTs and anthropometric data. Prevalence of sarcopenia was 44.5% in males and 59.6% in females. Myosteatosis was present in 60.9% of pts. The mean length of follow up was 5.0 years, with 254 patients developing recurrent disease and 351 deaths. Males with sarcopenia and myosteatosis had worse overall survival (HR, 0.69, p = 0.005; HR 0.49, p &lt; 0.001) but no difference in DFS. Presence of VO was not associated with worse OS or DFS. There was no difference in OS for females with sarcopenia or VO, but myosteatosis predicted reduced OS (HR 0.53, p = 0.004). There was no difference in DFS for females by presence of sarcopenia, myosteatosis or VO. Conclusions: Body composition, specifically sarcopenia and myosteatosis, are highly prevalent in CRC pts treated with curative intent, and their presence is associated with reduced OS. Therefore, skeletal muscle mass and radiodensity are important prognostic factors in CRC outcomes, which are easily attained in a clinical setting.

Data on longitudinal changes of computed tomography (CT)-determined visceral fat area (VFA), skeletal muscle area (SMA) and skeletal muscle radiodensity (SMD) after adrenalectomy are limited in patients with hypercortisolism. To examine the association of severity of cortisol excess and improvement of CT-based muscle and fat parameters after adrenalectomy. Retrospective observational cohort study. One hundred thirty-four patients with overt Cushing's syndrome (CS; n=39), mild autonomous cortisol excess (MACE; n=57), or nonfunctioning adrenal tumour (NFAT; n=38) at a tertiary endocrinology institution between 2006 and 2017 were included. Changes in CT-determined VFA, visceral-to-subcutaneous fat ratio (VSR), SMA, skeletal muscle index (SMI), and SMD measured at the third lumbar vertebra (L3). At baseline, CS patients had higher VFA, lower SMA, SMI and SMD values, compared to NFAT or MACE patients. Compared to NFAT, significant decreases in VFA and increases in SMA, SMI and SMD was observed in CS 1year after adrenalectomy. In MACE, adjusted mean changes of SMD but not VFA, SMA or SMI differ significantly compared to NFAT (+8.9% vs -3.4%, P=0.032). In a multivariate linear regression model, the increase by 1μg/dL of post-dexamethasone serum cortisol at baseline was independently associated with greater reduction of VFA (-3.95%), VSR (-3.07%), and increase in SMD (+0.92%, P<0.05 for all) after adrenalectomy. The severity of cortisol excess was associated with greater improvement of L3 VFA, VSR and SMD 1year after adrenalectomy. These CT-based markers may allow more objective assessment of treatment benefit at earlier stage.

BackgroundMeasuring muscle mass and muscle quality based on chest Computed Tomography (CT) images would facilitate sarcopenia and myosteatosis research. We aimed (1) to measure muscle mass and myosteatosis based on chest CT images at the 12th thoracic vertebra level and compare the relevant indicators with whole-body skeletal muscle mass (BSM) and whole-body fat mass (BFM) measured by bioelectrical impedance analysis; and (2) to determine the cut-off points of these indicators for diagnosing sarcopenia or myosteatosis in healthy Chinese adults.MethodsChest CT images were analyzed using a segmentation software. Skeletal muscle area (SMA), skeletal muscle radiodensity (SMD), and intermuscular adiposity tissue (IMAT) were measured. Skeletal muscle indices (SMIs) and IMAT/SMA ratio were calculated.ResultsWe included 569 participants. SMA, SMA/height2, and SMA/BMI were strongly and positively correlated with BSM (r = 0.90, 0.72, and 0.69, respectively, all p < 0.001); whereas SMA/weight was moderately and positively correlated with BSM (r = 0.38, p < 0.001). IMAT and IMAT/SMA were strongly and positively correlated with BFM (r = 0.67 and 0.58, respectively, both p < 0.001). SMD was moderately and negatively correlated with BFM (r = − 0.40, p < 0.001). We suggest SMA/height2 (< 25.75 cm2/m2 in men and < 20.16 cm2/m2 in women) for diagnosing sarcopenia and SMD (< 37.42 HU in men and < 33.17 HU in women) or IMAT (> 8.72 cm2 in men and > 4.58 cm2 in women) for diagnosing myosteatosis.ConclusionsMuscle mass indicators (SMA and SMIs) and muscle quality indicators (SMD, IMAT, and IMAT/SMA) measured by chest CT images are valuable for diagnosing sarcopenia and myosteatosis, respectively.

Objective To investigate the relationship between muscle mass reduction and quality of life in elderly lung cancer patients at the initial visit. Methods Totally 221 patients with non-small cell lung cancer undergoing chest and abdominal CT examination were included in this study at Fenyang Hospital in Shanxi Province.The Pearson's correlations of skeletal muscle index(SMI)and skeletal muscle radiodensity(SMD)with the disease stage, physical function, role of physical function, global quality of life, fatigue and dyspnea were analyzed. Results The average age of 221 patients was(70.2±9.0)years.The mean SMI for men and women was(46.7±7.8)cm2/m2 and(39.4±6.4)cm2/m2 respectively.Multivariate linear regression analysis showed that SMI affected the body function, role of physical function, global quality of life, and fatigue dimension(all P<0.05), and SMD affected the physical function of life quality and dyspnea dimension(P<0.05). SMI was related to the physical function and role of physical function(men: r=0.287 and 0.245, P=0.001 and 0.006; women: r=0.296 and 0.395, P=0.004 and 0.000). In male patients, SMI was also associated with low global quality of life and fatigue(r=0.191 and -0.198, P=0.032 and 0.026). The above relationships did not change even after adjusting for the effect of age and disease stages.Low SMD was associated with low physical function and dyspnea in both men and women(men: r=0.287 and 0.245, P=0.037 and 0.049; women: r=0.281 and -0.262, P=0.006 and 0.010), and SMD was associated with dyspnea only in women even after adjusting for age and disease stages.A correlation between SMI and the disease stage was found in both men and women(male: r=-0.266, P=0.003; female: r=-0.223, P=0.005). Conclusions Changes in muscle mass may affect the physical function, role of physical function and global quality of life in elderly patients with non-small cell lung cancer. Key words: Lung neoplasms; Muscle, skeletal; Quality of life

ObjectiveTo investigate the role of preoperative body composition analysis for muscle and adipose tissue distribution on long-term oncological outcomes in patients with middle and low rectal cancer (RC) who received curative intent surgery.MethodsA total of 155 patients with middle and low rectal cancer who underwent curative intent surgery between January 2014 and December 2016 were included for the final analysis. Skeletal muscle area (SMA), skeletal muscle radiodensity (SMD), visceral fat area (VFA) and mesorectal fat area (MFA) were retrospectively measured using preoperative CT images. To standardize the area according to patient stature, SMA was divided by the square of the height (m2) and the skeletal muscle mass index (SMI, cm2/m2) was obtained. Each median values of the distribution in male and female served as cut-off point for SMI, SMD, VFA, and MFA, respectively. Univariate and multivariate analysis were performed to evaluate the association between body composition and long-term oncological outcomes. Overall survival (OS) measured in months from the day of primary surgery until death for any cause. Disease-free survival (DFS) was defined as the interval between surgery and tumor recurrence. The Kaplan-Meier method with log-rank testing was used to validate prognostic biomarkers. Intraclass correlation coefficient (ICC) was used to evaluate interobserver and intraobserver reproducibility for SMA, SMD, MFA,VFA.ResultsDuring the follow-up period, 42 (27.1%) patients had tumor recurrence; 21 (13.5%) patients died. The sex-specific median value of SMI was 28.6 cm2/m2 for females and 48.2 cm2/m2 for males. The sex-specific median value of SMD was 34.7 HU for females and 37.4 HU for males. The sex-specific median value of VFA was 123.1 cm2 for females and 123.2 cm2 for males. The sex-specific median value of MFA was 13.8 cm2 for females and 16.0 cm2 for males. In the Cox regression multivariate analysis, SMI (P = 0.036), SMD (P = 0.022), and postoperative complications grades (P = 0.042) were significantly different between death group and non-death group; SMD (P = 0.011) and MFA (P = 0.022) were significantly different between recurrence group and non-recurrence group. VFA did not show any significant differences. By the Kaplan-Meier method with log-rank testing, DFS was significantly longer in patients with high-MFA (P = 0.028) and shorter in patients with low-SMD (P = 0.010), OS was significantly shorter in patients with low-SMI (P = 0.034) and low-SMD (P = 0.029).ConclusionsQuantitative evaluation of skeletal muscle mass and adipose tissue distributions at initial diagnosis were important predictors for long-term oncologic outcomes in RC patients. SMD and SMI were independent factors for predicting OS in patients with middle and low rectal cancer who had radical surgery. SMD and MFA were independent factors for predicting DFS in patients with middle and low rectal cancer who had radical surgery.

Body composition abnormalities are prognostic markers in several types of cancer, including colorectal cancer (CRC). Using our data distribution on body composition assessments and classifications could improve clinical evaluations and support population-specific opportune interventions. This study aimed to evaluate the distribution of body composition from computed tomography and assess the associations with overall survival among patients with CRC. In this multicenter cohort study, patients (N = 635) aged 18 years and older with CRC were observed for 12 to 36 months to assess outcomes. Skeletal muscle area (SM) and index (SMI), skeletal muscle radiodensity (SMD), intermuscular adipose tissue (IMAT), subcutaneous adipose tissue (SAT), and visceral adipose tissue (VAT) were evaluated, and classified based on tertile distributions. Low muscle mass (SMI) and poor muscle composition (SMD) were independent predictors of mortality regardless of follow-up period. This risk of mortality increased to more than 3-fold when combining both low SMI and low SMD (HRadjusted 3.1, 95% CI 1.8 to 5.4, respectively). Our study indicates that body composition characteristics may vary across countries, highlighting the need for developing sex- and population-specific cutoff values for computed tomography assessments in patients with different types of cancer.

Recent findings have spotlighted sarcopenia as a critical factor exacerbating cardiovascular risk in dialysis patients. However, no studies have investigated the relationship of muscle characteristics with thoracic aortic calcification (TAC). We explored whether skeletal muscle radiodensity (SMD) and skeletal muscle index (SMI) are associated with TAC in dialysis patients. In this study, 2517 dialysis patients (between January 2020 and June 2023) from four centres with chest computed tomography (CT) scans were analysed cross-sectionally. A cohort of 544 initial-dialysis patients (between January 2014 and December 2020) was followed for TAC progression. Chest CT images were used to assess SMD and SMI at the L1 level, as well as to measure the scores of TAC, including ascending TAC (ATAC), aortic arch calcification (AoAC) and descending TAC (DTAC). Multivariable linear regression models were employed to assess the effects of SMD and SMI on TAC and its progression. Restricted cubic spline was used to assess the potential non-linear relationships of SMD and SMI with TAC progression. The mean (SD) age for the cross-sectional study was 54.8 (14.0) years, with males accounting for 58.2%. Over a mean (SD) follow-up duration of 3.45 (1.82) years, 85.7% showed TAC progression. Comparing the highest quartile of SMD to the lowest quartile, a significant inverse association was observed with TAC (β, -1.08 [-1.42 to -0.75]; p < 0.001); similar trends were noted for SMI (β, -0.42 [-0.74 to -0.10]; p = 0.011). SMD and SMI as continuous variables were also both significantly negatively correlated with TAC. In the longitudinal study, multivariable linear regression models revealed that an increase of 1 SD in SMD resulted in a decrease of 0.10 SD (95% CI, -0.17 to -0.02; p = 0.011) in TAC progression, and an increase of 1 SD in SMI resulted in a decrease of 0.12 SD (95% CI, -0.20 to -0.04; p = 0.003) in TAC progression. Restricted cubic spline models excluded non-linear trends for the relationships of SMD and SMI with TAC progression. The associations of SMD and SMI with DTAC were consistent with those observed for TAC, but neither showed a significant association with ATAC. Higher SMD and higher SMI were significantly associated with lower TAC and its progression in dialysis patients. Improving SMD and SMI could be a new approach for reducing TAC.

Phase angle as a marker for muscle abnormalities and function in patients with colorectal cancer

This study investigates the prognostic value of skeletal muscle index (SMI) and skeletal muscle radiodensity (SMD) measured by chest CT in relation to all-cause and cardiovascular disease (CVD) mortality among hemodialysis (HD) patients. A retrospective study was conducted from January 2015 to December 2021 involving HD patients at a dialysis center. Chest CT scans at the twelfth thoracic vertebra level (T12) were analyzed to assess SMI and SMD. Sex-specific cut-off values for two metrics were determined using maximally selected rank statistics. Hazard ratios (HRs) were calculated to evaluate the associations of SMI and SMD with mortality. The discrimination of prognostic models was also compared. The study included 603 patients with a median age of 58years. Of these, 187 (31.0%) patients with SMI < 30.00 cm2/m2 (male) or < 25.04 cm2/m2 (female) and 192 (31.8%) patients with SMD < 32.25 HU (male) or < 30.64 HU (female) were categorized as lower SMI and SMD, respectively. Over a median follow-up of 3.8years, 144 deaths occurred. Multivariate Cox regression analysis showed that lower SMI and SMD were independently associated with all-cause mortality (SMI: HR = 1.47, 95% CI 1.03-2.10; SMD: HR = 1.75, 95% CI 1.20-2.54) and CVD mortality (SMI: HR = 1.74, 95% CI 1.03-2.94; SMD: HR = 1.72, 95% CI 1.02-2.95). Adding SMI and SMD to the established risk model improved the C-index from 0.82 to 0.87 (P < 0.001). Decision curve analysis showed that the prognostic model incorporating both SMI and SMD offered the highest net benefit for predicting all-cause mortality. Muscle metrics derived from CT scans at T12 level provide valuable prognostic information which could enhance the role of chest CT in muscle assessment among HD patients.