Skeletal Muscle Area Research Articles

Validation of bedside ultrasound to predict lumbar muscle area in the computed tomography in 200 non-critically ill patients: The USVALID prospective study

Skeletal muscle area (SMA) in the computed tomography (CT) at the third lumbar vertebra (L3) level is a proxy for whole-body muscle mass but is only performed for clinical reasons. Ultrasound is a promising tool to determine muscle mass at the bedside. It is still unclear how well ultrasound and which ultrasound measuring points can predict CT L3 SMA. This prospective observational trial included 200 non-critically ill patients, who underwent an abdominal CT scan for any clinical reason within 48h before the ultrasound examination. Ultrasound muscle thickness was evaluated at 3 measuring points on the thigh and 2 measuring points on the upper arm with minimal compression. On the CT scan, the entire L3 SMA was measured based on Hounsfield units. Using a model selection algorithm based on the Bayesian information criterion (BIC) and clinical considerations, a linear prediction model for CT L3 SMA based on the ultrasound muscle thickness and other independent variables was fitted and assessed with cross-validation. 67,5% and 32,5% of the patients were from surgical and medical wards, respectively. Mean ultrasound muscle thickness values were between 2,2 and 3,6cm on the thigh and between 1,4 and 2,8cm on the upper arm. All ultrasound muscle thickness values were higher in men than in women (P<0,05). CT L3 SMA was 40cm2 higher in men than in women (P<0,001). The final prediction model for CT L3 SMA included the following 4 independent variables: ultrasound muscle thickness at the ventral measuring point of the thigh in the short-axis plane, sex, weight, and height. It had a similar BIC (BIC of 1515) compared to larger models with 6-8 independent variables including multiple ultrasound measuring points (BIC of 1506-1519). Additional clinical considerations to choose the final model were less time consumption when measuring a single ultrasound measuring point and better anatomical overview at the short-axis plane. The final model predicted CT L3 SMA with a R2 of 0,74 (P<0,001) and a cross-validated R2 of 0,65. One single ultrasound measuring point at the thigh together with sex, height and weight very well predicts CT L3 SMA across different clinical populations. Ultrasound is a safe and bedside method to measure muscle thickness longitudinally to monitor the effects of nutrition and physical therapy.

Muscle Area and Density Assessed by Abdominal Computed Tomography in Healthy Adults: Effect of Normal Aging and Derivation of Reference Values.

A growing body of evidence has demonstrated the prognostic value of skeletal muscle area and quality measured by computed tomography (CT) as biomarkers of sarcopenia and frailty. However, there exists little data in normal healthy subjects to inform reference values and determine the effects of advancing age and sex on CT muscle parameters. Abdominal CT images of patients (20-80 years of age) presenting to the emergency department with benign abdominal symptoms and no significant medical comorbidities were retrospectively collected from 2014 to 2017. Psoas and abdominal wall muscle area (PMA, WMA) and density (PMD, WMD) at the level of the L4 vertebrae were measured with the CoreSlicer.com web app. The normal reference range was computed by non-parameteric 2.5th and 97.5th percentiles stratified by sex and restricted by age to the younger subgroup (20-39 years of age). The cohort consisted of 390 otherwise healthy patients (162 males, 228 females). The lower reference range for PMA was <22.0 cm2 in males and <11.1 cm2 in females, and for WMA was <112.2 cm2 in males and <75.6 cm2 in females. There was a graded decline observed in PMA and WMA among older compared to younger adults (especially ≥60 years of age) (P<0.001) and among females compared to males (P<0.001). There was also a graded decline observed in PMD and WMD among older compared to younger adults (P<0.001), irrespective of sex. This study has defined the normal reference values and age-associated down-trend for CT muscle parameters at L4 in a healthy population using an accessible web-based software, which help contextualize and interpret these imaging biomarkers of sarcopenia in clinical care.

Low muscle mass determined by psoas muscle area does not correlate with dual-energy x-ray absorptiometry or total lumbar muscle mass scores: A prospective cohort study of patients undergoing vascular surgery.

Background/Objective: Low muscle mass and sarcopenia have been explored as risk factors for poor outcomes following vascular surgery. The findings have been variable. The use of a diverse range of techniques to identify low muscle mass is a confounder in establishing the true relationship between low muscle mass, sarcopenia and outcomes. Our aim was to establish if different scoring methods identified the same patients as sarcopenic. We also explored which method best predicted outcomes. Method: 70 patients undergoing vascular surgery were prospectively assessed for sarcopenia using dual-energy x-ray absorptiometry (DEXA) scan, grip strength and gait speed. These patients underwent abdominal CT imaging as routine care. The muscle mass of each patient was determined using DEXA and by both psoas muscle and total skeletal muscle area on CT, normalised for patient height (PMI and CT-SMI, respectively). Low muscle mass was defined by published age- and sex-specific cut-offs. Grip strength data was combined with muscle mass to define sarcopenic patients. One- and 3-year mortality and time to readmission was recorded. Conclusion and Results: 10-22% of patients had low muscle mass and 4-10% of patients were sarcopenic, depending on the method employed. PMI did not correlate with DEXA or CT-SMI for low muscle mass, but CT-SMI correlated with DEXA (p = 0.0007). For sarcopenia, CT-SMI and DEXA scoring correlated (p = 0.002); PMI correlated with CT-SMI (p = 0.0006) but not DEXA. Low muscle mass by PMI predicted 1-year mortality (p = 0.02, X2 = 5.34, Effect size = 1.04) but the applicability of this finding is limited by the diverse pathologies explored. No other method predicted 1- or 3-year mortality or readmissions in this heterogenous cohort. The psoas area did not correlate with muscle mass defined by DEXA or total lumbar skeletal muscle area. Low psoas muscle index may be an independent marker of poor outcome, unrelated to generalised sarcopenia, and this warrants investigation in specific pathologies. A lower total number of patients were sarcopenic than had been expected, emphasising the need to use population-based pre-defined cut-offs.

Body composition assessment: comparison of quantitative values between magnetic resonance imaging and computed tomography

The primary objective of this study was to compare measurements of skeletal muscle index (SMI), visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) at the level of L3, on subjects who underwent computed tomography (CT) and magnetic resonance imaging (MRI) examinations within a three-month period. The secondary objective was to compare the automatic and semi-automatic quantifications of the same values for CT images. Among subjects who underwent CT and MRI at our Institution between 2011 and 2020, exclusion criteria were: presence of extensive artifacts; images not including the whole waist circumference; CT acquired with low-dose technique and lack of non-contrast images. A set of three axial images (CT, MRI T1-weighted and T2-weighted) were used to extract the following measurements with semi-automatic segmentations: SMI [calculated normalizing skeletal muscle area (SMA) by the square height], SAT, VAT. For the CT images only, the same values were also calculated by using automatic segmentation. Statistical analysis was performed comparing quantitative MRI and CT measurements by Pearson correlation analysis and by Bland-Altman agreement analysis. A total of 123 patients were included. By performing linear regression analysis, CT and MRI measurements of SMI showed a high correlation (r2=0.81 for T1, r2=0.89 for T2), with a mean logarithmic difference between CT and MRI quantitative values of 0.041 for T1-weighted and 0.072 for T2-weighted images. CT and MRI measurements of SAT showed high correlation (r2=0.81 for T1; r2=0.81 for T2), with a mean logarithmic difference between CT and MRI values of 0.0174 for T1-weighted and 0.201 for T2-weighted images. CT and MRI measurements of VAT showed high correlation (r2=0.94 for T1; r2=0.93 for T2), with a mean logarithmic difference of 0.040 for T1-weighted and -0.084 for T2-weighted images. The comparison of values extracted by semi-automatic and automatic segmentations were highly correlated. Quantification of body composition values at MRI from T1-weighted and T2-weighted images was highly correlated to same values at CT, therefore quantitative values of body composition among patients who underwent either one of the examinations may be compared. CT body composition values extracted by semi-automatic and automatic segmentations showed high correlation.

The effect of skeletal muscle area and attenuation in patients with sternum fracture due to blunt chest trauma.

This study aims to retrospectively investigate the imaging features of patients with sternum fracture (SF) and concomitant organ injuries. We also aimed to evaluate the potential prognostic effect of skeletal muscle area (TMA) and muscle attenuation (MuA) values. Computed tomography (CT) images of patients with SF were re-evaluated by two observers (Observer-1 and 2). Observer-3 has measured TMA and MuA values. Observer-1 has repeated the measurements blindly to the first measurement results to evaluate the inter-observer agreement. The length of hospital stay, death, hemiplegia, or quadriplegia were investigated from the archives. Mann-Whitney U-test or Student's t-test was used to investigate the relationship between linear variables. The intraclass correlation coefficient (ICC) score was used to evaluate the interobserver agreement. Logistic regression analysis was used to estimate the relative effect of variables by calculating unadjusted odds ratios (ORs) for categorical outcomes. Sixty-five patients had SF and 53 patients had SF and concomitant organ injuries. The most common injuries accompanying SF were rib fracture (73.58%) and lung contusion (60.38%). Manubrium fracture was the most common fracture location (52.3%), and 18 patients (27.7%) had displaced SF. Eight patients (15.1%) were discharged with plegia and five (9.4%) died. Hemothorax, displaced SF and decreased MuA were predictors of prolonged hospital stay, and the presence of cardiac contusion, displaced SF, hemothorax, and vertebra body fracture were independent factors for death. The presence of a displaced SF and decreased MuA value are important prognostic factors in patients with SF.

Agreement between muscle mass assessments by computed tomography and calf circumference in patients with cancer: A cross-sectional study.

Cancer influences body composition, including a loss of muscle mass (MM), associated with worse outcomes. The study aimed to evaluate the agreement between MM estimated by calf circumference (CC) and computed tomography (CT) image as a reference method. A cross-sectional study including patients (>20 years) diagnosed with cancer attending a reference center of oncology. Spearman's correlation was performed to verify the correlation between CC and MM by CT, including skeletal muscle area - SMA and skeletal muscle index - SMI. ROC curves, Kappa coefficient, sensitivity, specificity, positive and negative predictive values were obtained. The study included 219 patients, age 62.9±13.1 years (mean±standard deviation). Low CC was observed in 43.8% of the patients, and 29.2% had low SMI. CC positively correlated with SMA (rho=0.333) and SMI (rho=0.329), and fair agreements (K=0.268) were observed between CC and SMI, with higher and significant values for males (K=0.332) and patients below 60 years (K=0.419). The area under the curve (AUC) for low CC to identifying low SMI was equal to 0.685 (CI 95% 0.606-0.765). Low CC presented fair agreement to identify low SMI in the sample; however, the negative predictive value was almost 80% for all analyses. Low CC is not a surrogate for low SMI in patients with cancer, but it could be an alternative, non-invasive, easy-to-perform method to pre-screen patients with cancer with adequate SMI.

Low Skeletal Muscle Area at the T12 Paravertebral Level as a Prognostic Marker for Community-Acquired Pneumonia

This study aimed to investigate whether the dorsal skeletal muscle area at 12th thoracic level (T12SMA) could be used as a predictor of in-hospital mortality and long-term survival among patients with community-acquired pneumonia (CAP). A retrospective study was conducted on 1701 CAP patients who underwent chest computed tomography (CT) examinations at the First Hospital of Qinhuangdao. The primary outcome was in-hospital mortality. The T12SMA was analyzed. Multivariate regression logistic models were constructed to identify the prognostic markers of hospital mortality. Cox regression logistic models were constructed to identify the risk factors of long-term survival. The multiple logistic regression analysis showed that T12SMA [odds ratio (OR)=0.946; p=0.007], CURB-65 (OR=1.521; p=0.008), creatinine (OR=1.003; p=0.001), albumin (OR=0.908; p=0.001) and intensive care unit (ICU) (OR=2.715; p=0.007) were independent risk factors for predicting the in-hospital mortality. The cox regression logistic analysis showed that T12SMA (OR=0.968; p=0.000), age (OR= 1.036; p=0.000), sex (OR= 1.435; p=0.002), CURB-65 (OR=1.311; p=0.000), albumin (OR=0.952; p=0.000), creatinine (OR=1.002; p=0.000) and ICU (OR=1.606; p=0.001) were prognostic markers of long-term survival. T12SMA, CURB-65, creatinine, albumin and ICU were independent risk factors for in-hospital mortality among patients with CAP. And low T12SMA affected the in-hospital mortality and long-term survival of patients with CAP.

Impact of visceral adipose tissue on long-term outcomes after gastrectomy for advanced gastric cancer

ObjectivesThe aim of this study was to examine the effects of a decrease in visceral adipose tissue on the long-term outcomes of patients with gastric cancer after surgery. MethodsThis single-institution, retrospective study included a cohort of 485 patients who underwent gastrectomy for P-T2 (MP; or a more advanced gastric cancer) from April 2008 to April 2018. The preoperative visceral adipose tissue area and the skeletal muscle area were measured on computed tomography images. The areas were divided by height (m2) to obtain the visceral adipose tissue index (VAI) and skeletal muscle mass index (SMI). ResultsOf the 485 patients, 243 (50.1%) were in the low-VAI group and 242 (49.9%) were in the high-VAI group. For overall survival, the low-VAI group, compared with the high-VAI group, had a significantly poorer prognosis (P < 0.001). Multivariate analysis indicated that both low VAI (hazard ratio [HR], 1.666; 95% confidence interval [CI], 1.127–2.461; P = 0.010) and low SMI (HR, 1.467; 95% CI, 1.057–2.035; P = 0.022) were independent prognostic factors. ConclusionBoth loss of preoperative skeletal muscle mass and a decrease in visceral adipose tissue have an effect on the long-term outcomes of advanced gastric cancer.

Impact of Body Composition During Neoadjuvant Chemoradiotherapy on Complications, Survival and Tumor Response in Patients With Locally Advanced Rectal Cancer.

BackgroundTo explore the impact of body composition before neoadjuvant chemoradiotherapy (pre-NCRT) and after neoadjuvant chemoradiotherapy (post-NCRT) on complications, survival, and tumor response in patients with locally advanced rectal cancer (LARC).MethodsPatients with LARC who underwent radical surgery after NCRT between Ja 22nuary 2012 and March 2019 were studied. Body composition parameters, including skeletal muscle area (SMA), muscle density (MD), visceral fat area (VFA), total abdominal fat area (TAFA), and subcutaneous fat area (SFA), was identified at the third lumbar vertebra level on computed tomography (CT). The patients were divided into two groups based on the sex-specific quartile values of SMA, MD, VFA, TAFA, SFA, and body composition change. Patient characteristics, short- and long-term postoperative complications, survival, and tumor response were analyzed.ResultsA total of 122 eligible patients were enrolled. Body composition parameters, except MD, were strongly correlated with BMI (p < 0.001). Pre-NCRT low MD (p = 0.04) and TAFA loss (p = 0.02) were significantly correlated with short- and long-term ileus, respectively. Pre-NCRT low SMA was a significant prognostic factor for both disease-free survival (DFS) (HR 2.611, 95% CI 1.129–6.040, p = 0.025) and cancer-specific survival (CSS) (HR 3.124, 95% CI 1.030–9.472, p = 0.044) in the Cox regression multivariate analysis. Multivariate logistic regression analysis identified post-NCRT SFA (OR 3.425, 95% CI 1.392–8.427, p = 0.007) and SFA loss (OR 3.358, 95% CI 1.214–9.289, p = 0.02) as independent risk factors for tumor regression grade (TRG) and downstaging, respectively.ConclusionPre-NCRT low MD and TAFA loss were related to a high incidence of short- and long-term ileus, respectively. Pre-NCRT low SMA was a significant prognostic factor for CSS and DFS. Post-NCRT SFA and SFA loss were independent risk factors for TRG and downstaging, respectively.

A reliable and robust method for the upper thigh muscle quantification on computed tomography: toward a quantitative biomarker for sarcopenia

BackgroundWe aimed to evaluate the feasibility of the upper thigh level as a landmark to measure muscle area for sarcopenia assessment on computed tomography (CT).MethodsIn the 116 healthy subjects who performed CT scans covering from mid-abdomen to feet, the skeletal muscle area in the upper thigh level at the inferior tip of ischial tuberosity (SMAUT), the mid-thigh level (SMAMT), and L3 inferior endplate level (SMAL3) were measured by two independent readers. Pearson correlation coefficients between SMAUT, SMAMT, and SMAL3 were calculated. Inter-reader agreement between the two readers were evaluated using intraclass correlation coefficient (ICC) and Bland-Altman plots with 95% limit of agreement (LOA).ResultsIn readers 1 and 2, very high positive correlations were observed between SMAUT and SMAMT (r = 0.91 and 0.92, respectively) and between SMAUT and SMAL3 (r = 0.90 and 0.91, respectively), while high positive correlation were observed between SMAMT and SMAL3 (r = 0.87 and 0.87, respectively). Based on ICC values, the inter-reader agreement was the best in the SMAUT (0.999), followed by the SMAL3 (0.990) and SMAMT (0.956). The 95% LOAs in the Bland-Altman plots indicated that the inter-reader agreement of the SMAUT (− 0.462 to 1.513) was the best, followed by the SMAL3 (− 9.949 to 7.636) and SMAMT (− 12.105 to 14.605).ConclusionMuscle area measurement at the upper thigh level correlates well with those with the mid-thigh and L3 inferior endpoint level and shows the highest inter-reader agreement. Thus, the upper thigh level might be an excellent landmark enabling SMAUT as a reliable and robust biomarker for muscle area measurement for sarcopenia assessment.

Dietary Alaska Pollack Protein Induces Acute and Sustainable Skeletal Muscle Hypertrophy in Rats

Our previous studies suggested that Alaska pollack protein (APP) intake increases skeletal muscle mass and that it may cause a slow-to-fast shift in muscle fiber type in rats fed a high-fat diet after 56 days of feeding. In this study, we explored whether dietary APP induces acute and sustainable skeletal muscle hypertrophy in rats fed a normal-fat diet. Male 5-week-old Sprague–Dawley rats were divided into four groups and fed a purified ingredient-based high-fat diet or a purified ingredient-based normal-fat diet with casein or APP, containing the same amount of crude protein. Dietary APP significantly increased gastrocnemius muscle mass (105~110%) after 2, 7 days of feeding, regardless of dietary fat content. Rats were separated into two groups and fed a normal-fat diet with casein or APP. Dietary APP significantly increased gastrocnemius muscle mass (110%) after 56 days of feeding. Dietary APP significantly increased the cross-sectional area of the gastrocnemius skeletal muscle and collagen-rich connective tissue after 7 days of feeding. It decreased the gene expression of Mstn /Myostatin, Trim63/MuRF1, and Fbxo32/atrogin-1, but not other gene expression, such as serum IGF-1 after 7 days of feeding. No differences were observed between casein and APP groups with respect to the percentage of Type I, Type IIA, and Type IIX or IIB fibers, as determined by myosin ATPase staining after 7 days of feeding. In the similar experiment, the puromycin-labeled peptides were not different between dietary casein and APP after 2 days of feeding. These results demonstrate that APP induces acute and sustainable skeletal muscle hypertrophy in rats, regardless of dietary fat content. Dietary APP, as a daily protein source, may be an approach for maintaining or increasing muscle mass.

P139 Body composition and Crohn’s disease behavior: Is adiposity the main game changer?

Abstract Background Introduction: Visceral fat has been associated with unfavorable outcomes in Crohn’s disease (CD) patients. We investigated the association between body composition upon diagnosis and complicated phenotypes and time until surgery in patients with CD. Methods retrospective cohort study including patients with CD who had a computed tomography enterography (CT) or an entero magnetic resonance (MR) performed within 6 months of diagnosis. Skeletal muscle, visceral and subcutaneous adipose tissue cross-sectional areas were determined with CT or MR images at L3 vertebrae level, after being processed with Slice-o-Matic (Tomovison) and ABCS module (applicable only to CT scan images). Logistic regression was used to assess predictors of disease behaviourand time until abdominal urgery was modeled with proportional hazards Cox models. Results We included 63 patients: 33(52%) men with median age of 35 years. Disease location and behaviour according to Montreal classification was as follows: L1=28(44%), L2=13(21%), L3=18(28%), L1+L4=1(2%), L3+L4=3(5%); B1=39(62%), B2=11(17%), B3=13(21%); 20(32%) patients had perianal disease. At diagnosis, 17(27%) patients were treated with corticosteroids. Anti-TNF agents were started in 8(13%) patients, azathioprine in 23(36%), combination therapy in 15(24%); 17(27%) patients did not start any medical therapy. Visceral obesity was present in 12(19%) patients at diagnosis. Visceral obesity was associated with higher age of CD onset (median 60 vs 34 years, p=0.002) and complicated disease behaviour(B2/B3) at diagnosis (66.7% vs 31.7%, p=0.021), with an approximately 4 times higher risk of complicated behaviour(OR=4.37, 95%IC=1.19–18.44, p=0.03).After adjusting for age and perianal disease, total adipose tissue (visceral and subcutaneous fat) remained statistically significant and was associated with a 4% increase in the odds of complicated behaviourat diagnosis per 10 cm2of total adipose tissue (OR 1.004,95%CI 1.00–1.008, p=0.043). Median follow-up time was 3.35 years, during which 15 (24%) of patients underwent abdominal surgery. Visceral obesity was associated with a 5.10 times higher risk of abdominal surgery during follow-up (95%CI 1.52–17.09, p=0.008); after adjusting to disease behaviour, visceral obesity maintained a near significant association with a 2.90 times higher risk of surgery (95%CI 0.83–10.08, p=0.09). Conclusion In our cohort of patients with newly diagnosed CD, total fat upon diagnosis seems to be associated with B2 and B3 disease phenotypes. Furthermore, visceral obesity was associated with a 5.10 times higher risk of abdominal surgery during follow-up and with a shorter time until surgery.

Normative values of skeletal muscle indices for nutritional assessment and implications on definition of sarcopenia in Indian adult population.

Sarcopenia is defined as both low muscle function (performance or strength) and low muscle mass. Although aging is the main cause of sarcopenia, it can also occur due to poor nutrition and chronic diseases like liver cirrhosis, chronic kidney disease, and diabetes. To do the quantitative analysis of various normative skeletal muscle indices (to define sarcopenia) in the Indian population. Sex-specific means, standard deviations (SD), and sarcopenia cutoffs (mean-2SD) of psoas muscle thickness (PMTH), psoas muscle area (PMA), psoas muscle index (PMI), erector spinae muscle area (ESMA), skeletal muscle radiation attenuation (SMRA), total skeletal muscle area (SMA), and total skeletal muscle index (SMI) were computed. A total of 2002 individuals (1308 males and 694 females) underwent CT evaluation. PMTH (mm/m) was observed to be 15.87±2.67 in males vs. 12.61±2.46 in females (p=0.0001); PMA (cm2) was 18.55±3.45 in males vs.13.52±2.80 in females (p=0.0001); PMI (cm2/m2) was 6.69±1.40 in males vs. 5.57±1.18 in females (p=0.0001); ESMA (cm2) was 45.74±6.01 in males vs. 35.37±5.63 in females (p=0.0001); ESMI (cm2/m2) was 16.5±2.55 in males vs. 14.62±2.6 in females (p=0.0001); SMRA was 55.80±3.91 Hounsfield unit (HU) in males vs. 52.36±3.67 HU in females (p=0.0001); SMA (cm2) was 147.73±11.77 in males vs. 106.33±12.00 in females (p=0.0001); and SMI (cm2/m2) was estimated to be 51.00±5.70 in males vs. 43.93±6.05 in females (p=0.0001). PMTH, PMI, ESMI, SMI, and SMRA cutoffs for sarcopenia at L3 were observed to be 10.53 mm/m, 3.89 cm2/m2, 11.40 cm2/m2, 39.59 cm2/m2, and 47.98 HU among males and 7.69, 3.20, 9.42, 31.83, and 45.01 among females, respectively; these values wereconsistent with previously reported cutoffs in Indian studies but not consistent with the cutoffs reported in other countries. Normative values of skeletal muscle indices for either sex among the Indian adult population would enable future studies on sarcopenia in various medical conditions.

Serum creatinine/cystatin C ratio as a surrogate marker for sarcopenia in patients with gastric cancer

BackgroundSarcopenia is an age-related syndrome that may have negative impact on surgical outcomes and long-term survival of patients with gastric cancer. Serum creatinine/cystatin C (Cr/CysC) ratio has attracted attention as a surrogate marker for sarcopenia but has not been adequately studied in patients with gastric cancer. The purpose of this study was to investigate the validity of serum Cr/CysC ratio as a predictor of sarcopenia, evaluate a statistical cut-off value, and assess the relationship between Cr/CysC ratio and prognosis of patients with gastric cancer.MethodsWe retrospectively studied 327 patients who underwent surgery for gastric cancer from June 2009 to October 2021. The skeletal muscle mass index was calculated using computed tomography (CT). We determined the relevance of serum Cr/CysC ratio as a surrogate maker for sarcopenia by comparing it with various biomarkers. The Concordance index (C-index) was calculted to measure whether the Cr/CysC ratio can prognosis of patients with gastric cancer.ResultsSerum Cr/CysC was significantly correlated with with Skeletal Muscle Index (SMI) (r = 0.221, p < 0.001) and Skeletal Muscle Area (SMA) (r = 0.258, p < 0.001). The area under the curve for sarcopenia was significantly larger for serum Cr/CysC ratio than for other biomarkers (Cr/CysC: 0.644, CysC: 0.535, Cr: 0.556). Patients in the high-Cr/CysC group have longer survival time than that in low-Cr/CysC group, defined by the cutoff value 0.67. The C-index of both Cr/CysC ratio and SMI with OS was 0.63.ConclusionsSerum Cr/CysC ratio can be used accurately, inexpensively, and easily to evaluate sarcopenia in male patients with gastric cancer. Our study shows that patients with Cr/CysC below 0.67 had possibility of sarcopenia and would be poor prognosis.

Low muscle mass and early hospital readmission post-kidney transplantation.

Patients exhibiting features of frailty and sarcopenia increasingly are presenting for kidney transplantation (KT) assessment. Sarcopenia, when ascertained by radiological measures, is associated with a higher transplant waiting list mortality; but studies on post-operative outcomes are lacking. We aimed to determine the clinical significance of low muscle mass in chronic kidney disease (CKD) patients subsequently receiving KT. We retrospectively analyzed 63 patients with Stage 4-5 CKD who, between 2012 and 2020, had undergone abdominal computed tomography (CT) scanning up to 2years before KT. The degree of skeletal muscle loss was assessed using the total cross-sectional skeletal muscle area at the third lumbar vertebral level (L3). Cox proportional-hazards regression and Frailty models were used to identify risk factors for early hospital readmission post KT. Thirty-four patients (54%) displayed low muscle mass, which was independently associated with a lower serum creatinine and phosphate, lower body mass index, lower mean muscle attenuation of the L3 cross-sectional area, and higher serum parathyroid hormone (for all p < 0.05). Deceased donor transplant recipients (n = 45) with low muscle mass demonstrated greater hospital readmissions within 30days of KT [adjusted hazard ratio (HR) = 4.24, 95% CI 1.40-12.90, p = 0.01]. Low muscle mass is highly prevalent in the pre-transplant CKD population and is associated with increased hospital readmission in the early post-transplant period.

Validation for measurements of skeletal muscle areas using low-dose chest computed tomography

Various methods were suggested to measure skeletal muscle areas (SMAs) using chest low-dose computed tomography (chest LDCT) as a substitute for SMA at 3rd lumbar vertebra level (L3-SMA). In this study, four SMAs (L1-SMA, T12-erector spinae muscle areas, chest wall muscle area at carina level, pectoralis muscle area at aortic arch level) were segmented semi-automatically in 780 individuals taking concurrent chest and abdomen LDCT for healthcare screening. Four SMAs were compared to L3-SMA and annual changes were calculated from individuals with multiple examinations (n = 101). Skeletal muscle index (SMI; SMA/height2) cut-off for sarcopenia was determined by lower 5th percentile of young individuals (age ≤ 40 years). L1-SMA showed the greatest correlation to L3-SMA (men, R2 = 0.7920; women, R2 = 0.7396), and the smallest annual changes (0.3300 ± 4.7365%) among four SMAs. L1-SMI cut-offs for determining sarcopenia were 39.2cm2/m2 in men, and 27.5cm2/m2 in women. Forty-six men (9.5%) and ten women (3.4%) were found to have sarcopenia using L1-SMI cut-offs. In conclusion, L1-SMA could be a reasonable substitute for L3-SMA in chest LDCT. Suggested L1-SMI cut-offs for sarcopenia were 39.2cm2/m2 for men and 27.5cm2/m2 for women in Asian.

Evaluation of skeletal muscle mass as a predictor of prognosis in patients treated in hospital for COVID-19 infection.

Skeletal muscle indexes are known to be one of the important prognostic indicators in many clinical situations. This study aims to evaluate the effects of laboratory values and muscle mass measures such as skeletal muscle area (SMA), skeletal muscle index (SMI), skeletal muscle density (SMD) and skeletal muscle gauge (SMG) obtained from the 12th thoracic vertebra (T12) level of patients hospitalized for COVID-19 infection on prognosis. The patients' age, comorbidity index (CCI) scores, gender, anthropometric criteria such as height, weight, and BMI, laboratory values, development of NIMV and IC need during follow-up, length of hospital stay, and hospital mortality were retrospectively screened. The relationship between clinical and laboratory variables, SMA, SMI, SMD, and SMG values, and patient outcomes such as the need for non-invasive mechanical ventilation (NIMV), need for intensive care, and mortality was investigated using multivariate logistic regression analysis. It was shown in multilinear regression analysis that T12SMD (β=-0.254; p=0.036), albumin (β=-0.465; p=0.005), and procalcitonin values (β=-0.292; p=0.026) were independent risk factors on mortality for intensive care in patients hospitalized due to COVID-19 infection. T12SMD has been shown to be significantly associated with various negative outcomes such as mortality, need for NIMV, and need for intensive care independently of body mass index (BMI) in our study (Tab. 5, Fig. 2, Ref. 25).

Prognostic impact of sarcopenia in patients with hepatocellular carcinoma treated with PD-1 inhibitor.

Sarcopenia is a progressive generalized loss of skeletal muscle mass commonly observed in advanced stages of cancer. To assess the relationship between sarcopenia and the prognosis of patients with hepatocellular carcinoma (HCC) treated with a programmed cell death 1 (PD-1) inhibitor. This is a retrospective study. This study included patients with HCC treated with camrelizumab between 1 March 2020 and 1 December 2021. The skeletal muscle area at the L3 vertebra middle level was used to calculate the skeletal muscle index. Propensity score matching (PSM) analysis was used to balance the variables between the two groups. In all, 97 patients with HCC were included in the study, with 46 and 51 patients in the sarcopenia group and the non-sarcopenia group, respectively. The baseline characteristics of albumin, Child-Pugh class, albumin-bilirubin score, neutrophil-to-lymphocyte ratio, and platelet-to-lymphocyte ratio were significantly different between the two groups. In total, 26 patients from each group (n = 52) were selected after the PSM analysis. The progression-free survival (PFS) in the non-sarcopenia group was significantly longer than that in the sarcopenia group before and after PSM analysis (6.5 versus 4.8 months, p = 0.038). In addition, the disease control rate was similar before and after PSM analysis (57.7% versus 69.2%, p = 0.388). The objective response rate in the non-sarcopenia group tended to be higher than that in the sarcopenia group (11.5% versus 30.8%, p = 0.090, after PSM), but no statistically significant difference was found. The median overall survival (OS) in the non-sarcopenia group tended to longer than it in the sarcopenia group before PSM without significant differences (16.3 versus 11.3 months, p = 0.090) and the median OS was similar between the two groups after PSM (16.3 versus 16.8 months, p = 0.735). HCC patients with sarcopenia tended to have higher levels of inflammation and lower levels of albumin than patients without sarcopenia. Sarcopenia is associated with a shorter PFS in HCC patients treated with PD-1 inhibitor.

Prognostic Value of Sarcopenia and Myosteatosis in Patients with Resectable Pancreatic Ductal Adenocarcinoma.

The clinical relevance of myosteatosis has not been well evaluated in patients with pancreatic ductal adenocarcinoma (PDAC), although sarcopenia has been extensively researched. Therefore, we evaluated the prognostic value of muscle quality, including myosteatosis, in patients with resectable PDAC treated surgically. We retrospectively evaluated 347 patients with resectable PDAC who underwent curative surgery (mean age ± standard deviation, 63.6 ± 9.6 years; 202 male). Automatic muscle segmentation was performed on preoperative computed tomography (CT) images using an artificial intelligence program. A single axial image of the portal phase at the inferior endplate level of the L3 vertebra was used for analysis in each patient. Sarcopenia was evaluated using the skeletal muscle index, calculated as the skeletal muscle area (SMA) divided by the height squared. The mean SMA attenuation was used to evaluate myosteatosis. Diagnostic cutoff values for sarcopenia and myosteatosis were devised using the Contal and O'Quigley methods, and patients were classified according to normal (nMT), sarcopenic (sMT), myosteatotic (mMT), or combined (cMT) muscle quality types. Multivariable Cox regression analyses were conducted to assess the effects of muscle type on the overall survival (OS) and recurrence-free survival (RFS) after surgery. Eighty-four (24.2%), 73 (21.0%), 75 (21.6%), and 115 (33.1%) patients were classified as having nMT, sMT, mMT, and cMT, respectively. Compared to nMT, mMT and cMT were significantly associated with poorer OS, with hazard ratios (HRs) of 1.49 (95% confidence interval, 1.00-2.22) and 1.68 (1.16-2.43), respectively, while sMT was not (HR of 1.40 [0.94-2.10]). Only mMT was significantly associated with poorer RFS, with an HR of 1.59 (1.07-2.35), while sMT and cMT were not. Myosteatosis was associated with poor OS and RFS in patients with resectable PDAC who underwent curative surgery.

Sarcopenia is the independent predictor of mortality in critically ill patients with cirrhosis

Sarcopenia is strongly associated with poor outcome in cirrhosis. There are little prospective data that sarcopenia influences outcomes in critically ill cirrhotics (CICs). Computed tomography (CT) is the gold standard for sarcopenia assessment in the intensive care unit (ICU), as it is independent of hydration status. This study aims to assess the prevalence of sarcopenia and study its impact on clinical outcomes in CICs. In this prospective observational study, CICs admitted to the liver ICU were enrolled, if meeting inclusion (age 18-70 years, abdominal CT scan within three months before ICU admission) and exclusion criteria (survival likely to be <24 h, coexisting chronic diseases). Clinical, hemodynamic, biochemical, and nutritional parameters, including length of stay (LOS), duration of mechanical ventilation (MV), development of new-onset infections (NOI), incidence of new-onset acute kidney injury (AKI), and overall survival, were recorded. CT images at the L3 level were analyzed using Slice-O-Matic V4.3 software to assess the skeletal muscle index (SMI) expressed as skeletal muscle area (cm2)/height (m2). Sarcopenia was defined if SMI was <50 cm2/m2 - males and <39 cm2/m2 - females. Data were analyzed using SPSS version 22. Altogether 111 patients (M-83.8%; age 48.4±11.3 years; etiology: Alcohol - 56 [50.5%], non-alcoholic steatohepatitis - 27 [24.3%], viral - 12 [10.8%], and others - 16 [14.4%]; Child-Turcotte-Pugh - 11.9±1.8; model for end-stage liver disease - 27.8±7.3; sequential organ failure assessment - 10.5±4.1; APACHE - 23±8; and MV - 54 [48.6%]) were enrolled. Of these, 76 (68.5%) were sarcopenic and 35 (31.5%) non-sarcopenic. Sarcopenic CICs had higher overall mortality (72.4%) compared to non-sarcopenics (40%) (P=0.001, OR [95% CI] - 3.93 [1.69-9.12]), and higher prevalence of sepsis at ICU admission (53.9% vs. 31.4%, P=0.027, OR [95% CI] - 1.7 [1.0-2.92]) than non-sarcopenics. LOS, duration of MV, incidence of NOI, and development of new-onset AKI were comparable between groups. Multivariate binary logistic regression showed that sarcopenia, sepsis, and APACHE II score were independently associated with mortality. Two-thirds of CICs have sarcopenia at ICU admission, making them 1.7 times more susceptible to sepsis and increasing the risk of mortality by almost 4-fold in the ICU. Almost 70% of patients with chronic liver disease admitted to the ICU have low muscle mass (sarcopenia). The presence of sarcopenia per se makes them highly prone to infections and increases the chances of death by almost 4-fold; thus, highlighting the importance of nutrition optimization in this patient group.