Skeletal Muscle Area Research Articles

High visceral adipose tissue area is independently associated with early allograft dysfunction in liver transplantation recipients: a propensity score analysis

ObjectivesTo evaluate the association between adipose tissue distribution and early allograft dysfunction (EAD) in liver transplantation (LT) recipients.MethodsA total of 175 patients who received LT from April 2015 to September 2020 were enrolled in this retrospective study. The areas of abdominal adipose tissue and skeletal muscle of all patients were measured based on the preoperative CT images. The appropriate statistical methods including the propensity score-matched (PSM) analysis were performed to identify the association between adipose tissue distribution and EAD.ResultsOf 175 LT recipients, 55 patients (31.4%) finally developed EAD. The multivariate logistic analysis revealed that preoperative serum albumin (odds ratio (OR) 0.34, 95% confidence interval (CI) 0.17–0.70), platelet–lymphocyte ratio (OR 2.35, 95% CI 1.18–4.79), and visceral adipose tissue (VAT) area (OR 3.17, 95% CI 1.56–6.43) were independent associated with EAD. After PSM analysis, VAT area was still significantly associated with EAD (OR 3.95, 95% CI 1.16–13.51). In survival analysis, no significant difference was identified in one-year graft failure (log-rank: p = 0.487), and conversely result was identified in overall survival (OS) (log-rank: p = 0.012; hazard ratio (HR) 4.10, 95% CI 1.27–13.16).ConclusionsLT recipients with high VAT area have higher risk for the occurrence of EAD, and high VAT area might have certain clinical value for predicting the poor OS of patients. For LT candidates with large amount of VAT, the clinicians can take clinical interventions by suggesting physical and nutritional treatments to improve outcomes after LT.

CT-derived body composition measurements as predictors for neoadjuvant treatment tolerance and survival in gastroesophageal adenocarcinoma.

Treatment for gastroesophageal adenocarcinomas can result in significant morbidity and mortality. The purpose of this study is to supplement methods for choosing treatment strategy by assessing the relationship between CT-derived body composition, patient, and tumor features, and clinical outcomes in this population. Patients with neoadjuvant treatment, biopsy-proven gastroesophageal adenocarcinoma, and initial staging CTs were retrospectively identified from institutional clinic encounters between 2000 and 2019. Details about patient, disease, treatment, and outcomes (including therapy tolerance and survival) were extracted from electronic medical records. A deep learning semantic segmentation algorithm was utilized to measure cross-sectional areas of skeletal muscle (SM), visceral fat (VF), and subcutaneous fat (SF) at the L3 vertebra level on staging CTs. Univariate and multivariate analyses were performed to assess the relationships between predictors and outcomes. 142 patients were evaluated. Median survival was 52months. Univariate and multivariate analysis showed significant associations between treatment tolerance and SM and VF area, SM to fat and VF to SF ratios, and skeletal muscle index (SMI) (p = 0.004-0.04). Increased survival was associated with increased body mass index (BMI) (p = 0.01) and increased SMI (p = 0.004). A multivariate Cox model consisting of BMI, SMI, age, gender, and stage demonstrated that patients in the high-risk group had significantly lower survival (HR = 1.77, 95% CI = 1.13-2.78, p = 0.008). CT-based measures of body composition in patients with gastroesophageal adenocarcinoma may be independent predictors of treatment complications and survival and can supplement methods for assessing functional status during treatment planning.

Perspectives on Sarcopenia as a Predictor for Outcomes in Pediatric Patients with Chronic Liver Disease.

Sarcopenia, a pathologic deficiency of muscle mass and function, has emerged as an important secondary feature of many chronic disease states. For adults with end stage liver disease, there are multiple mechanisms which contribute to sarcopenia and its presence has proven to be an important predictor of morbidity and mortality. In children, there are only a limited number of reports which investigate the role of sarcopenia in liver disease. These studies, which are discussed and summarized in this review, report small, single-center analyses with dissimilar study cohorts and varying clinical definitions. Still, children meeting the study entry criteria have sarcopenia with a reported prevalence of 24–70%. When assessed, sarcopenia appears to be associated with more severe disease but is independent of the Pediatric End-Stage Liver Disease (PELD) score and does not correlate with age, gender, or traditional anthropometric measures such as weight, height, weight-for-height, or body mass index (BMI). While individual studies may identify sarcopenia as a statistically significant risk factor for certain post-transplant outcomes such as longer ICU stay, longer duration of intubation, repeat operation, development of serious infection, longer hospital stay, death, or long-term growth failure, such associations are not consistently replicated across studies. Finally, although various methods of muscle mass quantification are utilized, the most reported is the total psoas muscle surface area (tPMSA) on computed tomography. This method, along with others such as skeletal muscle area and skeletal muscle index, have had normative values recently defined and these collective efforts should enable researchers a common basis of comparison when delineating sarcopenia, and its impact, across various study populations in future investigations – including in children with liver disease.

Impact of Preoperative Muscle Mass Maintenance and Perioperative Muscle Mass Loss Prevention After Pancreatectomy: Association Between Perioperative Muscle Mass and Postoperative Nutritional Status.

We investigated how preoperative sarcopenia and perioperative muscle mass changes affect postoperative nutritional parameters in patients undergoing pancreatectomy. This study included 164 patients undergoing pancreatectomy between January 2011 and October 2018. Skeletal muscle area was measured by computed tomography before and 6 months after surgery. Sarcopenia was defined as the lowest sex-specific quartile, and patients with muscle mass ratios less than -10% were classified into the high-reduction group. We examined the relationship between perioperative muscle mass and postoperative nutritional parameters 6 months after pancreatectomy. There were no significant differences in nutritional parameters between the sarcopenia and nonsarcopenia groups at 6 months after surgery. In contrast, albumin (P < 0.001), cholinesterase (P < 0.001), and prognostic nutritional index (P < 0.001) were lower in the high-reduction group. According to each surgical procedure, albumin (P < 0.001), cholinesterase (P = 0.007), and prognostic nutritional index (P < 0.001) were lower in the high-reduction group of pancreaticoduodenectomy. In distal pancreatectomy cases, only cholinesterase (P = 0.005) was lower. Postoperative nutritional parameters were correlated with muscle mass ratios but not with preoperative sarcopenia in patients undergoing pancreatectomy. Improvement and maintenance of perioperative muscle mass are important to maintain good nutritional parameters.

Artificial intelligence for predicting five-year survival in stage IV metastatic breast cancer patients: A focus on sarcopenia and other host factors.

We developed an artificial intelligence (AI) model that can predict five-year survival in patients with stage IV metastatic breast cancer, mainly based on host factors and sarcopenia. From a prospectively built breast cancer registry, a total of 210 metastatic breast cancer patients were selected in a consecutive manner using inclusion/exclusion criteria. The patients’ data were divided into two categories: a group that survived for more than 5 years and a group that did not survive for 5 years. For the AI model input, 11 features were considered, including age, body mass index, skeletal muscle area (SMA), height-relative SMA (H-SMI), height square-relative SMA (H2-SMA), weight-relative SMA (W-SMA), muscle mass, anticancer chemotherapy, radiation therapy, and comorbid diseases such as hypertension and mellitus. For the feature importance analysis, we compared classifiers using six different machine learning algorithms and found that extreme gradient boosting (XGBoost) provided the best accuracy. Subsequently, we performed the feature importance analysis based on XGBoost and proposed a 4-layer deep neural network, which considered the top 10 ranked features. Our proposed 4-layer deep neural network provided high sensitivity (75.00%), specificity (78.94%), accuracy (78.57%), balanced accuracy (76.97%), and an area under receiver operating characteristics of 0.90. We generated a web application for anyone to easily access and use this AI model to predict five-year survival. We expect this web application to be helpful for patients to understand the importance of host factors and sarcopenia and achieve survival gain.

Sarcopenia measurements and clinical outcomes in Crohn's disease surgical patients.

Patients with Crohn's disease (CD) have a high likelihood of being sarcopenic. Several studies have shown a positive correlation between sarcopenia measured as skeletal muscle index (SMI) and poor surgical outcomes in patients with CD. Our primary aim was to correlate SMI with the psoas muscle index (PMI), an easier measurement of sarcopenia. Secondary aim was to correlate SMI and PMI with clinical outcomes in a cohort of CD patients requiring surgery. A retrospective cohort study of CD patients who underwent surgery at a public health service from January 2010 to December 2019. Using computed tomography and magnetic resonance enterography studies, skeletal muscle area was measured at the third lumbar vertebra level. SMI and PMI were calculated and correlated. Correlation between SMI and PMI with surgical outcomes was performed. Seventy-six patients were included. Median length of stay (LOS) was 6 days (IQR, 5 to 9). Eleven patients (14.5%) required ICU admission, nine patients (11.8%) required TPN and thirteen patients (17.1%) had complications. The prevalence of sarcopenia was 63.2% based on the SMI threshold of 52.4 and 38.5cm2 /m2 for men and women, respectively. A positive correlation between SMI and PMI was found (r= 0.72, P< 0.0001). Sarcopenia status based on reported thresholds for SMI and for PMI showed no significant correlation with outcomes (LOS, ICU admission and complications). SMI and PMI show good correlation but there is insufficient evidence to suggest that sarcopenia status using either measurement has a significant impact on predicting clinical outcomes.

290. ANALYTIC MORPHOMIC INDEX AND QUANTITATIVE GASTRIC PERFUSION ASSESSMENT FOR RISK STRATIFICATION OF ANASTOMOTIC LEAKS FOLLOWING ESOPHAGECTOMY

Abstract Sarcopenia, a reduction in muscle mass, has been considered a preoperative risk factor for complications after esophagectomy while impaired perfusion of the gastric conduit has been associated with anastomotic leaks. The aim of this study was to stratify patients by their risk of anastomotic leak following esophagectomy using morphomic factors and quantitative assessment of gastric conduit perfusion. Patients who underwent an esophagectomy with a cervical anastomosis and gastric conduit from 2015–2021 were included. Preoperative CT scans were processed using semiautomated algorithms (MATLAB; MathWorks, MA). Indocyanine green perfusion was assessed intraoperatively (SPY elite; Stryker, MI). Sarcopenia was defined using skeletal muscle area (Martin’s criteria). Decreased subcutaneous fat, decreased bone mineral density, and impaired conduit perfusion were defined as below the cutoff value from the ROC curve. The morphomic index was determined using the number of decreased morphomic factors present (0–3). The Fisher exact test, the Mann–Whitney U test, and multivariable logistic regression were used to make statistical comparisons. 140 patients with both perfusion and morphomic data were evaluated (Leak n = 27; No leak n = 113). Decreased subcutaneous fat, decreased bone mineral density, and impaired gastric conduit perfusion were associated with an anastomotic leak (p = 0.041, 0.017, and 0.010). Neoadjuvant chemoradiation was significantly more common in the leak group (p = 0.048). On multivariable analysis, a higher morphomic Index and impaired gastric perfusion were risk factors for anastomotic leak. The incidence of anastomotic leaks with a high morphomic index (2 or 3) and impaired gastric perfusion was 40.6% compared to 9.4% with a low morphomic index and without impaired gastric perfusion (p = 0.006). Impaired gastric conduit perfusion and decreased preoperative subcutaneous fat area, bone mineral density, and skeletal muscle area, likely surrogates for increased frailty and poor nutritional status, were associated with an increased risk of anastomotic leaks especially when multiple morphomic factors were simultaneously decreased. These findings may be useful in risk stratification and intraoperative decision making in patients undergoing esophagectomy.

High blood urea nitrogen to creatinine ratio is associated with increased risk of sarcopenia in patients with chronic obstructive pulmonary disease

Background and aimsSarcopenia has been reported to be a prognostic factor for chronic obstructive pulmonary disease (COPD). However, the relationship between the ratio of blood urea nitrogen to creatinine (BUN/Cr) and sarcopenia in patients with COPD remain unclear. Therefore, the purpose of this study is to explore whether the ratio can be used as a predictor of sarcopenia in hospitalized COPD patients. MethodsThe skeletal muscle area index (SMI) at the level of the 12th thoracic vertebra (T12) was used to assess the risk of sarcopenia in patients. This single center cross-sectional study was conducted by analyzing the clinical parameters and identifying the T12 skeletal muscle area (SMA) and density (SMD) on chest CT images of COPD hospitalized patients admitted to the respiratory department of our hospital from March 2018 to August 2021. The study enrolled 265 hospitalized patients. Based on the different statistical properties of the above variables, differences between groups were measured by independent sample Student t-tests, Mann-Whitney U tests, or Chi-Square tests. Multivariable linear regression analysis was used to evaluate the relationship between the value of BUN/Cr and the risk of sarcopenia. ResultsThe serum BUN/Cr ratio was negatively correlated with SMI (r = −0.201, p = 0.001) in COPD patients, and multivariate linear regression analysis showed that this ratio was associated with the risk of sarcopenia (β = −0.109, p = 0.041). The optimal cut-off value of BUN/Cr ratio for identifying COPD patients with sarcopenia was 97.893. There was also a significant negative correlation between serum BUN/Cr ratio and forced vital capacity (FVC; r = −0.235, p < 0.001) and forced expiratory volume in the first second (FEV1; r = −0.219, p < 0.001). ConclusionThe BUN/Cr ratio can be used to predict sarcopenia and evaluate pulmonary function in hospitalized COPD patients.

Effects of muscle quantity and bone mineral density on injury and outcomes in older adult motor vehicle crash occupants

Objectives: Quantify the independent and combined effects of abdominal muscle quantity and lumbar bone mineral density (BMD) on injury risk and in-hospital outcomes in severely injured motor vehicle crash (MVC) occupants ages 50 and older. Methods: Skeletal muscle area measurements of MVC occupants were obtained through semi-automated segmentation of an axial computed tomography (CT) slice at the L3 vertebra. An occupant height-normalized Skeletal Muscle Index (SMI) was calculated - a defining metric of sarcopenia and low muscle mass (sarcopenia thresholds: <38.5 cm2/m2 females; <52.4 cm2/m2 males). Lumbar BMD was obtained using a validated, phantomless CT calibration method (osteopenia threshold: <145 mg/cm3). SMI and BMD values were used to categorize occupants, and logistic regression was used to associate sarcopenia, osteopenia, and osteosarcopenia predictors to injury outcomes (e.g., Injury Severity Score (ISS), maximum Abbreviated Injury Scale (MAIS) score, fractures) and hospital outcomes (e.g., length of stay, ICU days). Results: Of the 336 occupants, 210 (63%) were female (mean ± SD: age 66.3 ± 10.6). SMI was 41.7 ± 8.0 cm2/m2 in females and 51.2 ± 10.8 cm2/m2 in males. Based on SMI, 40% of females and 55% of males were classified as sarcopenic. BMD was 163.2 ± 38.3 mg/cm3 in females and 164.1 ± 35.4 mg/cm3 in males, with 41% of females and 33% of males classified as osteopenic. Prevalence of both conditions (osteosarcopenia) was similar between females (21%) and males (22%). Incidence of low SMI and BMD increased with age. Sarcopenic individuals were less likely to sustain a MAIS 2+ thorax injury and had longer ICU stays. Osteopenic individuals were more likely to sustain upper extremity injuries and fractures, and were less likely to be discharged to a rehabilitation facility. Osteosarcopenic individuals were less likely to be ventilated or admitted to the ICU but tended to spend more time on the ventilator if placed on one. Conclusions: Osteosarcopenia was not associated with any injury outcomes, but sarcopenia was associated with thoracic injury and osteopenia was associated with upper extremity injury incidence. Sarcopenia was only associated with ICU length of stay, while osteopenia was only associated with discharge destination. Osteosarcopenia was associated with likelihood of being ventilated, being admitted to the ICU, and with increased length of ventilation.

Development and validation of a nomogram to predict anastomotic leakage in colorectal cancer based on CT body composition.

BackgroundAnastomotic leakage (AL) is one of the most serious postoperative complications. This study aimed to investigate the predictive value of preoperative body composition for AL in patients with colorectal cancer (CRC).MethodsWe first reviewed data from 3,681 patients who underwent radical CRC resection 2013–2021 in our hospital, and 60 patients were diagnosed with AL after surgery. We designed a nested case-control study and two controls were randomly selected for each case according to the time and position of surgery. Body composition was measured at the level of the third lumbar vertebra based on computed tomography (CT) images. The risk factors of AL were analyzed by univariate and multivariate analysis. Nomogram was built using binary regression analysis and assessed for clinical usefulness, calibration, and discrimination.ResultsIn the multivariate analysis, gender, blood glucose, nutrition risk screening (NRS), skeletal muscle area (SMA) and visceral fat area (VFA) were independent risk factors for developing anastomotic leakage after surgery. The prognostic model had an area under the receiver operating characteristic curve of 0.848 (95% CI, 0.781–0.914). The calibration curve showed good consistency between the predicted and observed outcomes. Decision curve analysis indicated that patients with colorectal cancer can benefit from the prediction model.ConclusionsThe nomogram that combined with gender, blood glucose, NRS, SMA, and VFA had good predictive accuracy and reliability to AL. It may be conveniently for clinicians to predict AL preoperatively and be useful for guiding treatment decisions.

Impact of body composition and genotype on haemodynamics during surgery for pheochromocytoma and paraganglioma.

Maintaining intraoperative haemodynamic stability can reduce cardiovascular complications during surgery for pheochromocytoma and paraganglioma (PPGL). Risk factors such as tumour size and catecholamine levels are reported to predict haemodynamic responses during surgery for PPGL. We hypothesized that additional factors including body composition and genetic information could further improve prediction. Consecutive patients with PPGL confirmed by surgical pathology between June 2010 and June 2019 were retrospectively included. Cross-sectional computed tomography images at the L3 level were used to assess body composition parameters including skeletal muscle area and visceral fat area. Next-generation sequencing was performed using a panel containing susceptibility genes of PPGL. Differences in clinical-genetic characteristics and body composition parameters were analysed and compared in patients with and without intraoperative haemodynamic instability (HDI). We included 221 patients with PPGL (median age 47 [38-56] years, and 52% male). Among them, 49.8% had Cluster 2 mutations (related to kinase signalling pathways), 44.8% had sarcopenia, and 52.9% experienced intraoperative HDI. Compared with patients without HDI, more patients with HDI had Cluster 2 mutations (59.8% vs. 38.5%, P=0.002) and less had sarcopenia (35.9% vs. 54.8%, P=0.005). Multivariate analysis showed that urine vanillylmandelic acid≥58μmol/day (adjusted odds ratio [OR]=1.840, 95% confidence interval [CI]=1.012-3.347, P=0.046), tumour size≥4cm (adjusted OR=2.278, 95% CI=1.242-4.180, P=0.008), and Cluster 2 mutations (adjusted OR=2.199, 95% CI=1.128-4.285, P=0.021) were independent risk factors for intraoperative HDI, while sarcopenia (adjusted OR=0.475, 95% CI=0.266-0.846, P=0.012) decreased the risk. Body composition and genotype were associated with intraoperative haemodynamics in patients with PPGL. Our results indicated that inclusion of body composition and genotype in the overall assessment of patients with PPGL helped to predict HDI during surgery, which could assist in implementing preoperative and intraoperative measures to reduce perioperative complications.

Serum creatinine/cystatin C ratio is a systemic marker of sarcopenia in patients with gastrointestinal stromal tumours.

BackgroundIt is well known that sarcopenia is a common risk factor in patients with gastrointestinal tumours, which may negatively affect the clinical outcome and prognosis. Recent studies suggest that serum creatinine-cystatin C (Cr/CysC) ratio may be associated with sarcopenia, but this association lacks sufficient evidence in patients with gastrointestinal stromal tumours (GIST). Therefore, this study aimed to investigate whether the Cr/CysC ratio was associated with sarcopenia and recurrence-free survival (RFS) in patients with GIST.Materials and methodsThe study retrospectively analysed 413 patients with GIST who underwent surgical resection from January 2016 to January 2020. The serum Cr/CysC ratio was determined as a proxy for sarcopenia by comparing it with various biomarkers and Cox multifactorial analysis was used to determine the relationship between Cr/CysC ratio and prognosis.ResultsSerum Cr/CysC was positively correlated with skeletal muscle area (SMA) (r = 0.256, p < 0.001), skeletal muscle index (SMI) (r = 0.300, p < 0.001), and hand grip strength (HGS) (r = 0.251, p < 0.001). The area under the receiver operator characteristic curve for sarcopenic subjects with serum Cr/CysC ratio was significantly greater than other biomarkers (Cr/CysC: 0.840, CysC: 0.732, Cr: 0.518). The optimal cut-off value for Cr/CysC was 0.65, and patients in the high Cr/CysC group had a higher 3-year recurrence-free survival (RFS) than those in the low Cr/CysC group (92.72 vs. 72.46%, p < 0.001). Cox multifactorial analysis found that the Cr/CysC ratio was an independent risk factor for RFS in GIST patients (HR = 2.143, 95% CI: 1.431–5.459, p = 0.011).ConclusionSerum Cr/CysC ratio has satisfactory and comparable diagnostic accuracy, and prognostic value for sarcopenia in patients with GIST. Therefore, it can be a simple and practical clinical tool to screen sarcopenia in GIST patients. However, further studies are required to validate these findings.

Body composition from single versus multi-slice abdominal computed tomography: Concordance and associations with colorectal cancer survival.

Computed tomography (CT) scans are routinely obtained in oncology and provide measures of muscle and adipose tissue predictive of morbidity and mortality. Automated segmentation of CT has advanced past single slices to multi-slice measurements, but the concordance of these approaches and their associations with mortality after cancer diagnosis have not been compared. A total of 2871 patients with colorectal cancer diagnosed during 2012-2017 at Kaiser Permanente Northern California underwent abdominal CT scans as part of routine clinical care from which mid-L3 cross-sectional areas and multi-slice T12-L5 volumes of skeletal muscle (SKM), subcutaneous adipose (SAT), visceral adipose (VAT) and intermuscular adipose (IMAT) tissues were assessed using Data Analysis Facilitation Suite, an automated multi-slice segmentation platform. To facilitate comparison between single-slice and multi-slice measurements, sex-specific z-scores were calculated. Pearson correlation coefficients and Bland-Altman analysis were used to quantify agreement. Cox models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for death adjusting for age, sex, race/ethnicity, height, and tumour site and stage. Single-slice area and multi-slice abdominal volumes were highly correlated for all tissues (SKM R=0.92, P<0.001; SAT R=0.97, P<0.001; VAT R=0.98, P<0.001; IMAT R=0.89, P<0.001). Bland-Altman plots had a bias of 0 (SE: 0.00), indicating high average agreement between measures. The limits of agreement were narrowest for VAT ( 0.42 SD) and SAT ( 0.44 SD), and widest for SKM ( 0.78 SD) and IMAT ( 0.92 SD). The HRs had overlapping CIs, and similar magnitudes and direction of effects; for example, a 1-SD increase in SKM area was associated with an 18% decreased risk of death (HR=0.82; 95% CI: 0.72-0.92), versus 15% for volume from T12 to L5 (HR=0.85; 95% CI: 0.75-0.96). Single-slice L3 areas and multi-slice T12-L5 abdominal volumes of SKM, VAT, SAT and IMAT are highly correlated. Associations between area and volume measures with all-cause mortality were similar, suggesting that they are equivalent tools for population studies if body composition is assessed at a single timepoint. Future research should examine longitudinal changes in multi-slice tissues to improve individual risk prediction.

Sarcopenia does not predict outcome in patients with CNS lymphoma undergoing systemic therapy.

Low skeletal muscle mass as a proxy parameter for sarcopenia acts as a non-invasive imaging marker that is associated with poor prognosis in numerous types of cancer. The present study aimed to assess the influence of body composition parameters on overall survival (OS) and progression free survival (PFS) in patients diagnosed with primary central nervous system lymphoma (PCNSL). A total of 98 patients with PCNSL treated at University Hospital Magdeburg (Magdeburg, Germany) from 2013–2019 were retrospectively studied. Patients with a pre-treatment staging computed tomography (CT) scan that included the third lumbar vertebra were reviewed for analysis. Skeletal muscle area (SMA), skeletal muscle index (SMI), mean muscle density and skeletal muscle gauge (SMG) were measured on the CT scan prior to treatment. Parameters were associated with OS and PFS. Overall, 72 patients were included in the present study. Results of the present study demonstrated that the median OS was 10 months (range, 1–181 months), and 37 patients (51.4%) presented with sarcopenia. Moreover, the median OS was 7 months in the sarcopenic group and 32 months in the non-sarcopenic group. Results of the present study further illustrated that SMI, SMA, density and SMG did not exert a significant effect on OS. Notably, the median PFS was 2.5 months in the low SMI group and 10 months in the normal SMI group. Body composition parameters did not exert a significant effect on PFS. Overall, the results of the present study demonstrated that sarcopenia was not a risk factor for decreased OS or PFS in patients with PCNSL undergoing systemic treatment.

Prevalence of Low Muscle Mass in the Computed Tomography at the Third Lumbar Vertebra Level Depends on Chosen Cut-Off in 200 Hospitalised Patients-A Prospective Observational Trial.

Measuring skeletal muscle area (SMA) at the third lumbar vertebra level (L3) using computed tomography (CT) is increasingly popular for diagnosing low muscle mass. The aim was to describe the effect of the CT L3 cut-off choice on the prevalence of low muscle mass in medical and surgical patients. Two hundred inpatients, who underwent an abdominal CT scan for any reason, were included. Skeletal muscle area (SMA) was measured according to Hounsfield units on a single CT scan at the L3 level. First, we calculated sex-specific cut-offs, adjusted for height or BMI and set at mean or mean-2 SD in our population. Second, we applied published cut-offs, which differed in statistical calculation and adjustment for body stature and age. Statistical calculation of the cut-off led to a prevalence of approximately 50 vs. 1% when cut-offs were set at mean vs. mean-2 SD in our population. Prevalence varied between 5 and 86% when published cut-offs were applied (p < 0.001). The adjustment of the cut-off for the same body stature variable led to similar prevalence distribution patterns across age and BMI classes. The cut-off choice highly influenced prevalence of low muscle mass and prevalence distribution across age and BMI classes.

An improved method to assess skeletal muscle mass in patients with liver cirrhosis based on computed tomography images.

Conventionally, the skeletal muscle area with computed tomography (CT) attenuation ranging from -29 to +150 Hounsfield unit (HU) divided by height squared (the conventional skeletal muscle index [SMI]) was used as an index of skeletal muscle mass. However, it includes fat-infiltrated skeletal muscle, which is known to have poor function. This study aims to determine whether the low-fat SMI, which uses skeletal muscle mass with CT attenuation ranging from +30 to +150 HU, or conventional SMI appropriately reflects the function of skeletal muscle. We retrospectively analyzed 120 patients with cirrhosis whose handgrip strength was measured. Among them, 48 patients underwent a physical performance assessment such as liver frailty index (LFI) and short physical performance battery (SPPB), and 80 underwent quality of life (QOL) assessment. The relationships between each SMI and handgrip strength, LFI, SPPB, and QOL were evaluated. Low-fat SMI was significantly correlated with handgrip strength (males, R=0.393, p=0.002; females, R=0.423, p<0.001) and LFI (males, R=-0.535, p=0.035; females, R=-0.368, p=0.039), whereas conventional SMI was not. When using low-fat SMI, patients with low skeletal muscle mass had significantly low handgrip strength, LFI, SPPB, and physical and social-related QOL score than those without. By contrast, no significant differences were found for any items when using conventional SMI. Low-fat SMI is a good index of skeletal muscle mass that appropriately reflects skeletal muscle function.

Hybrid Exercise Program for Sarcopenia in Older Adults: The Effectiveness of Explainable Artificial Intelligence-Based Clinical Assistance in Assessing Skeletal Muscle Area.

Background: Sarcopenia is a geriatric syndrome characterized by decreased skeletal muscle mass and function with age. It is well-established that resistance exercise and Yi Jin Jing improve the skeletal muscle mass of older adults with sarcopenia. Accordingly, we designed an exercise program incorporating resistance exercise and Yi Jin Jing to increase skeletal muscle mass and reverse sarcopenia in older adults. Additionally, machine learning simulations were used to predict the sarcopenia status after the intervention. Method: This randomized controlled trial assessed the effects of sarcopenia in older adults. For 24 weeks, 90 older adults with sarcopenia were divided into intervention groups, including the Yi Jin Jing and resistance training group (YR, n = 30), the resistance training group (RT, n = 30), and the control group (CG, n = 30). Computed tomography (CT) scans of the abdomen were used to quantify the skeletal muscle cross-sectional area at the third lumbar vertebra (L3 SMA). Participants’ age, body mass, stature, and BMI characteristics were analyzed by one-way ANOVA and the chi-squared test for categorical data. This study explored the improvement effect of three interventions on participants’ L3 SMA, skeletal muscle density at the third lumbar vertebra (L3 SMD), skeletal muscle interstitial fat area at the third lumbar vertebra region of interest (L3 SMFA), skeletal muscle interstitial fat density at the third lumbar vertebra (L3 SMFD), relative skeletal muscle mass index (RSMI), muscle fat infiltration (MFI), and handgrip strength. Experimental data were analyzed using two-way repeated-measures ANOVA. Eleven machine learning models were trained and tested 100 times to assess the model’s performance in predicting whether sarcopenia could be reversed following the intervention. Results: There was a significant interaction in L3 SMA (p < 0.05), RSMI (p < 0.05), MFI (p < 0.05), and handgrip strength (p < 0.05). After the intervention, participants in the YR and RT groups showed significant improvements in L3 SMA, RSMI, and handgrip strength. Post hoc tests showed that the YR group (p < 0.05) yielded significantly better L3 SMA and RSMI than the RT group (p < 0.05) and CG group (p < 0.05) after the intervention. Compared with other models, the stacking model exhibits the best performance in terms of accuracy (85.7%) and F1 (75.3%). Conclusion: One hybrid exercise program with Yi Jin Jing and resistance exercise training can improve skeletal muscle area among older adults with sarcopenia. Accordingly, it is possible to predict whether sarcopenia can be reversed in older adults based on our stacking model.

Influence of the skeletal muscle index on pharmacokinetics and toxicity of fluorouracil.

The body composition of patients has been associated with tolerability and effectiveness of anticancer therapy. This study aimed to assess the influence of the skeletal muscle index (SMI) on the pharmacokinetics and toxicity of fluorouracil. Patients treated in an oncological practice with fluorouracil-based chemotherapy and undergoing therapeutic drug monitoring were retrospectively investigated. Computed tomography images were analyzed to measure abdominal skeletal muscle areas in Hounsfield units for the psoas major muscle, back and total skeletal muscle to determine the SMI. For the latter, an automated segmentation method was used additionally. SMI measures were tested as covariates on fluorouracil clearance in a population pharmacokinetic model. Furthermore, regression analyses were performed to analyze the influence of SMI measures on the probability of clinically relevant adverse events (CTCAE grades ≥ 2). Fluorouracil plasma concentrations of 111 patients were available. Covariate analyses showed significant improvements of the model fit by all SMI measures. However, interindividual variability of fluorouracil clearance was only slightly reduced, whereas the SMI of the back muscle showed the largest reduction (-1.1 percentage points). Lower SMI values of the back muscle increased the probability for polyneuropathy and lower SMI of the psoas increased the probability for fatigue. Our results suggest that pharmacokinetics and toxicity of fluorouracil may be associated with specific SMI measures which deserve further investigation.

Inflammation and Loss of Skeletal Muscle Mass in Chronic Limb Threatening Ischemia

Lower extremity peripheral arterial disease (PAD) is an atherosclerotic disease of the lower extremities. Atherosclerosis, inflammation, and sarcopenia are independently associated and potentiate each other. Inflammation is deeply involved in the formation and progression of atherosclerosis and is also involved in the pathophysiology of sarcopenia. Sarcopenia is defined as low muscle mass, with low muscle strength. This study aims to determine the differences in skeletal muscle characteristics and in inflammatory parameters between patients with claudication and with chronic limb threatening ischemia (CLTI). An observational, prospective study in patients with PAD was conducted from January 2018 to December 2020. The clinical characteristics and the cardiovascular risk factors were prospectively registered. The inflammatory parameters determined were: positive acute phase proteins (C-reactive Protein- CRP- and fibrinogen) and negative acute phase proteins albumin, total cholesterol and high-density lipoprotein (HDL). The skeletal muscle area and density were quantified with a computed topography (CT) scan. The strength was determined with a Jamar® hydraulic hand dynamometer. A total of 116 patients (mean age: 67.65±9.53 years-old) 64% with claudication and 46% with CLTI were enrolled in the study. No differences were registered between patients with claudication and CLTI on age, cardiovascular risk factors (hypertension, dyslipidemia, diabetes mellitus, and smoking habits) and medication. There was a higher prevalence of men in the claudication group (88.89% vs. 71.70%, P=0.019). Analyzing the inflammatory parameters, we noted that patients with CLTI had increased serum levels of positive acute phase proteins: CRP (37.53±46.61mg/L vs. 9.18±26.12mg/L, P=0.000), and fibrinogen (466.18±208.07mg/dL vs. 317.37±79.42mg/dL, P=0.000). CLTI patients had decreased negative acute phase proteins: albumin (3.53±0.85g/dL vs. 3.91±0.72g/dL, P=0.001), total cholesterol (145.41±38.59mg/dL vs. 161.84±34.94mg/dL, P=0.013) and HDL (38.70±12.19mg/dL vs. 51.31±15.85mg/dL, P=0.000). We noted that patients with CLTIhad lower skeletal muscle area and mass (14,349.77±3,036.60mm2 vs. 15,690.56±3,183.97mm2P=0.013; 10.11±17.03HU vs. 18.02±13.63HU P=0.013). After adjusting for the variable sex, the association between skeletal muscle density and CLTI persisted (r (97)=-0.232, P=0.021). The groups did not differ in strength (patients with claudication: 25.39±8.23 Kgf vs. CLTI: 25.17±11.95 Kgf P=0.910). CLTI patients have decreased skeletal muscle mass and a systemic inflammation status. Recognizing the deleterious triad of atherosclerosis, inflammation and loss of skeletal mass patients with CLTI is an opportunity to improve medical therapy and to perform a timely intervention to stop this vicious cycle.

Assesment of relationship between sarcopenia and vascular calcification in patients with severe aortic stenosis

Background and Aims : Sarcopenia is a progressive disorder involving the accelerated loss of muscle mass and function. Sarcopenia becomes more frequent by ageing. Sarcopenia is associated with inflammation and increased risk for coronary artery disease. Sarcopenia may be diagnosed by several techniques including measurement of spinal muscle area in computed tomography (CT) images. We aimed to evaluate relationship between sarcopenia and vascular calcification in patients scheduled for TAVR.Methods: All of the patients who underwent CT for TAVR planning between 2013 and 2020 were screened and skeletal muscle area at L3 vertebrae level was measured. Parameters regarding vascular calcification were also measured from CT images.View Large Image Figure ViewerDownload Hi-res image Download (PPT)Conclusions: Sarcopenia is an important marker of vascular calcification and it may be measured easily from CT images performed for any indication. MAC and all-cause mortality rate during follow-uo are more frequent in patients with sarcopenia. Background and Aims : Sarcopenia is a progressive disorder involving the accelerated loss of muscle mass and function. Sarcopenia becomes more frequent by ageing. Sarcopenia is associated with inflammation and increased risk for coronary artery disease. Sarcopenia may be diagnosed by several techniques including measurement of spinal muscle area in computed tomography (CT) images. We aimed to evaluate relationship between sarcopenia and vascular calcification in patients scheduled for TAVR. Methods: All of the patients who underwent CT for TAVR planning between 2013 and 2020 were screened and skeletal muscle area at L3 vertebrae level was measured. Parameters regarding vascular calcification were also measured from CT images. Conclusions: Sarcopenia is an important marker of vascular calcification and it may be measured easily from CT images performed for any indication. MAC and all-cause mortality rate during follow-uo are more frequent in patients with sarcopenia.