Skeletal muscle cutoff values for sarcopenia diagnosis using T10 to L5 measurements in a healthy US population

Prevalence and Impact of Computed Tomography-Defined Sarcopenia on Survival in Patients with Human Papillomavirus-Positive Oropharyngeal Cancer: A Systematic Review

Sarcopenia is a known independent prognostic factor for decreased survival in patients with head and neck cancer; yet, its importance for the growing number of younger patients diagnosed with human papillomavirus (HPV)-positive oropharyngeal carcinoma (OPC+) has not been established. This systematic literature review aimed to determine the prevalence and impact of computed tomography (CT)-defined sarcopenia on survival outcomes for adult OPC+ patients (>18 y) undergoing any treatment modality. Prospective studies were searched using PubMed, Embase, CENTRAL, CINAHL, and Web of Science up until and including February 2022. Bias was assessed using the Quality In Prognosis Studies (QUIPS) tool, and certainty of evidence using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) system. In total, 9 studies (total pooled OPC+ patients, n  = 744) were identified and included in this review; 2 at low, 6 at moderate, and 1 at high risk of bias. All studies varied in sarcopenia assessment methods and skeletal muscle index threshold cutoff values. These studies demonstrated the cumulative prevalence of sarcopenia for OPC+ patients to be 42.9% (95% CI: 37.8%, 47.9%). While overall survival (3 studies, n = 253) and progression-free survival (1 study, n = 117) was lower in sarcopenic OPC+ patients, this was not statistically significant. GRADE certainty of evidence for impact of pretreatment sarcopenia on overall survival was low and progression-free survival was very low. Although these studies showed there to be a high prevalence of pretreatment sarcopenia in patients with OPC+, which may decrease survival, the impact on progression-free survival is very uncertain. Further, high-quality research utilizing consistent sarcopenia definitions and assessment methods that are conducted specifically in OPC+ is required to strengthen evidence certainty and determine if sarcopenia is an independent prognostic factor for this population.

Age-specific reference values for low psoas muscle index at the L3 vertebra level in healthy populations: A multicenter study

BACKGROUND AND AIMS

The progressive and generalized loss of skeletal muscle mass, strength and physical function is defined as sarcopenia. Sarcopenia is closely related to the prognosis of patients. Accurate diagnosis and adequate management of sarcopenia are crucial. The psoas muscle mass index taken at the third lumbar vertebra (L3-PMI, cm2/m2) is one of the established methods for evaluating skeletal muscle mass. However, the cutoff values of L3-PMI for diagnosis of sarcopenia are not yet to be clarified in Asian populations. We attempted to establish reference values for low L3-PMI that would be suitable for defining sarcopenia in the Northern Chinese population.

METHODS

This was a retrospective, multicenter cross-sectional study. A search of abdominal CT imaging reports was conducted in four representative cities in northern China. Transverse CT images were measured using the analysis software Slice-O-Matic. Low psoas muscle index was defined as the 5th percentile or mean-2SD of the study group.

RESULTS

1,787 healthy individuals in the study were grouped by age. The sex and number of people in each group were similar. L3-PMI had a negative linear correlation with age, and a strong correlation with the skeletal muscle index taken at the third lumbar vertebrae (L3-SMI, cm2/m2). The L3-PMI reference values in males were 5.41 cm2/m2 for 20-29 years, 4.71 cm2/m2 for 30-39 years, 4.65 cm2/m2 for 40-49 years, 4.10 cm2/m2 for 50-59 years and 3.68 cm2/m2 for over 60 years by using 5th percentile threshold. Similarly, the reference values in females were 3.32, 3.40, 3.18, 2.91, and 2.62 cm2/m2. When using mean-2SD as the reference, the values for each age group were 4.57, 4.16, 4.03, 3.37, and 2.87 cm2/m2 for males and 2.79, 2.70, 2.50, 2.30, and 2.26 cm2/m2 for females, respectively.

CONCLUSION

We defined the reference values of age-specific low skeletal muscle mass when simply evaluated by L3-PMI. Further studies about the association of sarcopenia using these reference values with certain clinical outcomes or diseases are needed.

The association between lumbar paraspinal muscle functional cross-sectional area on MRI and regional volumetric bone mineral density measured by quantitative computed tomography

Osteosarcopenia is a common condition among elderly and postmenopausal female patients. Site-specific bone mineral density is more predictive of bone-related complications. Few studies have investigated muscle-bone associations. Our results demonstrated that in women, significant positive associations between paraspinal muscles FCSA and vBMD exist at different lumbosacral levels. These regional differences should be considered when interpreting bone-muscle associations in the lumbar spine.

INTRODUCTION

There is increasing evidence between bone and muscle volume associations. Previous studies have demonstrated comorbidity between osteoporosis and sarcopenia. Recent studies showed that sarcopenic subjects had a fourfold higher risk of concomitant osteoporosis compared to non-sarcopenic individuals. Although site-specific bone mineral density (BMD) assessments were reported to be more predictive of bone-related complications after spinal fusions than BMD assessments in general, there are few studies that have investigated level-specific bone-muscle interactions. The aim of this study is to investigate the associations between muscle functional cross-sectional area (FCSA) on magnetic resonance imaging (MRI) and site-specific quantitative computed tomography (QCT) volumetric bone mineral density (vBMD) in the lumbosacral region among spine surgery patients.

METHODS

We retrospectively reviewed a prospective institutional database of posterior lumbar fusion patients. Patients with available MRI undergoing posterior lumbar fusion were included. Muscle measurements and FCSA were conducted and calculated utilizing a manual segmentation and custom-written program at the superior endplate of the L3-L5 vertebrae level. vBMD measurements were performed and calculated utilizing a QCT pro software at L1-L2 levels and bilateral sacral ala. We stratified by sex for all analyses.

RESULTS

A total of 105 patients (mean age 61.5 years and 52.4% females) were included. We found that female patients had statistically significant lower muscle FCSA than male patients. After adjusting for age and body mass index (BMI), there were statistically significant positive associations between L1-L2 and S1 vBMD with L3 psoas FCSA as well as sacral ala vBMD with L3 posterior paraspinal and L5 psoas FCSA. These associations were not found in males.

CONCLUSIONS

Our results demonstrated that in women, significant positive associations between the psoas and posterior paraspinal muscle FCSA and vBMD exist in different lumbosacral levels, which are independent of age and BMI. These regional differences should be considered when interpreting bone and muscle associations in the lumbar spine.

Sarcopenia 'made simple' and outcomes from emergency laparotomy

BACKGROUND

Emergency Laparotomy (EL) is recognized as high-risk surgery with high mortality. Established surgical risk assessment tools (NELA Risk Prediction Calculator, P-POSSUM, ACS-NSQIP) are accurate predictors of morbidity and mortality. However, their multicomponent complexity limits their use in practice. Sarcopenia is associated with poorer surgical outcomes. This study tests for an association between a simple measure of radiological sarcopenia and mortality in EL patients in an Australian cohort.

METHODS

A retrospective analysis was conducted of 500 patients admitted to four Australian hospitals who underwent EL during 2016-2017. All patients had a contemporaneous abdomino-pelvic CT scan. Radiological sarcopenia was measured as the ratio of total psoas muscle area (PM) to L3 vertebral body cross sectional area (PM:L3). Patients were followed up to 12 months. Primary outcomes were 30-, 90- and 365-day mortality.

RESULTS

The mean 30-day mortality predictions for NELA, P-POSSUM and ACS-NSQIP were 11.36%, 17.28% and 11.30% respectively. PM:L3 ratio was associated with 30-, 90- and 365-day mortality (P < 0.001) and sex (P < 0.001) and negatively correlated with age (r = -0.4612; P < 0.001). Radiological sarcopenia had a weak negative correlation with NELA (r = -0.2737; P < 0.001), P-POSSUM (r = -0.1880; P < 0.001) and ACS-NSQIP (r = -0.2351; P < 0.001). The latter three metrics were significantly correlated (r > 0.5696; P < 0.001).

CONCLUSION

Radiological sarcopenia (CT-assessed PM:L3) is a significant predictor of mortality in EL patients in Australia. The results of this study suggest that radiological sarcopenia is equivalent to established risk assessment tools. The more timely and easily accessible CT-assessed PM:L3 metric is potentially automatable and may have significant utility in clinical practice.

Low muscle mass in COVID-19 critically-ill patients: Prognostic significance and surrogate markers for assessment

INTRODUCTION

Low muscle mass is a common condition in the critically ill population and is associated with adverse clinical outcomes. The primary aim of this study was to analyze the prognostic significance of low muscle mass using computed tomography (CT) scans in COVID-19 critically ill patients. A second objective was to determine the accuracy and agreement in low muscle mass identification using diverse markers compared to CT as the gold standard.

METHODS

This was a prospective cohort study of COVID-19 critically ill patients. Skeletal muscle area at the third lumbar vertebra was measured. Clinical outcomes (intensive care unit [ICU] and hospital length of stay [LOS], tracheostomy, days on mechanical ventilation [MV], and in-hospital mortality) were assessed. Phase angle, estimated fat-free mass index, calf circumference, and mid-upper arm circumference were measured as surrogate markers of muscle mass.

RESULTS

Eighty-six patients were included (mean age ± SD: 48.6 ± 12.9; 74% males). Patients with low muscle mass (48%) had a higher rate of tracheostomy (50 vs 20%, p = 0.01), prolonged ICU (adjusted HR 0.53, 95%CI 0.30-0.92, p = 0.024) and hospital LOS (adjusted HR 0.50, 95% CI 0.29-0.86, p = 0.014). Bedside markers of muscle mass showed poor to fair agreement and accuracy compared to CT-assessed low muscle mass.

CONCLUSION

Low muscle mass at admission was associated with prolonged length of ICU and hospital stays. Further studies are needed to establish targeted nutritional interventions to halt and correct the catabolic impact of COVID-19 in critically ill patients, based on standardized and reliable measurements of body composition.

Influence of reduced muscle mass and quality on ventilator weaning and complications during intensive care unit stay in COVID-19 patients

BACKGROUND & AIMS

Sarcopenia, a loss of muscle mass, quality and function, which is particularly evident in respiratory muscles, has been associated with many clinical adverse outcomes. In this study, we aimed at evaluating the role of reduced muscle mass and quality in predicting ventilation weaning, complications, length of intensive care unit (ICU) and of hospital stay and mortality in patients admitted to ICU for SARS-CoV-2-related pneumonia.

METHODS

This was an observational study based on a review of medical records of all adult patients admitted to the ICU of a tertiary hospital in Milan and intubated for SARS-CoV-2-related pneumonia during the first wave of the COVID-19 pandemic. Muscle mass and quality measurement were retrieved from routine thoracic CT scans, when sections passing through the first, second or third lumbar vertebra were available.

RESULTS

A total of 81 patients were enrolled. Muscle mass was associated with successful extubation (OR 1.02, 95% C.I. 1.00-1.03, p = 0.017), shorter ICU stay (OR 0.97, 95% C.I. 0.95-0.99, p = 0.03) and decreased hospital mortality (HR 0.98, 95% C.I. 0.96-0.99, p = 0.02). Muscle density was associated with successful extubation (OR 1.07, 95% C.I. 1.01-1.14; p = 0.02) and had an inverse association with the number of complications in ICU (Β -0.07, 95% C.I. -0.13 - -0.002, p = 0.03), length of hospitalization (Β -1.36, 95% C.I. -2.21 - -0.51, p = 0.002) and in-hospital mortality (HR 0.88, 95% C.I. 0.78-0.99, p = 0.046).

CONCLUSIONS

Leveraging routine CT imaging to measure muscle mass and quality might constitute a simple, inexpensive and powerful tool to predict survival and disease course in patients with COVID-19. Preserving muscle mass during hospitalisation might have an adjuvant role in facilitating remission from COVID-19.

Sarcopenia as a Prognostic Marker in Elderly Head and Neck Squamous Cell Carcinoma Patients Undergoing (Chemo-)Radiation

Sarcopenia is associated with reduced survival and increased toxicity in malignant diseases. The prevalence of sarcopenia increases with age and is an important cause of functional decline. We analyzed sarcopenia and sarcopenia dynamics in elderly head-and-neck squamous cell carcinoma (HNSCC) patients undergoing (chemo)radiation. Skeletal muscle mass of 280 elderly HNSCC-patients (>65 yrs) receiving curative (chemo)radiation was manually outlined and quantified on CT scans at the level of the C3 (C3MA). Cross-sectional muscle area at L3 (L3MA) was calculated and normalized to height (L3MI). Frequency distributions of clinical parameters as well as overall survival (OS), progression-free survival (PFS) and locoregional control (LRC) were calculated regarding sarcopenia. Calculated L3MA correlated with pretherapeutic hemoglobin-levels (ρ = 0.280) bodyweight (ρ = 0.702) and inversely with patient-age (ρ = −0.290). Sarcopenic patients featured larger tumors (T3/4 69.0% vs. 52.8%, p < 0.001), a higher burden of comorbidity (age-adjusted Charlson Comorbidity Index 4.8 vs. 4.2, p = 0.015) and more severe chronic toxicities (CTCAE grade 3/4 24.0% vs. 11.8%, p = 0.022). OS was significantly deteriorated in sarcopenic patients with a median of 23 vs. 91 months (logrank p = 0.002) (HR 1.79, CI 1.22−2.60, p = 0.003) and sarcopenia remained an independent prognostic factor for reduced OS in the multivariate analysis (HR 1.64, CI 1.07−2.52, p = 0.023). After therapy, 33% of previously non-sarcopenic patients developed sarcopenia, while 97% of pre-treatment sarcopenic remained sarcopenic. Median bodyweight decreased by 6.8%, whereas median calculated L3MA decreased by 2.4%. In contrast to pretherapeutic, post-therapeutic sarcopenia is no prognosticator for reduced OS. Pretherapeutic sarcopenia is a significant prognostic factor in elderly HNSCC patients undergoing (chemo-)radiation and should be considered in pretherapeutic decision-making. Its role as a predictive marker for tailored supportive interventions merits further prospective evaluation.

Variation in aorta attenuation in contrast-enhanced CT and its implications for calcification thresholds

Background

CT contrast media improves vessel visualization but can also confound calcification measurements. We evaluated variance in aorta attenuation from varied contrast-enhancement scans, and quantified expected plaque detection errors when thresholding for calcification.

Methods

We measured aorta attenuation (AoHU) in central vessel regions from 10K abdominal CT scans and report AoHU relationships to contrast phase (non-contrast, arterial, venous, delayed), demographic variables (age, sex, weight), body location, and scan slice thickness. We also report expected plaque segmentation false-negative errors (plaque pixels misidentified as non-plaque pixels) and false-positive errors (vessel pixels falsely identified as plaque), comparing a uniform thresholding approach and a dynamic approach based on local mean/SD aorta attenuation.

Results

Females had higher AoHU than males in contrast-enhanced scans by 65/22/20 HU for arterial/venous/delayed phases (p < 0.001) but not in non-contrast scans (p > 0.05). Weight was negatively correlated with AoHU by 2.3HU/10kg but other predictors explained only small portions of intra-cohort variance (R² < 0.1 in contrast-enhanced scans). Average AoHU differed by contrast phase, but considerable overlap was seen between distributions. Increasing uniform plaque thresholds from 130HU to 200HU/300HU/400HU produces respective false-negative plaque content losses of 35%/60%/75% from all scans with corresponding false-positive errors in arterial-phase scans of 95%/60%/15%. Dynamic segmentation at 3SD above mean AoHU reduces false-positive errors to 0.13% and false-negative errors to 8%, 25%, and 70% in delayed, venous, and arterial scans, respectively.

Conclusion

CT contrast produces heterogeneous aortic enhancements not readily determined by demographic or scan protocol factors. Uniform CT thresholds for calcified plaques incur high rates of pixel classification errors in contrast-enhanced scans which can be minimized using dynamic thresholds based on local aorta attenuation. Care should be taken to address these errors and sex-based biases in baseline attenuation when designing automatic calcification detection algorithms intended for broad use in contrast-enhanced CTs.

Everything You Always Wanted to Know about Sarcopenia but Were Afraid to Ask: A Quick Guide for Radiation Oncologists (Impact of Sarcopenia in Radiotherapy: The AFRAID Project)

Sarcopenia (SP) is a syndrome characterized by age-associated loss of skeletal muscle mass and function. SP worsens both acute and late radiation-induced toxicity, prognosis, and quality of life. Myosteatosis is a pathological infiltration of muscle tissue by adipose tissue which often precedes SP and has a proven correlation with prognosis in cancer patients. Sarcopenic obesity is considered a "hidden form" of SP (due to large fat mass) and is independently related to higher mortality and worse complications after surgery and systemic treatments with worse prognostic impact compared to SP alone. The evaluation of SP is commonly based on CT images at the level of the middle of the third lumbar vertebra. On this scan, all muscle structures are contoured and then the outlined surface area is calculated. Several studies reported a negative impact of SP on overall survival in patients undergoing RT for tumors of the head and neck, esophagus, rectum, pancreas, cervix, and lung. Furthermore, several appetite-reducing side effects of RT, along with more complex radiation-induced mechanisms, can lead to SP through, but not limited to, reduced nutrition. In particular, in pediatric patients, total body irradiation was associated with the onset of SP and other changes in body composition leading to an increased risk of cardiometabolic morbidity in surviving adults. Finally, some preliminary studies showed the possibility of effectively treating SP and preventing the worsening of SP during RT. Future studies should be able to provide information on how to prevent and manage SP before, during, or after RT, in both adult and pediatric patients.

Prognostic Value of [18F]-FDG PET/CT Radiomics Combined with Sarcopenia Status among Patients with Advanced Gastroesophageal Cancer

We investigated, whether 18[18F]-FDG PET/CT-derived radiomics combined with sarcopenia measurements improves survival prognostication among patients with advanced, metastatic gastroesophageal cancer. In our study, 128 consecutive patients with advanced, metastatic esophageal and gastroesophageal cancer (n = 128; 26 females; 102 males; mean age 63.5 ± 11.7 years; age range: 29−91 years) undergoing 18[18F]-FDG PET/CT for staging between November 2008 and December 2019 were included. Segmentation of the primary tumor and radiomics analysis derived from PET and CT images was performed semi-automatically with a commonly used open-source software platform (LIFEX, Version 6.30, lifexsoft.org). Patients’ nutritional status was determined by measuring the skeletal muscle index (SMI) at the level of L3 on the CT component. Univariable and multivariable analyses were performed to establish a survival prediction model including radiomics, clinical data, and SMI score. Univariable Cox proportional hazards model revealed ECOG (<0.001) and bone metastasis (p = 0.028) to be significant clinical parameters for overall survival (OS) and progression free survival (PFS). Age (p = 0.017) was an additional prognostic factor for OS. Multivariable analysis showed improved prognostication for overall and progression free survival when adding sarcopenic status, PET and CT radiomics to the model with clinical parameters only. PET and CT radiomics derived from hybrid 18[18F]-FDG PET/CT combined with sarcopenia measurements and clinical parameters may improve survival prediction among patients with advanced, metastatic gastroesophageal cancer.

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

RATIONALE AND OBJECTIVES

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).

MATERIALS AND METHODS

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.

RESULTS

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.

CONCLUSION

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.

Current Approach to the Diagnosis of Sarcopenia in Heart Failure: A Narrative Review on the Role of Clinical and Imaging Assessments

Sarcopenia has been established as a predictor of poor outcomes in various clinical settings. It is particularly prevalent in heart failure, a clinical syndrome that poses significant challenges to health care worldwide. Despite this, sarcopenia remains overlooked and undertreated in cardiology practice. Understanding the currently proposed diagnostic process is paramount for the early detection and treatment of sarcopenia to mitigate downstream adverse health outcomes.

CT-Derived Body Composition Assessment as a Prognostic Tool in Oncologic Patients: From Opportunistic Research to Artificial Intelligence-Based Clinical Implementation

CT-based body composition measures are well established in research settings as prognostic markers in oncologic patients. Numerous retrospective studies have shown the role of objective measurements extracted from abdominal CT images of skeletal muscle, abdominal fat, and bone mineral density in providing more accurate assessments of frailty and cancer cachexia in comparison with traditional clinical methods. Quantitative CT-based measurements of liver fat and aortic atherosclerotic calcification have received relatively less attention in cancer care but also provide prognostic information. Patients with cancer routinely undergo serial CT examinations for staging, treatment response, and surveillance, providing the opportunity for quantitative body composition assessment to be performed as part of routine clinical care. The emergence of fully automated artificial intelligence-based segmentation and quantification tools to replace earlier time-consuming manual and semiautomated methods for body composition analysis will allow these opportunistic measures to transition from the research realm to clinical practice. With continued investigation, the measurements may ultimately be applied to achieve more precise risk stratification as a component of personalized oncologic care.

Effect of Pre-Existent Sarcopenia on Oncological Outcome of Advanced Thyroid Cancer Patients Treated with Tyrosine Kinase Inhibitors

(1) Background: Sarcopenia is associated with poor survival and treatment outcomes in several human cancers. The aim of the study was to investigate the prevalence of sarcopenia in a cohort of 58 Caucasian patients with advanced thyroid cancer before and during TKI treatment. The impact of this condition on the outcome of patients was also evaluated. (2) Methods: Sarcopenia was evaluated using the Skeletal Muscle Index (SMI). (3) Results: Pre-treatment sarcopenia was found in 20.7% of patients and this condition significantly affected treatment outcome, emerging as the parameter that has the greatest impact on Progression Free Survival (PFS) (HR 4.29; 95% CI, 1.21−15.11, p = 0.02). A significant reduction in SMI values was observed 3 (p = 0.002) and 12 months (p < 0.0001) after TKI treatment. At a 12-month follow-up, sarcopenia prevalence increased up to 38.5%. Here, 12-month sarcopenia was predicted by a lower SMI (p = 0.029), BMI (p = 0.02) and weight (p = 0.04) and by the presence of bone metastases (p = 0.02). (4) Conclusions: This is the first study that evaluated sarcopenia prevalence and its change over time in Caucasian patients with advanced thyroid cancer under TKI therapy. Sarcopenia seems to be a prognostic factor of TKI treatment outcome, suggesting the importance of the assessment of the nutritional status and body composition in advanced thyroid cancer patients.

Low skeletal muscle radiodensity and neutrophil-to-lymphocyte ratio as predictors of poor outcome in patients with COVID-19

Inflammatory states and body composition changes are associated with a poor prognosis in many diseases, but their role in coronavirus disease 2019 (COVID-19) is not fully understood. To assess the impact of low skeletal muscle radiodensity (SMD), high neutrophil-to-lymphocyte ratio (NLR) and a composite score based on both variables, on complications, use of ventilatory support, and survival in patients with COVID-19. Medical records of patients hospitalized between May 1, 2020, and July 31, 2020, with a laboratory diagnosis of COVID-19 who underwent computed tomography (CT) were retrospectively reviewed. CT-derived body composition measurements assessed at the first lumbar vertebra level, and laboratory tests performed at diagnosis, were used to calculate SMD and NLR. Prognostic values were estimated via univariate and multivariate logistic regression analyses and the Kaplan-Meier curve. The study was approved by the local Institutional Review Board (CAAE 36276620.2.0000.5404). A total of 200 patients were included. Among the patients assessed, median age was 59 years, 58% were men and 45% required ICU care. A total of 45 (22.5%) patients died. Multivariate logistic analysis demonstrated that a low SMD (OR 2.94; 95% CI 1.13-7.66, P = 0.027), high NLR (OR 3.96; 95% CI 1.24-12.69, P = 0.021) and both low SMD and high NLR (OR 25.58; 95% CI 2.37-276.71, P = 0.008) combined, were associated with an increased risk of death. Patients who had both low SMD and high NLR required more mechanical ventilation (P < 0.001) and were hospitalized for a longer period (P < 0.001). Low SMD, high NLR and the composite score can predict poor prognosis in patients with COVID-19, and can be used as a tool for early identification of patients at risk. Systemic inflammation and low muscle radiodensity are useful predictors of poor prognosis, and the assessment of these factors in clinical practice should be considered.

A new finding for the obesity paradox? Evaluation of the relationship between muscle and adipose tissue in nuclear grade prediction in patients with clear cell renal cell carcinoma

Background

Obesity is associated with an increased risk of developing clear cell renal cell carcinoma (ccRCC), but paradoxically there is a positive association between obesity and surveillance.

Purpose

To investigate the relationship between nucleus grade classification and body composition in patients with matched co-morbid conditions with non-metastatic ccRCC.

Materials and Methods

A total of 253 patients with non-metastatic ccRCC were included in the study. Body composition was assessed with abdominal computed tomography (CT) using an automated artificial intelligence software. Both adipose and muscle tissue parameters of the patients were calculated. In order to investigate the net effect of body composition, propensity score matching (PSM) procedure was applied over age, sex, and T stage parameters. In this way, selection bias and imbalance between groups were minimized. Univariate and multivariate logistic regression analyses were performed to identify the association between body composition and WHO/ISUP grade (I–IV).

Result

When the body composition of the patients was examined without matching the conditions, it was found that the subcutaneous adipose tissue (SAT) values were higher in patients with low grades ( P = 0.001). Normal attenuation muscle area (NAMA) was higher in high-grade patients than low-grade patients ( P < 0.05). In the post-matching evaluation, only SAT/NAMA was found to be associated with high-grade ccRCC (univariate analysis: odds ratio [OR]=0.899, 95% confidence interval [CI]=0.817−0.988, P = 0.028; multivariate analysis: OR=0.922, 95% CI=0.901−0.974, P = 0.042).

Conclusion

CT-based body composition parameters can be used as a prognostic marker in predicting nuclear grade when age, sex, and T stage match conditions. This finding offers a new perspective on the obesity paradox.

Prognostic significance of postoperative loss of skeletal muscle mass in patients underwent coronary artery bypass grafting

Background

Increasing life expectancy of coronary artery bypass grafting (CABG) remains to be the major concern of cardiac surgeons. However, few studies have investigated the effect of postoperative skeletal muscle index (SMI) loss on prognosis. This study aims to evaluate the prognostic role of postoperative SMI loss ≥ 5% after CABG, in order to develop a novel nomogram to predict overall survival (OS).

Methods

Patients underwent CABG via midline sternotomy from December 2015 to March 2021 were recruited in this study. Preoperative and postoperative 3 months chest computed tomography (CT) images were compared to assess changes in SMI at T12 level. Based on this, patients were classified into the presence or absence of SMI loss ≥ 5%. The association between postoperative SMI loss ≥ 5% and OS was then analyzed by the Kaplan-Meier curves and Cox model. A novel nomogram incorporating independent clinical prognostic variables was also developed.

Results

The study enrolled 506 patients receiving CABG, of whom 98 patients experienced T12 SMI loss ≥ 5% and had a significantly worse OS (P < 0.0001). Multivariate regression analysis showed that T12 SMI per cent change (%T12 SMI-change) was an independent prognostic factor for OS (HR = 0.809, 95% CI = 0.749–0.874). The nomogram incorporating %T12 SMI-change with other variables was accurate for predicting OS. Besides, we also found that postoperative oral nutritional supplement (ONS) can rescue T12 SMI loss.

Conclusion

Postoperative SMI loss can predict survival outcome after CABG. The nomogram incorporating changes in SMI provides a superior performance than existing systems.

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.

Prognostic Effect of Thoracic Sarcopaenia on Short- and Long-Term Clinical Outcomes in Patients Underwent Cardiac Valve Surgery

BACKGROUND

As the proportion of elderly patients increases, higher incidence of malnutrition is found among patients with valvular heart disease. Sarcopaenia is one of the main manifestations of malnutrition. Studies have shown the certain predictive effect of sarcopaenia on the clinical outcome in different cases. This study aims to clarify the impact of computed tomography (CT)-derived thoracic sarcopaenia on clinical outcomes of patients underwent cardiac valve surgery.

METHODS

The clinical data of 216 patients who underwent cardiac valve surgery from December 2015 to June 2020 were retrospectively collected. Skeletal muscle mass at 12^th thoracic vertebra level was measured to diagnose thoracic sarcopaenia. Postoperative complications and follow-up data were collected. Medium follow-up was 3.2 years.

RESULTS

The prevalence of thoracic sarcopaenia was 16.7% in this study. The incidence of total complications and in-hospital mortality were higher in thoracic sarcopaenia group (p=0.024 and p=0.014, respectively). Multivariate analysis revealed that thoracic sarcopaenia is a significant predictor for postoperative complications (OR 2.319; 95% CI 1.003-5.366; p=0.049). Decreased long-term survival was observed in patients with thoracic sarcopaenia. Thoracic sarcopaenia (HR 4.178; 95% CI 2.062-8.465; p<0.001) was determined to be an independent risk factor for late mortality.

CONCLUSION

Thoracic sarcopaenia defined by chest CT was independently associated with higher incidence of postoperative complications and long-term mortality. Routine preoperative evaluation of thoracic sarcopaenia deserves further consideration to enhance the predictive performance for operation risk.

The impact of sarcopenia on short-term and long-term mortality in patients with septic shock

BACKGROUND

Despite medical advances, septic shock remains one of the main causes of high mortality in critically ill patients. Although sarcopenia is considered a predictor of mortality in septic shock patients, most studies have only investigated short-term mortality, and those on long-term prognosis are limited. We investigated the impact of sarcopenia on long-term mortality in a large patient population with septic shock.

METHODS

A retrospective cohort study comprising 905 patients with septic shock was conducted from 2008 to 2019. Sarcopenia was defined based on the measurement of the total abdominal muscle area, assessed using abdominal computed tomography scans. Thereafter, we stratified the patients into two groups-sarcopenia and non-sarcopenia groups-and compared the impact of sarcopenia on short-term (28 days) and long-term (1 year and overall) mortality using multivariable Cox proportional analysis.

RESULTS

A total of 905 patients were included, and the mean age was 65.7 ± 15.1 years. Among them, 430 (47.5%) patients were male and 407 (45.0%) had sarcopenia. We found that the 28 day, 1 year, and overall mortality rates in the sarcopenia group were significantly higher than those in the non-sarcopenia group (13.8% vs. 6.4%, P < 0.001; 41.8% vs. 21.7%, P < 0.001; 62.2% vs. 35.7%, P < 0.001, respectively). Univariable Cox analysis showed that the sarcopenia group had a significant association with the increase in each mortalities compared with the non-sarcopenia group (28 day mortality, hazard ratio (HR) = 2.230, 95% confidence interval (CI) [1.444-3.442], P < 0.001; 1 year mortality, HR = 2.189, 95% CI [1.720, 2.787], P < 0.001; overall mortality, HR = 2.254, 95% CI [1.859, 2.734], P < 0.001). Multivariable Cox analysis showed that both the short-term and long-term mortality rates remained significantly higher in the sarcopenia group than in the non-sarcopenia group, even after adjusting for confounding variables (28 day mortality, HR = 2.116, 95% CI [1.312, 3.412], P = 0.002; 1 year mortality, HR = 1.679, 95% CI [1.291, 2.182], P < 0.001; overall mortality, HR = 1.704, 95% CI [1.381, 2.102], P < 0.001).

CONCLUSIONS

Sarcopenia was associated with both short-term and long-term mortality in patients with septic shock. In clinical settings, close attention should be paid to these patients for both short-term and long-term outcomes.

Guidance for assessment of the muscle mass phenotypic criterion for the Global Leadership Initiative on Malnutrition diagnosis of malnutrition

The Global Leadership Initiative on Malnutrition (GLIM) provides consensus criteria for the diagnosis of malnutrition that can be widely applied. The GLIM approach is based on the assessment of three phenotypic (weight loss, low body mass index, and low skeletal muscle mass) and two etiologic (low food intake and presence of disease with systemic inflammation) criteria, with diagnosis confirmed by any combination of one phenotypic and one etiologic criterion fulfilled. Assessment of muscle mass is less commonly performed than other phenotypic malnutrition criteria, and its interpretation may be less straightforward, particularly in settings that lack access to skilled clinical nutrition practitioners and/or to body composition methodologies. In order to promote the widespread assessment of skeletal muscle mass as an integral part of the GLIM diagnosis of malnutrition, the GLIM consortium appointed a working group to provide consensus-based guidance on assessment of skeletal muscle mass. When such methods and skills are available, quantitative assessment of muscle mass should be measured or estimated using dual-energy x-ray absorptiometry, computerized tomography, or bioelectrical impedance analysis. For settings where these resources are not available, then the use of anthropometric measures and physical examination are also endorsed. Validated ethnic- and sex-specific cutoff values for each measurement and tool are recommended when available. Measurement of skeletal muscle function is not advised as surrogate measurement of muscle mass. However, once malnutrition is diagnosed, skeletal muscle function should be investigated as a relevant component of sarcopenia and for complete nutrition assessment of persons with malnutrition.

Combined 18 F-FDG PET/CT Radiomics and Sarcopenia Score in Predicting Relapse-Free Survival and Overall Survival in Patients With Esophagogastric Cancer

PURPOSE

The aim of this study was to determine if radiomic features combined with sarcopenia measurements on pretreatment 18 F-FDG PET/CT can improve outcome prediction in surgically treated adenocarcinoma esophagogastric cancer patients.

PATIENTS AND METHODS

One hundred forty-five esophageal adenocarcinoma patients with curative therapeutic intent and available pretreatment 18 F-FDG PET/CT were included. Textural features from PET and CT images were evaluated using LIFEx software ( lifexsoft.org ). Sarcopenia measurements were done by measuring the Skeletal Muscle Index at L3 level on the CT component. Univariable and multivariable analyses were conducted to create a model including the radiomic parameters, clinical features, and Skeletal Muscle Index score to predict patients' outcome.

RESULTS

In multivariable analysis, we combined clinicopathological parameters including ECOG, surgical T, and N staging along with imaging derived sarcopenia measurements and radiomic features to build a predictor model for relapse-free survival and overall survival. Overall, adding sarcopenic status to the model with clinical features only (likelihood ratio test P = 0.03) and CT feature ( P = 0.0037) improved the model fit for overall survival. Similarly, adding sarcopenic status ( P = 0.051), CT feature ( P = 0.042), and PET feature ( P = 0.011) improved the model fit for relapse-free survival.

CONCLUSIONS

PET and CT radiomics derived from combined PET/CT integrated with clinicopathological parameters and sarcopenia measurement might improve outcome prediction in patients with nonmetastatic esophagogastric adenocarcinoma.

Prevalence of Sarcopenia in Patients With COVID-19: A Systematic Review and Meta-Analysis

BACKGROUND

It has been speculated that patients with sarcopenia are aggravated by the current novel coronavirus disease 2019 (COVID-19) epidemic. However, there is substantial uncertainty regarding the prevalence of sarcopenia in patients with COVID-19.

OBJECTIVES

The purpose of the study was to systematically evaluate the prevalence of sarcopenia in patients with COVID-19, including stratification by gender, study location, study population, study design, and diagnostic criteria.

DESIGN

This is the systematic literature review and meta-analysis.

METHODS

An electronic search was performed in MEDLINE/PubMed, Embase, Cochrane Library, and Web of Science and Scopus to identify observational studies reporting a prevalence estimate for sarcopenia in patients with COVID-19. Studies were reviewed in accordance with the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines and a meta-analysis was performed. Risk of bias (RoB) was assessed using the Newcastle-Ottawa Scale (NOS) for cohort studies and Joanna Briggs Institute (JBI) manual for cross-sectional studies, and Stata 14.0 was used to perform meta-analyses.

RESULTS

A total of 4,639 studies were initially identified. After removing the duplicates and applying the selection criteria, we reviewed 151 full-text studies. A total of 21 studies, including 5,407 patients, were eligible for inclusion in this review finally. The prevalence of sarcopenia in patients with COVID-19 in individual studies varied from 0.8 to 90.2%. The pooled prevalence of sarcopenia in COVID-19 was 48.0% (95% confidence interval, CI: 30.8 to 65.1%, I 2 = 99.68%, p = 0.000). We did not find any significant differences in the prevalence estimates between gender specificity (OR = 1.34; 95% CI = 0.80-2.26; p = 0.001). By sex, the prevalence was 42.5% (95% CI: 31.7 to 53.4%) in men and 35.7% (95% CI: 24.2 to 47.2%) in women. The prevalence estimates significantly varied based on population settings and different diagnostic criteria of sarcopenia. ICU patients (69.7, 95% CI: 51.7 to 85.2%) were more likely to suffer from sarcopenia compared to other population settings.

CONCLUSION

To our knowledge, this is the first meta-analysis reporting on the prevalence of sarcopenia in patients with COVID-19. Sarcopenia is frequently observed in patients with COVID-19, with varying prevalence across population settings. This study would be useful for clinicians to prompt the increasing awareness of identifying sarcopenia and developing interventions at patients with COVID-19 with high risk of sarcopenia. Further prospective longitudinal studies to define the association of sarcopenia and its prognostic outcomes in COVID-19 survivors are urgently needed to propose the most appropriate treatment strategies during their admission and discharge.

SYSTEMATIC REVIEW REGISTRATION

[www.crd.york.ac.uk/prospero/], identifier [CRD42022300431].

The psoas muscle depletion index is related to the degree of cirrhosis and skeletal muscle loss in patients with end-stage liver disease

OBJECTIVE

To establish a new psoas muscle depletion index (PDI) from healthy young donors and to explore the correlation between the PDI and the severity of cirrhosis in patients with endstage liver disease (ESLD).

METHODS

Clinical data of 461 healthy donors were collected during the period 2014-2019, and clinical data of 331 patients with ESLD were collected during the period 2014-2018. The patients were divided into four groups by PDI severity: PDI ≥ 0.90, PDI = 0.75-0.90, PDI = 0.50-0.75 and PDI ≤ 0.50 (Gsev). Differences in international normalised ratio (INR), total bilirubin and serum creatinine levels, and Child-Pugh (CP) and model for end-stage liver disease (MELD) scores were compared. The sarcopenia incidence according to the PDI and the psoas muscle index (PMI) in different weight groups were also compared.

RESULTS

Gsev had the highest CP (10.2 ± 2.1) and MELD (20.1 ± 7.4) scores and total bilirubin (166.3 ± 192.0 umol/L) and blood creatinine (92.9 ± 90.2 umol/L) levels and the lowest haemoglobin (93.8 ± 21.7 g/L) and blood albumin (30.9 ± 5.8 g/L) levels. Gsev showed significant changes in INR (1.74 ± 0.65) and blood sodium (135.3 ± 5.65 mmol/L). If PDI <0.75 was used as the diagnostic criterion for sarcopenia, the incidence was 53.3% in patients weighing >90 kg and 53.6% in those weighing <60 kg. This differed from the PMI, with an incidence of 3.3% in patients weighing >90 kg.

CONCLUSIONS

The PDI had no significant correlation with body height, body weight or body mass index (BMI) in healthy individuals and patients with ESLD. The PDI was significantly correlated with the severity of cirrhosis and loss of skeletal muscle.

MRI biomarker of muscle composition is associated with severity of pelvic organ prolapse

BACKGROUND

The pathophysiology of pelvic organ prolapse is largely unknown. We hypothesized that reduced muscle mass on magnetic resonance defecography (MRD) is associated with increased pelvic floor laxity. The aim of this study was to compare the psoas and puborectalis muscle mass composition and cross-sectional area among patients with or without pelvic laxity.

METHODS

An observational retrospective study was conducted on women > age 18 years old who had undergone MRD for pelvic floor complaints from January 2020 to December 2020 at Stanford Pelvic Health Center. Pelvic floor laxity, pelvic organ descent, and rectal prolapse were characterized by standard measurements on MRD and compared to the psoas (L4 level) and puborectalis muscle index (cross-sectional area adjusted by height) and relative fat fraction, quantified by utilizing a 2-point Dixon technique. Regression analysis was used to quantify the association between muscle characteristics and pelvic organ measurements.

RESULTS

The psoas fat fraction was significantly elevated in patients with abnormally increased resting and strain H and M lines (p < 0.05) and increased with rising grades of Oxford rectal prolapse (p = 0.0001), uterovaginal descent (p = 0.001) and bladder descent (p = 0.0005). In multivariate regression analysis, adjusted for age and body mass index, the psoas fat fraction (not muscle index) was an independent risk factor for abnormal strain H and M line; odds ratio (95% confidence interval) of 17.8 (2-155.4) and 18.5 (1.3-258.3) respectively, and rising Oxford grade of rectal prolapse 153.9 (4.4-5383) and bladder descent 12.4 (1.5-106). Puborectalis fat fraction was increased by rising grades of Oxford rectal prolapse (p = 0.0002).

CONCLUSIONS

Severity of pelvic organ prolapse appears to be associated with increasing psoas muscle fat fraction, a biomarker for reduced skeletal muscle mass. Future prospective research is needed to determine if sarcopenia may predict postsurgical outcomes after pelvic organ prolapse repair.

Development and Validation of Global Leadership Initiative on Malnutrition for Prognostic Prediction in Patients Who Underwent Cardiac Surgery

The Global Leadership Initiative on Malnutrition (GLIM) has achieved a consensus for the diagnosis of malnutrition in recent years. This study aims to determine the prognostic effect of the GLIM after cardiac surgery. A total of 603 patients in the training cohort and 258 patients in the validation cohort were enrolled in this study. Perioperative characteristics and follow-up data were collected. A nomogram based on independent prognostic predictors was developed for survival prediction. In total, 114 (18.9%) and 48 (18.6%) patients were defined as being malnourished according to the GLIM criteria in the two cohorts, respectively. Multivariate regression analysis showed that GLIM-defined malnutrition was an independent risk factor of total complication (OR 1.661, 95% CI: 1.063–2.594) and overall survival (HR 2.339, 95% CI: 1.504–3.637). The c-index was 0.72 (95% CI: 0.66–0.79) and AUC were 0.800, 0.798, and 0.780 for 1-, 2-, and 3-year survival prediction, respectively. The calibration curves of the nomogram fit well. In conclusion, GLIM criteria can efficiently identify malnutrition and has a prognostic effect on clinical outcomes after cardiac surgery. GLIM-based nomogram has favorable performance in survival prediction.

Muscle fat infiltration but not muscle cross-sectional area is independently associated with bone mineral density at the lumbar spine

OBJECTIVE

Although sarcopenia and osteoporosis are inter-related conditions that are common with advancing age, few studies have explored relationships between muscle quality and bone mineral density (BMD). We investigated age- and sex-specific paraspinal muscle fat infiltration (MFI), muscle cross-sectional area (CSA), and spine volumetric BMD (vBMD) in healthy Chinese adults.

METHODS

605 healthy adults aged 20-59 years (340 women, mean age 39.2 years; 265 men, mean age 38.8 years) had axial T2WI MRI imaging of the lumbar spine and CSA (cm2) and MFI (%) were measured in the psoas and multifidus and erector spinae (MF-ES) muscles (L3-L4). MFI measurements were calibrated against a region of interest in an adjacent area of subcutaneous pure fat. L2-L4 vBMD was measured by quantitative CT. Age- and sex-specific subgroups were compared using the Mann-Whitney test. Multiple regression was used to test independent associations of MFI and CSA with vBMD.

RESULTS

Females had lower CSA and higher MFI than males in both the psoas and MF-ES muscles (p < 0.001). In females and males, MF-ES MFI increased with age (p < 0.001) and in females age-related increases were observed for the psoas muscles (p < 0.05). Greater fat infiltration of the MS-ES muscle unit was associated with lower vBMD in both sexes (p < 0.001) but not with CSA. Following adjustment for demographic variables and CSA, MS-ES MFI remained predictive of vBMD (β = -0.408 to -0.157, p < 0.001).

CONCLUSION

We have demonstrated that, independent of CSA and demographic variables, MFI of the MF-ES muscles is predictive of lower lumbar spine vBMD in both sexes.

ADVANCES IN KNOWLEDGE

This is the first study to demonstrate that, independent of muscle size and demographic variables, MFI of the paraspinal MF-ES muscles is predictive of lower lumbar spine vBMD in both sexes.

Diagnosis and Pathogenesis of Sarcopenia in Chronic Liver Disease Using Liver Magnetic Resonance Imaging

Background Liver magnetic resonance imaging (MRI) is rarely used to evaluate sarcopenia. This study sought to develop new diagnostic criteria for MRI in Asians and investigate the relationship between adipopenia and sarcopenia using MRI proton density fat fraction (PDFF), which is correlated with body fat mass. Methodology This study included 512 patients with chronic liver disease (CLD) who underwent magnetic resonance elastography (MRE). The following parameters were assessed: paraspinal muscle area/height index (PSMI) measured at the level of the superior mesenteric artery and PDFF. The cutoff PSMI and PDFF values for the diagnosis of sarcopenia and adipopenia, respectively, were determined using receiver operating characteristic analysis of Asians with low body mass index. Results Among patients with CLD, the prevalence rates of sarcopenia and adipopenia were 25% and 17%, respectively. We found that sarcopenia increased from stage 3 fibrosis and was inversely correlated with steatosis grade. Multivariate analysis found that MRI-PDFF was associated with sarcopenia. The Kaplan-Meier method in cirrhosis (n = 122) showed that the non-sarcopenia, sarcopenia, and sarcopenia/adipopenia groups had three-year survival rates of 97%, 55% (p < 0.01), and 23%, respectively. The Cox proportional hazards model identified the Child-Pugh score and sarcopenia/adipopenia as independent prognostic factors. Conclusions The new diagnostic criteria for sarcopenia confirmed that the prognosis of cirrhosis can be stratified. Furthermore, sarcopenia with adipopenia was shown to be a phenotype of severe sarcopenia in cirrhosis, and screening for sarcopenia should include cases in the precirrhotic stage.

Determination of Low Muscle Mass by Muscle Surface Index of the First Lumbar Vertebra Using Low-Dose Computed Tomography

The muscle index of the first vertebra (L1MI) derived from computed tomography (CT) is an indicator of total skeletal muscle mass. Nevertheless, the cutoff value and utility of L1MI derived from low-dose chest CT (LDCT) remain unclear. Adults who received LDCT for health check-ups in 2017 were enrolled. The cutoff values of L1MI were established in subjects aged 20-60 years. The cutoff values were used in chronic obstructive pulmonary disease (COPD) patients to determine muscle quantity. A total of 1780 healthy subjects were enrolled. Subjects (n = 1393) aged 20-60 years were defined as the reference group. The sex-specific cutoff values of L1MI were 26.2 cm²/m² for males and 20.9 cm²/m² for females. Six subjects in the COPD group (6/44, 13.6%) had low L1MI. COPD subjects with low L1MI had lower forced expiratory volume in one second (0.81 ± 0.17 vs. 1.30 ± 0.55 L/s, p = 0.046) and higher COPD assessment test scores (19.5 ± 2.6 vs. 15.0 ± 4.9, p = 0.015) than those with normal L1MI. In conclusion, LDCT in health assessments may provide additional information on sarcopenia.

Prediction of abdominal CT body composition parameters by thoracic measurements as a new approach to detect sarcopenia in a COVID-19 cohort

As most COVID-19 patients only receive thoracic CT scans, but body composition, which is relevant to detect sarcopenia, is determined in abdominal scans, this study aimed to investigate the relationship between thoracic and abdominal CT body composition parameters in a cohort of COVID-19 patients. This retrospective study included n = 46 SARS-CoV-2-positive patients who received CT scans of the thorax and abdomen due to severe disease progression. The subcutaneous fat area (SF), the skeletal muscle area (SMA), and the muscle radiodensity attenuation (MRA) were measured at the level of the twelfth thoracic (T12) and the third lumbar (L3) vertebra. Necessity of invasive mechanical ventilation (IMV), length of stay, or time to death (TTD) were noted. For statistics correlation, multivariable linear, logistic, and Cox regression analyses were employed. Correlation was excellent for the SF (r = 0.96) between T12 and L3, and good for the respective SMA (r = 0.80) and MRA (r = 0.82) values. With adjustment (adj.) for sex, age, and body-mass-index the variability of SF (adj. r² = 0.93; adj. mean difference = 1.24 [95% confidence interval (95% CI) 1.02–1.45]), of the SMA (adj. r² = 0.76; 2.59 [95% CI 1.92–3.26]), and of the MRA (adj. r² = 0.67; 0.67 [95% CI 0.45–0.88]) at L3 was well explained by the respective values at T12. There was no relevant influence of the SF, MRA, or SMA on the clinical outcome. If only thoracic CT scans are available, CT body composition values at T12 can be used to predict abdominal fat and muscle parameters, by which sarcopenia and obesity can be assessed.

Guidance for assessment of the muscle mass phenotypic criterion for the Global Leadership Initiative on Malnutrition (GLIM) diagnosis of malnutrition

The Global Leadership Initiative on Malnutrition (GLIM) provides consensus criteria for the diagnosis of malnutrition that can be widely applied. The GLIM approach is based on the assessment of three phenotypic (weight loss, low body mass index, and low skeletal muscle mass) and two etiologic (low food intake and presence of disease with systemic inflammation) criteria, with diagnosis confirmed by any combination of one phenotypic and one etiologic criterion fulfilled. Assessment of muscle mass is less commonly performed than other phenotypic malnutrition criteria, and its interpretation may be less straightforward, particularly in settings that lack access to skilled clinical nutrition practitioners and/or to body composition methodologies. In order to promote the widespread assessment of skeletal muscle mass as an integral part of the GLIM diagnosis of malnutrition, the GLIM consortium appointed a working group to provide consensus-based guidance on assessment of skeletal muscle mass. When such methods and skills are available, quantitative assessment of muscle mass should be measured or estimated using dual-energy x-ray absorptiometry, computerized tomography, or bioelectrical impedance analysis. For settings where these resources are not available, then the use of anthropometric measures and physical examination are also endorsed. Validated ethnic- and sex-specific cutoff values for each measurement and tool are recommended when available. Measurement of skeletal muscle function is not advised as surrogate measurement of muscle mass. However, once malnutrition is diagnosed, skeletal muscle function should be investigated as a relevant component of sarcopenia and for complete nutrition assessment of persons with malnutrition.

Utility of Noncancerous Chest CT Features for Predicting Overall Survival and Noncancer Death in Patients With Stage I Lung Cancer Treated With Stereotactic Body Radiotherapy

Background: Noncancerous imaging markers can be readily derived from pretreatment diagnostic and radiotherapy planning chest CT examinations. Objective: To explore the ability of noncancerous features on chest CT to predict overall survival (OS) and noncancer-related death in patients with stage I lung cancer treated with stereotactic body radiation therapy (SBRT). Methods: This retrospective study included 282 patients (168 female, 114 male; median age, 75 years) with stage I lung cancer treated with SBRT between January 2009 and June 2017. Pretreatment chest CT was used to quantify coronary artery calcium (CAC) score, pulmonary artery (PA)-to-aorta ratio, emphysema, and body composition in terms of the cross-sectional area and attenuation of skeletal muscle and subcutaneous adipose tissue at the T5, T8, and T10 vertebral levels. Associations of clinical and imaging features with OS were quantified using a multivariable Cox proportional hazards (PH) model. Penalized multivariable Cox PH models to predict OS were constructed using clinical features only and using both clinical and imaging features. Models' discriminatory ability was assessed by constructing time-varying ROC curves and computing AUC at prespecified times. Results: After a median OS of 60.8 months (95% CI 55.8-68.9), 148 (52.5%) patients died, including 83 (56.1%) with noncancer deaths. Higher CAC score (11-399: hazard ratio [HR] 1.83 [95% CI 1.15-2.91], P=.01; ≥400: HR 1.63 [95% CI 1.01-2.63], P=.04), higher PA-to-aorta ratio (HR 1.33 [95% CI 1.16-1.52], P<.001, per 0.1-unit increase), and lower thoracic skeletal muscle index (HR 0.88 [95% CI 0.79-0.98], P=.02, per 10 cm²/m² increase) were independently associated with shorter OS. Discriminatory ability for 5-year OS was greater for the model including clinical and imaging features than for the model including clinical features only (AUC, 0.75 [95% CI 0.68-0.83] versus 0.61 [95% CI 0.53-0.70], p < .01). The model's most important clinical or imaging feature based on mean standardized regression coefficients was the PA-to-aorta ratio. Conclusions: In patients undergoing SBRT for stage I lung cancer, higher CAC score, higher PA-to-aorta ratio, and lower thoracic skeletal muscle index independently predicted worse OS. Clinical Impact: Noncancerous imaging features on chest CT performed before SBRT improve survival prediction compared with clinical features alone.

Impact of Skeletal Muscle Measurements by Chest Computed Tomography on Survival and Postoperative Complications in Patients with Soft Tissue Sarcoma

This study aims to evaluate whether sarcopenia, measured by chest computed tomography (CT), affects survival outcomes and postoperative complications in soft tissue sarcoma (STS) patients undergoing surgery. In this retrospective study, CT scans of 79 patients were reviewed to measure pectoralis and T12 vertebra muscle area. Both were then adjusted for height (cm²/m²) as pectoralis muscle index (PMI) and T12 vertebra muscle index (TMI). Analyses were performed by dichotomizing muscle indices at gender-specific 50th percentile; PMI and TMI < 50th percentile were defined as low, and ≥50th percentile as high. Overall postsurgical complication rate (PCR) was 16%. Median length of hospital stay (LOHS) was 10 days (3-90). PMI and TMI were significantly lower in women (p = 0.02, p = 0.04). Median body mass index was significantly higher in high PMI and TMI groups (p = 0.01 for both). PCR and LOHS were similar between low and high PMI and TMI groups. Median follow-up was 29 months, 37 patients had recurrence and 23 died. No significant difference was noted between low and high PMI and TMI groups, in terms of disease-free or overall survival. PMI and TMI as measured by chest CT had no impact on survival outcomes or postoperative complications in localized STS.

Lower skeletal muscle mass on CT body composition analysis is associated with adverse clinical course and outcome in children with COVID-19

OBJECTIVES

To assess the association between body composition measures in children with COVID-19 and severity of the disease course and clinical outcome.

METHODS

A retrospective study of children (< 19 years) with COVID-19 admitted to the hospital who underwent CT of the chest and/or abdomen was conducted. Data compiled from electronic medical records included demographics, body mass index (BMI), length of stay, ICU admission, invasive mechanical ventilation and death. Waist circumference and perimeters for skeletal muscle mass (abdominal, psoas and paraspinal muscles) were measured on an axial CT image at the level of the twelfth thoracic vertebra or first lumbar vertebra using FIJI software.

RESULTS

Fifty-seven subjects were identified (54% male, median age 15.6 years, 61% Hispanic, 23% African-American). 25% (14/57) were admitted to the ICU and 21% (12/57) needed intubation. 9% (5/57) died. Waist circumference ranged between 53.2 and 138.4 cm (mean 86.58 ± 18.74 cm) and skeletal muscle mass ranged between 0.6 and 6.8 cm2 (mean 3.5 ± 1.19 cm2). Lower skeletal muscle mass had a univariate association with ICU admission (odds ratio (OR) 0.4; 95%CI 0.17-0.76; p = 0.01) and mortality (OR 0.22; 95%CI 0.04-0.69; p = 0.01). Multivariate analysis showed similar association after controlling for comorbidities (adjusted OR 0.46; 95%CI 0.19-0.95; p = 0.04 and adjusted OR 0.31; 95%CI 0.06-0.95; p = 0.04, respectively). There was no association between BMI or waist circumference with ICU stay, mechanical ventilation or mortality.

CONCLUSION

Lower skeletal muscle mass is associated with an adverse clinical course and outcome in children with COVID-19.

Computed tomography on lung cancer screening is useful for adjuvant comorbidity diagnosis in developing countries

Purpose

The aim of this study was to analyse and quantify the prevalence of six comorbidities from lung cancer screening (LCS) on computed tomography (CT) scans of patients from developing countries.

Methods

For this retrospective study, low-dose CT scans (n=775) were examined from patients who underwent LCS in a tertiary hospital between 2016 and 2020. An age- and sex-matched control group was obtained for comparison (n=370). Using the software, coronary artery calcification (CAC), the skeletal muscle area, interstitial lung abnormalities, emphysema, osteoporosis and hepatic steatosis were accessed. Clinical characteristics of each participant were identified. A t-test and Chi-squared test were used to examine differences between these values. Interclass correlation coefficients (ICCs) and interobserver agreement (assessed by calculating kappa coefficients) were calculated to assess the correlation of measures interpreted by two observers. p-values <0.05 were considered significant.

Results

One or more comorbidities were identified in 86.6% of the patients and in 40% of the controls. The most prevalent comorbidity was osteoporosis, present in 44.2% of patients and in 24.8% of controls. New diagnoses of cardiovascular disease, emphysema and osteoporosis were made in 25%, 7% and 46% of cases, respectively. The kappa coefficient for CAC was 0.906 (p<0.001). ICCs for measures of liver, spleen and bone density were 0.88, 0.93 and 0.96, respectively (p<0.001).

Conclusions

CT data acquired during LCS led to the identification of previously undiagnosed comorbidities. The LCS is useful to facilitate comorbidity diagnosis in developing countries, providing opportunities for its prevention and treatment.

Lung cancer screening is useful to facilitate comorbidity diagnosis in developing countries, providing opportunities for its prevention and treatmenthttps://bit.ly/3KEdGuW

Reference values of skeletal muscle area for diagnosis of sarcopenia using chest computed tomography in Asian general population

BACKGROUND

Diagnostic cutoff points for sarcopenia in chest computed tomography (CT) have not been established although CT is widely used for investigating skeletal muscles. This study aimed to determine reference values for sarcopenia of thoracic skeletal muscles acquired from chest CT scans and to analyse variables related to sarcopenia using the cutoff values determined in a general Asian population.

METHODS

We retrospectively reviewed chest CT scans of 4470 participants (mean age 54.8 ± 9.9 years, 65.8% male) performed at a check-up centre in South Korea (January 2016-August 2017). To determine cutoffs, 335 participants aged 19-39 years (mean age 35.2 ± 3.6 years, 75.2% male) were selected as the healthy and younger reference group, and 4135 participants aged ≥40 years (mean age 56.4 ± 8.4 years, 65.1% male) were selected as the study group. We measured the following: cross-sectional area (CSA) of the pectoralis, intercostalis, paraspinal, serratus, and latissimus muscles at the 4^th vertebral region (T4_CSA ); T4_CSA divided by height² (T4MI); pectoralis muscle area (PM_CSA ); and PM_CSA divided by height² (PMI) at the 4^th vertebral region. Sarcopenia cutoff was defined as sex-specific values of less than -2 SD below the mean from the reference group.

RESULTS

In the reference group, T4_CSA , T4MI, PM_CSA , and PMI cutoffs for sarcopenia were 100.06cm² , 33.69cm² /m² , 29.00cm² , and 10.17cm² /m² in male, and 66.93cm² , 26.01cm² /m² , 18.29cm² , and 7.31cm² /m² in female, respectively. The prevalence of sarcopenia in the study group measured with T4_CSA , T4MI, PM_CSA and PMI cutoffs were 11.4%, 8.7%, 8.5%, and 10.1%, respectively. Correlations were observed between appendicular skeletal mass divided by height² measured by bioelectrical impedance analysis (BIA) and T4_CSA (r = 0.82; P < 0.001)/T4MI (r = 0.68; P < 0.001), and ASM/height² measured by BIA and PM_CSA (r = 0.72; P < 0.001)/PMI (r = 0.63; P < 0.001). In the multivariate logistic regression models, sarcopenia defined by T4_CSA /T4MI were related to age [odds ratio (95% confidence interval), P-values: 1.09 (1.07-1.11), <0.001/1.05 (1.04-1.07), <0.001] and diabetes [1.60 (1.14-2.25), 0.007/1.47 (1.01-2.14), 0.043]. Sarcopenia defined by PM_CSA /PMI were related to age [1.09 (1.08-1.10), <0.001/1.05 (1.03-1.06), <0.001], male sex [0.23 (0.18-0.30), <0.001/0.47 (0.32-0.71), <0.001], diabetes [2.30 (1.73-3.05), <0.001/1.63 (1.15-2.32), 0.007], history of cancer [2.51 (1.78-3.55), <0.001/1.61 (1.04-2.48), 0.033], and sufficient physical activity [0.67 (0.50-0.89), 0.007/0.74 (0.56-0.99), 0.042].

CONCLUSIONS

The reference cutoff values of a general population reported here will enable sex-specific standardization of thoracic muscle mass quantification and sarcopenia assessment.

The Value of Artificial Intelligence-Assisted Imaging in Identifying Diagnostic Markers of Sarcopenia in Patients with Cancer

Sarcopenia is defined as the loss of skeletal muscle mass and muscle function. It is common in patients with malignancies and often associated with adverse clinical outcomes. The presence of sarcopenia in patients with cancer is determined by body composition, and recently, radiologic technology for the accurate estimation of body composition is under development. Artificial intelligence- (AI-) assisted image measurement facilitates the detection of sarcopenia in clinical practice. Sarcopenia is a prognostic factor for patients with cancer, and confirming its presence helps to recognize those patients at the greatest risk, which provides a guide for designing individualized cancer treatments. In this review, we examine the recent literature (2017-2021) on AI-assisted image assessment of body composition and sarcopenia, seeking to synthesize current information on the mechanism and the importance of sarcopenia, its diagnostic image markers, and the interventions for sarcopenia in the medical care of patients with cancer. We concluded that AI-assisted image analysis is a reliable automatic technique for segmentation of abdominal adipose tissue. It has the potential to improve diagnosis of sarcopenia and facilitates identification of oncology patients at the greatest risk, supporting individualized prevention planning and treatment evaluation. The capability of AI approaches in analyzing series of big data and extracting features beyond manual skills would no doubt progressively provide impactful information and greatly refine the standard for assessing sarcopenia risk in patients with cancer.

Prognostic Values of Inflammatory Indexes and Clinical Factors in Patients with Epidermal Growth Factor Receptor Mutations in Lung Adenocarcinoma and Treated with Tyrosine Kinase Inhibitors

This study aimed to access the predictive value of inflammatory indices and clinical factors in toxicity and survival in patients with epidermal growth factor receptor (EGFR)-mutated lung adenocarcinoma receiving first-line tyrosine kinase inhibitor (TKI)-treatment. A total of 259 patients with stage IIIB−IV lung adenocarcinoma and actionable EGFR mutation who received first-line TKI treatment between 2008 and 2020 were retrospectively enrolled and analyzed. The prognostic factors of TKI-related toxicity, overall survival (OS), and progression-free survival (PFS) were identified by using logistic regression analysis and Cox proportional hazards models. Pre-TKI high platelet-to-lymphocyte ratio (PLR) was associated with post-TKI anemia. Hypoalbuminemia was associated with acneiform rash. Elderly age (≥70 years) and lower body mass index (<18.5 kg/m2) were also associated with hypoalbuminemia. Elderly age, stage IV, EGFR-mutated with L858R and uncommon mutations, and neutrophil-to-lymphocyte ratio were found to be independent prognostic factors for PFS, while elderly age, uncommon EGFR-related mutations, and lymphocyte-to-monocyte ratio were found to be independent prognostic factors for OS. A useful prognostic scoring tool for improving the survival risk stratification of patients was established by incorporating the above essential factors. Baseline hypoalbuminemia and PLR could be crucial clinical assessment factors when initiating TKI therapy. In addition, the optimization of individualized treatment strategies for these patients may be assisted by using the risk-scoring model.

Inverse association between sarcopenia and displacement in the early phase of fragility fractures of the pelvis

Objectives

Fragility fractures of the pelvis (FFP) commonly occur in the frail elderly. Displacement in the posterior pelvic ring is recognized as the key sign of instability. This study aims to elucidate the relationship between computer tomography (CT)-based frailty markers and displacement of the posterior pelvic ring within 7 days after injury.

Methods

This retrospective study included 49 patients (42 females, 7 males) with FFP (type I 10, type II 24, type III 12, type IV 3). On a CT slice at the level of the third lumbar vertebra, skeletal muscle area, skeletal muscle radiation attenuation, and skeletal muscle index (SMI) were calculated as sarcopenia markers. Osteopenia was measured with trabecular region of interest attenuation technique on the same CT slice.

Results

There was no difference in the demographics between non-displaced and displaced FFP. CT-based data showed that patients with FFP had osteopenia. However, no difference was found between non-displaced and displaced FFP. SMI was higher in FFP types III/IV than non-displaced FFP when CT-based data on sarcopenia were compared among all patients. Female patients with FFP demonstrated similar results. Logistic regression analysis using the demographics and CT-based markers on sarcopenia and osteopenia revealed that SMI was a potential determinant of displacement of the posterior pelvic ring fractures.

Conclusions

There was inverse association between sarcopenia and displacement of the posterior pelvic ring in the early phase of FFP. Relatively preserved muscle may develop displacement in the elderly with osteopenia.

CT evaluation for sarcopenia involving the psoas and paravertebral muscles in patients with total hip arthroplasty

BACKGROUND

Computed tomography (CT) has been validated in diagnosing sarcopenia in various clinical conditions.

AIM

To evaluate the core abdominal muscles in terms of sarcopenia in patients with total hip arthroplasty (THA) with and without complication.

METHODS

Retrospective analysis of patients with a pelvic CT revealed 145 consecutive patients with THA. Also, 118 consecutive cases with normal CT scans constituted the control group. The area and density measurements of bilateral psoas (PSA, psoas area; PSD, psoas density) and paravertebral (PVA, paravertebral area; PVD, paravertebral density) muscles were performed at the level of L3 or L4 vertebrae regardless of prosthesis side. All measurements were evaluated in normal cases and in patients with THA, as well as in patients with complicated prostheses.

RESULTS

In the whole population and subgroup of patients with bilateral THA, bilateral PSA, PSD, and PVD but not the PVA were lower in patients with THA compared to controls (all p < 0.01). In patients with unilateral prostheses, ipsilateral PSA, PSD, and bilateral PVD but not the PVA were lower compared to controls (all p < 0.01). Furthermore, in patients with unilateral prostheses with complication, only ipsilateral PSD was lower compared to patients with unilateral prostheses without complication (all p < 0.05) and in patients with bilateral prostheses with complication, bilateral PSA, PSD, and PVD but not the PVA were lower compared to patients with bilateral prostheses without complication (all p < 0.05).

CONCLUSION

Sarcopenia indicated by the area and density measurements of core abdominal muscles can be associated with the presence and complication of hip prostheses.

Sarcopenia in rheumatic disorders: what the radiologist and rheumatologist should know

Sarcopenia is defined as the loss of muscle mass, strength, and function. Increasing evidence shows that sarcopenia is common in patients with rheumatic disorders. Although sarcopenia can be diagnosed using bioelectrical impedance analysis or DXA, increasingly it is diagnosed using CT, MRI, and ultrasound. In rheumatic patients, CT and MRI allow "opportunistic" measurement of body composition, including surrogate markers of sarcopenia, from studies obtained during routine patient care. Recognition of sarcopenia is important in rheumatic patients because sarcopenia can be associated with disease progression and poor outcomes. This article reviews how opportunistic evaluation of sarcopenia in rheumatic patients can be accomplished and potentially contribute to improved patient care.

Use of computed tomography for the diagnosis of surgical sarcopenia: Review of recent research advances

Sarcopenia, also known as muscle decay, is associated with high morbidity among surgical patients. It is highly correlated with adverse clinical outcomes, such as increased postoperative complications, prolonged hospital stay, and increased mortality. Computed tomography (CT) is one of the main methods for diagnosing sarcopenia, which has the advantages of intuitiveness, rapidity, and accuracy. Clinical studies have shown that CT-defined sarcopenia can help predict the clinical outcomes and prognosis of surgical patients and provide an important reference for the formulation of antitumor treatment protocols. In recent years, some scholars have tried to construct an intelligent CT-based diagnostic model, which is expected to improve the diagnostic efficiency and establish standardized diagnostic criteria for CT-defined sarcopenia. In this review, we summarize the recent progress in the understanding of the diagnosis of sarcopenia and its potential prognostic value in surgery.

Transfer learning for data-efficient abdominal muscle segmentation with convolutional neural networks

Background

Skeletal muscle segmentation is an important procedure for assessing sarcopenia, an emerging imaging biomarker of patient frailty. Data annotation remains the bottleneck for training deep learning auto‐segmentation models.

Purpose

There is a need to define methodologies for applying models to different domains (e.g., anatomical regions or imaging modalities) without dramatically increasing data annotation.

Methods

To address this problem, we empirically evaluate the generalizability of various source tasks for transfer learning: natural image classification, natural image segmentation, unsupervised image reconstruction, and self‐supervised jigsaw solving. Axial CT slices at L3 were extracted from PET‐CT scans for 204 oesophago‐gastric cancer patients and the skeletal muscle manually delineated by an expert. Features were transferred and segmentation models trained on subsets (n=5,10,25,50,75,100,125) of the manually annotated training set. Four‐fold cross‐validation was performed to evaluate model generalizability. Human‐level performance was established by performing an inter‐observer study consisting of ten trained radiographers.

Results

We find that accurate segmentation models can be trained on a fraction of the data required by current approaches. The Dice similarity coefficient and root mean square distance‐to‐agreement were calculated for each prediction and used to assess model performance. Models pre‐trained on a segmentation task and fine‐tuned on 10 images produce delineations that are comparable to those from trained observers and extract reliable measures of muscle health.

Conclusions

Appropriate transfer learning can generate convolutional neural networks for abdominal muscle segmentation that achieve human‐level performance while decreasing the required data by an order of magnitude, compared to previous methods (n=160→10). This work enables the development of future models for assessing skeletal muscle at other anatomical sites where large annotated data sets are scarce and clinical needs are yet to be addressed.

Older cancer patients receiving radiotherapy: a systematic review for the role of sarcopenia in treatment outcomes

BACKGROUND

Previous studies have evaluated the prognostic effects of sarcopenia in cancer patients receiving various treatments, including chemotherapy and surgery, but few studies have focused on radiotherapy (RT).

AIMS

We aimed to investigate the prevalence of sarcopenia and the relationship between sarcopenia and outcomes in older cancer patients who underwent RT without chemotherapy.

METHODS

A systematic review of the literature was conducted in Pubmed/Medline and Cochrane databases in September 2021. We used the search terms and medical subject heading terms "sarcopenia," "low muscle mass (LMM)," "low muscle strength," "LMM and low muscle strength," "LMM and low muscle strength and low physical performance," and "RT." Outcomes were overall survival (OS), progression-free survival, non-cancer death, cancer death, disease-specific survival, local failure-free survival, distant failure-free survival, and RT-related toxicities.

RESULTS

Among 460 studies, 8 studies were eligible for inclusion. The prevalence of sarcopenia was between 42.8% and 72%. Sarcopenia was not associated with OS or OS at 3 years in seven studies in which it was defined as the presence of LMM, while it was related in one study, in which it was defined as the concomitant presence of LMM and muscle strength/function.

DISCUSSION

There was heterogeneity between the studies because there was diversity in their inclusion criteria, definition and assessment methods used for detection of sarcopenia, considered cutoffs for low muscle mass and strength, cross-sectional locations on imaging to assess muscle mass and included covariates. The discrepancy in the results of the studies may also result from the variations in diagnoses, sample sizes, and treatment modalities. The low number of included studies and a small number of patients in each study limited generalizability.

CONCLUSIONS

Sarcopenia may be a prognostic factor, especially in OS when low muscle strength/function is integrated into its definition. We suggest that clinicians focus on muscle strength/function while considering sarcopenia and its association with cancer and RT-related outcomes.