Muscle Density Research Articles

Association Between Changes in Skeletal Muscle Quality and Prognosis in Postoperative Patients with Early Gastric Cancer.

Identifying accurate prognostic factors is crucial for postoperative management of early gastric cancer (EGC) patients. Skeletal muscle quality (SMQ), defined by muscle density on computed tomography (CT) images, has been proposed as a novel prognostic factor. This study compared the prognostic significance of SMQ changes with the well-established factor of body weight (BW) loss in the postoperative EGC setting. This single-center retrospective study included 297 postoperative EGC patients (median age 69 years, 68.4% male) who had preoperative and 1-year-postoperative gastrectomy CT images. SMQ was defined as the modified intramuscular adipose tissue content (mIMAC = skeletal muscle density-subcutaneous fat density on CT images) and the change as ΔmIMAC. Log-rank test, Kaplan-Meier survival, and Cox proportional hazards regression analyses were used to assess the associations between prognosis and either ΔmIMAC or BW change (ΔBW). Prognosis prediction by ΔmIMAC and ΔBW was compared by using the area under the curve (AUC) of the receiver operating characteristic curve. ΔmIMAC was significantly associated with prognosis (log-rank test; P = 0.037), but ΔBW was not (P = 0.243). Prognosis was significantly poorer in the severely decreased mIMAC group than in the preserved group (multivariate Cox proportional hazards regression analysis; P = 0.030) but was unaffected by BW changes (P = 0.697). The AUC indicated a higher prognostic value for ΔmIMAC than ΔBW (ΔmIMAC: AUC = 0.697, ΔBW: AUC = 0.542). One-year post-gastrectomy SMQ changes may be better prognostic EGC predictors than BW changes.

Correlation of Sarcopenia with Coronary Artery Disease Severity and Pericoronary Adipose Tissue Attenuation: A Coronary CT Study

Objective: To investigate the association between sarcopenia, as appraised with CT-derived muscle metrics, and cardiovascular status, as assessed via coronary CT angiography (CCTA) using the Coronary Artery Disease-Reporting and Data System (CAD-RADS) and with pericoronary adipose tissue (pCAT) metrics. Methods: A retrospective observational study conducted on patients who underwent CCTA. The cross-sectional area (CSA) and attenuation values of the paravertebral muscles at the T8 level and the pectoralis major muscles at the T6 level were measured. The patient height was employed for the normalization of the skeletal muscle CSA. The pCAT attenuation around the coronary arteries was assessed, and the CAD severity was graded using the CAD-RADS reporting system. Regression analyses were performed to assess the impact of demographics, clinical factors, and CT variables on the CAD-RADS and pCAT. Results: A total of 220 patients were included (132 males, median age 65 years). Regression analyses showed the associations of CAD with age and sex (p < 0.001). Familiarity with CAD was related to the left anterior descending artery pCAT (p = 0.002) and circumflex artery pCAT (p = 0.018), whereas age was related to the left anterior descending artery pCAT (p = 0.032). Weak positive correlations were found between the lower muscle density and lower pCAT attenuation (ρ = 0.144–0.240, p < 0.039). Conclusions: This study demonstrated weak associations between the sarcopenia indicators and the cardiovascular risk, as assessed by the CAD severity and pCAT inflammation. However, these correlations were not strong predictors of CAD severity, as age and traditional cardiovascular risk factors overshadowed the impact of sarcopenia in the cardiovascular risk assessment.

Beyond MELD Score: Association of Machine Learning-derived CT Body Composition with 90-Day Mortality Post Transjugular Intrahepatic Portosystemic Shunt Placement.

To determine the association of machine learning-derived CT body composition and 90-day mortality after transjugular intrahepatic portosystemic shunt (TIPS) and to assess its predictive performance as a complement to Model for End-Stage Liver Disease (MELD) score for mortality risk prediction. This retrospective multi-center cohort study included patients who underwent TIPS from 1995 to 2018 and had a contrast-enhanced CT abdomen within 9months prior to TIPS and at least 90 days of post-procedural clinical follow-up. A machine learning algorithm extracted CT body composition metrics at L3 vertebral level including skeletal muscle area (SMA), skeletal muscle index (SMI), skeletal muscle density (SMD), subcutaneous fat area (SFA), subcutaneous fat index (SFI), visceral fat area (VFA), visceral fat index (VFI), and visceral-to-subcutaneous fat ratio (VSR). Independent t-tests, logistic regression models, and ROC curve analysis were utilized to assess the association of those metrics in predicting 90-day mortality. A total of 122 patients (58 ± 11.8, 68% male) were included. Patients who died within 90 days of TIPS had significantly higher MELD (18.9 vs. 11.9, p < 0.001) and lower SMA (123 vs. 144.5, p = 0.002), SMI (43.7 vs. 50.5, p = 0.03), SFA (122.4 vs. 190.8, p = 0.009), SFI (44.2 vs. 66.7, p = 0.04), VFA (105.5 vs. 171.2, p = 0.003), and VFI (35.7 vs. 57.5, p = 0.02) compared to those who survived past 90 days. There were no significant associations between 90-day mortality and BMI (26 vs. 27.1, p = 0.63), SMD (30.1 vs. 31.7, p = 0.44), or VSR (0.97 vs. 1.03, p = 0.66). Multivariable logistic regression showed that SMA (OR = 0.97, p < 0.01), SMI (OR = 0.94, p = 0.03), SFA (OR = 0.99, p = 0.01), and VFA (OR = 0.99, p = 0.02) remained significant predictors of 90-day mortality when adjusted for MELD score. ROC curve analysis demonstrated that including SMA, SFA, and VFA improves the predictive power of MELD score in predicting 90-day mortality after TIPS (AUC, 0.84; 95% CI: 0.77, 0.91; p = 0.02). CT body composition is positively predictive of 90-day mortality after TIPS and improves the predictive performance of MELD score. Level 3, Retrospective multi-center cohort study.

Skeletal muscle size and quality in healthy kidney donors, normal range and clinical associations

The gold standard to estimate muscle mass and quality is computed tomography (CT) scan. Lower mass and density (intramuscular fat infiltration) of skeletal muscles are markers of sarcopenia, associated with increased mortality risk, impaired physical function, and poorer prognosis across various populations and medical conditions. We aimed to describe standard reference values in healthy population, prospective kidney donors, and correlate clinical parameters to muscle mass and density. Included in the cohort 384 consecutive kidney donors. Mean age was 44.6 ± 11.5 (range 18.4–74.2), 46% were female and mean BMI was 25.6 ± 3.8 kg/m2. Our quantified reference values for psoas cross -sectional area (CSA) index at L3 level (males/females respectively) were 6.3 ± 1.8 and 4.8 ± 1.9 cm2 /m2, and density was 46.1 ± 5 and 41 ± 5 HU at that level. Older age (standardized beta coefficient − 0.12, p = 0.04), sex (− 0.32, p < 0.001) and BMI (0.17, p = 0.002) were significantly associated with CSA index of psoas at L3. Density, however, was associated with triglycerides level (− 0.21, p < 0.001), in addition to age (− 0.22, p < 0.0001), sex (− 0.27, p < 0.001) and BMI (− 0.1, p = 0.05). Our study validates the normative values of psoas muscle mass and density in healthy individuals and suggests correlations with clinical parameters. We demonstrate the significance of measuring not only the mass of the muscle, but also its density, as it has a valid association with metabolic parameters, including BMI and lipid level, even in healthy individuals and in the normal range of the tests.

CT-based sarcopenia assessment: Predicting outcomes in acute infection patients.

In this retrospective cohort study, we investigated the prognostic value of sarcopenia evaluated by Computed Tomography (CT)-based indices for adverse hospitalization outcomes in patients with acute infections. We analyzed data from 225 patients admitted to the hospital for acute infections between 2019 and 2020. Patients who had undergone an abdominal CT scan either up to 1 month before or within the first 3 days of hospitalization were included. CT image analysis was used to evaluate skeletal muscle mass (by skeletal muscle index (SMI)) and muscle quality (by psoas muscle density, pMD). Low pMD was associated with higher in-hospital mortality (31% vs 11.4% p < 0.001) as well as higher longer-term mortality rates (p = 0.008 for 30 days and <0.001 for 90- and 1-year mortality). Low pMD remained an independent poor prognostic factor after controlling for confounders, with an adjusted odds ratio (aOR) of 2.74, (95% CI 1.33-5.67, p = 0.006) for 1-year mortality, and aOR of 2.61, (95% CI 1.23-5.55) for a prolonged hospital stay. Low SMI was associated with adverse outcomes, although this association was not independent after controlling for confounders. Notably, patients with both low SMI and pMD exhibited the poorest hospitalization outcomes: aOR for 1-year mortality 5.015 (95% CI 1.767-14.23, p = 0.002), and prolonged length of stay aOR 3.197, (95% CI 1.159-8.821, p = 0.025). CT-based muscle indices serve as independent prognostic factors in medical patients admitted with acute infection. Incorporating radiological assessments of sarcopenia into routine care for hospitalized patients with acute infection may enable risk stratification and early intervention in reversible conditions.

Psoas Muscle Index and Density as Prognostic Predictors in Patients Hospitalized with Acute Pancreatitis

Background: Early prognostication of acute pancreatitis (AP) patients for those at high risk of complications during hospitalization can facilitate clinical decision-making. Sarcopenia has been proven to be a risk factor for poor prognosis in patients with AP. We aimed to evaluate the association between the muscle parameters measured in computed tomography (CT) and the clinical outcomes of hospitalized patients with AP. Methods: A total of 132 consecutive patients hospitalized between 1 January 2015 and 31 December 2021 for AP with a valid CT scan were analyzed. The first CT conducted during hospitalization was analyzed for psoas muscle area (PMA), index (PMI), and density (PMD) at the L3 vertebral level. The main adverse outcomes indicating a worse prognosis were the development of extrapancreatic complications, infections, ICU transfer, in-hospital mortality, and hospitalization length. Results: The lowest tertile of PMI, as a surrogate for sarcopenia, was significantly correlated with increased rates of extrapancreatic complications, infections, and longer hospitalizations. It was additionally correlated with a worse CT severity index. The results for PMA and PMD also showed worse outcomes, largely mirroring the results for PMI. Although in-hospital mortality was relatively low, none of the patients died in the highest tertile of PMI. A clear cutoff with sufficient predictive capability could not be found. Conclusions: A low psoas muscle index can serve as an additional potential predictive marker for more severe disease and worse outcomes in hospitalized acute pancreatitis patients. More studies are needed to determine its combination with existing prediction tools.

Muscular Hypertrophy and its Relation to Strength Performance: A Physics-Based Analysis of Conceptual Inaccuracies

ABSTRACT The interchangeable use of terms such as muscle mass, volume, cross-sectional area, and thickness in discussions on the physiology of muscle hypertrophy has led to misconceptions in research and practice. This review aims to highlight the improperness of this approach and highlights the overlooked parameter of muscular density (MD). The hypothesis is that muscle density acts as a mediator, leading to inevitable muscle enlargement in long-term strength training. It is proposed that research in muscular adaptations to training should implement measures of MD to complement measurements of muscle size. This article aims to refine the understanding of muscular adaptations and optimize training strategies for athletes and fitness enthusiasts.

Visceral Obesity and Its Association with Severe Coronary Artery Calcification in Patients with Metabolic Dysfunction-Associated Steatotic Liver Disease.

Background/Objectives: The role of body composition parameters in patients with metabolic dysfunction-associated steatotic liver disease (MASLD) with presence and severity of coronary artery calcification (CAC) is still not fully elucidated. We aimed to evaluate the impact of computed tomography (CT)-based body composition parameters in patients with MASLD with CAC severity. Methods: In this multicenter study, 1870 individuals underwent cardiac CT for the detection of CAC as well as ultrasonography for the diagnosis of hepatic steatosis. The presence of CAC was defined by a CAC score threshold of >0, while severe CAC was defined by a threshold of >300. Using the abdominal cross-sectional CT images at the L3 vertebra level, we analyzed the skeletal muscle index, visceral to subcutaneous adipose tissue ratio, and muscle density using the Hounsfield unit. Results: Of 648 patients with MASLD, the proportions of presence of CAC and severe CAC were 45.2% and 9.9%, respectively. Visceral obesity was not associated with the presence of CAC after adjustment for age, sex, smoking, statin therapy, type 2 diabetes, and advanced fibrosis (adjusted odds ratio (aOR), 1.38; 95% confidence interval (CI), 0.86-2.23; p = 0.180). However, visceral obesity was independently associated with severe CAC after adjustment for several metabolic risk factors (aOR, 3.54; 95% CI, 1.25-14.90; p = 0.039), and adjustment for atherosclerotic cardiovascular disease risk scores (aOR, 3.74; 95% CI, 1.31-15.79; p = 0.032). Conclusions: Visceral obesity may serve as a novel prognostic CT-based radiological biomarker for patients with MASLD with severe CAC.

Body Composition Decrease and Impact on Clinical Outcome in Gastric Cancer Patients Undergoing Radical Gastrectomy After Neoadjuvant Treatment

This study investigates the impact of neoadjuvant therapy (NT) on body composition and its correlation with long-term survival and other clinical outcomes in patients with advanced gastric cancer. We utilized Computed Tomography (CT) scans to measure body composition before and after NT, including Subcutaneous Adipose Tissue Index (SATI), Visceral Adipose Tissue Index (VATI), Skeletal Muscle Index (SMI), and Muscle Density (MA). We then analyzed the decrease in body composition in relation to tumor regression, inflammatory markers, nutritional scores, and long-term survival. Our findings reveal a negative correlation between the decrease in SATI and VATI after NT, and both tumor regression and nutritional score. Notably, patients who experienced a significant loss in SATI or VATI post-NT had shorter Recurrence-Free Survival (RFS) and Overall Survival (OS). Additionally, significant loss in SATI and VATI emerged as an independent risk factor for both RFS and OS. In conclusion, our study convincingly demonstrates that in patients with advanced gastric cancer, SATI and VATI decreases after NT and is negatively associated with tumor regression and nutritional score. A significant loss in SATI and VATI is a risk factor for shorter RFS and OS, thereby underscoring the importance of maintaining body composition during NT.

Intestinal Region-Dependent Impact of NFκB-Nrf Crosstalk in Myenteric Neurons and Adjacent Muscle Cells in Type 1 Diabetic Rats.

Type 1 diabetes affects cytokines as potential inducers of NFκB signalling involved in inflammation and neuronal survival. Our goal was to assess the expression of NFκB p65 and its negative regulator, Nrf2, in myenteric neurons and adjacent smooth muscle of different gut segments after chronic hyperglycaemia and immediate insulin treatment. After ten weeks of hyperglycaemia, intestinal samples of control, streptozotocin-induced diabetic and insulin-treated diabetic rats were prepared for fluorescent immunohistochemistry, immunogold electron microscopy, ELISA and qPCR. In the diabetic rats, the proportion of NFκB p65-immunoreactive myenteric neurons decreased significantly in the duodenum and increased in the ileum. The density of NFκB p65-labelling gold particles increased in the ileal but remained unchanged in the duodenal ganglia. Meanwhile, both total and nuclear Nrf2 density increased in the myenteric neurons of the diabetic duodenum. In smooth muscle, NFκB p65 and Nrf2 density increased in the small intestine of diabetic rats. While on the mRNA level, NFκB p65 and Nrf2 were induced, on the protein level, NFκB p65 increased and Nrf2 decreased in muscle/myenteric plexus homogenates. Insulin treatment had protective effects. Our findings reveal a segment-specific NFκB and Nrf expression in myenteric neurons and ganglionic muscular environments, which may contribute to regional neuronal survival and motility disturbances in diabetes.

Myosteatosis and sarcopenia are linked to autonomous cortisol secretion in patients with aldosterone-producing adenomas.

Patients with adrenal aldosterone-producing adenomas (APA) face elevated cardiovascular risks, especially when cortisol is co-secreted, yet the impact on muscle health remains unclear. Myosteatosis, characterized by fatty infiltration into muscles, is linked to cardiometabolic diseases and decreased survival. We aimed to investigate the association between autonomous cortisol secretion (ACS) in APA and muscle quantity and quality. In this study, we analyzed data from 228 APA patients undergoing laparoscopic adrenalectomy between 2009 and 2024, assessing muscle composition via computed tomography. Intermuscular adipose tissue (IMAT), skeletal muscle area and density, visceral and subcutaneous adipose tissue area at L3 were measured. Comparisons were made between ACS and non-ACS groups. We found that among 228 patients, 76 (33.3%) had ACS. Those with ACS exhibited significantly higher IMAT area (P = 0.042) and lower skeletal muscle area (P = 0.002) and density (P < 0.001). Multivariable regression confirmed ACS positively associated with IMAT area and negatively associated with skeletal muscle area and density. At 1-year follow-up, ACS patients (n = 15) experienced decreased IMAT area (P = 0.001) and increased skeletal muscle area (P = 0.031) post-adrenalectomy, while those without ACS (n = 29) showed no IMAT change but increased visceral (P < 0.001) and subcutaneous (P = 0.008) adipose tissue area. In summary, myosteatosis and sarcopenia are linked to ACS in APA patients, and these parameters improve following adrenalectomy.

Body Composition and Progression of Biopsy-Proven Non-Alcoholic Fatty Liver Disease in Patients With Obesity.

Obesity is a significant risk factor for the progression of non-alcoholic fatty liver disease (NAFLD). However, a convenient and efficacious non-invasive test for monitoring NAFLD progression in patients with obesity is currently lacking. This study aims to investigate the associations between CT-based body composition and the progression of biopsy-proven NAFLD in patients with obesity. Liver biopsy was conducted in patients with obesity, and the progression of NAFLD was evaluated by the NAFLD activity score (NAS). Body composition was assessed through abdominal computed tomography (CT) scans. A total of 602 patients with an average age of 31.65 (±9.33) years old were included, comprising 217 male patients and 385 female patients. The wall skeletal muscle index (SMI), total SMI, and visceral fat index (VFI) were positively correlated with NAS in both male and female patients. Multivariate regression analysis demonstrated significant associations between high liver steatosis and wall SMI (HR: 1.60, 95% CI: 1.12 to 2.30), total SMI (HR: 1.50, 95% CI: 1.02 to 2.08), VSI (HR: 2.16, 95% CI: 1.48 to 3.14), visceral fat to muscle ratio (HR: 1.51, 95% CI: 1.05 to 2.18), and visceral to subcutaneous fat ratio (HR: 1.51, 95% CI: 1.07 to 2.12). Non-alcoholic steatohepatitis (NASH) was significantly associated with wall SMI (HR: 1.52, 95% CI: 1.06 to 2.19) and VSI (HR: 1.50, 95% CI: 1.03 to 2.17). Liver fibrosis ≥ F2 was significantly associated with psoas muscle index (HR: 0.64, 95% CI: 0.44 to 0.93) and psoas skeletal muscle density (HR: 0.61, 95% CI: 0.41 to 0.89). Our study suggested that certain CT-based body composition indicators, notably high VFI, were significantly associated with the progression of NAFLD in patients with obesity. Great attentions and timely managements should be given to these patients with body composition characteristics associated with the risk of NAFLD progression.

The prognostic value of skeletal muscle mass and density in breast cancer: a systematic review and meta-analysis.

Aim: The effect of skeletal muscle mass and density on the long-term survival outcome of breast cancer patients is unclear.Materials & methods: Systematically searched all articles in PubMed, Web of science, Springerlink, EMBASEand Wiley databases that studied the association between skeletal muscle and survival outcomes of breast cancer by 25September 2023. The hazard ratios and confidence intervals of the multiple factor analysis results controlling for confounding variables in the study were collected and analyzed using STATA 14.0 software.Results: This meta-analysis included a total of 13 studies, with a median age of 48.2years. Meta results showed that the survival (hazard ratio [HR]: 0.98, 95% CI: 0.89-1.08) and recurrence (HR: 0.96, 95% CI: 0.92-1.00) outcomes of breast cancer patients with sarcopenia were not significantly affected compared with those without sarcopenia. No significant heterogeneity or publication bias was observed in the study.Conclusion: The conclusion that skeletal muscle is regarded as a useful factor that can guide and optimize the prognosis of breast cancer patients is uncertain, or the result is very weak. Considering the impact of research quality and confounding factors, prospective studies are needed in the future to further demonstrate.PROSPERO identifier: CRD42023463480 (www.crd.york.ac.uk/prospero).

Effects of over 10 weeks of resistance training on muscle and bone mineral density in older people with sarcopenia over 70 years old: A systematic review and meta-analysis of randomized controlled trials

ObjectiveWe aimed to examine the effects of more than 10 weeks of resistance training (RT) on muscle structure, muscle function, and bone mineral density (BMD) in older people with sarcopenia over 70 years old MethodsPubMed, Web of Science, Embase, MEDLINE, Cochrane Library, and CINAHL databases were searched for randomized controlled trials. Standardized mean difference (MD) or standard mean difference (SMD) was used to pool the effect of the RT intervention ResultsThirteen studies with 2080 older adults with sarcopenia were included. Resistance exercise significantly affected handgrip strength (MD = 1.67 kg; P = 0.02) and isometric muscle strength (standard mean difference [SMD] = 0.53; P = 0.02). Significant differences in chair stand test (SMD = 0.40; P = 0.02) and skeletal muscle mass index (mean difference [MD] = 1.67 kg/m2; P = 0.0002) were found between the RT and control groups ConclusionMore than 10 weeks of RT has beneficial effects on muscle but no favorable effect on BMD in older people with sarcopenia over 70 years old.

Skeletal muscle-derived exosomes selectively coated miRNAs and participate in myoblast proliferation and differentiation mediated by miR-4331-3p

The phenotypic characteristics and meat quality of skeletal muscles are collectively determined by muscle cells and their intricate interactions with the extracellular microenvironment. In this study, we evaluated muscle fiber phenotypes in the longissimus dorsi (HC-L) and psoas major (HC-P) of Hechuan black pigs. The results revealed significant differences in muscle fiber diameter, density, and type (P < 0.05). Subsequently, co-culture experiments with myoblasts demonstrated that skeletal muscle-derived exosomes (SKM-Exos) promoted myoblast proliferation and differentiation with P-Exo exhibiting superior efficacy in promoting the augmentation of MyHCIIa fiber. Furthermore, SKM-Exos are inherently heterogeneous, and the microRNAs (miRNAs) present in SKM-Exos are selectively coated. Notably, the expression of miR-4331-3p was significantly higher in SKM-Exos than in the corresponding skeletal muscles. The expression of miR-4331-3p was significantly elevated in the SKM-Exos of HC-L compared to that of HC-P, and it interacted with differentially expressed genes between HC-L and HC-P. Moreover, miR-4331-3p enhanced myoblast proliferation and inhibited differentiation. Our findings offer valuable insights into the molecular processes that contribute to meat formation, including intricate cellular interactions.

Skeletal muscle density as a new predictor of abdominal infection in abdominal trauma patients

Background and aimsSkeletal muscle density (SMD) is a valuable prognostic indicator in various conditions such as cancer, liver cirrhosis. Yet, the connection between SMD and intra-abdominal infection in individuals who have suffered abdominal injuries is still unclear. The purpose of this research is to examine how well SMD can predict intra-abdominal infection in patients who have suffered abdominal trauma. MethodsParticipants with abdominal injuries were included in this research from January 2015 to April 2023. Based on the sex-specific cut off values of SMD, the entire population was split into two categories. Prognostic factors were identified through logistic regression analysis. ROC was used to assess the predictive accuracy of SMD and its combinations with other biomarkers for clinical outcomes. ResultsA total of 220 patients were ultimately included in the study. Patients in the group with low SMD exhibited a higher incidence of intra-abdominal infection, longer hospital stays, and increased hospital costs. In patients with abdominal trauma, low SMD was identified as a significant independent predictor of intra-abdominal infection (OR 2.397; 95% CI 1.117- 5.141, p = 0.025). Low SMD had a higher area under the curve (AUC) in ROC analysis compared to TRF, NRS2002 score, and APACHEII score for predicting intra-abdominal infection (AUC 0.70, 95% CI 0.61-0.78, p = 0.002). Moreover, low SMD showed associations with clinical outcomes such as hospital stay length and costs (p < 0.01). ConclusionsLow SMD is recognized as an independent risk factor for predicting intra-abdominal infections in this patient population. Notably, SMD is emerging as a novel predictor of abdominal infections in patients with abdominal trauma.

Muscle Density Changes in CKD and Clinical Outcomes

Muscle Density Changes in CKD and Clinical Outcomes

Can Psoas muscle density predict the development of metastasis in non-metastatic adrenocortical carcinomas?: A CT-based AI-assisted automated segmentation analysis study

Aim: Our study aimed to investigate whether artificial intelligence-based body composition analysis can predict metastasis development during follow-up in patients with non-metastatic adrenocortical carcinoma (ACC) at the time of diagnosis. Methods: Forty-five patients with non-metastatic ACC were included at the time of diagnosis. From the patients' non-contrast computed tomography (CT) scans, visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), psoas area, psoas density, total muscle area, and total muscle density were automatically measured from sections taken at the level of the inferior endplate of the L3 vertebra. Patients were followed for developing liver, lung, and lymph node metastases. The relationship between body composition and liver and lymph node metastasis development was investigated. Propensity score matching (PSM) was performed for patients with metastases. Results: Forty-five patients, 27 of whom were female, with non-metastatic ACC at the time of diagnosis, were included in the study. The mean age of the patients was 53±17.4 years. Significant differences were found between the groups that developed liver metastases and those that did not, and between the groups that developed lymph node metastases and those that did not, in terms of correct Psoas HU, left Psoas HU, PMD, Wall Muscle HU, and age (p

Correlation of HbA1c levels with CT-based body composition biomarkers in diabetes mellitus and metabolic syndrome

Diabetes mellitus and metabolic syndrome are closely linked with visceral body composition, but clinical assessment is limited to external measurements and laboratory values including hemoglobin A1c (HbA1c). Modern deep learning and AI algorithms allow automated extraction of biomarkers for organ size, density, and body composition from routine computed tomography (CT) exams. Comparing visceral CT biomarkers across groups with differing glycemic control revealed significant, progressive CT biomarker changes with increasing HbA1c. For example, in the unenhanced female cohort, mean changes between normal and poorly-controlled diabetes showed: 53% increase in visceral adipose tissue area, 22% increase in kidney volume, 24% increase in liver volume, 6% decrease in liver density (hepatic steatosis), 16% increase in skeletal muscle area, and 21% decrease in skeletal muscle density (myosteatosis) (all p < 0.001). The multisystem changes of metabolic syndrome can be objectively and retrospectively measured using automated CT biomarkers, with implications for diabetes, metabolic syndrome, and GLP-1 agonists.

Muscle Quality and Physical Function in Men With and Without HIV.

People with HIV (PWH) experience faster physical decline than those without HIV (PWoH), despite antiretroviral therapy. We compared skeletal muscle density and area and their relationship with physical function among PWH and PWoH. Quantitative computed tomography scans were performed at the L4-L5 spinal region and the thigh to evaluate muscle groups in Multicenter AIDS Cohort Study participants at baseline. Using exploratory factor analysis, we summarized aggregated muscle measures based on factor loadings. Longitudinal associations between muscle area and density with gait speed and grip strength were examined using multivariable linear regression models with generalized estimating equations, adjusting for demographics, HIV serostatus, and other health metrics. We included 798 men (61% of PWH). The median age was 54 years (interquartile range: 49-59), 61% were White, 32% Black, and 10% Hispanic. Among them, 22% had a body mass index over 30kg/m2, and 14% had diabetes. Two factors emerged from the factor analysis explaining 55.9% of variance. Factor 1 (explained 32.5% of variance) encompassed all density measures. Factor 2 (explained 23.4% of variance) encompassed all area measures. Associations between muscle density and gait speed were more pronounced with aggregated measures than with individual ones. Specifically, each unit increase in overall muscle density correlated with a 0.028 m/s increase in gait speed (95% confidence interval [CI]: 0.017, 0.038, p < .01). Grip strength was associated with aggregated measures of both muscle density and area, with overall muscle density associated with a 1.88kg increase in grip strength (95% CI: 1.29, 2.46, p < .01), and overall muscle area with a 1.60kg increase (95% CI: 1.02, 2.19, p < .01). Aggregated muscle density and area measurements were significantly associated with physical function. These correlations underscore the importance of interventions to enhance skeletal muscle to improve healthy aging for PWH and PWoH.