Level Of Lumbar Vertebra Research Articles

238. ESOPHAGOGASTRIC ADENOCARCINOMA PATIENTS WITH SARCOPENIA BEFORE OR AFTER NEOADJUVANT CHEMOTHERAPY ARE MORE LIKELY TO HAVE LONGER POST-OPERATIVE INPATIENT STAYS

Abstract Background Sarcopenia is defined as a loss of skeletal muscle mass and function. It is prevalent amongst patients with esophagogastric adenocarcinoma (EGA) and associated with adverse treatment outcomes. The majority of this evidence comes from populations with squamous cell carcinoma or where neoadjuvant chemoradiotherapy was used. Protracted inpatient stays are directly associated with adverse events such as healthcare-associated infections and patient deconditioning and increase the economic burden on healthcare institutions. Methods Patients diagnosed with EGA between January 2017 and December 2021 and undergoing neoadjuvant chemotherapy (NAC) followed by esophagectomy from a single tertiary center in the UK had their pre- and post-NAC CT scans assessed for radiological sarcopenia. Skeletal muscle index (SMI) was calculated from muscle area measured on CT scans at the level of third lumbar vertebra. Previously published SMI cut off values for radiologically defined sarcopenia were used (52.4 cm2 for men and 38.5 cm2 for women). Wilcoxon signed-rank test for non-parametric data was used to determine significance. Results 191 patients were included in the analysis. The number of patients with sarcopenia increased from 96 to 123 following NAC. Sarcopenia before (p = 0.047) or after (p = 0.007) NAC was significantly associated with longer inpatient stays post-operatively. The median stay for patients with sarcopenia before or after NAC was 12 days compared to 9 for those without sarcopenia before or after NAC. Conclusion Radiological sarcopenia is highly prevalent in this cohort of patients and increases following NAC. This study demonstrates that sarcopenia before or after NAC in patients with EGA undergoing esophagectomy are likely to have longer inpatient stays following surgery. Peri-operative treatment to treat and reduce the incidence of sarcopenia should be trialed with the aim of improving post-operative outcomes in this cohort.

Pediatric body composition based on automatic segmentation of computed tomography scans: a pilot study

BackgroundBody composition during childhood may predispose to negative health outcomes later in life. Automatic segmentation may assist in quantifying pediatric body composition in children.ObjectiveTo evaluate automatic segmentation for body composition on pediatric computed tomography (CT) scans and to provide normative data on muscle and fat areas throughout childhood using automatic segmentation.Materials and methodsIn this pilot study, 537 children (ages 1–17 years) who underwent abdominal CT after high-energy trauma at a Dutch tertiary center (2002–2019) were retrospectively identified. Of these, the CT images of 493 children (66% boys) were used to establish normative data. Muscle (psoas, paraspinal and abdominal wall) and fat (subcutaneous and visceral) areas were measured at the third lumbar vertebral (L3) level by automatic segmentation. A representative subset of 52 scans was also manually segmented to evaluate the performance of automatic segmentation.ResultsFor manually-segmented versus automatically-segmented areas (52 scans), mean Dice coefficients were high for muscle (0.87–0.90) and subcutaneous fat (0.88), but lower for visceral fat (0.60). In the control group, muscle area was comparable for both sexes until the age of 13 years, whereafter, boys developed relatively more muscle. From a young age, boys were more prone to visceral fat storage than girls. Overall, boys had significantly higher visceral-to-subcutaneous fat ratios (median 1.1 vs. 0.6, P<0.01) and girls higher fat-to-muscle ratios (median 1.0 vs. 0.7, P<0.01).ConclusionAutomatic segmentation of L3-level muscle and fat areas allows for accurate quantification of pediatric body composition. Using automatic segmentation, the development in muscle and fat distribution during childhood (in otherwise healthy) Dutch children was demonstrated.

Sarcopenia as a Predictor of Prognosis and Risk of Recurrence in Patients Following Curative Treatment for Hepatocellular Carcinoma

Purpose This study is designed to evaluate the prognostic value of sarcopenia as a predictive method for survival of patients with hepatocellular carcinoma (HCC) who will receive curative treatment. Methods To determine the influence of sarcopenia on prognosis, skeletal muscle index (SMI) was measured using computed tomography at the level of the third lumbar vertebra of 100 patients who underwent radiofrequency for hepatocellular carcinoma (HCC). They were followed up for at least 7 months and overall survival and recurrence were identified. We defined sarcopenia using cutoff values for SMI as less than 43.75cm /m for men and 41.10cm /m for women. Results Sarcopenia was present in 54 of 100 patients and correlated significantly with low body mass index (BMI) and DM. Sarcopenia and MELD Na score were significantly associated with poor survival of the patients. Conclusions The study concluded that sarcopenia seemed to have a negative impact on OS in patients with HCCs. Sarcopenia could significantly increase the incidence rates of post-treatment recurrence and overall complications in patients with HCCs.

A Novel Ultrasound Software System for Lumbar Level Identification in Obstetric Patients

(Can J Anaesth. 2022;69:1211–1219) Manual palpation is the primary method that obstetric anesthesiologists use to identify the optimal point of neuraxial anesthesia placement. As it is unreliable, especially when performed in patients with a higher body mass index (BMI), lumbar ultrasound (LUS) is an intriguing option. LUS for neuraxial labor anesthesia and analgesia has improved accuracy in lumbar vertebral level identification and improved first-pass success rate. Despite potential LUS benefits, many physicians continue using manual palpation because they are not proficient in the technical skills required to perform or interpret LUS images. To make LUS simpler and more user-friendly, automated ultrasound software known as Spine Level Identification (SLIDE) system was developed. SLIDE automatically identifies vertebral landmarks in real-time as the ultrasound transducer moves over the skin. This study aimed to determine whether SLIDE accurately identifies the L3-L4 intervertebral space in healthy term parturient women compared with the manual palpation method.

Myosteatosis as a prognostic factor of Mycobacterium avium complex pulmonary disease

Quantitative body composition affects the prognosis of patients with Mycobacterium avium complex pulmonary disease (MAC-PD). However, whether the qualitative body composition obtained indirectly through computed tomography (CT) affects their prognosis is debatable. We retrospectively analyzed patients with MAC-PD who underwent non-contrast CT at MAC-PD diagnosis. The cross-sectional area of the erector spinae muscle (ESM area), the Hounsfield unit of the erector spinae muscle (ESM HU), and the cross-sectional area of subcutaneous fat (SQF area) were measured at the level of the first lumbar vertebra. Myosteatosis were defined below the median value of ESM HU for each sex. Of 377 patients, 45 (11.9%) died during the follow-up. Patients who died were older and had a lower ratio of females (33.3%). In body compositions, SQF area and ESM HU were lower in the patients who died. In multivariable analysis, a low ESM HU was associated with increased mortality (ESM HU adjusted hazard ratio [aHR] 0.95, 95% confidence interval [CI] 0.93–0.97) through body composition. SQF area revealed protective effects in MAC-PD patients with body mass index ≥ 18.5 kg/m2 (aHR 0.98, 95% CI 0.95–1.00). In conclusion, the decrease in ESM HU, which indirectly reflects myosteatosis, is associated with mortality in patients with MAC-PD.

Body composition parameters correlate with the endoscopic severity in Crohn's disease patients treated with infliximab.

The disease activity status and behavior of Crohn's disease (CD) can reflect the severity of the disease, and changes in body composition are common in CD patients. The aim of this study was to investigate the relationship between body composition parameters and disease severity in CD patients treated with infliximab (IFX). Patients with CD assessed with the simple endoscopic score (SES-CD) and were treated with IFX were retrospectively collected, and body composition parameters at the level of the 3rd lumbar vertebrae were calculated from computed tomography (CT) scans of the patients. The correlation of patients' body composition parameters with disease activity status and disease behavior was analyzed, and the diagnostic value of the relevant parameters was assessed using receiver operating characteristic (ROC) curves. A total of 106 patients were included in this study. There were significant differences in the subcutaneous adiposity index (SAI) (p = 0.010), the visceral adiposity index (VAI) (p < 0.001), the skeletal muscle mass index (SMI) (p < 0.001), and decreased skeletal muscle mass (p < 0.001) among patients with different activity status. After Spearman and multivariate regression analysis, SAI (p = 0.006 and p = 0.001), VAI (p < 0.001 and p < 0.001), and SMI (p < 0.001and p = 0.007) were identified as independent correlates of disease activity status (both disease activity and moderate-to-severe activity), with disease activity status independently positively correlated with SAI and SMI and independently negatively correlated with VAI. In determining the disease activity and moderate-to-severe activity status, SMI performed best relative to SAI and VAI, with areas under the ROC curve of 0.865 and 0.801, respectively. SAI (p = 0.015), SMI (p = 0.011) and decreased skeletal muscle mass (p = 0.027) were significantly different between different disease behavior groups (inflammatory disease behavior group, complex disease behavior group) but were not independent correlates (p > 0.05). Body composition parameters of CD patients treated with IFX correlate with the endoscopic disease severity, and SMI can be used as a reliable indicator of disease activity status.

Body Composition as Prognostic Markers for Survival of Patients with Non-Metastatic Non-Small-Cell Lung Cancer

Objective: Lung cancer is the leading cause of cancer-related deaths. Although, previous research have shown that patients with non-small-cell lung cancer (NSCLC), with a higher body mass index (BMI), have a lower risk of death, only a few studies have examined the effects of body composition. Hence, this study examined the prognostic value of skeletal muscle mass and fat mass in patients with non-metastatic NSCLC. Material and Methods: This was a retrospective cohort study; from 2008 to 2012. Eighty-eight of 130 non-metastatic NSCLC patients underwent computed tomography to assess paravertebral skeletal muscle, subcutaneous adipose tissue (SAT), and visceral adipose-tissue (VAT) at the 3rd lumbar vertebral level. Spearman correlation analysis was used to analyze body-composition correlations. Cox regression analysis was used to determine prognostic markers. Results: Higher SAT and VAT indices were associated with a higher-survival probability (HR, 0.79; p-value=0.001 and, HR 0.88; p-value=0.016, respectively). In contrast, higher SAT density and VAT/SAT ratio were associated with a lower survival probability (HR 1.16, p-value=0.012; HR 1.28, p-value=0.006, respectively). Lower performance status and TNM stage 3 were associated with lower-survival probability (HR 2.60; p-value=0.004, HR 1.92; p-value=0.035, respectively).Conclusion: The VAT index predicts a better prognosis for patients with non-metastatic lung cancer; however, visceral-fat distribution, as measured by a high VAT/SAT ratio, is associated with a worse prognosis.

Quantification of needle angles for lumbar medial branch denervation targeting the posterior half of the superior articular process: an osteological study.

Lumbar medial branch radiofrequency ablation (RFA) is a common intervention to manage chronic axial low back pain originating from the facet joints. A more parasagittal approach targeting the posterior half of the lateral neck of superior articular process (SAP) was previously proposed. However, specific needle angles to achieve parallel placement at this target site have not been investigated. To quantify and compare the needle angles, on posterior and lateral views, to achieve parallel placement of electrodes along the medial branch at the posterior half of the lateral neck of SAP at each lumbar vertebral level (L1-L5) and sacrum. Osteological Study. Twelve disarticulated lumbosacral spines (n = 72 individual bones) were used in this study. Needles were placed along the periosteum of the posterior half of the lateral neck of SAP, bilaterally and photographed. Mean needle angles for each vertebral level (L1-L5) and sacrum were quantified, and statistical differences were analyzed. The posterior view provided the degrees of lateral displacement from the parasagittal plane (abduction angle), while the lateral view provided the degrees of declination (cranial-to-caudal angle) of the needle. Mean needle angles at each level varied, ranging from 5.63 ± 5.76° to 14.50 ± 14.24° (abduction angle, posterior view) and 40.17 ± 7.32° to 64.10 ± 9.73° (cranial-to-caudal angle, lateral view). In posterior view, a < 10-degree needle angle interval was most frequently identified (57.0% of needle placements). In lateral view, the 40-50-degree (L1-L2), 50-60-degree (L3-L5), and 60-70-degree (sacrum) needle angle intervals occurred most frequently (54.2%, 50.0%, and 41.7% of needle placements, respectively). Targeting the posterior half of the lateral neck of SAP required <10-degree angulation from parasagittal plane in majority of cases. However, variability of needle angles suggests a standard "one-size-fits-all" approach may not be the optimal technique.

A preliminary study on the effect of renal function on the metabolism of 18F-FDG in the human cerebellum.

The cerebellum is less affected by normal aging or neurodegenerative diseases, the aim of this paper is to investigate the effect of renal function status on uptake of 2-deoxy-2-[18F]fluoro-D-glucose (18F-FDG) in human cerebellum based on independent creatinine (CRE) or blood urea nitrogen (BUN) levels. A total of 253 patients who underwent 18F-FDG PET/CT scans were included. The patients were divided into groups according to renal function status: 201 patients with normal renal function, 16 patients with increase CRE, 36 patients with decrease CRE, and 31 patients with abnormal BUN. The maximum standardized uptake values were obtained in regions of interest (ROIs) for multiple tissue types (right cerebellum, right lobe of liver, right lung, bone marrow and psoas muscle at the level of the fourth lumbar vertebra). Moreover, the selected normal CRE groups were pair-matched with CRE decrease group with respect to age, sex, body mass index and glucose, respectively. Among 253 patients who met the inclusion/exclusion criteria, the final analysis included 967 ROIs (244 cerebellum, 191 lungs, 230 muscles, 145 bone marrow, and 157 liver) from 18F-FDG PET/CT scans. Among patients grouped by CRE or BUN levels, the uptake of 18F-FDG by cerebellum was significantly decreased in patients with CRE decrease level (P=0.001). There were no statistically significant differences between the other groups. Matched-pair analysis indicated there were no significant changes in outcomes between the CRE decrease group and the age-, sex-, BMI-, and glucose-matched controls compared to pre-matching. In patients with normal renal function and reduced CRE concentration, decrease cerebellar glucose metabolism was observed; however, no abnormal uptake of 18F-FDG was found in the cerebellum and other normal tissues of patients with impaired renal function. Consequently, in the study of cerebellar 18F-FDG metabolism, it may be necessary to consider the influence of blood CRE level.

Detection of Sarcopenia in Patients with Liver Cirrhosis Using the Bioelectrical Impedance Analysis.

Bioelectrical impedance analysis (BIA) is a body composition assessment method. We aimed to determine its accuracy in the detection of sarcopenia in patients with liver cirrhosis (LC), using skeletal muscle index (SMI) at the level of third lumbar vertebra (L3-SMI) obtained using multislice computed tomography as the reference method. Patients with LC were enrolled in the period October 2019-March 2022 and follow-ups were conducted until January 2023. Their BIA parameters were compared against L3-SMI, and BIA cut-off values were proposed using AUROC analysis. Patients underwent outcome analysis based on obtained clinical characteristics. A total of 106 patients were included. We found a fair correlation between BIA parameters with the L3-SMI. We determined cut-off values of ≤11.1 kg/m2 for BIA-SMI (Se 73%, Sp 66%, AUROC 0.737, p < 0.001) and ≤5.05° for phase angle (PA) (Se 79%, Sp 60%, AUROC 0.762, p < 0.001) in the detection of sarcopenia. The relative risk of death was 2.2 times higher in patients with skeletal muscle mass (SMM) ≤ 36.5 kg. SMM was significantly associated with outcome in Kaplan-Meier analysis. This non-invasive and simple method that showed fair performances and a very good outcome prediction could provide for the unmet need for fast and affordable detection of sarcopenia in patients with LC and should be further evaluated.

Body composition is associated with disease aetiology and prognosis in patients undergoing resection of intrahepatic cholangiocarcinoma.

Body composition alterations are frequent in patients with cancer or chronic liver disease, but their prognostic value remains unclear in many cancer entities. We investigated the impact of disease aetiology and body composition after surgery for intrahepatic cholangiocarcinoma (iCCA), a rare and understudied cancer entity in European and North American cohorts. Computer tomography-based assessment of body composition at the level of the third lumbar vertebra was performed in 173 patients undergoing curative-intent liver resection for iCCA at the Department of Surgery, Charité - Universitätsmedizin Berlin. Muscle mass and -composition as well as subcutaneous and visceral adipose tissue quantity were determined semi-automatically. (Secondary) sarcopenia, sarcopenic obesity, myosteatosis, visceral and subcutaneous obesity were correlated to clinicopathological data. Sarcopenia was associated with post-operative morbidity (intraoperative transfusions [p = 0.027], Clavien-Dindo ≥ IIIb complications [p = 0.030], post-operative comprehensive complication index, CCI [p < 0.001]). Inferior overall survival was noted in patients with myosteatosis (33 vs. 23 months, p = 0.020). Fifty-eight patients (34%) had metabolic (dysfunction)-associated fatty liver disease (MAFLD) and had a significantly higher incidence of sarcopenic (p = 0.006), visceral (p < 0.001) and subcutaneous obesity (p < 0.001). Patients with MAFLD had longer time-to-recurrence(median: 38 vs. 12 months, p = 0.025, log-rank test). Multivariable cox regression analysis confirmed only clinical, and not body, composition parameters (age > 65, fresh frozen plasma transfusions) as independently prognostic for overall survival. This study evidenced a high prevalence of MAFLD in iCCA, suggesting its potential contribution to disease aetiology. Alterations of muscle mass and adipose tissue were more frequent in patients with MAFLD.

Effects of sarcopenia and myosteatosis are alleviated in reduced port surgery for diverticulitis

PurposeMany studies report the predictive value of sarcopenia, myosteatosis, and visceral fat for clinical outcome after surgery. Radiological analysis of body composition is a valuable tool for identifying high-risk patients undergoing major abdominal surgery. Despite the high prevalence of diverticular disease, patients with benign conditions have hardly been studied in this context. This study aims to evaluate the impact of reduced port surgery on the outcome of patients with diverticulitis, adjusting for body composition.MethodsWe assessed body composition profiles using preoperative CT slices at the level of the third lumbar vertebra in consecutive patients undergoing single-port elective surgery for diverticulitis in a single center. The effects of sarcopenia, myosteatosis, and visceral fat on mortality and complications were analyzed and adjusted for age and gender.ResultsWe enrolled 99 patients with diverticulitis undergoing elective single port surgery in this study. Of the patients, 71.2% had sarcopenia and 60.6% had myosteatosis. The overall complication rate was 17.2%, and the rate of anastomotic leakage was 4.0%. Thirty-day mortality was 2.0%. Loss of skeletal muscle mass, myosteatosis, and visceral fat were not associated with higher complication or mortality rates in our cohort.ConclusionBody composition profiles had no impact on the clinical course in our cohort. Minimally invasive surgery may potentially compensate for the adverse effects of sarcopenia and myosteatosis in diverticulitis.

Intramuscular and abdominal fat measured by computed tomography and mortality of hemodialysis patients.

In hemodialysis patients, high body mass index is associated with low mortality while abdominal obesity relates to increased mortality. We aimed to investigate the association between muscle mass, intramuscular fat and abdominal fat measured by abdominal computed tomography (CT), and mortality in this patients population. This two-center retrospective cohort study included hemodialysis patients who underwent abdominal CT between January 2013 and December 2018. Skeletal muscle mass index (SMI), muscle radiation attenuation (MRA) as an index of intramuscular fat, and visceral fat to subcutaneous fat ratio (VSR) were calculated using CT images at the third lumbar vertebral level. Multivariate Cox proportional hazards model was used to determine the independent predictors of all-cause, cardiovascular and non-cardiovascular mortalities. The study included 344 patients (median age 71.0 years; female 33.7%), among whom 145 died during a median follow-up of 4.9 years-46 and 99 from cardiovascular and non-cardiovascular causes, respectively. Lower MRA [hazard ratio (HR) 0.71, 95% confidence interval (CI) 0.58-0.87, P=.001] and higher VSR (HR 1.17, 95% CI 1.01-1.37, P=.04) were independently associated with higher all-cause mortality but not with lower SMI (HR 0.87, 95% CI 0.68-1.11, P=.26). Lower MRA (HR 0.51, 95% CI 0.35-0.73, P<.001) and higher VSR (HR 1.29, 95% CI 1.09-1.54, P=.003) were also associated with cardiovascular and non-cardiovascular mortality, respectively. Intramuscular fat and abdominal fat as measured using abdominal CT in hemodialysis patients are stronger independent predictors of mortality than muscle mass.

Assessment of longitudinal changes in body composition of children with lymphoma and rhabdomyosarcoma.

Studies examining changes in skeletal muscle and adipose tissue during treatment for cancer in children, adolescents, and young adults and their effect on the risk of chemotherapy toxicity (chemotoxicity) are limited. Among 78 patients with lymphoma (79.5%) and rhabdomyosarcoma (20.5%), changes were measured in skeletal muscle (skeletal muscle index [SMI]; skeletal muscle density [SMD]) and adipose tissue (height-adjusted total adipose tissue [hTAT]) between baseline and first subsequent computed tomography scans at the third lumbar vertebral level by using commercially available software. Body mass index (BMI; operationalized as a percentile [BMI%ile]) and body surface area (BSA) were examined at each time point. The association of changes in body composition with chemotoxicities was examined by using linear regression. The median age at cancer diagnosis of this cohort (62.8% male; 55.1% non-Hispanic White) was 12.7 years (2.5-21.1 years). The median time between scans was 48days (range, 8-207 days). By adjusting for demographics and disease characteristics, this study found that patients undergo a significant decline in SMD (β ± standard error [SE]=-4.1±1.4; p<.01). No significant changes in SMI (β ± SE=-0.5±1.0; p=.7), hTAT (β ± SE=5.5±3.9; p=.2), BMI% (β ± SE=4.1±4.8; p=.3), or BSA (β ± SE=-0.02±0.01; p=.3) were observed. Decline in SMD (per Hounsfield unit) was associated with a greater proportion of chemotherapy cycles with grade ≥3 nonhematologic toxicity (β ± SE=1.09±0.51; p=.04). This study shows that children, adolescents, and young adults with lymphoma and rhabdomyosarcoma undergo a decline in SMD early during treatment, which is associated with a risk of chemotoxicities. Future studies should focus on interventions designed at preventing the loss of muscle during treatment. We show that among children, adolescents, and young adults with lymphoma and rhabdomyosarcoma receiving chemotherapy, skeletal muscle density declines early during treatment. Additionally, a decline in skeletal muscle density is associated with a greater risk of nonhematologic chemotoxicities.

Preoperative CT-Based Skeletal Muscle Mass Depletion and Outcomes after Total Laryngectomy.

To assess the role of preoperative CT-based skeletal muscle mass depletion on postoperative clinical outcomes and survival in patients who underwent total laryngectomy for cancer. Patients operated on between January 2011 and March 2020 were retrospectively included. Skeletal muscle area and intra- and inter-muscular fat accumulation were measured at the third lumbar vertebral level on preoperative CT scans. Skeletal muscle mass depletion was defined based on pre-established cut-off values. Their association with postoperative morbidity, length of stay (LOS), costs, and survival was assessed. A total of 84 patients were included, of which 37 (44%) had preoperative skeletal muscle mass depletion. The rate of postoperative fistula (23% vs. 35%, p = 0.348), cutaneous cervical dehiscence (17% vs. 11%, p = 0.629), superficial incisional surgical site infections (SSI) (12% vs. 10%, p = 1.000), and unplanned reoperation (38% vs. 37%, p = 1.000) were comparable between the two patient groups. No difference in median LOS was observed (41 vs. 33 days, p = 0.295), nor in treatment costs (119,976 vs. 109,402 CHF, p = 0.585). The median overall survival was comparable between the two groups (3.43 vs. 4.95 years, p = 0.09). Skeletal muscle mass depletion alone had no significant impact on postoperative clinical outcomes or survival.

Association of Visceral Fat Obesity, Sarcopenia, and Myosteatosis with Non-Alcoholic Fatty Liver Disease without Obesity.

To investigate whether non-alcoholic fatty liver disease (NAFLD) in individuals without generalized obesity is associated with visceral fat obesity (VFO), sarcopenia, and/or myosteatosis. This cross-sectional analysis included 14,400 individuals (7,470 men) who underwent abdominal computed tomography scans during routine health examinations. The total abdominal muscle area (TAMA) and skeletal muscle area (SMA) at the 3rd lumbar vertebral level were measured. The SMA was divided into the normal attenuation muscle area (NAMA) and low attenuation muscle area, and the NAMA/TAMA index was calculated. VFO was defined by visceral to subcutaneous fat ratio, sarcopenia by body mass index-adjusted SMA, and myosteatosis by the NAMA/TAMA index. NAFLD was diagnosed with ultrasonography. Of the 14,400 individuals, 4,748 (33.0%) had NAFLD, and the prevalence of NAFLD among non-obese individuals was 21.4%. In regression analysis, both sarcopenia (men: odds ratio [OR] 1.41, 95% confidence interval [CI] 1.19-1.67, P<0.001; women: OR=1.59, 95% CI 1.40-1.90, P<0.001) and myosteatosis (men: OR=1.24, 95% CI 1.02-1.50, P=0,028; women: OR=1.23, 95% CI 1.04-1.46, P=0.017) were significantly associated with non-obese NAFLD after considering for VFO and other various risk factors, whereas VFO (men: OR=3.97, 95% CI 3.43-4.59 [adjusted for sarcopenia], OR 3.98, 95% CI 3.44-4.60 [adjusted for myosteatosis]; women: OR=5.42, 95% CI 4.53-6.42 [adjusted for sarcopenia], OR=5.33, 95% CI 4.51-6.31 [adjusted for myosteatosis]; all P<0.001) was strongly associated with non-obese NAFLD after adjustment with various known risk factors. In addition to VFO, sarcopenia and/or myosteatosis were significantly associated with non-obese NAFLD.

Body composition predicts prognosis of hepatocellular carcinoma patients undergoing immune checkpoint inhibitors.

Immune checkpoint inhibitors (ICIs) with anti-PD-1/PD-L1 antibody are promising treatments for hepatocellular carcinoma (HCC), but lack reliable biomarkers of response. In the present study, we aimed to investigate the correlation between pre-treatment body composition measures (muscle, adipose, etc.) and the prognosis of patients with HCC treated with ICIs. We measured the total area of all skeletal muscles, total adipose tissue area, subcutaneous adipose tissue area, and visceral adipose tissue area at the level of the third lumbar vertebra using quantitative CT. Then, we calculated the skeletal muscle index, visceral adipose tissue index, subcutaneous adipose tissue index (SATI), and total adipose tissue index. The Cox regression model was used to determine the independent factors of the patient prognosis and construct a nomogram to predict survival. The consistency index (C-index) and calibration curve were used to determine the predictive accuracy and discrimination ability of the nomogram. Multivariate analysis revealed that the SATI (high- vs. low SATI; HR 0.251; 95% CI 0.109-0.577; P = 0.001), sarcopenia (sarcopenia vs. no sarcopenia; HR 2.171; 95% CI 1.100-4.284; P = 0.026), and portal vein tumor thrombus (PVTT) (PVTT vs. No PVTT; HR 2.429; 95% CI 1. 197-4. 929; P = 0.014) were indicated as independent prognostic factors for OS in multivariate analysis. Multivariate analysis indicated that Child-Pugh class (HR 0.477, 95% CI 0.257-0.885, P = 0.019) and sarcopenia (HR 2.376, 95% CI 1.335-4.230, P = 0.003) were independent prognostic factors of PFS. We established a nomogram using SATI, SA, and PVTT to predict the 12-month and 18-month survival probability of HCC patients treated with ICIs. The C-index of the nomogram was 0.754 (95% CI 0.686-0.823), and the calibration curve confirmed that the predicted results were in good agreement with the actual observations. Subcutaneous adipose and sarcopenia are significant prognostic factors of patients with HCC receiving ICIs. A nomogram based on body composition parameters and clinical factors could well predict survival in HCC patients treated with ICIs.

Association between computed tomography-assessed sarcopenia and mortality in patients with anti-neutrophil cytoplasmic antibody-associated vasculitis.

Sarcopenia is frequently observed in patients with autoimmune rheumatic diseases; however, its relationship with patient outcomes has not been well understood. This study evaluated the influence of sarcopenia, especially muscle quality, on outcomes of antineutrophil cytoplasmic antibody-associated vasculitis (AAV). Records of patients with AAV at the Severance Hospital with computed tomography (CT) images taken at initial disease diagnosis were retrospectively reviewed. For measures of sarcopenia, normal attenuation muscle area (NAMA), low attenuation muscle area (LAMA), intramuscular adipose tissue (IMAT), and total abdominal muscle area (TAMA) in the axial muscles of the middle third lumbar vertebra level were calculated. Correlations between NAMA, LAMA, IMAT, and baseline patient characteristics, as well as the association between the NAMA/TAMA ratio and clinical outcomes were assessed. A total of 136 patients with CT images at AAV diagnosis were identified. Correlation analyses revealed that age, female sex, total cholesterol, and alanine aminotransferase were significantly associated with NAMA. LAMA was associated with age, body mass index (BMI), five-factor score (FFS), and C-reactive protein, and a relationship between IMAT and age and BMI was observed. During the follow up of 31.2 months, 23 (16.9%) patients died, and Cox-proportional hazard analysis demonstrated that a NAMA/TAMA ≤0.46 (odds ratio [OR] 10.247, p < .001), female sex (OR 0.206, p = .006), dyslipidemia (OR 3.143, p = .027), creatinine (OR 1.342, p = .012), and FFS (OR 1.775, p = .046), were independently associated with patient mortality. A higher rate of mortality was observed in patients with AAV with NAMA/TAMA ≤0.46, indicating that careful monitoring is required in these patients.

Application of creatinine height index in patients with trauma for the evaluation of psoas muscle mass: A clinical validation study.

The creatinine height index (CHI) is an estimate of lean body mass. We hypothesize that a modified CHI estimate using serum creatinine (sCr) levels in patients with normal renal function when performed soon after injury would reflect preinjury protein nutrition status. The urine CHI (uCHI) was calculated using the 24-h urine sample. The serum-derived estimated CHI (sCHI) was calculated using the sCr on admission. Correlation between abdominal computed tomographyimages at specific lumbar vertebral levels and total body fat and muscle content was used for comparison as an independent measurement of nutrition status unlikely to be substantially altered by trauma. A total of 45 patients were enrolled, all with a significant injury burden (median injury severity score [ISS] = 25; interquartile range, 17-35). The calculated sCHI on admission was 71.0% (SD = 26.9%) and likely underestimates the CHI when compared with uCHI (mean = 112.5%, SD = 32.6%). Stratifying by degree of stress demonstrated that in a group of 23 moderately and severely stressed patients, uCHI (mean = 112.7%, SD = 5.7%) and sCHI (mean = 60.8%, SD = 1.9%) were significantly different and without correlation (r = -0.26, P = 0.91). In patients without stress, there was a significant negative correlation between sCHI and psoas muscle area (r = -0.869, P = 0.03), and in patients with severe stress there was a significant positive correlation between uCHI and psoas muscle area (r = 0.733, P = 0.016). The CHI calculated from the initial sCr is not an appropriate estimate of uCHI in critically ill trauma patients and is not a valid measure of psoas muscle mass in this setting.

#3947 COMPARISON OF CT SCAN AND BIOIMPEDANCE SPECTROSCOPY FOR FAT FREE MASS MEASUREMENTS IN PATIENTS WITH CHRONIC KIDNEY DISEASE

Abstract Background and Aims Malnutrition and sarcopenia are highly prevalent in patients with chronic kidney disease (CKD). Since body mass index and body weight do not reflect body composition, measuring fat free mass (FFM) is essential. Bio-impedance spectroscopy (BIS) is frequently used for monitoring body composition in patients with CKD. Unfortunately, BIS derived lean tissue mass (LTMBIS) is not suitable for comparison with the Global Leadership Initiative on Malnutrition (GLIM) cut-off values for the diagnosis of malnutrition, or for calculating dietary protein requirements. Hypothetically, FFM could be derived from BIS data (FFMBIS). This study aims to compare FFMBIS and LTMBIS with computed tomography (CT) scan derived FFM (FFMCT). Secondarily, we aimed to explore the impact of using different methods on calculated daily protein requirements. Method CT scans of 60 patients with CKD stage 4-5 were analyzed at third lumbar vertebra (L3) level for muscle cross-sectional area, which was converted to FFMCT. Spearman rank correlation coefficient and 95% limits of agreement (LoA) were calculated to compare FFMBIS and LTMBIS with FFMCT. Dietary protein requirements were determined based on FFMCT, FFMBIS, and adjusted body weight. Deviations over 10% from FFMCT were considered clinically relevant. Results FFMCT correlated strongest with FFMBIS (r=0.78, p&amp;lt;0.001), in males (r=0.72, p&amp;lt;0.001), and in females (r=0.60, p&amp;lt;0.001). A mean difference of -0.54 kg was found between FFMBIS and FFMCT (LoA: -14.88 to 13.7 kg, p=0.544). Between LTMBIS and FFMCT a mean difference of -12.2 kg was apparent (LoA: -28.7 to 4.2 kg, p&amp;lt;0.001). Compared with FFMCT, the highest occurrence of accurate predicted protein requirements was found for FFMBIS. Mean difference between protein requirements according to FFMBIS and FFMCT was -0.7 ± 9.9 grams in males and -0.9 ± 10.9 grams in females. Conclusion FFMBIS seems a valid surrogate measure for the estimation of FFM as compared to FFMCT. As expected, large clinically relevant differences were observed in calculated protein requirements when comparing multiple methods, with FFMBIS having the best accuracy compared to FFMCT.