Identifying critically ill patients with low muscle mass: Agreement between bioelectrical impedance analysis and computed tomography.

Low muscle mass and -quality on ICU admission, as assessed by muscle area and -density on CT-scanning at lumbar level 3 (L3), are associated with increased mortality. However, CT-scan analysis is not feasible for standard care. Bioelectrical impedance analysis (BIA) assesses body composition by incorporating the raw measurements resistance, reactance, and phase angle in equations. Our purpose was to compare BIA- and CT-derived muscle mass, to determine whether BIA identified the patients with low skeletal muscle area on CT-scan, and to determine the relation between raw BIA and raw CT measurements. This prospective observational study included adult intensive care patients with an abdominal CT-scan. CT-scans were analysed at L3 level for skeletal muscle area (cm2) and skeletal muscle density (Hounsfield Units). Muscle area was converted to muscle mass (kg) using the Shen equation (MMCT). BIA was performed within 72 h of the CT-scan. BIA-derived muscle mass was calculated by three equations: Talluri (MMTalluri), Janssen (MMJanssen), and Kyle (MMKyle). To compare BIA- and CT-derived muscle mass correlations, bias, and limits of agreement were calculated. To test whether BIA identifies low skeletal muscle area on CT-scan, ROC-curves were constructed. Furthermore, raw BIA and CT measurements, were correlated and raw CT-measurements were compared between groups with normal and low phase angle. 110 patients were included. Mean age 59 ± 17 years, mean APACHE II score 17 (11-25); 68% male. MMTalluri and MMJanssen were significantly higher (36.0 ± 9.9 kg and 31.5 ± 7.8 kg, respectively) and MMKyle significantly lower (25.2 ± 5.6 kg) than MMCT (29.2 ± 6.7 kg). For all BIA-derived muscle mass equations, a proportional bias was apparent with increasing disagreement at higher muscle mass. MMTalluri correlated strongest with CT-derived muscle mass (r = 0.834, p < 0.001) and had good discriminative capacity to identify patients with low skeletal muscle area on CT-scan (AUC: 0.919 for males; 0.912 for females). Of the raw measurements, phase angle and skeletal muscle density correlated best (r = 0.701, p < 0.001). CT-derived skeletal muscle area and -density were significantly lower in patients with low compared to normal phase angle. Although correlated, absolute values of BIA- and CT-derived muscle mass disagree, especially in the high muscle mass range. However, BIA and CT identified the same critically ill population with low skeletal muscle area on CT-scan. Furthermore, low phase angle corresponded to low skeletal muscle area and -density. ClinicalTrials.gov (NCT02555670).

Looijaard WGPM ，Stapel SN ，Dekker IM ，Rusticus H ，Remmelzwaal S ，Girbes ARJ ，Weijs PJM ，Oudemans-van Straaten HM ... -  《-》

Comparative assessment of skeletal muscle mass using computerized tomography and bioelectrical impedance analysis in critically ill patients.

We compared the evaluation of skeletal muscle mass (SMM) using the computed tomography (CT) and bioelectrical impedance analysis (BIA) methods in critically ill patients. We also evaluated whether BIA can be applied for measuring SM with high accuracy to critically ill patients. We included 135 critically ill surgical patients (83 men and 52 women, mean age: 59.3 years) who got the BIA and abdominal CT scan both within 7 days during the intensive care unit (ICU) stay. With CT scan, skeletal muscle area (SMA) measured from the L3 spine level image was used for calculation of the whole body skeletal muscle volume and mass (kg). Body composition data from BIA were obtained using touch-type electrodes and 50 kHz current. Subgroup analyses for SMM were performed according to the sex, SMA, and edema status of the patients with Pearson correlation or regression analysis et al. SMM from CT and BIA showed a good correlation (p < 0.0001) to sex, SMA, and edema in the subgroup analysis. A stronger correlation was noted between SMM from CT and BIA in male patients or mild edema group than for the other groups. SMM from BIA showed greater values than that from CT (mean difference, 3.35 kg) in all groups, except the normal SMA (higher than 170 cm2 in men, and 110 cm2 in women) group. Male patients and mild edema group showed more SMM as evaluated by BIA when compared to the other groups. SMM measure by BIA in critically ill patients showed high correlation with SMM calculation by CT scan and had greater values than SMM from CT scan. Ajou University Hospital Institutional Review Board DEV-DE4-15-115, Registered Jan 1 2015.

Kim D ，Sun JS ，Lee YH ，Lee JH ，Hong J ，Lee JM ... -  《-》

Comparison of bioelectrical impedance analysis and computed tomography for the assessment of muscle mass in patients with gastric cancer.

Low muscle mass was significantly correlated with poor clinical outcomes in cancer patients. This study aimed to compare the differences between bioelectrical impedance analysis (BIA) and computed tomography (CT) in measuring skeletal muscle mass and detecting low muscle mass in patients with gastric cancer (GC). This cross-sectional study included a total of 302 consecutive patients diagnosed with GC at our institution from October 2021 to March 2023. CT images were analyzed at the L3 level to obtain the cross-sectional area of skeletal muscle, which was subsequently used for calculating whole-body skeletal muscle mass via the Shen equation and skeletal muscle tissue density. BIA was utilized to measure skeletal muscle mass using the manufacturer's proprietary algorithms. Skeletal muscle mass (kg) was divided by height squared (m2) to obtain skeletal muscle index (SMI, kg/m2). Pearson's correlation coefficient was performed to assess the correlation between SMI measured by BIA and CT. The agreement between the two methods was assessed using Bland-Altman analyses. The clinically acceptable agreement was defined as the 95% limits of agreement (LOA) for the percentage bias falling within ± 10%. The area under the receiver operating characteristic curve (AUC) was used to evaluate the performance of BIA in identifying low muscle mass. A total of 59 patients (19.5%) were identified as having low muscle mass based on CT analysis, whereas only 19 patients (6.3%) met the criteria for low muscle mass according to BIA analysis. BIA-measured SMI showed a strong positive correlation with CT-measured SMI in all patients (r = 0.715, P < 0.001). With Bland-Altman analysis, there was a significant mean bias of 1.18 ± 0.96 kg/m2 (95% CI 1.07-1.29, P < 0.001) between SMI measured by BIA and CT. The 95% LOA for the percentage bias ranged from -7.98 to 33.92%, which exceeded the clinically acceptable range of ± 10%. A significant difference was observed in the mean bias of SMI measured by BIA and CT between patients with and without GLIM malnutrition (1.42 ± 0.91 kg/m2 versus 0.98 ± 0.96 kg/m2, P < 0.001). The cut-off values for BIA-measured SMI in identifying low muscle mass using CT as the reference were 10.11 kg/m2 for males and 8.71 kg/m2 for females (male: AUC = 0.840, 95% CI: 0.772-0.908; female: AUC = 0.721, 95% CI: 0.598-0.843). Despite a significant correlation, the values of skeletal muscle mass obtained BIA and CT cannot be used interchangeably. The BIA method may overestimate skeletal muscle mass in GC patients compared to CT, especially among those with GLIM malnutrition, leading to an underestimation of low muscle mass prevalence.

Zuo J ，Zhou D ，Zhang L ，Zhou X ，Gao X ，Hou W ，Wang C ，Jiang P ，Wang X ... -  《-》

Evaluation of Muscle Mass and Malnutrition in Patients with Colorectal Cancer Using the Global Leadership Initiative on Malnutrition Criteria and Comparing Bioelectrical Impedance Analysis and Computed Tomography Measurements.

de Luis Roman D ，López Gómez JJ ，Muñoz M ，Primo D ，Izaola O ，Sánchez I ... -  《Nutrients》

Evaluation of Bioelectrical Impedance Analysis in Critically Ill Patients: Results of a Multicenter Prospective Study.

Kuchnia A ，Earthman C ，Teigen L ，Cole A ，Mourtzakis M ，Paris M ，Looijaard W ，Weijs P ，Oudemans-van Straaten H ，Beilman G ，Day A ，Leung R ，Compher C ，Dhaliwal R ，Peterson S ，Roosevelt H ，Heyland DK ... -  《-》