Muscle mass evaluation using psoas muscle mass index by computed tomography imaging in hemodialysis patients

• Published in: Clinical nutrition ESPEN Vol. 44; pp. 410 - 414
• Main Authors: Ito, Kiyonori, Ookawara, Susumu, Imai, Sojiro, Kakuda, Hideo, Bandai, Yusaku, Fueki, Mariko, Yasuda, Masatoshi, Kamimura, Tatsuya, Kiryu, Satoshi, Wada, Noriko, Hamashima, Yuri, Shindo, Mitsutoshi, Kobayashi, Tadanao, Sanayama, Hidenori, Kaku, Yoshio, Tanno, Keisuke, Ohnishi, Yasushi, Iino, Noriaki, Dezaki, Katsuya, Kakei, Masafumi, Tabei, Kaoru, Morishita, Yoshiyuki
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.08.2021
• Subjects: Computed tomography; Hemodialysis; Psoas muscle mass index; Sarcopenia; Skeletal muscle mass index; Sarcopenia; Psoas muscle mass index; Skeletal muscle mass index; Computed tomography; Hemodialysis
• ISSN: 2405-4577; 2405-4577
• DOI: 10.1016/j.clnesp.2021.04.029

The use of the psoas muscle mass index (PMI) using computed tomography (CT) has become a marker of interest to evaluate whole body muscle mass. However, in hemodialysis (HD) patients, reports about the clinical significance of psoas muscle evaluation are limited. We aimed to clarify the association between PMI and skeletal muscle mass index (SMI) using bioelectrical impedance analysis (BIA), and to investigate factors affecting PMI in HD patients. In this prospective observational study, to evaluate muscle mass, SMI was measured using BIA after HD, and PMI was measured by the manual trace method on routinely available CT scans. PMI measurement was assessed twice by two physicians to compute intra-rater and inter-rater reliability. The correlations between PMI and the clinical factors were evaluated using Pearson's correlation coefficient and a linear regression analysis. Variables with a p-value < 0.05 in the simple linear regression analysis were included in the multivariable linear regression analysis to identify the factors that affected PMI of the HD patients. Fifty HD patients were recruited (31 males and 19 females; HD duration, 9.0 ± 8.8 years). The SMI was 6.10 ± 1.20 kg/m2, and the PMI was 4.79 ± 1.61 cm2/m2. Regarding the reliability of PMI measurements, intra-rater reliability [intra-class correlation (ICC) = 0.999] and inter-rater reliability (ICC = 0.998) were high in this study. The mean PMI of male patients was 5.40 ± 1.62 cm2/m2, while that of female patients was significantly lower (3.78 ± 0.98 cm2/m2; p < 0.001). The PMI was significantly and positively correlated with SMI (r = 0.630, p < 0.001), in addition to HD duration, body mass index (BMI), serum phosphate and serum creatinine (Cr). In the multivariate linear regression analysis by two models using SMI or BMI, they were respectively extracted as an independent factor associating with PMI, in addition to serum Cr and the difference of sex. PMI assessed with CT positively correlated with SMI measured using BIA. PMI might be one of the methods for evaluating the muscle mass in HD patients, when CT scans are taken as part of routine care. •Sarcopenia is associated with poor prognosis in HD patients and needs to be evaluated.•PMI using CT imaging is a recent evaluation method for muscle mass in HD patients.•PMI was positively correlated with SMI.•Factors affecting PMI in HD patients were sex, serum Cr, and BMI or SMI.•PMI might be one of the useful methods to evaluate muscle mass in HD patients.