Comparison of Anthropometry, Bioelectrical Impedance, and Dual-energy X-ray Absorptiometry for Body Composition in Cirrhosis

Abstract

Background & aims: This study was planned to evaluate triceps skinfold thickness (TSFT), mid-arm muscle circumference (MAMC) and bioelectrical impedance analysis (BIA) for assessing body composition using dual-energy X-ray absorptiometry (DEXA) (reference) and to predict fat mass (FM) and fat-free mass (FFM) in patients with cirrhosis.

Methods: FM and FFM were assessed by using DEXA and BIA. Skin-fold calliper was used for measuring TSFT, and MAMC was calculated. Bland-Altman plot was used to determine agreement and linear regression analysis for obtaining equations to predict FM and FFM.

Results: Patients with cirrhosis (n = 302, 241 male, age 43.7 ± 12.0 years) were included. Bland-Altman plot showed very good agreement between BIA and DEXA for the estimation of FM and FFM. Majority of patients were within the limit of agreement: FM (98%) and FFM (96.4%). BIA shows a positive correlation with DEXA:FM (r = 0.73, P ≤ 0.001) and FFM (r = 0.86, P ≤ 0.001). DEXA (FM and FFM) shows a positive correlation with TSFT (r = 0.69, P ≤ 0.01) and MAMC (r = 0.61, P ≤ 0.01). The mean difference between the observed and predicted value of FM and FFM by BIA in the developmental set was 0.01 and 0.05, respectively; whereas in the validation set, it was -0.13 and 0.86, respectively. The mean difference between the observed and predicted value of TSFT and MAMC in the developmental set was 0.43 and 0.07; whereas, in the validation set, it was 0.16 and 0.48, respectively.

Conclusion: Anthropometry (TSFT and MAMC) and BIA are simple and easy to use and can be a substitute of DEXA for FM and FFM assessment in routine clinical settings in patients with cirrhosis.

Keywords: ALP, alkaline phosphatise; ALT, alanine aminotransferase; ANA, anti-nuclear antibody; ASMA, anti-smooth muscle antibody; AST, aspartate aminotransferase; BIA, bioelectrical impedance analysis; BMC, bone mineral content; BMI, body mass index; CTP, Child–Turcotte–Pugh score; DEXA, dual-energy X-ray absorptiometry; FFM, fat-free mass; FM, fat mass; HBsAg, hepatitis B surface antigen; MAMC, mid-arm muscle circumference; TSFT, triceps skinfold thickness; anthropometric measurements; anti-HCV, anti-hepatitis C virus; anti-LKM1, anti-liver kidney microsomal antibody type 1; bioelectrical impedance analysis; cirrhosis; dual-energy X-ray absorptiometry; nutritional assessment.

Figure 1

Bland–Altman plot showing the limit of agreement between bioelectrical impedance analysis (BIA) and dual-energy X-ray absorptiometry (DEXA) for the assessment of fat mass (A) and fat-free mass (B) in the patients with cirrhosis (n = 297). Scatter plot of fat mass (C) and fat-free mass (D) measured using DEXA (kg) and BIA (kg).

Figure 2

Scatter plot of fat mass (A) measured using dual-energy X-ray absorptiometry (DEXA [kg]) and triceps skinfold thickness (TSFT [cm]); and scatter plot of fat-free mass (B) measured using DEXA (kg) and mid-arm muscle circumference (MAMC [cm]) (n = 297).

Supplementary Figure 1

Consort flow chart.