Using Bioimpedance Spectroscopy for Diagnosis of Malnutrition in Chronic Kidney Disease Stage 5—Is It Useful?

Abstract

Objective: Malnutrition is common in chronic kidney disease stage 5 (CKD5) and has negative clinical impacts. The aim of the present study is to evaluate bioimpedance spectroscopy (BIS) in diagnosing malnutrition in CKD5 including hemodialysis and peritoneal dialysis patients (CKD5D) using cutoff values for fat-free mass index (FFMI) according to the Global Leadership Initiative on Malnutrition criteria. Dual-energy X-ray absorptiometry (DXA) was used as a reference method.Design and Methods: We performed a single-center cross-sectional diagnostic study of 90 patients with CKD5 or CKD5D.Results: BIS-derived FFMI estimates were significantly higher compared with those obtained by DXA (18.5 6 2.6 vs.17.8 6 2.0, P , .05). The mean difference in FFMI estimates between the methods (DXA-BIS) and Bland-Altman 95% limits of agreements is -0.38 (2.76, -3.52) kg/m 2 . Overhydration (B 5 0.67, P , .001), age (B 5 0.02, P 5 .037), and interactions between overhydration and CKD5 subgroups (P 5 .034) independently predicted bias in BIS-derived FFMI. BIS-derived FFMI showed poor sensitivity (64%) and positive predictive value (48%) in diagnosing malnutrition in the present study population.Conclusion: The present study showed a limited agreement between estimates of FFMI derived by BIS and DXA due to a large interindividual variation. Using BIS as a clinical tool for assessing FFMI has limited accuracy and poor sensitivity in diagnosing malnutrition in patients with CKD5 and CKD5D.

Application of Bioelectrical Impedance Analysis in Nutritional Management of Patients with Chronic Kidney Disease

“…The results showed that BIA equations based on healthy people may not be applicable to dialysis patients, especially PD patients [ 17 ]. One cross-sectional study involving both pre-dialysis CKD5 patients and dialysis patients suggested poor agreement between fat-free mass index (FFMI) measured by BIA and that measured by DEXA [ 18 ]. The above results suggest that specific BIA equations should be established for different types of CKD patients including non-dialysis and kidney transplant patients to obtain the most accurate results [ 15 ].…”

Nutritional Assessments by Bioimpedance Technique in Dialysis Patients

“…Most of the studies demonstrated strong correlations (r > 0.7) between the parameters derived from bioimpedance techniques and those from DEXA in both PD and HD patients [ 48 , 49 , 50 , 51 , 52 , 53 ]. Konings et al were one of the first who compared the body composition parameters measured by MF-BIA and DEXA in 40 Caucasian PD patients [ 48 ].…”

“…But it should be noted that the mean BMI of this cohort was 22 kg/m 2 , and it remained uncertain whether the accuracy of skinfold thickness can be maintained in obese patients (whose bony prominence is obscured). Other studies using DEXA as reference method reported no significant difference compared with skinfold thickness and BIA/BIS, albeit with a variable limit of agreement [ 53 , 55 ]. Notably, Bross et al showed that SF-BIA with the Kushur equation had the lowest prediction error in estimating the percentage of body fat in 118 HD patients, thereby indicating the performance between the prediction equations were not identical [ 55 ].…”

“…Both the LTI and FTI were not associated with E/e’ or LAVi, thus suggesting the bioimpedance-derived nutrition indexes were not biased by volume overload [ 57 ]. When using BIS-derived hydration parameters, the difference in the FFM estimated by DEXA versus the bioimpedance technique were shown to correlate with the OH in some studies [ 49 , 53 ] but not others [ 50 ], and this effect was apparently more obvious in PD patents [ 53 ]. It is, however, crucial to realize that FFM measurement by DEXA itself is also influenced by hydration status [ 59 ].…”

Global Kidney Nutrition Care and Health Literacy: Overcoming the Disparities in Renal Nutrition Service Capacity and Education

“…These patientreported outcomes are signals that conditions will worsen if left unchecked. Eyre et al 27 critique the use of multifrequency bioimpedance spectroscopy in late-stage CKD for body composition assessment using whole-body dual-energy x-ray absorptiometry as standard. Their work identified that bioimpedance was only moderately accurate for estimating the fat-free mass index.…”