TY - JOUR

T1 - Calibration of bioelectrical impedance analysis against deuterium dilution for body composition assessment in stunted Ugandan children

AU - Lewis, Jack Ivor

AU - Friis, Henrik

AU - Mupere, Ezekiel

AU - Wells, Jonathan C

AU - Grenov, Benedikte

N1 - CURIS 2023 NEXS 024

PY - 2023

Y1 - 2023

N2 - Background: BIA represents an important tool in body composition (BC) assessment, especially in low-income settings in which simple and affordable options are preferred. There is a particular need to measure BC in stunted children, in which cases population-specific BIA estimating equations are lacking.Objective: We calibrated an equation to estimate body composition from BIA using deuterium dilution (2H) as the criterion method in stunted children.Methods: We measured BC with 2H and performed BIA in stunted Ugandan children (n = 50). Multiple linear regression models were constructed to predict 2H-derived FFM from BIA-derived whole-body impedance and other relevant predictors. Model performance was expressed as adjusted R2 and RMSE. Prediction errors were also calculated.Results: Participants were aged 16-59 mo, at whom 46% were girls, and their median [IQR] height-for-age z-score (HAZ) was -2.58 [-2.92, -2.37] according to WHO growth standards. Impedance index (height2/impendance measured  at 50 kHz) alone explained 89.2% variation in FFM and had an RMSE of 583 g (precision error 6.5%). The final model contained age, sex, impedance index and height-for-age z-score as predictors, and explained 94.5% variation in FFM with an RMSE of 402 g (precision error 4.5%).Conclusion: We present a BIA calibration equation for a group of stunted children with relatively low prediction error. This may help evaluate the efficacy of "nutritional supplementation in large-scale trials in the same population". J Nutr 20xx;xxx:xx.

AB - Background: BIA represents an important tool in body composition (BC) assessment, especially in low-income settings in which simple and affordable options are preferred. There is a particular need to measure BC in stunted children, in which cases population-specific BIA estimating equations are lacking.Objective: We calibrated an equation to estimate body composition from BIA using deuterium dilution (2H) as the criterion method in stunted children.Methods: We measured BC with 2H and performed BIA in stunted Ugandan children (n = 50). Multiple linear regression models were constructed to predict 2H-derived FFM from BIA-derived whole-body impedance and other relevant predictors. Model performance was expressed as adjusted R2 and RMSE. Prediction errors were also calculated.Results: Participants were aged 16-59 mo, at whom 46% were girls, and their median [IQR] height-for-age z-score (HAZ) was -2.58 [-2.92, -2.37] according to WHO growth standards. Impedance index (height2/impendance measured  at 50 kHz) alone explained 89.2% variation in FFM and had an RMSE of 583 g (precision error 6.5%). The final model contained age, sex, impedance index and height-for-age z-score as predictors, and explained 94.5% variation in FFM with an RMSE of 402 g (precision error 4.5%).Conclusion: We present a BIA calibration equation for a group of stunted children with relatively low prediction error. This may help evaluate the efficacy of "nutritional supplementation in large-scale trials in the same population". J Nutr 20xx;xxx:xx.

KW - Faculty of Science

KW - Stunting

KW - Body composition

KW - Deuterium dilution

KW - Bioelectrical impedance analysis

KW - Fat-free mass

KW - Total body water

U2 - 10.1016/j.tjnut.2022.12.028

DO - 10.1016/j.tjnut.2022.12.028

M3 - Journal article

C2 - 36894235

VL - 153

SP - 426

EP - 434

JO - Journal of Nutrition

JF - Journal of Nutrition

SN - 0022-3166

IS - 2

ER -