Body composition in prepubertal, HIV-infected children: a comparison of bioelectrical impedance analysis and dual-energy X-ray absorptiometry

Health-Related Physical Fitness Evaluation in HIV-Diagnosed Children and Adolescents: A Scoping Review

BACKGROUND

Health-related physical fitness has been widely used to investigate the adverse effects of HIV infection/ART in children and adolescents. However, methods/protocols and cut-points applied for investigating health-related physical fitness are not clear. The aim of this scoping review was to map the literature to identify gaps in knowledge regarding the methods/protocols and cut-points.

METHODS

A scoping review, following the Joana Briggs Institute (JBI) guidelines, was conducted through ten major databases. Search followed the PCC strategy to construct block of terms related to population (children and adolescents), concept (health-related physical fitness components) and context (HIV infection).

RESULTS

The search resulted in 7545 studies. After duplicate removal, titles and abstracts reading and full text assessment, 246 studies were included in the scoping review. Body composition was the most investigated component (n = 244), followed by muscular strength/endurance (n = 23), cardiorespiratory fitness (n = 15) and flexibility (n = 4). The World Health Organization growth curves, and nationals' surveys were the most reference values applied to classify body composition (n = 149), followed by internal cut-points (n = 30) and cut-points developed through small populations (n = 16). Cardiorespiratory fitness was classified through cut-points from three different assessment batteries, as well as cut-points developed through studies with small populations, muscular strength/endurance and flexibility were classified through the same cut-points from five different assessment batteries.

CONCLUSIONS

The research on muscular strength/endurance, cardiorespiratory fitness and flexibility has been scarcely explored. The lack of studies that investigated method usability as well as reference values was evidenced.

High resting energy expenditure, less fat-free mass, and less muscle strength in HIV-infected children: a matched, cross-sectional study

Background and aims

Many improvements have been made in the treatment of human immunodeficiency virus (HIV) in pediatric patients; however, challenges remain in terms of achieving normal growth, body composition, and metabolism during treatment, etc. Current nutritional recommendations are based on studies performed in adults, with limited data on the HIV-infected pediatric population. Therefore, this study aimed to compare the resting energy expenditure (REE) of asymptomatic HIV-infected pediatric patients with healthy counterparts and to compare body composition, dietary intake, and physical activity between the two groups.

Methods

This was a cross-sectional study of asymptomatic HIV-infected children who were receiving antiretroviral therapy; the infected group was compared with the uninfected group, matched by age (± 6 months), sex, and body mass index (± 0.5 z-score). Participants were recruited between 2021 and 2022, as outpatients. In both groups, REE was determined by indirect calorimetry and body composition by bioelectrical impedance analysis and hand strength, measured using a hydraulic hand dynamometer.

Results

Seventy-eight participants were enrolled, where n = 39 HIV-infected children and n = 39 controls, with a mean age of 11.6 ± 3.4 years old. REE was significantly higher in the HIV group (1254.4 ± 334.7 kcal/day vs. 1124.7 ± 321 kcal/day, p = 0.013) than in the control group. Fat-free mass (FFM) was lower in the HIV group (28.2 ± 10.5 kg vs. 32 ± 11.2 kg, p = 0.001); this trend continued when the index skeletal muscle was evaluated (7.2 ± 1.2 vs. 7.6 ± 1.5, p = 0.04). The strength of the dominant hand was also lower in the HIV group (12 (8-18) kg vs. 20 (10.5-26) kg, p < 0.0001).

Conclusions

Children with asymptomatic HIV infection have higher REE than their uninfected peers. They also present decreased FFM, skeletal muscle mass index, and muscle strength. These parameters should be considered during nutritional assessment in this population to have a favorable impact on nutritional status and growth.

Official Position of the Brazilian Association of Bone Assessment and Metabolism (ABRASSO) on the evaluation of body composition by densitometry-part II (clinical aspects): interpretation, reporting, and special situations

OBJECTIVE

To present an updated and evidence-based guideline for the use of dual-energy x-ray absorptiometry (DXA) to assess body composition in clinical practice.

MATERIALS AND METHODS

This Official Position was developed by the Scientific Committee of the Brazilian Association of Bone Assessment and Metabolism (Associação Brasileira de Avaliação Óssea e Osteometabolismo, ABRASSO) and experts in the field who were invited to contribute to the preparation of this document. The authors searched current databases for relevant publications in the area of body composition assessment. In this second part of the Official Position, the authors discuss the interpretation and reporting of body composition parameters assessed by DXA and the use of DXA for body composition evaluation in special situations, including evaluation of children, persons with HIV, and animals.

CONCLUSION

This document offers recommendations for the use of DXA in body composition evaluation, including indications, interpretation, and applications, to serve as a guiding tool in clinical practice and research for health care professionals in Brazil.

Developing an Impedance Based Equation for Fat-Free Mass of Black Preadolescent South African Children

Bioelectrical impedance analysis (BIA) is a practical alternative to dual-energy X-ray absorptiometry (DXA) for determining body composition in children. Currently, there are no population specific equations available for predicting fat-free mass (FFM) in South African populations. We determined agreement between fat-free mass measured by DXA (FFM_DXA) and FFM calculated from published multi-frequency bioelectrical impedance prediction equations (FFM_BIA); and developed a new equation for predicting FFM for preadolescent black South African children. Cross-sectional data on a convenience sample of 84 children (mean age 8.5 ± 1.4 years; 44 {52%} girls) included body composition assessed using Dual X-ray Absorptiometry (FFM_DXA) and impedance values obtained from the Seca mBCA 514 Medical Body Composition analyzer used to calculate FFM using 17 published prediction equations (FFM_BIA). Only two equations yielded FFM estimates that were similar to the DXA readings (p > 0.05). According to the Bland–Altman analysis, the mean differences in FFM (kg) were 0.15 (LOA: −2.68; 2.37) and 0.01 (LOA: −2.68; 2.66). Our new prediction equation, FFM=105.20+0.807×Sex+0.174×Weight+0.01×Reactance+15.71×log(RI), yielded an adjusted R² = 0.9544. No statistical shrinkage was observed during cross-validation. A new equation enables the BIA-based prediction of FFM in the assessment of preadolescent black South African children.

Longitudinal Changes in Body Composition by Dual-energy Radiograph Absorptiometry Among Perinatally HIV-infected and HIV-uninfected Youth: Increased Risk of Adiposity Among HIV-infected Female Youth

BACKGROUND

Combination antiretroviral therapy has allowed youth with perinatal HIV infection (PHIV+) to live into adulthood, but many youth may experience metabolic and body composition changes that predispose to greater cardiovascular disease (CVD) risk. This longitudinal study evaluated changes in body composition measured by dual-energy radiograph absorptiometry (DXA) in a cohort of PHIV+ youth compared with HIV- controls over a 7-year period.

METHODS

PHIV+ youth and HIV- controls were prospectively enrolled in a single-site study to assess nutrition and CVD risk. Anthropometrics and DXA scans were longitudinally obtained to assess percent body fat and regional fat distribution. Using general linear models, we analyzed differences in body composition and anthropometric measures by sex between PHIV+ youth and controls over time.

RESULTS

Two hundred thirty-five participants (156 PHIV+ and 79 HIV- controls) with at least 1 DXA performed since study enrollment were included for analysis. During the study period, 471 DXAs were obtained in the PHIV+ group and 95 in HIV- controls. PHIV+ females demonstrated greater increase in weight and body mass index over time compared with HIV- females, and significant increases in total percent body fat [estimate = 1.212 (95% confidence interval: 0.837-1.587) percent per year; P < 0.001) and percent trunk fat [1.3818 (95% confidence interval: 0.922-1.84); P < 0.001] compared with HIV- females and PHIV+ males.

CONCLUSIONS

PHIV+ females demonstrate an unfavorable change in fat redistribution and percent body fat over time that exceeds the pattern seen in PHIV+ males or HIV- females. Providers should have heightened awareness of body composition changes of PHIV+ females that may eventually lead to increased CVD risk.

Accuracy of octa-polar bioelectrical impedance analysis for the assessment of total and appendicular body composition in children and adolescents with HIV: comparison with dual energy X-ray absorptiometry and air displacement plethysmography

BACKGROUND

Body composition analysis has been used to investigate fat mass (FM) and bone mineral content (BMC) in children and adolescents diagnosed with HIV. Investigating the validity of bioelectrical impedance analysis (BIA) is interesting with respect to testing useful techniques for monitoring body composition in children and adolescents in clinical practice. The present study aimed to determine the validity of body composition analysis by BIA compared to dual-energy X-ray absorptiometry (DXA) and air displacement plethysmography (ADP) in children and adolescents an HIV diagnosis.

METHODS

Sixty-four children and adolescents (35 females and 29 males) with a mean (SD) age of 12.22 (2.13) years and with an HIV diagnosis participated in the study. Fat-free mass (FFM), FM and body fat percentage (%BF) were obtained by BIA for comparison with DXA and ADP. Segmented FM (trunk, legs and arms), lean soft tissue mass (LSTM) (total and segmented) and BMC were obtained by BIA for comparison with DXA.

RESULTS

BIA presented a clinically acceptable correlation with DXA and ADP for FFM. Values found by BIA were underestimated compared to ADP, and overestimated compared to DXA. BIA presented a clinically acceptable correlation with DXA for LSTM estimates (total and segmented parameters) in both sexes (underestimating FM and overestimating LSTM). For other components (%BF, FM and BMC), BIA had a clinically unacceptable correlation with the reference methods in both sexes.

CONCLUSIONS

BIA was suitable for evaluating FFM and LSTM in children and adolescents with an HIV diagnosis. For FM, %BF and BMC, BIA was not suitable for performing an evaluation in both sexes.

Body composition estimation in children and adolescents by bioelectrical impedance analysis: A systematic review

BACKGROUND

Bioelectrical impedance analysis (BIA) has commonly been used to assess the body composition of children and adolescents. BIA validation studies have found distinct correlation values with reference methods.

OBJECTIVES

To assess the reproducibility, correlation and mean differences in body composition estimated by BIA and reference methods, we systematically reviewed the literature in the pediatric population.

METHOD

The search for articles was conducted in March 2016 and was limited to articles published from 2005 to 2015 in the PubMed, Embase, EBSCO, Web of Science, Scopus and SciELO databases. Two reviewers independently performed data selection and extraction of studies that investigated the BIA validity, responsiveness, reliability and/or measurement error (reproducibility) to estimate body composition in children and adolescents with an average age ≤ 18 years.

RESULTS

The search produced 48 articles. Almost perfect reproducibility was found in the body fat percentage estimated by BIA, and there was almost perfect correlation between the BIA ratings and reference methods for fat mass and fat-free mass. Regarding component estimates, BIA underestimated the fat mass in both sexes.

CONCLUSIONS

The body fat percentage estimated by BIA exhibited almost perfect reproducibility. The fat mass and fat-free mass estimated by BIA correlated almost perfectly with the reference methods in both sexes. BIA underestimated the fat mass in both sexes.

A comparison study of portable foot-to-foot bioelectrical impedance scale to measure body fat percentage in Asian adults and children

Objective. To compare the measurements of body fat percentage (BF%) using the foot-to-foot bioelectrical impedance analysis (FTF-BIA) with the direct segmental multifrequency BIA (DSM-BIA). Methods. There were 36 men and 52 women (37.1 ± 14.3 years) with 57% Malays, 30% Chinese, and 13% Indian. For children, there were 45 boys and 26 girls (11.5 ± 2.5 years) with 52% Malay, 15% Chinese, and 33% Indian. Results. Mean height for men was 168.4 cm, 11 cm taller than women. Men were 10 kg heavier than women at 70 kg. BF% in women was 32% and 33% whereas BF% in men was 23% and 25% when measured using FTF-BIA and DSM-BIA, respectively. In children, BF% measured with FTF-BIA and DSM-BIA was 49% and 46%, respectively. The correlations were significant for men (r = 0.92, SEE = 2.80), women (r = 0.91, SEE = 3.31), boys (r = 0.95, SEE = 5.44), and girls (r = 0.96, SEE = 5.27). The BF% in underweight/normal (r = 0.92, SEE = 2.47) and that in overweight/obese adults (r = 0.89, SEE = 3.61) were strongly correlated. The correlations were significant in normal/underweight (r = 0.94, SEE = 3.78) and obese/overweight children (r = 0.83, SEE = 6.49). All ethnic groups showed significant correlation with BF%. Malay adults (r = 0.92, SEE = 3.27) and children (r = 0.94, SEE = 0.88) showed significant mean differences in BF%. Conclusion. The FTF-BIA showed higher accuracy for all normal/underweight and Chinese group with acceptable overestimation in children and underestimation in adults. Caution should be taken when interpreting BF% depending on gender, BMI, and ethnicity.