Body Impedance Analysis and Skinfold Measurements as Low-cost Alternatives to DXA for Monitoring Lipodystrophy in CLWH in South Africa
Name: Bryce Killingsworth
School: Vagelos College of Physicians and Surgeons, Class of 2024
Mentor: Michael T. Yin, MD, MS
Abstract
The research question for this study was: How do skinfold measurement and body impedance analysis equations (BIA) perform as alternatives to dual x-ray absorptiometry (DXA) for monitoring body fat percentage (BFP) in a population of children living with HIV (CLWH) in South Africa? CLWH experience lipodystrophy, likely due antiretroviral treatment. Individuals with lipodystrophy can face stigma which may affect treatment adherence. BFP is one parameter that captures information about fat distribution. The gold-standard method for measuring BFP is DXA. This technology may be too expensive to implement in under-resourced settings. Skinfold and BIA equations are both more affordable alternatives to DXA. However, both technologies rely on algorithms calibrated to reference populations that may not be representative of the children included in this study. 410 children were included in this study with 53.4% of them CLHW from perinatal infection. They were enrolled from two sites in Johannesburg. Spearman correlation coefficients were used to analyze correlation between BFP measurement methods. No BIA or skinfold equation reproduced BFP results accurately. There was high correlations for some relationships between DXA and Skinfold and BIA. Equations with less variables performed best. These results demonstrate the challenge of finding alternatives to DXA for monitoring lipodystrophy in CLHW in low-resource settings. BIA and skinfold algorithms may be mis-calibrated for different populations in global health settings. Large correlation coefficients between DXA and the older BIA and skinfold algorithms demonstrates their potential to be useful tools, however further development and study is needed for implementation in sub-Saharan Africa.