Comparison of Body Composition Assessment Methods in Patients with Human Immunodeficiency Virus-Associated Wasting Receiving Growth Hormone

Context: Bioelectrical impedance spectroscopy (BIS) and skinfold anthropometry (SKF) have been used to monitor body composition among patients with HIV wasting; however, validation of these techniques during recombinant human GH (rhGH) treatment has not been performed. Objective: Our objective was to evaluate the degree of agreement between criterion measurements of dual-energy x-ray absorptiometry (DXA) and those of BIS and SKF in patients with HIV wasting treated with rhGH. Design and Setting: We conducted a randomized, double-blinded, placebo-controlled, two-period crossover trial at the University of Toronto and Mount Sinai Hospital (Toronto, Canada). Patients: A referred sample of 27 community-dwelling men with HIV-associated weight loss (≥10% over preceding 12 months) despite optimal antiretroviral therapy participated in the study. Intervention: Intervention was one daily injection of rhGH (6 mg) or placebo self-administered for 3 months in a crossover fashion with a 3-month washout. Main Outcome Measures: Fat-free mass (FFM) and fat mass (FM) were measured by BIS, SKF, and DXA before and after rhGH and placebo treatment. Results: FFMBIS was not significantly different from FFMDXA after rhGH treatment (P = 0.10). Mean differences (bias ± sd) according to Bland-Altman analysis were smaller for SKF than for BIS (P < 0.05) at all time points, yet treatment-induced change in FM was better detected with BIS than with SKF. BIS estimates of FFM and FM showed better agreement with those of DXA after rhGH treatment (1.6 ± 4.6 kg and −2.1 ± 3.9 kg) compared with baseline (3.8 ± 3.5 kg and −4.1 ± 3.6 kg) and placebo (2.7 ± 4.4 kg and −3.1 ± 4.6) (P < 0.05). BIS overestimated and SKF underestimated the treatment-induced changes in FFM and FM. Conclusions: SKF was more accurate than BIS when measuring body composition in patients with HIV wasting before and after rhGH treatment; nonetheless, the accuracy of BIS increased after treatment. Change in FM because of treatment was not accurately assessed with SKF.