Objective: To compare the effect that initiating different antiretroviral therapy (ART) regimens has on weight, BMI, and lean body mass (LBM) and explore how changes in body composition are associated with bone mineral density (BMD).
Methods: A5224s was a sub-study of A5202, a prospective trial of 1857 ART-naive participants randomized to blinded abacavir–lamivudine (ABC/3TC) or tenofovir DF–emtricitabine (TDF/FTC) with open-label efavirenz (EFV) or atazanavir–ritonavir (ATV/r). All participants underwent dual-energy absorptiometry (DXA) and abdominal computed tomography for body composition. Analyses used two-sample t-tests and linear regression.
Results: A5224s included 269 participants: 85% men, 47% white non-Hispanic, median age 38 years, HIV-1 RNA 4.6 log10 copies/ml, and CD4+ cell count 233 cells/μl. Overall, significant gains occurred in weight, BMI, and LBM at 96 weeks postrandomization (all P < 0.001). Assignment to ATV/r (vs. EFV) resulted in significantly greater weight (mean difference 3.35 kg) and BMI gain (0.88 kg/m2; both P = 0.02), but not LBM (0.67 kg; P = 0.15), whereas ABC/3TC and TDF/FTC were not significantly different (P ≥ 0.10). In multivariable analysis, only lower baseline CD4+ cell count and higher HIV-1 RNA were associated with greater increase in weight, BMI, or LBM. In multivariable analyses, increased LBM was associated with an increased hip BMD.
Conclusion: ABC/3TC vs. TDF/FTC did not differ in change in weight, BMI, or LBM; ATV/r vs. EFV resulted in greater weight and BMI gain but not LBM. A positive association between increased LBM and increased hip BMD should be further investigated through prospective interventional studies to verify the impact of increased LBM on hip BMD.
aUniversity of Colorado-Anschutz Medical Campus; Aurora, Colorado
bHarvard School of Public Health, Boston
cBrigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
dLos Angeles Biomedical Research Institute at Harbor-UCLA Medical Center, Torrance, California
eUniversity of Pennsylvania, Philadelphia, Pennsylvania
fGilead Sciences, Foster City, California
gViiV Healthcare, Research Triangle, North Carolina
hSocial and Scientific Systems, Inc., Silver Spring, Maryland
iCase Western Reserve University, Cleveland, Ohio, USA.
Correspondence to Grace A. McComsey, MD, Case Western Reserve University, 11100 Euclid Ave, Cleveland, OH44106, USA. E-mail: email@example.com
Received 26 February, 2013
Revised 30 March, 2013
Accepted 2 April, 2013