Excessive weight gain following antiretroviral therapy (ART) is common and may predispose individuals to HIV-associated metabolic syndrome, sometimes leading to ART discontinuation and/or poor adherence. The objective of this study is to understand predictors of severe weight/body mass index (BMI) gain in individuals initiating ART.
This was a retrospective analysis of the ACTG A5257 study, where ART-naïve HIV-infected individuals were randomized to one of 3 regimens: atazanavir/ritonavir (ATV/r), darunavir/ritonavir (DRV/r), or raltegravir (RAL) each in combination with tenofovir disoproxil fumarate/emtricitabine. Severe weight/BMI gain outcomes over 96 weeks were defined two ways: (1) percent weight increase ≥ 10%; (2) an upward change in BMI category. Among those underweight at baseline, only those who were overweight or higher at follow-up were included in both outcomes. Logistic regression was used to examine the association between participant characteristics and severe weight/BMI gain.
The study population (N=1,809) was 76% male, largely black non-Hispanic (41.9%) and white non-Hispanic (34.1%), with a mean baseline weight of 79 kg and BMI of 26 kg/m^2. Over 96 weeks, the average weight increased by 3.8 kg and BMI by 1.3 kg/m^2. Those with severe weight gain had a mean increase of 14.9 kg (N=373), and those with severe BMI gain had a mean increase of 4.4 kg/m^2 (N=361). The odds of severe weight gain were 1.55 times higher for black non-Hispanic compared to white non-Hispanic individuals (95% CI: 1.10 to 2.20; p=0.013). The odds of severe weight gain were 2.52 times higher for every 1 log (10-fold) higher in baseline HIV-1 RNA (95% CI: 2.00 to 3.16; p<0.0001), and 1.28 times higher for every 100 cell/mm^3 lower in baseline CD4+ count (95% CI: 1.18 to 1.39; p<0.0001). Results were similar for severe BMI. Results also suggested that treatment with protease inhibitors vs RAL may be protective against severe weight/BMI gain. The odds of severe weight gain were significantly lower for ATV/r vs RAL (OR: 0.72 [95% CI: 0.53 to 0.99]; p=0.043), while odds of severe BMI gain were significantly lower for DRV/r vs RAL (OR: 0.73 [95% CI: 0.53 to 0.99]; p=0.041).
Predictors of severe weight/BMI gain in this population included black race, higher baseline disease severity, and use of RAL. Understanding factors predisposing individuals to unhealthy weight gain may help better manage metabolic complications of HIV.