Weight Gain and Incident Diabetes Among HIV-Infected Veterans Initiating Antiretroviral Therapy Compared With Uninfected Individuals

Abstract

Background: The health implications of weight gain after antiretroviral therapy (ART) for HIV infection are not well characterized and may differ from weight gain among uninfected individuals. We use data from the Veterans Aging Cohort Study to determine whether weight gain after ART has a similar association with incident type 2 diabetes mellitus (DM) as weight gained among HIV-uninfected (uninfected) individuals.

Methods: We explored associations of weight gain and incident diabetes (A1c ≥ 6.5%), in the Veterans Aging Cohort Study, a national observational study of HIV-infected (HIV+) individuals demographically matched 1:2 to uninfected controls. From 2000 to 2011, weight change was assessed in the year following ART initiation for HIV+ individuals and date of first available body mass index for uninfected individuals. We estimated hazard ratios (HRs) and 95% confidence intervals (CIs) adjusted for baseline body mass index using Cox regression.

Results: HIV+ individuals had lower prevalence of DM at baseline (12% HIV+, 23% uninfected) and lower incident diabetes (5% HIV+, 11% uninfected). The association of weight gain with risk of DM was linear for HIV+ and uninfected but the slope of the association was steeper for HIV+. For each 5 pounds of weight gained, HIV+ had 14% increased risk of DM (HR, 1.14; 95% CI: 1.10 to 1.17) and uninfected individuals had 8% increased risk (HR, 1.08; 95% CI: 1.07 to 1.10) (P < 0.01 for interaction).

Conclusions: Weight gained in the first year after ART initiation is associated with greater risk of DM than that among uninfected individuals. HIV+ individuals initiating ART who are not underweight should avoid substantial weight gain.

Figure 1

Patient flow diagram.

Figure 2

Rate of incident diabetes mellitus during median follow-up of 5.0 years, by baseline BMI, according to amount of weight gained in 12 months, in HIV+ and Uninfected Veterans, 2000–2011. (BMI <18.5 not shown due to sparse data).

Figure 3

Relative risk of diabetes in HIV+(N = 6,845) and uninfected (N = 24,345) Veterans, by weight change in a one-year interval compared to those without weight change, adjusted for age, race, sex, baseline BMI, smoking, HCV infection and calendar year at baseline. (Excludes those with baseline BMI <18.5 kg/m²)