Sex hormones, insulin resistance, and diabetes mellitus among men with or at risk for HIV infection

Objective: To examine the relationship of free testosterone (FT) and sex hormone-binding globulin (SHBG) with insulin resistance and diabetes mellitus (DM) in HIV disease. Design: Cross-sectional analysis from 322 HIV-uninfected and 534 HIV-infected men in the Multicenter AIDS Cohort Study. Methods: The main outcomes were DM and homeostasis model assessment-insulin resistance (HOMA-IR). DM was defined as fasting serum glucose 126 or self-reported DM and use of DM medications. HOMA-IR was calculated from fasting serum glucose and fasting insulin. Results: Compared with HIV-uninfected men in our sample, HIV-infected men were younger, with lower body mass index, and more often black. HIV-infected men had lower FT (P < 0.001) and higher SHBG (P < 0.0001). The adjusted odds ratio for DM was 1.98 (95% confidence interval: 1.04 to 3.78); mean adjusted log HOMA-IR was 0.21 units higher in HIV-infected men (P < 0.0001). Log SHBG, but not log FT, was associated with DM (odds ratio = 0.44, 95% confidence interval: 0.25 to 0.80) in both groups. Log FT and log SHBG were inversely related to insulin resistance (P < 0.05 for both) independent of HIV. Conclusions: Compared with HIV-uninfected men, HIV-infected men had lower FT, higher SHBG, and more insulin resistance and DM. Lower FT and lower SHBG were associated with insulin resistance regardless of HIV serostatus. This suggests that sex hormones play a role in the pathogenesis of glucose abnormalities among HIV-infected men.