2250. Metformin for Preventing Diabetes Mellitus in HIV-Infected Patients with Prediabetes: A Randomized Controlled Trial

Abstract

Background. Both HIV and diabetes mellitus (DM) increase the risk for cardiovascular diseases. Prediabetes (PreDM), a condition preceding DM, is commonly observed in HIV-infected patients receiving antiretroviral therapy (ART). Both metformin and lifestyle interventions have been shown to reduce risk of progression to DM in non-HIV-infected population. This study aimed to evaluate the efficacy of metformin for preventing DM in HIV-infected patients. Methods. An open-label randomized controlled clinical trial was conducted in HIVinfected patients with PreDM. Patients were randomized into two groups: metformin group (received metformin) and control group (not received metformin). Patients in both groups were counseled regarding diet control and lifestyle modification and followed for 6 months. The primary endpoint was the development of DM. Fasting plasma glucose (FPG), 2-hour 75-gm oral glucose tolerance test, HbA1c, computer-based homeostatic model assessment index of β-cell function (HOMA%B) and insulin resistance (HOMA-IR) were analyzed. Results. Seventy-four patients were enrolled, 37 in each group. Mean age was 49.6 years and 68.9% were males. At baseline, mean CD4 cell count was 570 cells/mm3 and mean body mass index (BMI) was 24.6 kg/M2. Baseline characteristics including age, sex, BMI, waist-hip (W/H) ratio, duration of ART, ART regimen, CD4 cell count and HIV RNA were similar between two groups (P > 0.05). Mean FPG, 2hPG, HbA1c, HOMA%B and HOMA-IR at baseline were also similar between two groups (P > 0.05). At 6 months, one patient in metformin group and two in control group developed DM [risk reduction 2.70%; 95% CI, -9.09% to +15.20%]. Mean HbA1c significantly decreased from baseline only in metformin group. HOMA-IR at 6 months was significantly lower in metformin group (1.086 vs. 1.478, P = 0.042). However, BMI, W/H ratio, FPG, 2hPG, HbA1c, and HOMA%B at 6 months were not significantly different between two groups (P > 0.05). No patient had adverse effects that led to discontinuation of metformin. No cardiovascular event was observed in study period. Conclusion. Metformin appears to improve insulin resistance and prevent progression to DM in HIV-infected patients with PreDM. Further study with longer study period is needed to evaluate long-term benefit of metformin.