Effects of lifestyle modification and metformin on atherosclerotic indices among HIV-infected patients with the metabolic syndrome

Abstract

Objective Metabolic abnormalities including diabetes, dyslipidemia, hypertension, and abdominal obesity occur commonly in HIV patients, are associated with increased coronary artery calcification (CAC), and contribute to increased cardiovascular disease (CVD) in this population. We hypothesized that lifestyle modification (LSM) and metformin would improve CVD indices in HIV patients with metabolic syndrome. Design A randomized, placebo controlled trial to investigate LSM and metformin, alone and in combination, over one year, among 50 HIV-infected patients with metabolic syndrome. Methods We assessed CAC, cardiovascular and metabolic indices. Results Among the participants, duration of HIV-infection was 14±1 yr and duration of antiretroviral therapy was 6±1 yr. Metformin-treated subjects demonstrated significantly less progression of CAC (−1±2 vs. 33±17, P=0.004, metformin vs. placebo) whereas the effect of LSM on CAC progression was not significant (8±6 vs. 21±14, P=0.82, LSM vs. no LSM). Metformin had a significantly greater effect on CAC than LSM (P=0.01). Metformin-treated subjects also demonstrated less progression in calcified plaque volume (−0.4±1.9 vs. 27.6±13.8 mm3, P=0.008) and improved HOMA-IR (P=0.05) compared to placebo. Subjects randomized to LSM vs. no LSM showed significant improvement in HDL (P=0.03), hsCRP (P=0.05), and cardiorespiratory fitness. Changes in CAC among the 4 groups: 1) no LSM, placebo (43±30); 2) LSM, placebo (19±7); 3) no LSM, metformin (1±1); and 4) LSM, metformin (−4±6) were different (P=0.03 for ANOVA and linear trend across groups), the majority of this effect was mediated by metformin. Results are mean ± SEM. Conclusion Metformin prevents plaque progression in HIV-infected patients with the metabolic syndrome.

Effectiveness of Progressive Resistive Exercise (PRE) in the context of HIV: systematic review and meta-analysis using the Cochrane Collaboration protocol

“…Five studies (25%) had low risk for detection bias because authors reported that outcome assessors were blinded to group allocation [26–28, 31, 32] (Fig. 2).…”

Comparison of Insulin Resistance to Coronary Atherosclerosis in Human Immunodeficiency Virus Infected and Uninfected Men (from the Multicenter AIDS Cohort Study)

“…Exercise, metformin, and thiazolidenedione therapy have all been shown to decrease IR in HIV-infected populations, 23 and metformin, in particular, has been shown to halt the progression of calcified plaque in HIV-infected individuals. 24 Whether these strategies will also decrease CVD events in HIV-infected persons is unknown.…”

Effects of aerobic and resistance exercise alone or combined on strength and hormone outcomes for people living with HIV. A meta-analysis

“…Two studies [58,60] reported strength outcomes and pro-inflammatory interleukins (IL-6 and IL-1β). The study by Fitch et al [69] reported strength outcomes and c-reactive protein (CRP). Long-term effects (> 4 months) of exercise were identified on three [66,69,73] of the 13 included studies.…”