co-administration of vitamin e and atorvastatin improves insulin sensitivity and peroxisome proliferator-activated receptor-γ expression in type 2 diabetic patients: a randomized double-blind clinical trial

background: negative effects of statins on glucose metabolism have been reported. the present study aimed to investigate the effects of co-administration of vitamin e and atorvastatin on glycemic control in hyperlipidemic patients with type 2 diabetes mellitus (t2dm). methods: a randomized double-blind clinical trial was conducted at vali-e-asr teaching hospital (zanjan, iran) from july 2017 to march 2018. a total of 30 t2dm female patients were allocated to two groups, namely atorvastatin with placebo (n=15) and atorvastatin with vitamin e (n=15). the patients received daily 20 mg atorvastatin and 400 iu vitamin e or placebo for 12 weeks. anthropometric and biochemical measures were recorded pre- and post-intervention. peroxisome proliferatoractivated receptor-γ (ppar-γ) expression was measured in peripheral blood mononuclear cells (pbmcs). independent sample t test and paired t test were used to analyze between- and within-group variables, respectively. the analysis of covariance (ancova) was used to adjust the effect of baseline variables on the outcomes. p 0.05 was considered statistically significant. results: after baseline adjustment, there was a significant improvement in homeostatic model assessment for insulin resistance (homa-ir) (p=0.04) and serum insulin (p 0.001) in the atorvastatin with vitamin e group compared to the atorvastatin with the placebo group. in addition, co-administration of vitamin e with atorvastatin significantly upregulated ppar-γ expression (or=5.4, p=0.04) in the pbmcs of t2dm patients. conclusion: co-administration of vitamin e and atorvastatin reduced insulin resistance and improved ppar-γ mrna expression. further studies are required to substantiate our findings.