The effect of atorvastatin on pancreatic beta cell requirement in women with polycystic ovary syndrome

Background There is an increased risk of developing T2DM in women with polycystic ovary syndrome (PCOS), and there is evidence that statins improve metabolic parameters in these patients. However, there are some data to show that statins increase the risk of incipient diabetes. Materials and methods We have previously shown that 12 weeks of atorvastatin improves insulin resistance when measured using HOMA-IR. This post hoc analysis was designed to look at the effect of atorvastatin on pancreatic β cell function using HOMA-β in the same study. In this randomised, double-blind placebo controlled study, 40 medication-naïve patients with PCOS were randomised to either atorvastatin 20 mg daily or placebo for 3 months. A 3-month extension study for both groups of patients was undertaken with metformin 1500 mg daily after completing initial 3 months of atorvastatin or placebo. Results There was a significant reduction in HOMA-β (240 ± 3.2 vs 177 ± 2.3; P value <0.01) after 12 weeks of atorvastatin treatment, which was maintained by metformin in the subsequent 12 weeks. There were no changes in HOMA-β after the placebo or after subsequent metformin treatment. There was no linear correlation between reduction in HOMA-β with improvement of free androgen index (FAI) (r2 = 0.02; P = 0.72), testosterone (r2 = 0.13; P = 0.49), SHBG (r2 = 0.22; P = 0.48), hsCRP (r2 = 0.19; P = 0.64), triglycerides (r2 = 0.09; P = 0.12), total cholesterol (r2 = 0.11; P = 0.32) or LDL-C (r2 = 0.19; P = 0.38). Conclusion Treatment with atorvastatin for 12 weeks in women with PCOS significantly reduced HOMA-β. This could be potentially due to fall in β-cell requirement with improvement of insulin resistance rather than a reduction of β-cell function.