Effect of simvastatin on insulin sensitivity in type 2 diabetic subjects

Objective: To study the effect of Simvastatin therapy on insulin sensitivity in type 2 Diabetes mellitus subjects. Methodology: This is a randomized case control study, conducted at Baqai Institute of Diabetology and Endocrinology, Karachi, Pakistan. The study was conducted in 100 type 2 diabetes subjects of both sexes. Patients were randomized into two groups. Fifty patients were given Simvastatin 40mg/day for three months while 50 patients were used as controls. Both groups had similar anthropometric (age, duration of diabetes, BMI and Blood pressure) and biochemical (serum creatinine, fasting plasma glucose, fasting insulin level and lipid profile) characteristics. Insulin resistance was assessed by calculating homeostasis model assessment for insulin resistance (HOMA-IR) before and after 3 months of simvastatin treatment (40mg/day). Results: Simvastatin (40mg/day) markedly decreased cholesterol, triglycerides and LDL levels but did not significantly affect insulin sensitivity as determined by HOMA-IR. However it improved insulin sensitivity in subjects having insulin resistance. (HOMA IR reduction 1.92; p=0.001) Conclusion: Short term simvastatin therapy (3 months) had no effect on insulin sensitivity, but had a significant lipid lowering effect in all the subjects.