Effects of Pravastatin and Atorvastatin on HDL Cholesterol and Glucose Metabolism in Patients with Dyslipidemia and Glucose Intolerance: The PRAT Study

Aims: While statins have the property of increasing high-density lipoprotein cholesterol (HDL-C) in addition to lowering low-density lipoprotein cholesterol (LDL-C), a potential adverse effect on glucose metabolism has raised a concern over statin therapy. In a comparative trial, we investigated the effects of low-dose pravastatin and atorvastatin on HDL-C and glucose metabolism in patients with elevated LDL-C levels and glucose intolerance. Methods: Eligible patients were men aged >= 20 years or postmenopausal women who had LDL-C >= 140 mg/dL, HDL-C< 80 mg/dL, and triglycerides <500 mg/dL and who had glucose intolerance. The patients were randomly allocated to either pravastatin (10 mg/day) or atorvastatin (10 mg/day) treatment for 12 months in an unblinded fashion. The percent changes from the baseline were compared between the treatments. Results: Of 202 patients who were randomized to either of the two treatments, 195 patients started the study medication, and 187 patients underwent the follow-up measurements at 6 or 12 months (pravastatin, n=93; atorvastatin, n=94). HDL-C increased by 4.3% (p=0.03) in the pravastatin group and by 5.8% (p=0.0005) in the atorvastatin group and showed no between-group difference (p=0.38). LDL-C decreased substantially in both groups (pravastatin, 21.5%; atorvastatin, 35.5%), and the decrease was much greater in the atorvastain group (p<0.0001). HbA1c slightly increased in both groups, but showed no measurable difference in the increase between the two treatments (p=0.30). Conclusion: Pravastatin and atorvastatin of 10 mg per day each increased HDL-C by almost the same extent. These two statins did not show a differential effect on glucose metabolism.