Comparing the effects of insulin glargine and thiazolidinediones on plasma lipids in type 2 diabetes: A patient-level pooled analysis

Background: The prevalence of dyslipidaemia and the risk of cardiovascular disease are elevated in patients with type 2 diabetes. This analysis compared the effects of insulin glargine versus thiazolidinediones (TZDs) on lipid profiles. Methods: Patient-level data were pooled from two randomized clinical studies. The population included 552 men and women aged >18years, diagnosed with type 2 diabetes for at least 6months, on metformin and/or sulphonylurea, and with A _1C ≥7.5% and <12.0% at screening. Lipid outcome measures included change from baseline in lipid levels [low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), non-high-density lipoprotein cholesterol (non-HDL-C), total cholesterol, triglycerides, and free fatty acids] and attainment of lipid goals for LDL-C, non-HDL-C, and triglycerides. Results: Both insulin glargine and TZDs improved lipid profiles from baseline values. Compared with TZDs, treatment with insulin glargine led to 7.9% greater reduction in LDL-C (p<0.0003), 7.5% greater reduction in non-HDL-C (p<0.0001), and 7.8% greater reduction in total cholesterol (p<0.0001), whereas the HDL-C increase with TZD was 7.6% greater than that with insulin glargine (p<0.0001). The percentage of patients attaining the lipid goals was comparable between insulin glargine and pioglitazone, but lower for rosiglitazone. Insulin glargine improved glycaemic control more than TZDs; however, insulin glargine caused more hypoglycaemia. Treatment with TZDs caused more weight gain and peripheral oedema. Conclusion: These findings suggest that the favourable effects of insulin glargine on plasma lipid profiles should be considered among the advantages of treatment with insulin glargine as they are for TZDs.