Modification of Therapy From Insulin to Chlorpropamide Decreases HDL Cholesterol in Patients With Non-Insulin-Dependent Diabetes Mellitus

In 27 patients with non-insulin-dependent diabetes mellitus, we determined fasting serum glucose, hemoglobin A,, body weight, serum triglycerides, cholesterol, low-density lipoprotein cholesterol (LDL-chol), high-density lipoprotein cholesterol (HDL-chol), and very-low-density lipoprotein cholesterol during treatment with insulin and several months after changing treatment to chlorpropamide. In five patients, diabetic control deteriorated to the point where insulin was reinitiated. In the remaining 22 patients, despite a significant decrease in weight (122 ± 5 vs. 114 ± 5% ideal body wt; P < .025) on chlorpropamide, HDL-chol fell from 49 ± 4 to 40 ± 4 mg/dl (P < .01) when therapy was modified from insulin to the sulfonylurea. There was a concomitant increase in LDL-chol:HDL-chol from 3.6 ± 0.3 to 4.4 ± 0.5 (P < .05). In the 5 patients in whom insulin was reinstituted, HDL-chol increased to its previous level on insulin (P < .05). Changing antidiabetic medication from insulin to sulfonylureas may alter the lipoproteins in a manner that increases cardiovascular risk.