Background: Atherosclerosis is the most common complication of diabetes. Correction of hyperglycaemia helps to prevent microvascular complications but has little effect on macrovascular disease. Post-hoc analyses of diabetic subpopulations in lipid intervention trials suggest that correction of lipoprotein abnormalities will lead to a decrease in coronary-artery disease. The Diabetes Atherosclerosis Intervention Study (DAIS) was specifically designed to assess the effects of correcting lipoprotein abnormalities on coronary atherosclerosis in type 2 diabetes.
Methods: 731 men and women with type 2 diabetes were screened by metabolic and angiographic criteria. 418 were randomly assigned micronised fenofibrate (200 mg/day) or placebo for at least 3 years. They were in good glycaemic control (mean haemoglobin A1c 7.5%), had mild lipoprotein abnormalities, typical of type 2 diabetes, and at least one visible coronary lesion. Half had no previous clinical coronary disease. Initial and final angiograms followed a standard protocol and were analysed by a computer-assisted quantitative approach. Missing data for the primary endpoints (minimum lumen diameter, mean segment diameter, and mean percentage stenosis) were imputed. Analyses were by intention to treat.
Findings: Total plasma cholesterol, HDL-cholesterol, LDL-cholesterol, and triglyceride concentrations all changed significantly more from baseline in the fenofibrate group (n=207) than in the placebo group (n=211). The fenofibrate group showed a significantly smaller increase in percentage diameter stenosis than the placebo group (mean 2.11 [SE 0.594] vs 3.65 [0.608]%, p=0.02), a significantly smaller decrease in minimum lumen diameter (-0.06 [0.016] vs -0.10 [0.016] mm, p=0.029), and a non-significantly smaller decrease in mean segment diameter (-0.06 [0.017] vs -0.08 [0.018] mm, p=0.171). The trial was not powered to examine clinical endpoints, but there were fewer in the fenofibrate group than the placebo group (38 vs 50).
Interpretation: DAIS suggests that treatment with fenofibrate reduces the angiographic progression of coronary-artery disease in type 2 diabetes. This effect is related, at least partly, to the correction of lipoprotein abnormalities, even those previously judged not to need treatment.