Treatment effects on serum lipoprotein lipids, apolipoproteins and low density lipoprotein particle size and relationships of lipoprotein variables to progression of coronary artery disease in the Bezafibrate Coronary Atherosclerosis Intervention Trial (B

Objectives. To investigate the mechanisms by which bezafibrate retarded the progression of coronary lesions in the Bezafibrate Coronary Atherosclerosis Intervention Trial (BECAIT), we examined the relationships of on-trial lipoproteins and lipoprotein subfractions to the angiographic outcome measurements. Background. BECAIT, the first double-blind, placebo-controlled, randomized serial angiographic trial of fibrate compound, showed that progression of focal coronary atherosclerosis in young survivors of myocardial infarction could be retarded by bezafibrate treatment. Methods. total of 92 dyslipoproteinemic men who had survived first myocardial infarction before the age of 45 years were randomly assigned to treatment for 5 years with bezafibrate (200 mg three times daily) or placebo; 81 patients underwent baseline and at least one post-treatment coronary angiography. Results. In addition to the decrease in very low density lipoprotein (VLDL) cholesterol (−53%) and triglyceride (−46%) and plasm apolipoprotein (apo) B (−9%) levels, bezafibrate treatment resulted in significant increase in high density lipoprotein-3 (HDL3) cholesterol (+9%) level and shift in the low density lipoprotein (LDL) subclass distribution toward larger particle species (peak particle diameter +0.32 nm). The on-trial HDL3 cholesterol and plasm apo B concentrations were found to be independent predictors of the changes in mean minimum lumen diameter (r = −0.23, p < 0.05), and percent (%) stenosis (r = 0.30, p < 0.01), respectively. Decreases in small dense LDL and/or VLDL lipid concentrations were unrelated to disease progression. Conclusions. Our results suggest that the effect of bezafibrate on progression of focal coronary atherosclerosis could be at least partly attributed to rise in HDL3 cholesterol and decrease in the total number of apo B-containing lipoproteins.