CLEARANCE OF CHYLOMICRON REMNANTS IN NORMOLIPIDEMIC PATIENTS WITH CORONARY-ARTERY DISEASE - CASE-CONTROL STUDY OVER 3 YEARS

Objective-To test the hypothesis that subjects who clear chylomicron r emnants slowly from plasma may be at higher risk of coronary artery di sease than indicated by their fasting plasma lipid concentrations. Des ign-Case control study over three years. Setting-An 800 bed general mu nicipal hospital. Subjects-85 normolipidaemic patients with coronary a rtery disease selected prospectively and matched with 85 normolipidaem ic subjects with normal coronary arteries on angiography. Intervention s-All subjects were given a vitamin A fat loading test which specifica lly labels intestinal lipoproteins with retinyl palmitate. Main outcom e measure-Postprandial lipoprotein metabolism. Results-The area below the chylomicron remnant retinyl palmitate curve was significantly incr eased in the coronary artery disease group as compared with the contro ls (mean 23.4 (SD 15.0) v 15.3 (8.9) mu mol/l.h; 95% confidence interv al of difference 4.37 to 11.82). Conclusions-Normolipidaemic patients with coronary artery disease had significantly higher concentrations o f chylomicron remnants in plasma than normolipidaemic subjects with no rmal coronary vessels. This may explain the mechanism underlying the s usceptibility to atherosclerosis of coronary artery disease patients w ith normal fasting lipid values. As diet and drugs can ameliorate the accumulation of postprandial lipoproteins in plasma, the concentration of chylomicron remnants should be measured in patients at high risk o f coronary artery disease.