OXIDISABILITY OF LOW-DENSITY LIPOPROTEINS IN PATIENTS WITH CAROTID ORFEMORAL-ARTERY ATHEROSCLEROSIS

Oxidation of low density lipoprotein (LDL) is implicated in the pathog enesis of atherosclerosis. In this study the susceptibility to oxidati on of LDL (from patients with antherosclerosis) is related to the prog ression of the disease, LDL were isolated from 37 patients with demons trable atherosclerotic plaques, The susceptibility of LDL to oxidation (induced by an exogenous oxidative stress) was assessed by measuring the breakdown products of lipid peroxidation, the increased formation of conjugated dienes, and changes in surface charge of the apolipoprot ein B (ape B). Progression of the atherosclerotic plaque was assessed by measuring the maximum velocity of blood through the narrowest porti on of the vessel at inclusion and after one year, Twenty-nine of the 3 7 samples taken were found to have LDL that were partially oxidised, w hereas 8 samples showed LDL whose state of oxidation was within the no rmal range, Progression of the atherosclerotic plaque occurred in 19 ( 66%) of the 29 patients whose lipoproteins were partially oxidised com pared with only 2 (25%) of the 8 patients with normal lipoproteins (P = 0.055, Fisher's exact test), These data support an association betwe en the progression of atherosclerotic plaques in carotid and femoral v essels and the susceptibility to oxidation of LDL.