ASSOCIATION OF ATHEROGENIC LOW-DENSITY-LIPOPROTEIN SUBFRACTIONS WITH CAROTID ATHEROSCLEROSIS

Patients with carotid atherosclerosis are at increased risk of both st roke and ischaemic heart disease. Low-density lipoprotein (LDL) is a h eterogeneous group of particles, with small, dense particles being mor e atherogenic. We studied 79 patients (51 men, mean+/-SD age 62.4+/-11 .7 years) referred for Doppler ultrasound assessment of the carotid ar teries. Evidence of carotid atherosclerosis, defined as the presence o f atherosclerotic plaque, stenosis or occlusion in one or more of the six carotid artery segments examined, was found in 44 patients (56%). LDL subfractions were analysed by disc polyacrylamide gel electrophore sis with prior ultracentrifugation of serum to remove chylomicrons. Th is method produces a LDL score; the higher the score, the greater the proportion of the more atherogenic LDL subfractions. Mean LDL score wa s significantly higher in diseased patients (mean +/- SD, 1.56 +/- 0.6 1) than the normal group (1.26+/-0.65) (t=2.12, p = 0.037). There was no significant association between LDL score and severity of carotid a rtery stenosis. Age (adjusted odds Patio 1.09, 95%CI 1.03-1.15) and sm oking history (2.09, 95%CI 1.10-3.98) predicted carotid atherosclerosi s in logistic regression analysis, with LDL score achieving borderline significance (2.20, 95%CI 0.91-5.29), Small, dense LDL subfractions a re associated with carotid atherosclerosis and may be a modifiable ris k factor for stroke as well as ischaemic heart disease.