LIPOPROTEIN(A) AS A DETERMINANT OF THE SEVERITY OF ANGIOGRAPHICALLY DEFINED CAROTID ATHEROSCLEROSIS

We measured fasting serum lipids, lipoproteins, apolipoproteins and li poprotein(a) [Lp(a)] in 49 Caucasian patients with transient ischaemic attacks undergoing carotid angiography. The severity of extracranial cerebrovascular disease was assessed visually by a highly reproducible grading system that focused on the internal carotid artery and caroti d bifurcation. Compared with a healthy reference group, patients had s ignificantly higher serum concentrations of: total cholesterol (mean+/ -SD), 6.2+/-1.6 vs. 5.6+/-1.0 mmol/l, p=0.02; apolipoprotein B, 1.4+/- 0.5 vs. 1.2+/-0.3 g/l, p=0.03; triglyceride [geometric mean(95% CI)], 2.02(1.75-2.32) vs. 1.66(0.67-4.06) mmol/l, p=0.03; and l-p(a), 0.33(0 .26-0.42) vs. 0.17(0.40-0.76) g/l, p<0.001. Regression analysis showed that of the lipoprotein-related variables, only Lp(a) was significant ly related to the severity of carotid artery disease (p=0.04) in the p atients; this association remained significant after adjusting for age , sex, blood pressure, and a history of stroke. Serum Lp(a) concentrat ion was significantly higher in patients with carotid artery disease s everity score above the median value of the sample population compared with those below the median: 0.45 vs. 0.24 g/l (95% CI for difference 0.35-0.88), p=0.01. Elevated serum Lp(a) is a significant determinant of the extent of carotid atherosclerosis and may be useful in identif ying patients most at risk of stroke.