APOLIPOPROTEIN(A) PHENOTYPES PREDICT THE RISK FOR CAROTID ATHEROSCLEROSIS IN PATIENTS WITH END-STAGE RENAL-DISEASE

Several studies have demonstrated that atherosclerotic complications a re the major cause of morbidity and mortality in hemodialysis patients . High lipoprotein(a) [Lp(a)] plasma concentrations are an independent risk factor for atherosclerosis. Patients with end-stage renal diseas e (ESRD) have elevated plasma concentrations of Lp(a), which are not e xplained by size variation at the apolipoprotein(a) [apo(a)] gene locu s. The aim of our study was to investigate whether Lp(a) concentration s and/or apo(a) phenotypes are predictive of the degree of atheroscler osis in the extracranial carotid arteries in ESRD patients. Of 167 pat ients, 108 showed atherosclerotic plaques (65%). Univariate analysis s howed that the plaque-affected group was significantly older and had a higher frequency of angina pectoris, previous myocardial infarction, or cerebrovascular accident. Furthermore, this group included signific antly more patients with low-molecular-weight apo(a) isoforms (26.9% v ersus 8.5%, P < .005) and had significantly higher mean Lp(a) plasma c oncentrations (29.3 +/- 31.0 versus 19.7 +/- 25.7 mg/dL, P < .05). Lp( a) plasma concentration increased significantly with the number of aff ected arterial sites, from 19.7 mg/dL in patients without plaques to 4 0.1 mg/dL in patients with seven or eight affected sites. In patients with low-molecular-weight phenotypes, significantly more arterial site s were affected (3.62 versus 2.08,. P < .001). Multivariate regression analysis showed that age, angina pectoris, and the apo(a) phenotype w ere the only significant predictors of the degree of atherosclerosis. We conclude that, besides age, the apo(a) phenotype is the best predic tor of carotid atherosclerosis in ESRD patients and may be used for as sessment of general atherosclerosis in this patient group.