Lipoprotein(a) and Vascular Access Survival in Patients on Chronic Hemodialysis

Abstract

Lipoprotein(a) [Lp(a)] is an independent risk factor for atherosclerotic and cardiovascular complications in the general population and in hemodialysis patients. Increased Lp(a) levels have been also described as a possible predictor of vascular access occlusion in patients on chronic hemodialysis. We have studied prospectively the relationship between vascular access survival and Lp(a) levels in 40 hemodialysis patients. The Lp(a) plasma concentrations were measured by enzyme-linked immunosorbent assay in all patients in April 1993. Throughout the following year, evolution and survival of their vascular accesses were analyzed. Failure of vascular access was established when there were complications requiring surgical repair or transluminal angioplasty. Fourteen patients showed failure of vascular access, and the cumulative survival of vascular accesses after 1 year of follow-up was 63.8%. The Lp(a) levels were higher in patients with failure of vascular access than in the others (35.2 +/- 31 vs. 22.4 +/- 25 md/dl), but this difference did not reach statistical significance (p = 0.064). The vascular access survival in patients with Lp(a) levels > 75th percentile (52.5 mg/dl) was significantly lower than in the remaining patients (40 vs. 72%; p = 0.045). This difference increased when we analyzed the patients with Lp(a) levels > 90th percentile (76 md/dl; 25 vs. 68%; p = 0.002). Our results suggest that patients with the highest levels of Lp(a) are at risk of developing complications in their vascular accesses, and they also have lower vascular access survival.