Impact of the serum bone-specific alkaline phosphatase level at the initiation of hemodialysis therapy for end-stage renal disease on cardiovascular events

Background: Patients with end-stage renal disease (ESRD) have high rates of hospitalization for cardiovascular (CV) events and short-term mortality after the initiation of hemodialysis (HD) therapy. To improve outcomes, it is important to identify predictive laboratory markers. We investigated whether the serum bone-specific alkaline phosphatase (BAP) level at the initiation of HD therapy for ESRD was associated with adverse events. Methods: This was a retrospective cohort study of 47 ESRD outpatients who were referred to our clinic for HD. The serum BAP level was measured within 1 month after the initiation of HD. Patients were divided into high-BAP and low-BAP groups according to the median serum BAP level (24.6 U/L). The impact of the serum BAP level on CV events (coronary artery disease, peripheral arterial disease, cerebrovascular disease, other CV events including aortic dissection, and mortality) was investigated. Results: During a median follow-up period of 72 months, CV events occurred in 14 patients (29.8%). Kaplan-Meier analysis showed that the disease-free and overall survival rates were lower in the high-BAP group than in the lowBAP group (p = 0.003 and p = 0.037, respectively, log-rank test). After adjustment for age, sex, and other confounding factors, Cox proportional hazards analysis found that the high-BAP group had a 5.9-fold higher rate of CV events than the low-BAP group (hazard ratio: 5.89; 95% confidence interval: 1.184-29.309; p = 0.030). Conclusions: The serum BAP level at the initiation of HD therapy for ESRD is a useful non-invasive biomarker for predicting CV events. (C) 2014 The Authors. Published by Elsevier Ireland Ltd. This is an open access article under the CC BY-NC-ND license.