Plasma concentration of von Willebrand factor predicts mortality in patients on chronic renal replacement therapy

Background. Traditional cardiovascular risk factors do not explain the high incidence of cardiovascular mortality and morbidity in patients with end-stage renal disease. A prothrombotic state could accelerate the process of vascular disease in these patients. Methods. In this study, four platelet activation markers (NAP-2, P-selectin, GP1b and RANTES) and two endothelial cell activation markers (von Willebrand factor and its propeptide) were measured in 671 haemodialysis patients and 275 patients on continuous ambulatory peritoneal dialysis (PD). All were long-term dialysis patients. The risk of all-cause and cardiovascular mortality was assessed in relation to these markers after a mean follow-up time of 2.5 years. Results. The von Willebrand factor showed a positive correlation with total mortality in the haemodialysis patients. In an unadjusted model, the hazard rate (HR) of total mortality was 2.4 [95% confidence interval (95% CI) 1.7-3.4] in the upper quartile of von Willebrand factor compared with the lowest quartile. It remained statistically significant (HR 1.8; 95% CI 1.2-2.6) after adjustment for traditional risk factors. In contrast, no significant correlation was found between von Willebrand factor levels and total mortality in PD patients. Finally, no relationship between platelet activation markers and total mortality was found in either the haemodialysis or the PD patients. Conclusion. It can be concluded that chronic endothelial cell activation, but not platelet activation, is related to all-cause mortality in end-stage renal disease patients on long-term dialysi