Different impact of hemodialysis vintage on cause-specific mortality in long-term hemodialysis patients

Abstract

Background. Although dialysis vintage is associated with increased mortality risk in patients receiving hemodialysis (HD), the association of dialysis vintage with cause-specific mortality is unclear. Methods. We conducted a nationwide registry-based retrospective cohort study of 216 246 patients receiving maintenance HD for >1 year at the end of 2009. The associations of dialysis vintage categories (1-<2, 2-<5, 5-<10, 10-<15, 15-<20, 20-<25, 25-<30 and ≥30 years) with 1-year allcause and cause-specific mortality, including cardiovascular diseases (CVDs) and infection-related mortality, were examined using logistic regression models. Results. During the 1-year study period, 18 614 deaths occurred from all causes, including 7263 and 3504 deaths from CVD and infection-related causes. From multivariate analysis, the dialysis vintage was incrementally associated with a higher risk for allcause mortality, with worse outcome observed in the ≥30 years category {odds ratio [OR] = 2.43 (95% confidence interval (CI) 2.13-2.77}. A similar association was apparent between the dialysis vintage and infection-related mortality, with a higher risk than that of all-cause mortality in each vintage category [≥30 years, OR = 3.55 (95% CI 2.72-4.66)], while the dialysis vintage was associated with only amodest increase in risk of CVDmortality [≥30 years, OR = 1.64 (95% CI 1.30-2.08)]. Conclusions. Dialysis vintage has a different impact on causespecific mortality, with a higher risk for infection-related mortality than CVD mortality. This impact is most pronounced in long-term HD survivors, to whom much attention should be devoted to prevent infectious complications.