Effects of patient age on patency of chronic hemodialysis vascular access

BACKGROUND: In this single-center, retrospective observational study, we assessed the long-term patency of vascular access (VA) after first VA placement to uncover independent risk factors associated with VA patency in Asian hemodialysis (HD) patients stratified by age. We also investigated factors associated with VA patency among older HD patients according to the type of VA in the overall study population. METHODS: The study period was from January 2011 to December 2013. A total of 651 chronic HD patients with confirmed first upper-extremity VA placement were enrolled, and their records were analyzed retrospectively. A total of 445 patients (68.4%) made up the nonelderly group (< 65 years), and 206 patients (31.6%) were in the elderly group (≥ 65 years). Study outcomes were defined as primary or secondary VA patency. RESULTS: Autologous arteriovenous fistula (AVF) was more common in the nonelderly group (P < 0.01). Kaplan–Meier curve survival analysis indicated that primary patency was longer in the nonelderly group (P < 0.01); secondary patency, however, was similar between groups (P = 0.37). The multivariate analysis of factors associated with primary VA patency revealed that increased age (hazard ratio [HR], 1.02; 95% confidence interval [CI], 1.01–1.03; P < 0.01) was associated with shorter primary patency, and AVF (HR, 0.38; 95% CI, 0.28–0.51; P < 0.01) was associated with longer primary patency. AVF (HR, 0.57; 95% CI, 0.37–0.87; P = 0.010) and diabetes mellitus (HR, 1.56; 95% CI, 1.07–2.29; P = 0.02) were independently associated with longer and shorter secondary patency periods, respectively; however, increased age was not a risk factor for decreased secondary patency. CONCLUSIONS: Increased age was associated with shorter primary patency but not secondary patency, whereas AVF placement was associated with longer primary and secondary patency. Considering the similar rates of secondary patency between groups and the superior patency of AVF compared to arteriovenous graft, a fistula-first strategy should be applied to appropriate older patients.