SS20 Mortality Benefits of Different Hemodialysis Access Types Are Age-Dependent

Abstract

Risk of death in dialysis patients is lowest with arteriovenous fistulas (AVFs), followed by arteriovenous grafts (AVGs) and then intravenous hemodialysis catheters (IHCs). Our aim was to analyze the effect of age on first dialysis access outcomes. All patients aged ≥18 years in the United States Renal Data System (2006-2010) were analyzed. Spline modeling and risk-adjusted Cox proportional hazard models were used to analyze the effect of age on mortality for first dialysis access with AVF vs AVG vs IHC. The study analyzed 502,380 patients (63 ± 15 years, 57% male, 41% mortality, followup 1.6 ± 1.4 years). Increasing age was a significant predictor of overall mortality (adjusted hazard ratio [HR], 1.03; P < .001). Compared with patients with IHC (N = 419,009), overall risk-adjusted mortality was lowest in patients with AVF (N = 71,328; HR, 0.65; P < .001), followed by AVG (N = 17,544; HR, 0.83; P < .001). AVF was superior to IHC and AVG for all age groups (P < .001; Fig 1). However, there was a significant change in the relative efficacy of AVG at age 45 based on spline modeling: there were no differences comparing AVG to IHC for patients aged 18 to 44 years (adjusted HR, 0.90; P = .12), but AVG was superior to IHC for patients aged ≥45 years (adjusted HR, 0.82; P < .001). Contrary to previous reports, our data suggest that AVF is superior to AVG and IHC regardless of patient age, including in octogenarians. In contrast, the mortality benefit of AVG over IHC may not apply to younger age groups. All patients aged <45 years should receive AVF for dialysis access whenever possible.