Hemodialysis vascular access and clinical outcomes: an observational multicenter study.

Background: Arteriovenous fistula (AVF) is the optimal vascular access in hemodialysis (HD) patients because of its lower complication rates and better longevity compared to arteriovenous graft (AVG) and central venous catheter (CVC).
Methods: A cohort of 532 HD patients from nine HD facilities were recruited in September 2012 and prospectively followed for a median of 28 months. Unadjusted and fully adjusted hazard ratios (HR) of mortality for vascular access were calculated using Cox proportional hazards model.
Results: Seventy-two percent of patients had AVF, 7% AVG, 21% CVC. Overall, AVF failure was 43 per 1000 patient-years and AVF creation 19 per 1000 patient-years. In logistic regression analysis, odds ratio of having non-AVF access for age was 1.02 (95% CI: 1.01-1.03), female gender 1.97 (95% CI: 1.30-3.01), and Charlson comorbidity index (CCI) 1.17 (95% CI: 1.02-1.36). Total number of deaths was 17 per 100 patient-years. Two percent of death was because of pure catheter infection and 10.5% more mortality happened due to catheter infection complicated by underlying cardiovascular diseases. In unadjusted and full adjustment Cox models, HR of death for patients with CVC (reference: AVF patients) was, respectively, 2.17 (95% CI: 1.51-3.11) and 1.58 (95% CI: 1.01-2.51). Access problems of insertion-repair accounted for 24% of hospitalization, and catheter infection explained 10% of total admissions.
Conclusions: Catheter use in HD patients was associated with higher mortality and morbidity despite extensive adjustment for covariates. Risk factors for higher usage of non-AVF access are older age, female gender, and underlying comorbidities.