Scientific Publications Database

Article Title: The Influence of Age on the Likelihood of Catheter-Free Fistula Use in Hemodialysis Patients
Authors: Ladak, Farah; Ravani, Pietro; Oliver, Matthew J.; Kamar, Fareed; Clarke, Alix; Hiremath, Swapnil; MacRae, Jennifer; Blake, Peter; Moist, Louise M.; Garg, Amit X.; Lam, Ngan; Dumaine, Chance; Quinn, Robert R.
Journal: CANADIAN JOURNAL OF KIDNEY HEALTH AND DISEASE Volume 6
Date of Publication:2019
Abstract:
Background: Clinical practice guidelines recommend arteriovenous fistulas as the preferred form of vascular access for hemodialysis. However, some studies have suggested that older age is associated with poorer fistula outcomes.Objective: We assessed the impact of age on the outcomes of fistula creation and access-related procedures.Design: This was a prospective cohort study using data collected as part of the Dialysis Measurement Analysis and Reporting (DMAR) system.Setting: Participating Canadian dialysis programs, including Southern Alberta Renal Program, Manitoba Renal Program, Sunnybrook Health Sciences Centre (Toronto, Ontario), London Health Sciences Centre (London, Ontario), and The Ottawa Hospital (Ottawa, Ontario).Patients: Incident hemodialysis patients aged 18 years and older who started dialysis between January 1, 2004, and May 31, 2012.Measurements: The primary outcome was the proportion of all first fistula attempts that resulted in catheter-free fistula use, defined as independent use of a fistula for hemodialysis (ie, no catheter in place). Secondary outcomes included the time to catheter-free fistula use among patients with a fistula creation attempt, total number of days of catheter-free fistula use, and the proportion of a patient's hemodialysis career spent with an independently functioning fistula (ie, catheter-free fistula use).Methods: We compared patient characteristics by age group, using t tests or Wilcoxon rank sum tests, and chi-square or Fisher exact tests, as appropriate. Logistic and fractional logistic regression were used to estimate the odds of achieving catheter-free fistula use by age group and the proportion of dialysis time spent catheter-free, respectively.Results: A total of 1091 patients met our inclusion criteria (567 age >= 65; 524 age < 65). Only 57% of first fistula attempts resulted in catheter-free fistula use irrespective of age (adjusted odds ratio [OR]>= (65vs) < (65) : 1.01; P= .93). The median time from hemodialysis start to catheter-free use of the first fistula did not differ by age when grouped into fistulas attempted pre- and post-dialysis initiation. The adjusted rates of access-related procedures were comparable (incidence rate ratio [IRR]>=(65vs) <65: 0.95; P =.32). The median percentage of follow-up time spent catheter-free was similar and low in patients who attempted fistulas (<65 years: 19% vs >= 65 years: 21%; P =.85).Limitations: The relatively short follow-up time may have underestimated the benefits of fistula creation and the observational study design precludes inferences about causality.Conclusions: In our study, older patients who underwent a fistula attempt were just as likely as younger patients to achieve catheter-free fistula use, within a similar time frame, and while requiring a similar number of access procedures. However, the minority of dialysis time was spent catheter-free.