Inferior outcomes after second hemodialysis fistula?
Nephrologists worldwide agree that fistulas are the preferred form of hemodialysis access.
The problem with this access is, however, well known: Quite a high proportion of fistulas fail to mature into usable accesses after creation. And, say the authors of the present joint US /Australian/Canadian study, there are only sparse data regarding the outcomes after the placement of a second fistula (Kamar F et al, Outcomes of the First and Second Hemodialysis Fistula: A Cohort Study; Am J Kidney Dis 2018; doi: 10.1053/j.ajkd.2018.06.007). The data from the present study show that a second fistula might lead to inferior outcomes vs. the first one.
The authors analyzed the data of approximately 1,100 patients (mean age 64 years) who initiated hemodialysis therapy and had at least one hemodialysis fistula placed. Outcomes included catheter-free fistula use during one year following initiation of hemodialysis therapy or following fistula creation, if fistula was created after hemodialysis therapy start. Also included as outcomes were the proportion of time with catheter-free use, time to catheter free use, and time of functional patency.
The vast majority of the patients (n=901) received one fistula, 190 patients received two fistulas. 38% of second fistulas were used catheter free at least once, versus 46% of first fistulas. The average percentages of time that second and initial fistulas were used catheter free were 34% and 42%, respectively (OR, 0.72; 95% CI, 0.54-0.94). Compared with persons who received one fistula, patients with two fistulas were less likely to achieve catheter-free use (26% vs. 56%) and remain catheter free (23% vs. 49% of time; OR, 0.30, 95% CI, 0.24-0.39). Patients with two fistulas had an 11% higher proportion of time that the second fistula was used catheter free, with each 10% greater proportion of time that the first fistula was used catheter free (95% CI, 1%-22%).
The authors conclude that outcomes of a second fistula are possibly inferior to outcomes of the initial fistula. In general, both first and second fistula outcomes are difficult to predict based on clinical characteristics.
Link to the study: https://www.ajkd.org/article/S0272-6386(18)30792-3/fulltext