Fareed Kamar1, Robert R Quinn2, Matthew J Oliver3, Andrea K Viecelli4, Swapnil Hiremath5, Jennifer MacRae6, Lisa Miller7, Peter Blake8, Louise Moist8, Amit X Garg9, Ngan N Lam10, Rameez Kabani1, Alix Clarke1, Ping Liu11, Brenda Gillespie12, Pietro Ravani13. 1. Department of Medicine, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada. 2. Department of Medicine, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada; Department of Community Health Sciences, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada. 3. Department of Medicine, University of Toronto, Toronto, ON, Canada. 4. School of Medicine, University of Queensland, Brisbane, Queensland, Australia; Department of Nephrology, Princess Alexandra Hospital, Brisbane, Queensland, Australia. 5. Division of Nephrology, Department of Medicine and Kidney Research Centre, Ottawa Hospital Research Institute, The University of Ottawa, Ottawa, ON, Canada. 6. Department of Medicine, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada; Department of Cardiac Sciences, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada. 7. Division of Nephrology, Department of Medicine, University of Manitoba, Winnipeg, MB, Canada. 8. Kidney Clinical Research Unit, London Health Sciences Centre, London, ON, Canada; Division of Nephrology, Department of Medicine, Western University, London, ON, Canada. 9. Kidney Clinical Research Unit, London Health Sciences Centre, London, ON, Canada; Division of Nephrology, Department of Medicine, Western University, London, ON, Canada; Institute for Clinical Evaluative Sciences, ON, Canada. 10. University of Alberta, Edmonton, AB, Canada. 11. Department of Community Health Sciences, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada. 12. Department of Biostatistics, School of Public Health, University of Michigan, Ann Arbor, MI. 13. Department of Medicine, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada; Department of Community Health Sciences, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada. Electronic address: pravani@ucalgary.ca.
Abstract
RATIONALE & OBJECTIVE: Fistulas are the preferred form of hemodialysis access; however, many fistulas fail to mature into usable accesses after creation. Data for outcomes after placement of a second fistula are limited. STUDY DESIGN: Cohort study. SETTING & PARTICIPANTS: People who initiated hemodialysis therapy in any of 5 Canadian dialysis programs (2004-2012) and had at least 1 hemodialysis fistula placed. PREDICTOR: Second versus initial fistula; receipt of 2 versus 1 fistula; second versus first fistula in recipients of 2 fistulas. OUTCOMES: Catheter-free fistula use during 1 year following initiation of hemodialysis therapy or following fistula creation, if created after hemodialysis therapy start; proportion of time with catheter-free use; time to catheter free use; time of functional patency. ANALYTICAL APPROACH: Logistic regression; fractional regression. RESULTS: Among the 1,091 study participants (mean age, 64±15 [SD] years; 63% men; 59% with diabetes), 901 received 1 and 190 received 2 fistulas. 38% of second fistulas versus 46% of first fistulas were used catheter free at least once. 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 people who received 1 fistula, those who received 2 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). Among people who received 2 fistulas, the proportion of time that the second fistula was used catheter free was 11% higher with each 10% greater proportion of time that the first fistula was used catheter free (95% CI, 1%-22%). Model discrimination was modest (C index, 0.69). LIMITATIONS: Unknown criteria for patient selection for 1 or 2 fistulas; unknown reasons for prolonged catheter use. CONCLUSIONS: Outcomes of a second fistula may be inferior to outcomes of the initial fistula. First and second fistula outcomes are weakly correlated and difficult to predict based on clinical characteristics.
RATIONALE & OBJECTIVE: Fistulas are the preferred form of hemodialysis access; however, many fistulas fail to mature into usable accesses after creation. Data for outcomes after placement of a second fistula are limited. STUDY DESIGN: Cohort study. SETTING & PARTICIPANTS: People who initiated hemodialysis therapy in any of 5 Canadian dialysis programs (2004-2012) and had at least 1 hemodialysis fistula placed. PREDICTOR: Second versus initial fistula; receipt of 2 versus 1 fistula; second versus first fistula in recipients of 2 fistulas. OUTCOMES: Catheter-free fistula use during 1 year following initiation of hemodialysis therapy or following fistula creation, if created after hemodialysis therapy start; proportion of time with catheter-free use; time to catheter free use; time of functional patency. ANALYTICAL APPROACH: Logistic regression; fractional regression. RESULTS: Among the 1,091 study participants (mean age, 64±15 [SD] years; 63% men; 59% with diabetes), 901 received 1 and 190 received 2 fistulas. 38% of second fistulas versus 46% of first fistulas were used catheter free at least once. 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 people who received 1 fistula, those who received 2 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). Among people who received 2 fistulas, the proportion of time that the second fistula was used catheter free was 11% higher with each 10% greater proportion of time that the first fistula was used catheter free (95% CI, 1%-22%). Model discrimination was modest (C index, 0.69). LIMITATIONS: Unknown criteria for patient selection for 1 or 2 fistulas; unknown reasons for prolonged catheter use. CONCLUSIONS: Outcomes of a second fistula may be inferior to outcomes of the initial fistula. First and second fistula outcomes are weakly correlated and difficult to predict based on clinical characteristics.
Authors: Todd Robinson; Randolph L Geary; Ross P Davis; Justin B Hurie; Timothy K Williams; Gabriella Velazquez-Ramirez; Shahriar Moossavi; Haiying Chen; Mariana Murea Journal: Kidney Med Date: 2021-02-10