Dialysis and Survival in Advanced CKD

Background: The decision to initiate dialysis in advanced, but stable, chronic kidney disease is difficult to navigate and can benefit from population level data on longevity. Methods: We evaluated dialysis-naïve subjects with estimated glomerular filtration rate (eGFR) < 15 mL/min/1.73m2 on at least 2 occasions between 90 and 365 days apart (n = 86,293). Individuals initiating dialysis (cases) were matched with those not initiating dialysis (controls) on the same day and with the same baseline propensity to start dialysis, with survival evaluated from that day forward. Results: In our study population, 48.5% were ≥ 70 years and the eGFR distribution was <5 mL/min/1.73m2 (5.7%), 5.0-9.9 (28.3%) and 10-14.9 (66.1%). Approximately half (45.4%) of the study population began maintenance dialysis after a median follow-up of 1.7 years. Overall median survival times were 2.89 (CI [95% confidence interval] 2.66-3.16) years in cases and 1.26 (CI 1.20-1.32) years in controls (hazards ratio 0.68 [0.63-0.73], P-Value < 0.001). Initiating dialysis was associated with an increase in median survival of 1.63 (CI 1.40-1.90) years. Dialysis-associated survival increments were 3.15 (CI 2.28-5.36) years with eGFR < 5, 1.64 (CI 1.11-2.10) years with eGFR 5 to 9.9, and 1.55 (CI 1.24-1.90) years with eGFR 10 to 14.9 mL/min/1.73m2. Dialysis was associated with positive survival increments in all age groups except those ≥ 90 years. Conclusion: In a population with eGFR chronically below 15 mL/min/1.73m2, dialysis was associated with meaningful survival increases. Funding: Veterans Affairs Support