Excess Risk of Death Increases with Time from First Dialysis for Patients on the Waiting List: Implications for Renal Allograft Allocation Policy

Abstract

Background: Subgroups of patients registered on a kidney transplant waiting list have higher than usual mortality levels. This study used data from the French Renal Epidemiology and Information Network (REIN) Registry to quantify the impact over time of various comorbidities on the excess risk of death among patients on the waiting list. Methods: Lexis diagrams were used to analyze time since onset of end-stage renal disease and time since registration on the waiting list. The number of excess deaths was calculated by comparison with the number of expected deaths in the general population of the same age and sex. Results: During 45,013 person-years of follow-up, 7,224 patients died, 5,956 (82%) more than expected relative to the general population. There were 101 deaths among wait-listed dialysis patients, 76 more than expected. The excess risk of death increased by 45% per additional year on the waiting list (18-79%, p = 0.0005). Time from end-stage renal disease onset until list registration (p = 0.004), time since registration (p < 0.001), age >65 years (p = 0.008), the presence of a primary renal disease (p = 0.028), and the number of comorbidities (p = 0.035) were independent predictors of death while on the waiting list. Conclusions: The excess risk of death while on the waiting list increased faster in patients with comorbidities. These results require consideration of ways to accelerate access to transplantation in high-risk patients.