Survival Benefits of Deceased Donor Kidney Transplant vs Waitlisting.

Importance: Deceased donor kidney transplant is the preferred treatment for people with kidney failure, but survival benefits are likely to vary by donor quality and recipient characteristics. Prior studies may have overestimated these benefits due to immortal time bias. Objective: To estimate the survival benefits of deceased donor kidney transplant compared with remaining on the waitlist. Design, Setting, and Participants: This population-based cohort study used a clone-censor-weight approach to emulate a randomized clinical trial with data from the Australia and New Zealand Dialysis and Transplant Registry (January 1, 2010, to December 31, 2021). Data analysis was conducted from January 2025 to April 2025. Patients waitlisted in Australia were categorized into 3 groups: (1) transplant from kidneys with low Kidney Donor Risk Index (KDRI) scores less than the 90th percentile, (2) transplant from kidneys with a high KDRI score equal to or greater than the 90th percentile, and (3) those waitlisted while receiving dialysis only (never received a transplant). Main Outcomes and Measures: The primary outcome was all-cause mortality. The 10-year risk differences, risk ratios, and restricted mean survival time differences were estimated from inverse probability-weighted pooled logistic regression. Results: Among 8011 patients who were waitlisted (median [IQR] age, 53.0 [42.0-62.0] years; 2902 [36.2%] were female), the estimated 10-year all-cause mortality was 22.4% (95% CI, 20.8%-24.2%) for the low KDRI group, 30.6% (95% CI, 24.8%-37.2%) for the high KDRI group, and 39.1% (95% CI, 33.2%-45.1%) for waitlisted patients. Compared with waitlisting, mean survival gains were 6.6 months (95% CI, 4.4-8.7) for kidneys with a low KDRI score and 3.6 months (95% CI, 0.3-6.4) for kidneys with a high KDRI score. Benefits were greatest for older recipients (≥60 years) who received low KDRI-scoring kidneys, showing a 35.8% reduction in mortality risk (95% CI, -50.2% to -21.0%). No survival benefit was observed in younger recipients (<60 years) who received high KDRI-scoring kidneys. Conclusions and Relevance: The results of this cohort study suggest that deceased donor kidney transplant is associated with improved survival compared with dialysis, but survival benefits vary by donor quality and recipient characteristics. High KDRI-scoring kidneys are associated with modest survival gains, with limited survival benefits observed among younger recipients. These findings highlight the need for tailored counseling and shared decision-making to align treatment choices with individual risks and expected outcomes.