A Clinical Prediction Score to Guide Referral of Elderly Dialysis Patients for Kidney Transplant Evaluation

INTRODUCTION: Dialysis patients aged ≥70 years derive improved life expectancy through kidney transplantation compared with their waitlisted counterparts, but guidelines are not clear about how to identify appropriate transplantation candidates. We developed a clinical prediction score to identify elderly dialysis patients with expected 5-year survival appropriate for kidney transplantation (>5 years). METHODS: Incident dialysis patients in 2006–2009 aged ≥70 were identified from the United States Renal Data System database and divided into derivation and validation cohorts. Using the derivation cohort, candidate variables with a significant crude association with 5-year all-cause mortality were included in a multivariable logistic regression model to generate a scoring system. The scoring system was tested in the validation cohort and a cohort of elderly transplant recipients. RESULTS: Characteristics most predictive of 5-year mortality included age >80, body mass index <18, the presence of congestive heart failure, chronic obstructive pulmonary disease, immobility, and being institutionalized. Factors associated with increased 5-year survival were non-white race, a primary cause of end-stage renal disease other than diabetes, employment within 6 months of dialysis initiation, and dialysis start via arteriovenous fistula. Five-year mortality was 47% for the lowest risk score group (3.6% of the validation cohort) and >90% for the highest risk cohort (42% of the validation cohort). DISCUSSION: This clinical prediction score could be useful for physicians to identify potentially suitable candidates for kidney transplantation.