Using Relative Survival to Estimate the Burden of Kidney Failure

Rationale & Objective: Estimates of mortality from kidney failure are misleading because the mortality from kidney failure is inseparable from the mortality attributed to comorbid conditions. We sought to develop an alternative method to reduce the bias in estimating mortality due to kidney failure using life table methods. Study Design: Longitudinal cohort study. Setting & Participants: Using data from the US Renal Data System and the Medicare 5% sample, we identified an incident cohort of patients, age 66+, who first had kidney failure in 2009 and a similar general population cohort without kidney failure. Exposure: Kidney failure. Outcome: Death. Analytical Approach: We created comorbidity, age, sex, race, and year-specific life tables to estimate relative survival of patients with incident kidney failure and to attain an estimate of excess kidney failure-related deaths. Estimates were compared with those based on standard life tables (not adjusted comorbidity). Results: The analysis included 31,944 adults kidney failure with a mean age of 77 +/- 7 years. 5-year relative survival was 31% using standard life tables (adjusted for age, sex, race, and versus 36% using life tables also adjusted comorbidities. Compared with other diseases, patients with kidney failure have the lowest relative survival. Patients with kidney failure ages 66-70 and 76-80 survival comparable to adults without kidney roughly 86-90 and 91-95 years old, respectively. Limitations: Relative survival estimates improved by narrowing the specificity covariates collected (eg, disease severity ethnicity). Conclusions: Estimates of survival relative matched general population partition the mortality due to kidney failure from other causes of Results highlight the immense burden of failure on mortality and the importance of prevention efforts among older adults.