Mortality from cancer is not increased in elderly kidney transplant recipients compared to the general population: a competing risk analysis

Background: The impact of cancer on death of elderly kidney transplant recipients has been extensively investigated, but with conflicting results. Unlike their younger counterparts, in elderly kidney transplant recipients cardiovascular and infectious disease may outweigh cancer in causing the patient's death. Methods: Using competing risk analysis on a large retrospective cohort of kidney transplant recipients, we estimated the cause-specific cumulative incidence and hazard of death in different age categories and calculated standardized mortality ratios (SMRs) to compare mortality rates with the general population. Results: Six thousand seven hundred eighty-nine kidney transplant recipients were followed-up for a median of 9 years. Ten years after transplantation, in transplant recipients aged 20-39, 40-59, and 60+, the cumulative incidence of cancer-related death was 0.6 (95% confidence interval [CI]: 0.3-1.0), 2.9 (2.3-3.6) and 5.3% (3.5-7.5), whereas the SMR was 9.1 (5.5-15.0), 2.0 (1.6-2.5), and 0.8 (0.6-1.0), respectively. At variance with young recipients, the hazard and the cumulative incidence of cardiovascular-related death in elderly recipients was well above that of cancer-related death. Conclusions: Relative to the general population, cancer-related death is increased in young but not in elderly kidney transplant recipients because of the more marked increased incidence of competing cause of death in the latter category.