Kidney graft survival in Europe and the United States: strikingly different long-term outcomes.

Background: Kidney graft survival has never been systematically compared between Europe and the United States.
Methods: Applying period analysis to first deceased-donor (DD) and living-donor kidney grafts from the United Network for Organ Sharing/Organ Procurement and Transplantation Network for the United States and the Collaborative Transplant Study for Europe, we compared overall and age-specific 1-, 5-, and 10-year graft survival for Europeans and white, African, and Hispanic Americans for the 2005 to 2008 period. A Cox regression model was used to adjust for differences in patient characteristics.
Results: For the 2005 to 2008 period, 1-year survival for DD grafts was equal (91%) between Europeans and white and Hispanic Americans, whereas it was slightly lower for African Americans (89%). In contrast, overall 5- and 10-year graft survival rates were considerably higher for Europe (77 and 56%, respectively) than for any of the three U.S. populations (whites, 71 and 46%, Hispanic, 73 and 48%, and African American, 62 and 34%). Differences were largest for recipient ages 0 to 17 and 18 to 29 and generally increased beyond 3 to 4 years after transplantation. Survival patterns for living-donor grafts were similar as those seen for DD grafts. Adjusted hazard ratios for graft failure in United Network for Organ Sharing white Americans ranged between 1.5 and 2.3 (all P<0.001) for 2 to 5 years after transplantation, indicating that lower graft survival is not explained by differences in baseline patient characteristics.
Conclusions: Long-term kidney graft survival rates are markedly lower in the United States compared with Europe. Identifying actionable factors explaining long-term graft survival differences between Europe and the United States is a high priority for improving long-term graft survival.