Center effect on posttransplant survival among currently active United States pediatric heart transplant centers

Abstract

The official analysis of posttransplant survival considers only recently transplanted patients and suggests absence of outcome differences among pediatric heart transplant (HT) centers. We sought to compare posttransplant survival among currently active pediatric HT centers in the United States over 15 years of activity. We identified all children <18 years old who underwent their first HT during 2000-2014 at US centers active during 2013-14. Recipients were followed until March 2016. A mixed-effects survival model with center as a random effect was used to assess center differences in patient and graft survival. Center case-mix and standardized mortality ratio (SMR) for 90-day mortality were assessed by applying an internally validated risk-model. Overall, 4271 children transplanted at 46 centers were analyzed. There was a significant center effect on risk-adjusted patient (P = .01) and graft survival (P < .001). Adjusting for 90-day SMR or center-volume, but not for case-mix, was associated with a significant reduction in center effect on long-term survival. There was no center effect on conditional survival in 90-day survivors. In conclusion, there are significant differences in posttransplant survival among pediatric HT centers in the United States. Centers with better short-term performance (lower SMR for 90-day mortality) maintain their outcome advantage on follow-up and have superior longer-term outcomes.

Keywords: clinical research/practice; graft survival; health services and outcomes research; heart transplantation/cardiology; patient survival; pediatrics.