Association of HLA Mismatch With Death With a Functioning Graft After Kidney Transplantation: A Collaborative Transplant Study Report

HLA mismatches may correlate with risk of death with a functioning graft (DWFG) because of requirement for higher immunosuppression doses and more antirejection therapy. Deceased‐donor kidney transplants (n = 177 584) performed 1990–2009 and reported to the Collaborative Transplant Study were analyzed. The incidence of DWFG was found to be 4.8% during year 1 posttransplant and 7.7% during years 2–5 (Kaplan–Meier estimates). Most frequent causes of DWFG were infection, cardiovascular disease and malignancy (32.2%, 30.9% and 3.6% in year 1; 16.4%, 29.6% and 15.9% in years 2–5). HLA‐A + B + DR mismatches were significantly associated with DWFG during year 1 (p < 0.001), a correlation that diminished but persisted during years 2–5 (p < 0.001). HLA mismatch was associated with DWFG because of infection (p < 0.001 during year 1, p = 0.043 during years 2–5) or cardiovascular disease (p < 0.001 during year 1, p = 0.030 during years 2–5) but not malignancy. There was also a significant association between HLA mismatch and hospitalization for viral (p < 0.001) or bacterial (p = 0.002) infection. Multivariable analysis showed that mismatches for HLA class II were more strongly associated with both hospitalization and DWFG than mismatches for HLA class I.