DELAYED GRAFT FUNCTION - RISK-FACTORS AND IMPLICATIONS FOR RENAL-ALLOGRAFT SURVIVAL

Delayed graft function (DGF) may be associated with diminished kidney allograft survival. We studied. the risk factors that lead to nonimmed iate function of a renal allograft and the consequences of DGF on shor t- and long-term renal transplant survival. Data from the U.S. Renal D ata System were used to measure the relationships among cold ischemia time, delayed graft function, acute rejection, and graft survival in 3 7,216 primary cadaveric renal transplants (1985-1992). These relations hips were investigated using the unconditional logistic and Cox multiv ariate regression methods. Cold ischemia time was strongly associated with DGF, with a 23% increase in the risk of DGF for every 6 hr of col d ischemia (P<0.001). Acute transplant rejection occurred more frequen tly in grafts with delayed function (37% vs. 20%; odds ratio=2.25, P=0 .001). DGF was independently predictive of 5-year graft loss (relative risk=1.53, P<0.001). The presence of both early acute rejection and D GF portended a dismal 5-year graft survival rate of 35%. Zero-HLA mism atch conferred a 10-15% improvement in 1- and 5-year graft survival re gardless of early functional status of the allograft. However, the 5-y ear graft survival rate in HLA-mismatched kidneys without DGF was sign ificantly higher than that of zero-mismatched kidneys with DGF (63% vs . 51%; P<0.001). DGF independently portends a significant reduction in short- and long-term graft survival. Delayed function and early rejec tion episodes exerted an additive adverse effect on allograft survival . The deleterious impact of delayed function is comparatively more sev ere than that of poor HLA matching.