Permanent detrimental effect of nonimmunological factors on long-term renal graft survival: a parsimonious model of time-dependency.
OBJECTIVE
We attempted to model and test the pattern of effects of prognostic factors on renal graft survival during the posttransplantation time course.


METHODS
Patients who received a cadaveric kidney-only transplant between January 1990 and December 1995 in Eurotransplant, who received cyclosporine as induction therapy, and who had a complete follow-up at the time of analysis were included in the study (n= 10614). An index summarizing all covariate information was calculated and used for modeling the time-dependent effects with relation to graft failure.


RESULTS
The immunological factors (HLA mismatch and % panel-reactive antibody) were seen to have a slowly decreasing negative effect on renal graft survival. The cold ischemic trauma (>24 hr) exerted a permanent detrimental effect on the grafts. The use of organs obtained from old donors was associated with a constant higher risk of graft loss.


CONCLUSIONS
An analysis of determinants of human allograft dysfunction should also study the interaction between the effects and time. Nonimmunological factors had a constant detrimental effect on graft failure, whereas the impact of the immunological factors--although remaining important for late graft loss--very slowly decreased. In the context of marginal transplants, clustering of unfavorable factors should be avoided to prevent late graft losses.
Smits
J M
JM
Eurotransplant International Foundation, Leiden, The Netherlands. JSMITS@eurotransplant.nl
van Houwelingen
H C
HC
De Meester
J
J
le Cessie
S
S
Persijn
G G
GG
Claas
F H
FH
Frei
U
U
D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D005260:Female; D006084:Graft Rejection / Q000517:prevention & control; D006085:Graft Survival / Q000502:physiology*; D006801:Humans; D007223:Infant; D016030:Kidney Transplantation / Q000276:immunology; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D016016:Proportional Hazards Models; D013997:Time Factors