Background: The relationship between transplantation prior to chronic dialysis initiation and the pattern of acute rejection of kidneys from living donors (LDKT) has not been fully explored.
Methods: Using data provided by the United States Renal Data System, we performed a retrospective cohort study fitting multivariate proportional hazards models to characterize the association of chronic use of dialysis prior to transplantation [non-pre-emptive LDKT (non-PLDKT)] and acute rejection, and to examine if this association varies throughout the first year.
Results: Non-PLDKT was associated with a 2.5-fold higher rate of biopsy-confirmed rejection during the first month [adjusted HR 2.5, 95% confidence interval (1.85-3.33)], compared with no dialysis prior to transplantation. Increasing duration of pre-transplant dialysis was associated with increasing rate of biopsy-confirmed acute rejection during the first month (P = 0.001 for trend). Over the first year, there was a diminishing relationship between non-PLDKT and acute rejection: 2.5-, 2.22-, 2.13- and 1.78-fold elevation in the episodes of biopsy-confirmed acute rejection during the first, second, third through to the sixth and seventh through to the twelfth month post-transplant, respectively (P = 0.05 for trend).
Conclusions: The waning of the association of non-PLDKT with acute rejection over time supports the hypothesis that dialysis exposure prior to transplantation may modulate the immune system to increase the rates of acute rejection.