Preemptive kidney transplantation: a propensity score matched cohort study.

Abstract

The reasons for improved outcomes associated with preemptive kidney transplantation (PKT) are incompletely understood, and post-transplant complications have been scarcely investigated. We evaluated the outcomes of PKT in both unmatched (n=1060) and propensity score matched cohorts (n=186) of adults who underwent living kidney transplant between 2000 and 2014. Outcomes were estimated glomerular filtration rate (eGFR), biopsy-proven rejection, cytomegalovirus (CMV) infection, post-transplant diabetes mellitus (PTDM), cardiovascular disease (CVD), graft failure (non-censored for death), and malignancy. Primary endpoint was post-transplant renal function assessed with eGFR. A total of 95 patients (9.0%) underwent PKT. The 2-week mean eGFR after transplant was comparable between the matched PKT and non-PKT groups (45.2 vs. 46.5mL/min/1.73m2, respectively, P=0.56). Sensitivity analysis using various formulas did not change the results. PKT was not superior to non-PKT in reducing the risk of biopsy-proven rejection, CMV, PTDM, and malignancy, regardless of matching. The risk of graft failure and CVD was significantly reduced in the unmatched PKT group (ARR, -6.2%; 95% CI, -8.6 to -0.7; P=0.03, and ARR, -6.7%; 95% CI, -9.6 to -0.7, P=0.03, respectively); nevertheless, the corresponding ARRs were -3.2% (95% CI, -10.0 to 2.9; P=0.44) and -2.2% (95% CI, -9.1 to 4.4; P=0.72) after matching. PKT was associated with neither improvement of post-transplant renal function nor a lower rate of common post-transplant complications than non-PKT among patients with end-stage renal disease who underwent living KT.