Massicotte-Azarniouch David, Sood Manish M, Fergusson Dean A, Chassé Michaël, Tinmouth Alan, Knoll Greg A
Department of Medicine, University of Ottawa, Ontario, Canada.
Division of Nephrology, Kidney Research Center, Department of Medicine, University of Ottawa, Ontario, Canada.
Kidney Int Rep. 2021 Feb 2;6(4):1041-1049. doi: 10.1016/j.ekir.2021.01.015. eCollection 2021 Apr.
The impact of posttransplant red blood cell transfusion (RBCT) and their potential immunomodulatory effects on kidney transplant recipients are unclear. We examined the risks for adverse graft outcomes associated with post-kidney transplant RBCT.
We conducted a retrospective cohort study of all adult kidney transplant recipients at The Ottawa Hospital from 2002 to 2018. The exposure of interest was receipt of an RBCT after transplant categorized as 1, 2, 3 to 5, and >5 RBC. Outcomes of interest were rejection and death-censored graft loss (DCGL). Cox proportional hazards models were used to calculate hazard ratios (HR) with RBCT as a time-varying, cumulative exposure.
Among 1258 kidney transplant recipients, 468 (37.2%) received 2373 total RBCTs, 197 (15.7%) had rejection and 114 (9.1%) DCGL. For the receipt of 1, 2, 3 to 5, and >5 RBCT, compared with individuals never transfused, the adjusted HRs (95% confidence interval [CI]) for rejection were 2.47 (1.62-3.77), 1.27 (0.77-2.11), 1.74 (1.00-3.05), and 2.23 (1.13-4.40), respectively; DCGL 2.32 (1.02-5.27), 3.03 (1.62-5.64), 7.50 (4.19-13.43), and 14.63 (8.32-25.72), respectively. Considering a time-lag for an RBCT to be considered an exposure before an outcome to limit reverse causation, RBCT was not associated with rejection; the HRs for DCGL attenuated but remained similar. RBCT was also associated with a negative control outcome, demonstrating possible unmeasured confounding.
RBCT after kidney transplant is not associated with rejection, but may carry an increased risk for DCGL.
肾移植后红细胞输血（RBCT）的影响及其对肾移植受者潜在的免疫调节作用尚不清楚。我们研究了肾移植后RBCT与不良移植结局的风险。
我们对2002年至2018年渥太华医院所有成年肾移植受者进行了一项回顾性队列研究。感兴趣的暴露因素是移植后接受RBCT，分为1次、2次、3至5次和超过5次红细胞输血。感兴趣的结局是排斥反应和死亡删失的移植失功（DCGL）。使用Cox比例风险模型计算风险比（HR），将RBCT作为随时间变化的累积暴露因素。
在1258例肾移植受者中，468例（37.2%）共接受了2373次RBCT，197例（15.7%）发生排斥反应，114例（9.1%）发生DCGL。对于接受1次、2次、3至5次和超过5次RBCT的患者，与从未输血的个体相比，调整后的排斥反应HR（95%置信区间[CI]）分别为2.47（1.62-3.77）、1.27（0.77-2.11）、1.74（1.00-3.05）和2.23（1.13-4.40）；DCGL的HR分别为2.32（1.02-5.27）、3.03（1.62-5.64）、7.50（4.19-13.43）和14.63（8.32-25.72）。考虑到在结局发生前将RBCT视为暴露因素的时间滞后以限制反向因果关系，RBCT与排斥反应无关；DCGL的HR有所降低但仍相似。RBCT还与一个阴性对照结局相关，表明可能存在未测量的混杂因素。
肾移植后RBCT与排斥反应无关，但可能增加DCGL的风险。
