PP106. Risk of long term renal graft loss after pregnancy in renal transplant recipients immunosuppressed with calcineurin inhibitors

Pregnancy Hypertens. 2012 Jul;2(3):297. doi: 10.1016/j.preghy.2012.04.217. Epub 2012 Jun 13.

Abstract

Introduction: Intron long-term graft function are uncertain. Although there have been a large number of successful pregnancies in renal graft recipients, the effects of pregnancy and type of immunosuppressant drugs.

Objectives: To analyze (1) the impact of pregnancy on the long term renal function and graft survival of kidney transplant recipients (KTx), and (2) the impact og the pregnancy in (KTx) immunosupressed with calcineurin inhibitors (CNI).

Methods: Retrospective analysis of two cohorts: one (PG) formed by all the KTx recipients from our institution that became pregnant between 1973 and 2004, and the other one (NPG) formed by, when possible, up two KTx patients of similar demographic and clinical characteristics: patient age, donor source, donor age, interval between KTx and pregnancy (or a matched interval for NPG), baseline renal function before pregnancy, hypertension, proteinuria >1g, and CNI-based immunosuppression. but without pregnancies. Particular attention has been paid to long-term (5 and 10years) renal function and graft survival. Males were selected to complete NPG if no matched women were available.

Statistical analysis: Assessment of baseline homogeneity between the two cohorts was performed by appropriate analysis. Time of survival of kidney was estimated by means Kaplan-Meier method and the Cox proportional hazard model was used to perform adjusted analysis.

Results: Fifty five pregnancies in 43 patients (PG) and 68 paired controls (NPG) were included in the study. The basal and functional characteristics of PG before pregnancy and NPG were not statistical and clinical significantly different. In a univariate Cox regression analysis, 10 years graft survival after pregnancy/study entry was significantly better in CG (79.9%) than PG (60.9%) (P=0.02). Multivariate analysis of graft survival showed an increased risk of long-term graft loss in pregnant women that had been treated with CNI as immunosuppressant drug compared with NP KTx that received CNIs (HR: 2.4, 95% CI, 1.17-5.00; P=0.02). In a stratified analysis, evaluating separately the recipients that had received or not CNIs, the risk of graft loss was only increased among recipients that became pregnant post-transplantation treated with CNI compared with recipients that had received CNIs but had not become pregnant (HR: 3.3, 95% CI, 1.42-7.45; P=0.005), but not among recipients that became pregnant post-transplantation and received other immunosuppressant agents (HR: 0.9, 95% CI, 0.24-3.80; P=0.94).

Conclusion: Pregnancy in women receiving baseline immunosuppression with CNI significantly increases the risk of long-term graft loss, non observed in KTx patients treated with CNI that not became pregnant, nor in KTx patients that became pregnant but are treated with other immunosuppressant drugs . At our knowledge, this observation has not been previously reported.