Pre-kidney Donation Pregnancy Complications and Long-term Outcomes

Abstract

Background: Hypertension and diabetes are contraindications for living kidney donation in young candidates. However, little is known about the long-term outcomes of women who had these pregnancy-related complications and subsequently became donors. In the general population, gestational hypertension (GHtn), preeclampsia/eclampsia, and gestational diabetes (GDM) are associated with long-term risks.

Methods: Donors with the specified predonation complication were matched to contemporary control donors with pregnancies without the complication using nearest neighbor propensity score matching. Propensity scores were estimated using logistic regression with covariates for gravidity, blood pressure, glucose, body mass index, age, and creatinine at donation, donation year, race, relationship with recipient, and family history of disease. Long-term incidence of hypertension, diabetes, cardiovascular disease, and reduced renal function (estimated glomerular filtration rate [eGFR] <30, eGFR <45 mL/min/1.73 m 2 ) were compared between groups using proportional hazards models.

Results: Of 1862 donors with predonation pregnancies, 48 had preeclampsia/eclampsia, 49 had GHtn without preeclampsia, and 43 had GDM. Donors had a long interval between first pregnancy and donation (median, 18.5 y; interquartile range, 10.6-27.5) and a long postdonation follow-up time (median, 18.0; interquartile range, 9.2-27.7 y). GHtn was associated with the development of hypertension (hazard ratio, 1.89; 95% confidence interval, 1.26-2.83); GDM was associated with diabetes (hazard ratio, 3.04; 95% confidence interval, 1.33-6.99). Pregnancy complications were not associated with eGFR <30 or eGFR <45 mL/min/1.73 m 2 .

Conclusions: Our data suggest that women with predonation pregnancy-related complications have long-term risks even with a normal donor evaluation. Donor candidates with a history of pregnancy-related complications should be counseled about these risks.

Figure 1:

Overlap between pregnancy complications experienced (a) by the same donor across potentially multiple pregnancies, and (b) within the same pregnancy. If a donor was noted as experiencing both gestational hypertension and pre-eclampsia or eclampsia in a pregnancy they were classified as having pre-eclampsia or eclampsia in Figure 1a. Six individuals who were noted as having complications before donation, but with uncertain information about which pregnancies had the complication were excluded from Figure 1b.

Figure 2:. Postdonation disease free probability by predonation pregnancy complications. Kaplan Meier Curves with confidence intervals from 1 imputation.

Outcomes of donors with a given predonation pregnancy complication were compared to matched donors without the given complication. Donors may be classified into more than 1 predonation pregnancy complication category. Comp=Complication, PE/E=pre-eclampsia/eclampsia, gHTN= gestational hypertesion