Intellectual performance of kidney transplant recipients' offspring: a cross-sectional, multicenter study

The number of successful pregnancies in kidney transplant (KT) recipients has increased in recent years. Little evidence is available about the risk of in utero immunosuppressive exposure for long-term cognitive consequences. The aim of this study was to evaluate the impact of immunosuppression during pregnancy on intellectual performance of children born to KT recipients.

Using a cross-sectional design, women who had undergone KT and their children (aged 4+ years) were recruited at the outpatient follow-up in five transplant centers. Women who did not receive immunosuppression during pregnancy with similar distributions of socioeconomic status and length of gestation and their children were also recruited. Children were assessed with Wechsler Intelligence Scales.

The study sample included 50 exposed and 50 unexposed children. No differences between groups in all the proposed confounding factors were found. Full-scale IQ did not differ significantly between both groups. Also, significant differences in any index or subscale score were not observed, with the exception of time required to complete the Wechsler preschool and primary scale of intelligence (WPPSI) Zoo locations subtest, which was done quicker in the unexposed group (p = .007). Exposure to immunosuppression during pregnancy was not a significant predictor of low IQ in logistic regression after adjustment for other factors.

Immunosuppression therapy during pregnancy of KT women did not affect global intellectual performance of their offspring, except maybe for visuospatial working memory in preschool children.