A study reported that infants who underwent cardiac surgery for congenital heart defects are likely to develop behavior problems in later years due to apolipoprotein E (APOE) genotype.

The authors reported that previous studies showed the association of the APOE e2 allele with significantly worse neurodevelopmental outcomes at 1 year of age in children who underwent surgery for congenital heart disease as infants.

Dr. J. William Gaynor from Children’s Hospital of Philadelphia, and team investigated preschool-aged children (4-5 years of age) who underwent surgery at infant stage to find the effects of APOE polymorphisms on neurobehavioral outcomes.

The investigation showed that almost 30% of children had at least moderate cognitive impairment, 25% had at least moderate core language impairment, and executive function was moderately impaired in 33% and severely impaired in 11%.

The researchers reported that APOE e2 allele was significantly linked to worse problems in somatic complaints, pervasive developmental problems, and internalizing problems where as APOE e4 was associated with better outcomes in these areas.

There were impaired social skills associated with APOE e2 carriers compared with e4 carriers.

The investigators said that APOE e2 group head circumference was significantly smaller, which suggests impaired postnatal brain growth.

The study demonstrates that the APOE e2 allele is associated with increased behavior problems at 4 years of age, which confirms our previous report that the e2 allele is associated with worse neurodevelopmental outcomes at 1 year of age after repair of congenital heart defects in infancy, the authors conclude.

This APOE genotype-environment interaction demonstrates that genetic polymorphisms that impair neuroresiliency and CNS recovery may explain some of the inter-individual variation in developmental outcomes after surgery for treatment of congenital heart defects.