Prematurity is a significant independent risk factor for adverse cognitive and motor outcomes in children with congenital heart disease, especially in those born at or before 33 weeks gestational age.
Key Findings
Results
Children with CHD born at or before 33 weeks gestational age had significantly lower cognitive and motor composite scores compared to those born at term.
Age-adjusted cognitive composite scores were 11 points lower (95% CI, 5-17) in children born ≤33 weeks compared to term/postterm infants.
Age-adjusted motor composite scores were 15 points lower (95% CI, 8-22) in children born ≤33 weeks compared to term/postterm infants.
These differences remained significant after multivariable adjustment for demographic, medical, and surgical covariates.
Gestational age was stratified into four groups: extremely/very/moderately preterm (≤33 weeks), late-preterm (34-36 weeks), early-term (37-38 weeks), and term/postterm (≥39 weeks).
Methods
Among 1350 infants who underwent cardiac surgery in infancy, 513 (38%) completed Bayley scale neurodevelopmental assessment.
Neurodevelopmental testing was completed at a median age of 28 months (interquartile range, 19-34).
Of the 513 children assessed, 448 (87%) were full term and 65 (13%) were preterm.
The study was a single-center retrospective cohort including children who underwent cardiac surgery between 2007 and 2020.
Neurodevelopmental outcomes were measured using the Bayley Scales of Infant and Toddler Development, Third Edition, assessing cognitive, language, and motor domains.
Results
Gestational age was a significant independent predictor of cognitive and motor Bayley scores after multivariable adjustment.
Multivariable linear regression was used to model Bayley scores, adjusting for demographic, medical, and surgical covariates.
Gestational age remained a significant predictor specifically for cognitive and motor composite scores.
Language scores were not reported as significantly predicted by gestational age in the multivariable model.
The models explained 17% to 26% of the variance in Bayley scores, with the highest explained variance in the motor domain.
Results
Several other factors beyond gestational age were significant independent predictors of worse neurodevelopmental outcomes in children with CHD.
Lower caregiver education was identified as a significant predictor of worse Bayley scores.
Black race was identified as a significant predictor of worse Bayley scores.
Longer hospitalization was identified as a significant predictor of worse Bayley scores.
Genetic diagnosis was identified as a significant predictor of worse Bayley scores.
Results
The multivariable models explained between 17% and 26% of the variance in Bayley scores, with motor outcomes having the highest explained variance.
Explained variance ranged from 17% to 26% across the three Bayley domains (cognitive, language, motor).
The motor domain had the highest proportion of variance explained by the model.
The relatively modest explained variance indicates that many factors contributing to neurodevelopmental outcomes in CHD remain unaccounted for.
Conclusions
The authors conclude that enhanced neurodevelopmental surveillance and targeted early intervention strategies are warranted for preterm infants with CHD.
Preterm infants with CHD may experience a 'double hit,' with worse neurodevelopmental impairments than seen in prematurity or CHD alone.
The study identifies preterm infants with CHD, particularly those born ≤33 weeks, as a especially vulnerable population.
The authors specifically call for enhanced neurodevelopmental surveillance and targeted early intervention strategies for this group.
What This Means
This research suggests that babies born prematurely who also have congenital heart disease (a structural problem with the heart present at birth) face compounded risks for developmental delays. The study followed 513 children who had heart surgery in infancy and were later tested for cognitive (thinking), language, and motor (movement) skills at around 2 years of age. Children born at or before 33 weeks of pregnancy scored significantly lower on thinking and motor skill tests compared to children born at full term — about 11 points lower on cognitive scores and 15 points lower on motor scores, even after accounting for many other medical and social factors.
The study also found that factors beyond prematurity contributed to worse outcomes, including lower caregiver education levels, Black race, longer hospital stays, and having a genetic diagnosis alongside heart disease. Together, these factors explained between 17% and 26% of the variation in test scores, meaning that a large portion of what drives developmental outcomes in this group is still not fully understood. Notably, the motor (movement and coordination) domain was the area where the study's model was best able to explain differences between children.
This research suggests that premature babies with congenital heart disease represent a particularly vulnerable group who may need extra monitoring and early developmental support. The findings highlight the importance of close developmental follow-up for these children and point to the need for interventions that address not only medical factors but also social and family-related influences on child development.
Katz J, Gauvreau K, Butler S, Sadhwani A, Levy P, Kaza A, et al.. (2026). Prematurity Predicts Neurodevelopmental Outcomes in Congenital Heart Disease.. Journal of the American Heart Association. https://doi.org/10.1161/JAHA.125.047668