Population-based study of cognitive outcomes in congenital heart defects

Objective To characterise and compare cognitive outcomes in children with operated (open-heart surgery) and non-operated (catheter-based interventions only or no intervention) congenital heart defects (CHD) and to determine associated risk factors. Design This prospective population-based study reports outcomes of 3-year-old children with CHD with or without open-heart surgery. Main outcome measures Standardised cognitive scores (mean scores and proportions below normative values) were assessed with the Kaufman Assessment Battery for Children II. We analysed demographic, perinatal and operative variables as predictors of cognitive outcomes. Results 419 children participated (154 with open-heart surgery; 265 without surgery). Global cognitive scores did not differ between the groups. Compared with the non-operated group, children who underwent surgery obtained lower scores in expressive language (p=0.03) and logical reasoning (p=0.05). When compared with test norms, the frequency of global cognitive scores >1 SDs below the expected mean was higher in the surgical group (25% vs 16% in the general population) (p=0.03). A higher-than-expected proportion of children in the non-operated group scored >2 SDs below the expected mean (7% vs 2%) (p=0.05). Being small for gestational age (SGA) significantly increased the risk of cognitive impairment in the surgical group, after adjustments for multiple covariates including maternal education, complexity of the CHD and operative-related variables (adjusted OR=5.9; 95% CI (1.7 to 20.1)). Conclusions Despite mean scores within the normative range, a high proportion of preschool children with CHD with or without surgery are at early cognitive risk. SGA is a strong predictor of the neurodevelopmental prognosis in CHD.