Congenital Heart Defects and Indices of Fetal Cerebral Growth in a Nationwide Cohort of 924,422 Liveborn Infants
Background—Neurodevelopmental disorders are the most common and distressful comorbidities associated with congenital heart defects (CHD). Head circumference at birth (HC), a proxy for prenatal cerebral growth, is an established risk factor for neurodevelopmental disorders.
Methods and Results—In a nationwide cohort, we included all 924,422 liveborn Danish singletons, 1997-2011. CHD was present in 5,519. The association between CHD and growth indices was analyzed by multivariable linear regression, adjusted for potential confounders. We report mean differences in gestational age specific z-scores compared to the general population. CHD was associated with lower HC z-scores, -0.10 (95%CI -0.13,-0.08). Several CHD subtypes were associated with smaller HC, e.g. hypoplastic left heart syndrome -0.39 (95%CI -0.58,-0.21), common arterial trunk -0.41 (95%CI -0.74,-0.09), major ventricular septal defects -0.25 (95%CI -0.35,-0.15). Other single ventricle defects, transposition of the great arteries, tetralogy of Fallot, and anomalous pulmonary venous return were also associated with smaller HC. Transposition of the great arteries was associated with smaller HC relative to birth weight -0.26 (95%CI -0.39,-0.13). Major ventricular septal defects were associated with larger HC relative to birth weight. The results were consistent under various conditions, e.g. when siblings of infants with CHD (n=5,311) or infants with other major malformations (n=24,974) were used as the reference.
Conclusions—Several subtypes of CHD were associated with smaller HC. The associations with major ventricular septal defects, common arterial trunk, and anomalous pulmonary venous return have not previously been described. Only infants with transposition of the great arteries had smaller HC relative to birth weight.
- Received August 18, 2015.
- Revision received December 16, 2015.
- Accepted December 29, 2015.