Predictors of Neurodevelopmental and Mental Health Diagnoses in Congenital Heart Disease: A Danish Population-Based Cohort Study.

Background: Over 35% of Danish children with congenital heart disease (CHD) are diagnosed with or treated for a neurodevelopmental or mental health condition. We examined child clinical, parent socioeconomic, and family health factors associated with 4 common diagnostic groups in children with CHD: developmental disorders, intellectual disability, attention-deficit/hyperactivity disorder, and anxiety and mood disorders.

Methods: This population-based cohort study identified children aged <18 years with CHD from 1996 to 2017 by linking individual-level data across Danish health and social registries, excluding children with a neurodevelopmental or mental health diagnosis, by International Classification of Diseases, Tenth Revision codes, before the index date (ie, CHD diagnosis). Using age as a time scale, we computed cumulative incidence by the age of 18 years, incidence rates, and crude and adjusted hazard ratios for each diagnostic group. Hazard ratios were adjusted for child sex and year of CHD diagnosis. In addition, cumulative days in hospital were adjusted for CHD complexity.

Results: In 16 473 children with CHD (male, 50.9%; median age at index date, 0.1 [interquartile range, 0.0-1.3] years), the cumulative incidence by the age of 18 years was 7.5% (95% CI, 7.0%-8.1%), 5.0% (95% CI, 4.6%-5.5%), 5.8% (95% CI, 5.3%-6.3%), and 10.3% (95% CI, 9.6%-11.1%) for these 4 diagnostic groups, respectively. Cumulative days in hospital within the first year after CHD diagnosis were the strongest clinical predictor of neurodevelopmental and mental health diagnoses, followed by sex, the presence of a genetic syndrome, and small for gestational age birthweight. Multiple socioeconomic metrics, including maternal or paternal age <25 years, low education (9-10 years), unemployment, and maternal marital status (eg, single or divorced), were predictors, particularly for attention-deficit/hyperactivity disorder and intellectual disability. Maternal and paternal mental health diagnoses were predictors of all 4 diagnostic groups.

Conclusions: We identified clinical, socioeconomic, and parent mental health factors associated with neurodevelopmental and mental health diagnoses in children with CHD. These data may inform early identification of these conditions and guide prevention and resource allocation.