Major structural congenital anomalies and causal pathways in people with cerebral palsy.

Aim: To determine the proportion of persons with cerebral palsy (CP) with major congenital anomalies, factors associated with the presence of anomalies, body systems involved, potential contribution to CP aetiology, and causal pathway subgroups implicated.

Method: This population-based, observational study involved a cohort of 2238 persons born in one Australian state between 1999 and 2017. Major congenital anomalies were classified as affecting cerebral, cardiac, or other body systems, with further categorization as single or multisystem. We determined the potential for anomalies to contribute to the development of CP across causal pathway subgroups that were broadly categorized as developmental or involving destructive brain insults.

Results: Of persons with CP, 23% had major congenital anomalies and 17% of the cohort had anomalies that potentially contributed to the development of CP. Consistent with higher odds of parental consanguinity, maternal grand multiparity, and dysmorphic features in the group with anomalies, 82% of pathogenic anomalies, present in 14% of the cohort, were cerebral and involved developmental causal pathways. Only 3% (predominantly severe cardiac anomalies) were related to destructive brain insults.

Interpretation: The study provides context for the impact on rates of CP of preventive measures or other changes in incidence or management of congenital anomalies.