A longitudinal study of epilepsy and other central nervous system diseases in individuals with and without a history of infantile autism

Objective: To compare the prevalence and types of epilepsy and other central nervous system (CNS) diseases in a clinical sample of 118 individuals diagnosed as children with infantile autism (IA) with 336 matched controls from the general population. Methods: All participants were screened through the nationwide Danish National Hospital Register (DNHR). The average observation time was 30.3 years (range 27–30 years), and mean age at follow-up was 42.7 years (range 27–57 years). Results: Of the 118 individuals with IA, 29 (24.6%) were registered with at least one epilepsy diagnosis against 5 (1.5%) in the comparison group (p < 0.0001; OR = 21.6; 95% CI 8.1–57.3). Other CNS diseases occurred with low frequency in both groups and only cerebral palsy, unspecified (p = 0.02) was significantly more frequent among participants with a history of IA. Conclusions: Our study lends further support to the notion that epilepsy, but not other CNS diseases, is a common comorbid condition in IA. Low intelligence, but not gender, was a risk factor for epilepsy in IA.