Epilepsy in patients with congenital heart disease: A nationwide cohort study

Background Congenital heart disease (CHD) is the most common congenital defect, and reports suggest an increased risk of subsequent epilepsy. We used Swedish comprehensive population-based registers to investigate the risk of epilepsy in patients with CHD compared to matched controls and identify underlying factors of epilepsy. Methods All patients with CHD born between 1970 and 2017 and 10 age- and sex-matched controls were included. Epilepsy was ascertained by International Statistical Classification of Diseases and Related Health Problems codes, and the cumulative hazard of epilepsy was described using Cox regression. Results The study cohort consisted of 71,941 patients with CHD and 714,462 matched controls. The cumulative incidence of epilepsy in the study period was 3% in patients with CHD and 0.9% in controls. The risk of epilepsy was 3.6 times higher (95%, confidence interval: 3.4-3.8) in patients with CHD than in controls. Among patients with CHD, several brain comorbidities, including intellectual disability and stroke, as well as having undergone more than two cardiac interventions were significantly associated with epilepsy in a multivariable model. Conclusions In this nationwide, register-based cohort study, we found an almost fourfold increased risk of epilepsy in patients with CHD compared to controls; however, the absolute risk was low. Among the identified risk factors, stroke may be potentially preventable.