The risk of epilepsy is higher in children with congenital heart disease (CHD) compared with the general population, even if the condition is mild and does not require surgical intervention, according to a study published in the scientific journal, Circulation.
This finding suggests that epilepsy in children with CHD may be a consequence of ‘non-surgical’ factors, such as an insufficient supply of oxygen to the brain during development and subsequent brain abnormality. However, the authors do speculate the existence of a genetic link between congenital heart disease and epilepsy.
For the study, the team, led by Dr Morten Olsen, identified children born with CHD between 1980 and 2010, using data from population-based registries covering all hospitals in Denmark. All of the children that were included in the study were diagnosed with CHD by the age of 15. For each child with CHD, the scientists identified 10 healthy children who were the same age and sex for comparison.
The results showed that there were 15,222 children born and diagnosed with CHD in Denmark during this period. A little more than half of them (51%) were male and 49% were female. Five percent of the children were diagnosed with epilepsy by the time they were 15 years of age. When only children born with CHD without extra-cardiac (outside of the heart) malformations were considered, this figure was 3%. It was more likely for children with CHD to develop epilepsy before the age of five than after the age of five.
The likelihood of developing epilepsy was not influenced by the age of the child when they had heart surgery, but it was highest among children who underwent multiple surgeries. However the risk of epilepsy was also higher than in the general population for children with mild CHD who did not undergo surgery.
Although it was previously known that neurological complications are associated with congenital heart disease, this is the first study that examined the long-term risk of epilepsy in people with congenital heart defects compared with the general population.
Previous work has identified genetic mutations that may link CHD with neurodevelopmental disabilities. According to the authors “there may be an as-yet-undiscovered genetic explanation for the heightened risk of epilepsy in the [CHD] population”.
It is important to note that the increased risk of epilepsy that was observed in this study could be linked to other factors such as the mother having epilepsy, and the foetus being exposed to antiepileptic drugs in the mother’s uterus. However in the group with CHD that was analysed, the proportion of mothers with epilepsy was very low and so it is unlikely to be the only mechanism explaining the increased risk of epilepsy.
Author: Dr Özge Özkaya