Having a close relative with epilepsy may increase a person's risk of developing autism, a new study suggests.
"Other studies have linked the two conditions, however, our study looks specifically at the brothers and sisters and sons and daughters of people with epilepsy to determine a possible autism risk in these relatives," said Helene E K Sundelin from University Hospital in Sweden.
For the study, researchers looked at a data registry and identified 85,201 people with epilepsy, as well as all of their siblings (80,511 people) and offsprings (98,534 people).
Each person with epilepsy was compared with five people without epilepsy of similar age, sex and from the same county during the same period.
The siblings and offspring of those with epilepsy were also compared with siblings and offspring of people without epilepsy. Siblings and offspring who had epilepsy were excluded from the research.
During the average six-year follow-up period of the study, 1,381 of participants with epilepsy and 700 of the people without epilepsy were diagnosed with autism, researchers said.
People with epilepsy were therefore at increased risk of being diagnosed with autism (1.6 per cent compared to 0.2 per cent), with the highest risk seen in those diagnosed with epilepsy in childhood (5.2 per cent), they said.
The study found a 63 per cent increased risk of developing autism for siblings and offspring even when the person with epilepsy was excluded, researchers said.
Offspring of mothers had a 91 per cent increased risk and offspring of fathers had a 38 per cent increased risk, they said.
The findings were published in the journal Neurology.
