“Seizures while driving pose substantial risks for those experiencing them and for others on the road,” said study author Dr. Jacob Pellinen, of the University of Colorado in Aurora and a member of the American Academy of Neurology.
“While medication may make it possible for some people with epilepsy to safely drive, they must first be diagnosed. Our study sought to define how often seizures happen while driving before a diagnosis and then how long it takes before a person is diagnosed. Our results can then help inform how to diagnose people sooner, with a goal of lowering the number of pre-diagnosis seizures on the road,” Pellinen said in an academy news release.
More than half of all people with epilepsy have focal epilepsy, which involves recurring seizures that affect one half of the brain.
Researchers focused on 447 people with focal epilepsy. These patients were age 29, on average, when they experienced their first seizure.
Looking at medical records from before the epilepsy diagnoses, investigators found that 23 participants had one or more seizures while driving, for a total of 32 seizures.
Among them, seven, or 30%, had more than one seizure while driving prior to diagnosis. For six people, about 26% of the group, it was their first seizure.
These seizures while driving resulted in 19 motor vehicle accidents and 11 hospitalizations for injuries ranging from a tongue bite and a dislocated thumb to a near drowning.
In the United States, there are over 126,000 driving-age people in the country diagnosed with epilepsy each year, Pellinen said.
“From our study, we estimate nearly 6,500 people per year may experience pre-diagnosis seizures while driving in the United States alone, leading to nearly 4,000 possible motor vehicle accidents and over 2,200 hospitalizations," Pellinen said. "Much of this may be preventable by earlier diagnosis.”
The average time from experiencing a first seizure to experiencing a seizure while driving was 304 days, the authors found. The average time between a person’s first seizure while driving to being diagnosed with epilepsy was 64 days.
People with what are called non-motor seizures, where movement stops and a person may simply stare, had a nearly five times greater risk of experiencing a seizure while driving prior to diagnosis than those who had a motor seizure. The latter can include sustained jerking movements or muscles becoming weak or rigid.
Having a job made a difference in the findings, too. People who were employed were four times more likely to experience a seizure while driving prior to diagnosis than those not working.
Some of the seizure history was self-reported, which is considered a study limitation. It was also a small study and examined only one type of epilepsy. Future studies are needed in larger groups of people.
The findings were published June 7 online in Neurology.
The U.S. Centers for Disease Control and Prevention has more on epilepsy.
SOURCE: American Academy of Neurology, news release, June 7, 2023