The annual suicide mortality rate among people with epilepsy is 22 percent higher than in the general population, according to a new study by researchers at Columbia University’s Mailman School of Public Health and the Centers for Disease Control (CDC).
The research, which is the first to measure suicide rates among people with epilepsy in a large U.S. general population, also investigated suicide risk factors specific to the disease. The findings are published online in the journal Epilepsy and Behavior.
The study was based on data from the U.S. National Violent Death Reporting System, a multiple-state, population-based, surveillance system that collects information on violent deaths, including suicide.
The researchers identified 972 suicide cases with epilepsy and 81,529 suicide cases without epilepsy in 17 states among people 10 years old and older between the years 2003 and 2011. By comparing the number of cases between those with epilepsy and those without epilepsy, the researchers were able to estimate suicide rates, evaluate suicide risk, and investigate suicide risk factors specific to epilepsy.
In 16 of the 17 states providing continual data from 2005 through 2011, they also compared suicide trends in people with epilepsy and without epilepsy.
The researchers found that, compared with the non-epilepsy population, those with epilepsy were more likely to have died from suicide in houses, apartments, or residential institutions — 81 percent versus 76 percent, respectively — and were twice as likely to poison themselves (38 percent versus 17 percent).
Furthermore, more people with epilepsy aged 40-49 died from suicide than comparably aged persons without epilepsy (29 percent vs. 22 percent). The proportion of suicides among those with epilepsy increased steadily from 2005 through 2010, peaking significantly in 2010 before falling.
“Of particular significance is what we learned about those 40 to 49 years old,” said co-author Dale Hesdorffer, Ph.D., professor of Epidemiology at the Mailman School of Public Health. “Efforts for suicide prevention should target people with epilepsy in this age category specifically.”
“Additional preventive efforts should include reducing the availability or exposure to poisons, especially at home, and supporting other evidence-based programs to reduce mental illness comorbidity associated with suicide.”
Epilepsy is a chronic disorder of the brain that causes recurrent, unprovoked seizures. Some causes of epilepsy include stroke, brain tumor, traumatic brain injury, or central nervous system infection; in many cases, however, the cause is unknown. Based on the latest estimates, about 1.8 percent of adults aged 18 years or older have had a diagnosis of epilepsy or seizure disorder, according to the CDC.