People who have suffered from serious depression or who have attempted suicide could be at increased risk of developing epilepsy. That’s according to a team of American and Icelandic researchers who said more work was needed to explain the link, which they speculated could be related to levels of the neurotransmitters noradrenalin and serotonin.
Dale Hesdorffer (Columbia University) and colleagues recruited 324 Icelandic adult and child participants (median age 34 years) who had recently suffered two or more seizures that weren’t caused by fever, head trauma or central nervous system infection, thus pointing to a diagnosis of epilepsy. Six hundred and forty-seven age-matched control participants who lacked a history of epilepsy were selected using the Icelandic population registry. All the adult participants were interviewed over the phone to determine whether they had ever suffered from major depression or had attempted suicide. For both groups, only depression or suicide attempts that occurred prior to when the seizure patients had suffered their seizures were counted. The same information was obtained for the child participants by interviewing their parents.
Child and adult participants who had recently experienced unexplained seizures were 1.7 times more likely to have previously suffered from major depression than the control participants (i.e. 12 per cent of the seizure group vs. 7.4 per cent of the control group). And they were 5.1 times more likely to have attempted suicide in the past (i.e. 6.5 per cent of the seizure group vs. 1.4 per cent of the control group). Previous attempted suicide remained significantly more prevalent among the participants who’d recently suffered seizures, even after taking into account rates of prior depression and alcohol consumption.
“Clearly, patients presenting with a new onset unprovoked seizure should be evaluated for a history of suicide attempt and major depression”, the researchers advised.
Hesdorffer, D.C., Hauser, W.A., Olafsson, E., Ludvigsson, P. & Kjartansson, O. (2005). Depression and suicide attempt as risk factors for incident unprovoked seizures. In Press, Annals of Neurology. DOI: 10.1002/ana.20685.