Those diagnosed were also taking psychotropic antidepressant medication as well
. While on the antidepressants, the BDNF levels decreased for both the PNES and epileptic groups when compared to the control group. However, when all the patients in the PNES group were compared to the control group, there were no significant decreases in BDNF levels. This leads scientists to believe that there is a link between lower levels of BDNF and non-epileptic seizures.
After this initial study, scientists developed a hypothesis that stated that decreased BDNF levels may not be related to seizure episodes but rather to stress levels. Subjects showed decreased levels of BDNF when showing elevated levels of stress. Patients fearing their next seizure exhibited higher stress levels and lower BDNF levels.
Characteristics of Psychogenic Non-Epileptic Seizures (PNES)
Nearly 75 percent of these patients are women. Most individuals who experience this phenomenon are under extreme stress. Many are victims of child abuse, bullying in adulthood, adverse family dynamics or other traumatic events. Most women exhibit this behavior in their late teens to early twenties.
PNES patients often have seizures that last more than two minutes and patients may bite their tongue during seizure. Patients may also bite the inside of their mouths during the non-epileptic seizure. Their eyes are typically closed during a seizure and cannot be forced open. These symptoms or occurrences are rare in epileptic seizures.
PNES may be diagnosed through long term video EEG monitoring. Conventional EEG monitoring is not reliable in diagnosing PNES. These machines often produce false positives that can lead to misdiagnosis.