Predictive Value of Isolated Epileptiform Discharges for a Favorable Therapeutic Response to Antiepileptic Drugs in Nonepileptic Psychiatric Patients

Abstract

The efficacy of antiepileptic drugs (AEDs) in treating behavioral symptoms in nonepileptic psychiatric patients with abnormal EEGs is currently unknown. Although isolated epileptiform discharges have been reported in many psychiatric conditions, they are most commonly observed in patients with aggression, panic, or autistic spectrum disorders. The literature search was guided by 3 criteria: (1) studies had patients who did not experience seizures, (2) patients had EEGs, and (3) an AED was administered. Most important finding is that the number of "controlled" studies was extremely small. Overall, most reports suggest that the use of an AED can be associated with clinical and, at times, improved EEG abnormalities. Additionally, six controlled studies were found for other psychiatric disorders, such as learning disabilities with similar results. Overall, the use of anticonvulsants to treat nonepileptic psychiatric patients needs further controlled studies to better define indications, adequate EEG work-up, best AED to be used, and optimal durations of treatment attempts.

EEG changes associated with autistic spectrum disorders

“…Finally, it is not known whether currently available seizure medications are effective in normalizing hyperexcitable brain tissue that has not yet become capable of inducing seizures. Scattered reports suggest that a few of these medications may have some efficacy in this regards but further research is needed to examine these efficacies, particularly in newly diagnosed ASD patients (Boutros et al 2014).…”

“…While there were no clear correlation between the discharges and particular aberrant behaviors, epileptic discharges were significantly more frequent during periods when the child was left alone and decreased when the child interacted with others. We have recently proposed that IEDs may be reflective of some degree of cortical hyperexcitability (Boutros et al 2014); however, a strong link between IEDs in the absence of seizures and behavioral symptoms remains far from being well established (So 2010).…”

“…It may be necessary for this line of investigation to follow a proscribed and systematic progression of EEG findings to eventually lead to clinical usefulness (Arfken et al 2009;. It is presumed that a robust biological finding can be identified by various independent groups and its ability to differentiate a particular target patient population from either non-patients or other patients with disorders commonly appearing on the same differential diagnostic list (Boutros et al, 2014). Hence, the purpose of the current review is to highlight any findings that seem to have some level of consistency (Webb et al 2013) and any possible links to abnormalities reported using standard EEG methodology.…”

Personalized Medicine: Review and Perspectives of Promising Baseline EEG Biomarkers in Major Depressive Disorder and Attention Deficit Hyperactivity Disorder

“…Furthermore, there is some evidence that antidepressant treatment augmentation with anti-epileptic drugs is effective in treatment resistant MDD [60,61], although data about the association of response and epileptiform discharges are lacking. As a further example, previous studies have demonstrated an association between paroxysmal EEG activity and panic attacks [for a review, see [62], [63]]. Patients with panic disorder and epileptiform EEG patterns have been found to clinically respond to anticonvulsants [64], thus suggesting that there could be a subgroup of psychiatric patients in whom paroxysmal/epileptiform EEG activity could be associated with their psychiatric complaints and for whom anticonvulsant treatment could be a choice for augmentation of treatment or as stand-alone treatment.…”

The forsaking of the clinical EEG by psychiatry: how justified?

“…The most important unanswered question remains the value of detecting IED activity in a nonepileptic psychiatric patient in predicting favorable responses to anticonvulsant treatment. 2 Slowing of the EEG is also seriously underinvestigated in psychiatric patients. The extent of medical follow-up of abnormal screening EEGs secured from psychiatric patients, particularly those reporting slow-wave abnormalities as a single finding, varies widely.…”