Abstracts

Rationale: Most patients with idiopathic generalized epilepsy have good prognosis and will outgrow seizures. These patients are typically weaned off of daily anti-seizure medications (ASM) after 2 years of seizure freedom. But it is unclear whether these patients require regular follow up to see if seizure recurrence has occurred. There are no clear guidelines if electroencephalogram (EEG) is needed in these patients after successfully withdrawal of ASM following seizure freedom. It is also unclear if they require restart of ASM if the EEG shows abnormal findings but without any clinical seizure relapse.  There has been very limited study to this date discussing risk factors for seizure recurrence in patients with idiopathic generalized epilepsy. Moreover, it is unknown if abnormal EEG always means seizure recurrence especially in patients with idiopathic generalized epilepsy. The aim of this study is to evaluate how often patients with Idiopathic generalized epilepsy get EEG after seizure medications withdrawal following seizure freedom and get restarted on ASM based on EEG abnormality without any clinical seizure relapse.

Methods: This was a retrospective chart review study. Data was collected using electronic medical records in pediatric patient (< 18 yr) with history of idiopathic generalized epilepsy who have been successfully weaned off of anti-seizure medications at Penn State Children’s Hospital. Data were collected looking into whether or not these patients had EEG afterwards, reasons for EEG obtained and if they were restarted on ASM based on abnormal EEG findings. Patient who had EEG due to reasonable cause such as seizure recurrence were excluded from the study.

Results: We found 40 patients who met our inclusion criteria. Eleven out of 40 patients (27.5%) had repeat EEG obtained within 6 months after seizure medications were stopped following seizure freedom. Of those, 3/11 (27%) had abnormal (generalized epileptiform discharges) EEG findings. Of these, although 2/3 (66%) were restarted on anti-seizure medications based on abnormal EEG findings, none had clinical seizure relapse.

Conclusions: Obtaining repeat EEG in these patient populations after seizure medications withdrawal following seizure freedom is not rare. Also, it is not rare to identify abnormal findings if EEG is obtained in these patients. Patients also tend to get restarted on ASM if EEG shows any abnormal findings even without any clinical seizure relapse. However, unnecessary EEG can be associated with high healthcare cost and Seizure medications have side effects and can potentially cause poor long-term neurodevelopmental outcome. So, we hypothesize that if patients with Idiopathic generalized epilepsy are doing well clinically following seizure medication withdrawal, EEG may not be helpful or require, however our study is limited due to small sample size, and single center study. So further larger study with randomized controlled trials would be necessary to further evaluate the utility of EEG in these patient populations.

Funding: None