Value Of Long Term Video Electroencephalography To Instruct Discontinuation Of Anti-epileptic Drugs In Patients With Epilepsy

Objective To explore the prognostic value of normal 24 hour video-electroencephalography(24h VEEG) with different frequency before anti-epileptic drugs withdrawal and value of changed 24 h VEEG during and after anti-epileptic drugs withdrawal in cryptogenic epilepsy among seizure free more than 3 years. Methods A retrospective study was conducted in the Neurology outpatient and the Center of Epilepsy Department of Xi Jing hospital.The subject who had been seizure free more than 3 years were divided into continual 2 normal group and 1 normal group according to the nomal frequence of 24 h VEEG(every year) before discontinuation from January 2013 to December 2014,and then followed up to replase or to May 2016.The recurrence and cumulative recurrence rate of the two group after withdrawal AEDs were compared with chi-square or Fisher’s exact test and Kaplan-Meier survival curve.A Cox proportional hazard model was used for multivariate analysis to identify the risk factors as significantly correlated with seizure recurrence after using the method of univariate analysis. P value of < 0.05 was considered significant, and all P-values were two-tailed. Results 95 unknown cause epilepsy patients between 9 to 45 years old were recruited and followed up more than 1year,63 in continual 2 normal normal 24 h VEEG group(33 males, 30 femals)and the rate of replase was9.5%(6/63).32 in 1 normal 24 h VEEG group(19 males, 13 femals) and replase rate was 25%(8/32). The cumulated recurrence rates in continual 2 normal 24 h VEEG group vs 1 normal 24 h VEEG group were 1.6% vs 3.1%、3.2% vs 12.5%、4.9% vs 25%、5.5% vs 29.6%、10.9% vs 26.9% at 6、12、18 、24 months and end point following AEDs withdrawal and there was statistically difference between the 2 groups.Factors associated with increased risk were adolescent onset epilepsy(HR 2.404)、history of withdrawal recurrence(HR 7.186)and abnormal 24 h VEEG( epileptic-form discharge)(HR 8.222)during or after withdrawal AEDs. The recurrence rate of each group in which abnormal 24 h VEEG vs unchanged 24 h VEEG during or after withdrawal AEDs was respectively 100% vs 5.0%(p=0.001)、80% vs15.38%(p=0.009). Conclusions Continual 2 normal 24 h VEEG before withdrawal AEDs had a significantly lower recurrence rate than the reported overall rates and it could be considered as an evidence to guide physicians and eligible candidates who had been seizure free more than 3 years to make the withdrawal decision. Epileptic patients with adolescent onset epilepsy,a positive past history of seizure recurrence and abnormal 24 h VEEG( epileptic-form discharge) during or after withdrawal AED had a high risk of replase,especially patients with the presence of 24 h VEEG abnormalities is associated with a high probability of seizures occurring. Stopping AED should be proceeded with caution...