Significance of the EEG and Epileptiform Abnormalities in Antiepileptic Drug Discontinuance

Long-Term Pharmacological and Psychosocial Outcomes of Adolescent-Onset Epilepsy: A Single-Center Experience

Purpose: Despite the high incidence of epilepsy during adolescence, little attention has been paid to the outcomes and prognosis of adolescent-onset epilepsy. The aim of this study was to investigate the long-term pharmacological and psychosocial outcomes of adolescent-onset epilepsy.Methods: From 1993 to 2019, the electronic medical records of adolescent-onset epilepsy patients were retrieved from Asan Medical Center Children’s Hospital. Seizure outcomes were evaluated based on the seizure-free period at last contact. Possible predictors of remission, relapse, and intractability were investigated. Neuropsychiatric comorbidities, socioeconomic status, and transition outcomes were also assessed. Results: In total, 137 patients were enrolled in this study. The median age at diagnosis of epilepsy was 14 years and the mean duration of therapy was 13.0 years. During follow-up, 93 patients (67.9%) achieved terminal remission, of which 27 cases (19.7%) resolved. Relapse after withdrawal of medication occurred in 74 patients (54.0%), and the presence of electroencephalographic abnormalities (odds ratio [OR], 8.23; 95% confidence interval [CI], 1.39 to 48.87; P=0.020), poor adherence (OR, 4.84; 95% CI, 2.13 to 11.02; P=0.000), and history of febrile seizures (OR, 4.10; 95% CI, 1.21 to 13.93; P=0.024) were risk factors for relapse. Neurodevelopmental and psychological comorbidities were documented in 17 (12.4%) and 12 (8.8%) patients, respectively. Thirty-six (26.3%) patients transferred to adult clinics, at a mean age of 21.9 years. Conclusion: This study showed overall favorable seizure outcomes with a high rate of remission, but with frequent relapse after withdrawal.

Risk factors of recurrence after drug withdrawal in children with epilepsy

This study aimed to evaluate the risk factors for recurrence in pediatric patients with epilepsy following normal antiseizure medication (ASM) treatment and drug withdrawal. We retrospectively analyzed 80 pediatric patients who received treatment at the Qilu Hospital of Shandong University between January 2009 and December 2019 after at least 2 years of seizure-free and normal electroencephalography (EEG) before the regular drug reduction. Patients were followed-up for at least 2 years and divided into the recurrence and nonrecurrence groups based on whether relapse occurred. Clinical information was gathered, and the risk variables for recurrence were statistically analyzed. Post 2 years of drug withdrawal, 19 patients showed relapses. The recurrence rate was 23.75%, and the mean time of recurrence was 11.09 ± 7.57 months, where 7 (36.8%) were women and 12 (63.2%) were men. In all, 41 pediatric patients were followed-up until the 3rd year, of which 2 (4.9%) patients experienced a relapse. Among the remaining 39 patients without relapse, 24 were followed-up until the 4th year, and no recurrence occurred. After being monitored for >4 years, 13 patients experienced no recurrence. The differences in the history of febrile seizures, combined use of ≥2 ASMs, and EEG abnormalities after drug withdrawal between the two groups were statistically significant (p < 0.05). Multivariate binary logistic regression analysis revealed that these factors are independent risk factors for recurrence after drug withdrawal in children with epilepsy: history of febrile seizures (OR = 4.322, 95% CI: 1.262-14.804), combined ASM use (OR = 4.783, 95% CI: 1.409-16.238), and EEG abnormalities after drug withdrawal (OR = 4.688, 95% CI: 1.154-19.050). In summary, our results suggest that the probability of seizure recurrence following drug cessation may be greatly increased by a history of febrile seizures, concomitant use of ≥2 ASMs, and EEG abnormalities after drug cessation. The majority of recurrences occurred in the first 2 years following drug discontinuation, whereas the rate of recurrence was minimal thereafter.

Prediction of the recurrence risk in patients with epilepsy after the withdrawal of antiepileptic drugs

Many seizure-free patients who consider withdrawing from antiepileptic drugs (AEDs) hope to discontinue treatment to avoid adverse effects. However, withdrawal has certain risks that are difficult to predict. In this study, we performed a literature review, summarized the causes of significant variability in the risk of postwithdrawal recurrent seizures, and reviewed study data on the age at onset, cause, types of seizures, epilepsy syndrome, magnetic resonance imaging (MRI) abnormalities, epilepsy surgery, and withdrawal outcomes of patients with epilepsy. Many factors are associated with recurrent seizures after AED withdrawal. For patients who are seizure-free after treatment, the role of an electroencephalogram (EEG) alone in ensuring safe withdrawal is limited. A series of prediction models for the postwithdrawal recurrence risk have incorporated various potentially important factors in a comprehensive analysis. We focused on the populations of studies investigating five risk prediction models and analyzed the predictive variables and recommended applications of each model, aiming to provide a reference for personalized withdrawal for patients with epilepsy in clinical practice.

The clinical value of long - term electroencephalogram (EEG) in seizure - free populations: implications from a cross-sectional study

Backgroud

This study aimed to explore the clinical value of long - term electroencephalogram (LTM EEG) in seizure-free individuals taking antiepileptic drugs (AEDs) for more than 2 years. We try to look for clinical factors associated with epileptiform activity on LTM EEG in seizure free patients. We hope that the detection of epileptiform activity by the LTM EEG recording can develop the better treatment strategy.

Methods

The LTM EEG recordings of 770 individuals with a definite diagnosis of epilepsy were assessed. Two hundred sixty-two individuals accorded with the inclusion criteria and exclusion criteria. We collect the demographic and clinical information and LTM EEG data of these 262 individuals. We analysed the data by one-way analysis of variance and Cox proportional hazards models.

Results

We found that more epileptiform activity were found with LTM EEG recording than regular EEG recording in seizure-free individuals. We found several clinical factors could be associated with epileptiform activity on LTM EEG in seizure free patients by a one-way analysis: symptomatic or cryptogenic epilepsy [hazard ratio (HR) = 2.6], history of cerebral trauma (HR = 7.5), and abnormal imaging findings (HR = 3.1). The following factors suggested a correlation between history of cerebral trauma (HR = 2.4) and history of cerebral surgery (HR = 3.4) with epileptiform activity on LTM EEG presentation by multivariate logistic regression analysis.

Conclusions

The study indicated a correlation of a number of factors with abnormal LTM EEG presentation: symptomatic or cryptogenic epilepsy, history of cerebral trauma, history of cerebral surgery, and abnormal imaging findings. The LTM EEG recording may help find epileptiform activity in high risk seizure-free individuals. The individuals need be reevaluated the therapeutic strateagies, and increase the hope to reach real seizure-free.

Risk factors for seizure reoccurrence after withdrawal from antiepileptic drugs in individuals who have been seizure-free for over 2 years

Purpose

To observe risk factors for recurrence after withdrawal from antiepileptic drugs.

Methods

We assessed 1282 patients with a definite diagnosis of epilepsy.

Results

In total, 292 patients between 14 and 80 years of age were grouped according to risk factors for recurrence. Of these individuals, 119 discontinued AED(s) and relapsed. The relapse rate was 34.4 per 100 person-years. We used a Cox regression for multivariate analysis to investigate the influence of the following on seizure recurrence: receiving more than one type of AED (HR = 2.53, 95% CI 1.24–5.16) and more than 6 months prior to initiation of AED treatment (HR 1.47, 95% CI = 1.004–2.15).

Conclusions

Although the decision to discontinue AED treatment necessitates an individual evaluation of each patient, our study suggests that there may be a high risk of recurrence in individuals who: were receiving more than one AEDs and had initiated their AED treatment more than 6 months after the initial appearance of epilepsy symptoms.

[Paraclinical explorations in epilepsies]

Paraclinical explorations in epilepsy depend on the clinical situation of the occurrence of seizure. Epileptic seizure is first a possible symptom of a progressive cerebral disease or a systemic origin (toxic, metabolic, iatrogenic). In this situation, the aim of urgent explorations is to find the etiology of the seizure. If epileptic seizure is related to an epilepsy onset, paraclinical explorations are aimed to characterize an epileptic syndrome (idiopathic or symptomatic). Then EEG and cerebral imaging are imperative, eventually completed by specialized investigations (genetics, metabolic, functional imaging).