Risk factors for recurrence after drug withdrawal in childhood epilepsy

A meta-analysis of the relationship between abnormal pretreatment EEG and epilepsy recurrence

BACKGROUND

Researchers have studied the risk factors for epilepsy recurrence among patients who withdraw from antiseizure medication (ASM). These studies aimed to determine the optimal time for ASM withdrawal. EEG findings are one of the risk factors that has been studied. However, it remains unclear whether abnormal pretreatment EEG findings are a risk factor for recurrence after ASM withdrawal. We performed this meta-analysis to clarify this issue.

METHODS

We retrieved literature from the PubMed and Embase databases, and used the NewcastleOttawa Scale to evaluate the methodological quality of the included studies. RevMan 5.3 software was used to analyse the data.

RESULTS

In total,710 articles were retrieved from the databases. Ultimately, after screening, 11 articles involving 1686 patients with epilepsy were included. Compared with that for a normal EEG, the odds ratio (OR) for an abnormal EEG was 1.10 (P=0.50), with an I2 value of 32% (P=0.15). Subgroup analysis revealed that the children-to-adolescents subgroup had an OR of 1.21 (P=0.27), and the children-to-adults subgroup had an OR of 0.64 (P=0.14) for an abnormal EEG. A separate subgroup analysis revealed that the focal epilepsy subgroup had an OR of 1.30 (P=0.37), and the generalized epilepsy and focal epilepsy subgroup had an OR of 1.07 (P=0.67) for an abnormal EEG.

CONCLUSIONS

The risk of epilepsy recurrence is not related to pretreatment EEG findings, regardless of age or epilepsy classification. The associations of pre- and posttreatment EEG alterations with epilepsy recurrence are controversial. Due to the limitations of our article, further research is needed.

Withdrawal of antiseizure medications - for whom, when, and how?

INTRODUCTION

Epilepsy is a chronic disorder of the brain characterized by an enduring predisposition to generate epileptic seizures. Most patients can achieve complete seizure control (seizure freedom) with antiseizure medications (ASMs). In some of them, the withdrawal of ASMs can be considered. Guidance is required to identify patients in whom drug discontinuation can be safely attempted and to inform when and how ASM withdrawal can be done.

AREAS COVERED

In this perspective, the authors discuss the evidence on ASM withdrawal in epilepsy patients who are seizure-free and provide some suggestions on how to do it effectively in clinical practice, minimizing the risk of seizure recurrence.

EXPERT OPINION

The decision of discontinuing ASMs in epilepsy patients should rely on an accurate estimate of seizure recurrence risk. Whenever possible, such a risk should be assessed on an individual basis. The decision should also consider the psychosocial and personal consequences of seizure relapse. No robust evidence is available on the safest tapering regimen.

Relapse After Drug Withdrawal in Patients with Epilepsy After Two Years of Seizure-Free: A Cohort Study

BACKGROUND AND STUDY AIMS

Antiepileptic drugs are the first choice of treatment for patients with epilepsy. However, the withdrawal of antiepileptic drugs after seizure-free remains a significant focus for the majority of patients with epilepsy and their families. In this study, we evaluated the risk factors associated with relapse after drug withdrawal in patients with seizure free for 2 years. We aimed to guide patients in seizure-free to assess the risk of drug withdrawal.

PATIENTS AND METHODS

Through screening, 452 patients with epilepsy were included in the study.Patients were followed up for at least 2 years or more. Analyzed their clinical data by applying the χ2-test, Kaplan-Meier survival analysis and multivariate Cox regression analysis.

RESULTS

423 patients completed follow-up, of which 304 cases recurred (71.9%).Related recurrence factors include age of onset, type of seizure, number of AEDs, seizure-free time before withdrawal, and electroencephalogram (EEG) results before drug withdrawal (P<0.05). The results of correlation analysis showed that age of onset, seizure frequency, seizure type, number of AEDs, the period from AEDs treatment to a seizure-free status, EEG results before drug withdrawal, and pre-medication course, were all significantly related to the recurrence of seizures after drug reduction and withdrawal (P<0.05). We identified a range of independent risk factors, including onset age, seizure frequency, Multiple AEDs and the period from AEDs treatment to a seizure-free status.

CONCLUSION

The overall recurrence rate of epilepsy in our patient cohort was high, and the peak recurrence period was within one-year of drug withdrawal. Patients with partial seizures, a short seizure-free time before withdrawal, severe EEG abnormalities before drug reduction, and a long course of the disease, are prone to relapse. Patients with an older age at onset and a high frequency of attack, those taking multi-drug combination therapy, and those that take a long time to gain control, should be managed carefully to AEDs 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.

Risk of seizure relapse and long-term outcomes after discontinuation of antiseizure medication in children with epilepsy

OBJECTIVES

The aims of this study were to evaluate the demographic and clinical characteristics of children with epilepsy who discontinued their antiseizure medication (ASM), to determine potential predictors of seizure relapse, to calculate the rate of seizure relapse, and to detect long-term seizure outcomes.

METHODS

A total of 269 seizure-free children with epilepsy who were decided to discontinue their ASM and were followed up for at least 18 months after ASM withdrawal were retrospectively evaluated.

RESULTS

The enrolled children had been followed up for a median of 46 months (range 18-126 months; IQR: 29-61) after ASM withdrawal and 90 (33.5%) of their seizures relapsed. The median time to seizure relapse was 8 months (range 0.23-117 months; IQR: 2-25). Seizure relapse occurred in 16.7% of the 90 children at 1 month, 45.6% at 6 months, 62.2% at 1 year, 74.4% at 2 years, and 94.4% at 5 years. Univariate logistic regression analyses revealed six predictors significantly related to relapse: age at first seizure, age at diagnosis of epilepsy, intellectual disability, EEG findings after ASM withdrawal, ASM tapering time, and number of seizures on ASM. In multivariate logistic regression analyses, age at first seizure, intellectual disability, and ASM tapering time were not significantly associated anymore. The other three remained independently predictive. Pharmacological control of seizures with monotherapy was restored in 93.3% of the children with seizure relapse.

CONCLUSION

This study evaluated potential predictors of seizure relapse, some of which have rarely been evaluated in previous studies. Adolescent age at diagnosis, abnormal EEG findings after ASM withdrawal, and high number of seizures on ASM were associated with a higher risk of seizure relapse. Abnormal MRI findings such as malformations of cortical development and hydrocephalus may be potential biomarkers for the risk of seizure relapse.

Abnormal electroencephalogram (EEG) after drug withdrawal is a risk factor for epilepsy recurrence in children: a systematic review and meta-analysis

BACKGROUND

The relationship between abnormal electroencephalogram (EEG) and epilepsy recurrence after antiepileptic drug (AED) withdrawal has been controversial. We aimed to explore the relationship between abnormal EEG after AED withdrawal and the risk of epilepsy recurrence in children.

METHODS

Literature retrieval was performed using the PubMed, EMBASE, Medline, CENTRAL, and China National Knowledge Infrastructure (CNKI) databases. Included literatures were subjects of pediatric epilepsy patients who discontinued medication. The recurrence rate of epilepsy in patients with normal and abnormal EEG after AED withdrawal was observed. The Newcastle-Ottawa scale (NOS) was used to evaluate the quality of literatures. The Chi-square test was used to test heterogeneity. If heterogeneity between the articles existed, a random-effects model was used; otherwise, fixed-effects models were used. Subgroup analysis was used to explore the causes of heterogeneity. The odds ratio (OR) and 95% confidence interval (CI) were calculated using the Mantel-Haenszel statistical method. OR was not adjusted for other factors.

RESULTS

A total of 843 articles were retrieved. Nine studies were included, with a total of 1,663 patients, including 1,299 patients with normal EEG and 364 patients with abnormal EEG. Compared with the normal EEG patients, the OR of recurrence rate after AEDs withdrawal was 3.02 (P=0.0003), with heterogeneity (P<0.0001). The funnel plot indicated that there was no publication bias among the studies. The not partial seizure group analysis showed OR =1.70 (P=0.003) and no heterogeneity (P=0.70) in patients with abnormal EEG compared to those with normal EEG. In the partial seizures subgroup, the OR of the recurrence rate after AED withdrawal was 8.08 (P<0.00001) compared with the normal EEG patients, and there was no heterogeneity (P=0.29). The funnel chart shows that the partial seizures type subgroup analysis revealed positive results, while the not partial seizure group analysis reported negative results, indicating publication bias.

CONCLUSIONS

The risk of epilepsy recurrence is higher in children with abnormal EEG after AED withdrawal, regardless of seizure type. For pediatric epilepsy patients with abnormal EEG after AED withdrawal, a more cautious discontinuation regimen, closer follow-up and monitoring are required.

Recurrence rates and risk factors for seizure recurrence following antiseizure medication withdrawal in adolescent patients with genetic generalized epilepsy

Objective

This study aimed to identify the recurrence rate of genetic generalized epilepsy (GGE) and risk factors for recurrence after antiseizure medication (ASM) withdrawal in adolescent patients.

Methods

We retrospectively reviewed medical records of patients with GGE who were included in the registry at the Department of Child Neurology, National Hospital Organization Nishiniigata Chuo Hospital from 2000 through 2020. The eligibility criteria were as follows: onset of epileptic seizures at <15 years of age, treatment with an ASM, and attempted treatment withdrawal at 10‐19 years of age. The rates of seizure recurrence after drug withdrawal were evaluated. Moreover, several variables were evaluated as predictors of recurrence.

Results

In total, 77 patients with GGE (21, 13, and 43 patients with juvenile myoclonic epilepsy [JME], juvenile absence epilepsy [JAE], and epilepsy with generalized tonic–clonic seizures alone [EGTCSA], respectively) were included in this study. Recurrence was detected in 68% of patients with GGE (86%, 31%, and 70% of patients with JME, JAE, and EGTCSA, respectively). Recurrence rates for patients who developed epilepsy at ≥13 years of age, those who started dose reduction at ≥16 years of age, those who exhibited a seizure‐free period of <36 months before withdrawal, and those who chose to discontinue treatment at their own discretion were significantly higher than those for their counterparts. Multivariate analysis revealed that initiation of dose reduction at ≥16 years of age was associated with increased recurrence risk. Meanwhile, a diagnosis of JAE was associated with decreased recurrence risk. All patients with JAE were treated with valproic acid.

Significance

Antiseizure medication withdrawal at ≥16 years of age and a diagnosis other than JAE may be independent risk factors for seizure recurrence after drug withdrawal in adolescent patients.

Spike wave characteristics and temporal spike evolution on serial EEG in childhood epilepsy with centrotemporal spikes

PURPOSE

To assess the spike characteristics and temporal spike evolution on serial EEG of children with childhood epilepsy with centrotemporal spikes (CECTS) treated with anti-seizure medication.

METHODS

The study cohort consisted of 127 children with CECTS divided into three groups based on anti-seizure medication responsiveness: group I: seizure-free with monotherapy (n: 61, 48%), group II: seizure-controlled with monotherapy (n: 52, 41%) and group III: seizure-controlled with dual therapy (n: 14, 11%). The clinical profiles and sequential four-year follow-up visual EEG recordings of the children were evaluated. Each EEG was reanalyzed with three spike characteristics on the epochs: (1) spike-wave rate, (2) spike topography, and (3) spike localization. We calculated the spike clearance velocity, which is defined as a decrease in the spike-wave rate over time in four-year sequential follow-up EEGs.

RESULTS

There was no statistical significance across the study groups with respect to initial EEG spike characteristics (spike-wave rate, spike localization, and spike topography). Seizure recurrence occurred in 15 patients (12.8%) who discontinued anti-seizure medication. There was no statistically significant difference between the spike characteristics on EEG just before the discontinuation of anti-seizure medication and seizure recurrence. However, the spike clearance velocity was significantly slower in group III than in group I in four-year sequential follow-up EEGs (p = 0.002). A statistically significant decrease in the mean spike-wave rate was observed in group I in the first year of anti-seizure medication (p<0.001). The spike clearance velocity was also more prominent during the second year of treatment in group II and the third year of treatment in group III. However, the spike clearance velocity was not different across the anti-seizure medication groups (oxcarbazepine, valproic acid, and levetiracetam).

CONCLUSION

Spike clearance velocity might be a valuable EEG marker to guide anti-seizure medication in children with CECTS.