Withdrawal of antiepileptic drug treatment in childhood epilepsy: factors related to age

Risk of recurrence after antiepileptic withdrawal: Was it a good decision or not?

Background: The aim of this study was to identify the demographic-clinical variables affecting idiopathic epilepsy (IE) [called genetic generalized epilepsy (GGE)] recurrence and determine cut-off values that can be used in pediatric neurology practice for children with IE/GGE. Methods: A total of 250 children and adolescents with IE/GGE were included and retrospectively evaluated. The patients' hospital records were examined in order to identify possible electro-clinical features affecting epilepsy recurrence. Results: The overall rate of recurrence in the patients was 46%; the age at onset of seizures in recurrence group was lower (P = 0.040) and the age at last seizure was higher in the recurrence group (P < 0.001) than that in the non-recurrence group. Other factors found to be related to recurrence were the shorter duration of the seizure-free period (P = 0.030), shorter interval between the last seizure and antiepileptic drug (AED) withdrawal (P = 0.003), shorter duration of AED withdrawal (P = 0.005), and the existence of abnormalities on sleep electroencephalogram (EEG) during AED withdrawal (P = 0.010) and at the 6th month of withdrawal (P < 0.001). According to receiver operating characteristic (ROC) analysis, the risk of IE recurrence was higher in children who were younger than 3.6 years old (sensitivity: 65.6%, specificity: 62.7%), children with a seizure-free period that was shorter than 35.5 months (sensitivity: 89.6%, specificity: 32.8%), and children whose drug withdrawal period was shorter than 4.5 months (sensitivity: 56.3%, specificity: 71.6%). Conclusion: This study defined some electro-clinical factors that could guide clinicians when deciding to withdraw AEDs with regard to recurrence risk after evaluating a homogenous population of children with a diagnosis of IE/GGE.

Can electroencephalograms provide guidance for the withdrawal of antiepileptic drugs: A meta-analysis

OBJECTIVE

The discontinuation of antiepileptic drugs (AEDs) is an important treatment decision for epilepsy patients who have been seizure-free for 2years or longer. Some patients experience seizures relapse after AED withdrawal. The prognostic value of electroencephalograms (EEGs) for seizure relapse following AED withdrawal is controversial. To our knowledge, this is the first meta-analysis to address whether EEG data can be used to guide the discontinuation of AEDs.

METHOD

We performed a meta-analysis of cohort studies that reported original EEG data from before AED withdrawal and recurrence after AED-withdrawal. The quality of each study was assessed using the Newcastle-Ottawa Scale.

RESULTS

Fifteen studies including a total of 2349 participants were included in this meta-analysis. This meta-analysis of 15 studies demonstrates that an abnormal electroencephalogram was a predictor of the risk of relapse. Additionally, paroxysmal, slowing, spike and wave activities on electroencephalograms were associated with increased risk of relapse.

CONCLUSION

We reveal that abnormal EEG records, particularly paroxysmal abnormalities, before AED withdrawal predicted a high risk of relapse. Slowing and spike and wave activities also exhibited moderate predictive values.

SIGNIFICANCE

Our findings suggest that, EEGs might be an important prognostic tool for antiepileptic drug reduction.

Cryptogenic localization-related epilepsy with childhood onset: The problem of definition and prognosis

BACKGROUND

Up to one-third of children with epilepsy are diagnosed with cryptogenic localization-related epilepsy (CLRE). CLRE is a large nonspecific category within the ILAE classification. For this population no unequivocal prognosis exists.

METHODS

Twenty-five articles describing aspects of CLRE were included in this review.

RESULTS

As a result of the progress in epilepsy research, as well as more advanced investigation in individual cases, the population with CLRE constantly changes. Also, disagreement on interpretation of the classification has resulted in striking differences between the populations described. High remission rates are reported, but relapse occurs frequently, leaving the long-term prognosis unforeseeable. This is reflected in academic and psychosocial prognosis, which is described to be problematic in CLRE specifically. Possible prognostic factors of CLRE in children have been identified: age at onset, seizure semiology, seizure frequency, intractability, interictal epileptiform activity on EEG, and premorbid IQ. These factors are explored to define subgroups within the CLRE population.

DISCUSSION

Prospective studies on well-defined CLRE cohorts are needed to identify factors that distinguish various prognostic subgroups. Specific attention should be focused on course of the epilepsy, scholastic achievement, and psychosocial outcome.

Prognosis after withdrawal of antiepileptic drugs in childhood-onset cryptogenic localization-related epilepsies

The purpose of this study was to clarify the risk factors of relapse following discontinuation of AEDs in patients with childhood-onset cryptogenic localization-related epilepsies. The subjects were 82 patients who fulfilled the following criteria: (1) age at first visit of less than 15 years, (2) follow-up period of more than 5 years, (3) suffering from cryptogenic localization-related epilepsies, and (4) the patient underwent AED withdrawal during the follow-up period. As a basic principle, we decided to start withdrawing AEDs when both of the following two conditions were met: (1) the patient had a seizure-free period of 3 years or more, and (2) there were no epileptic discharges on EEGs just prior to the start of withdrawal. Seizures recurred in eight of the 82 patients (9.8%). Univariate analysis revealed that the following factors were correlated with higher rates of seizure relapse: 6 years of age or higher at onset of epilepsy; 15 years of age or higher at the start of AED withdrawal; 5 years or more from the start of AED treatment to seizure control; five or more seizures before seizure control; and two or more AEDs administered before seizure control. Among these risk factors, 6 years of age or higher at onset and 5 years or more from the start of AED treatment to seizure control were determined by multivariate analysis to be independent risk factors for relapse. Thus, we conclude that the physician should be more careful in discontinuing AEDs in these higher-risk patients groups, and more generous in discontinuing AEDs in lower-risk groups.

Antiepileptic drug withdrawal: literature review

Of patients with epilepsy, 60% to 70% achieve control with antiepileptic medication. Antiepileptic drugs may be associated with unwanted adverse effects, inconvenience, and cost. Remission may occur in some patients, raising the issue of whether continued treatment is necessary. Identifying patients from whom treatment can be withdrawn successfully would be beneficial on many levels, but selecting patients may be difficult. Several published antiepileptic drug withdrawal studies show variable rates of success, with relapse rates ranging from 12% to 63%. Several prognostic factors help identify patients who may be amenable to antiepileptic drug withdrawal. The results and limitations described in the antiepileptic drug withdrawal literature, prognostic factors, and general guidelines for antiepileptic drug withdrawal are presented in this article.

Predictive value of EEG monitoring during drug withdrawal in children with cryptogenic partial epilepsy

In order to evaluate the predictive value of the interictal EEG after discontinuation of anticonvulsant therapy in children with cryptogenic partial epilepsy, a prospective study was carried out on 84 children and adolescents who had been seizure-free for at least 2 years. Twenty-four children (28.6%) presented one or more relapses. EEG monitoring during drug withdrawal showed abnormalities in 67% of the patients (16/24) who relapsed with seizures, and in 10% of the patients (6/60) who did not relapse. Our study suggests that in children who have suffered from partial epilepsy, the detection of paroxysmal abnormalities during drug withdrawal, in a previously normal EEG is a risk factor for recurrence of seizures. It is therefore advocated that periodic EEG monitoring be carried out during the drug withdrawal period, because the presence of EEG abnormalities is associated with a high probability of seizures occurring during or after drug discontinuation.