Prognosis after therapy discontinuation in children with epilepsy

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.

Rapid versus slow withdrawal of antiepileptic monotherapy in two-year seizure-free adults patients with epilepsy (RASLOW) study: A pragmatic multicentre, prospective, randomized, controlled study

PURPOSE

To establish whether a slow or a rapid withdrawal of antiepileptic monotherapy influences relapse rate in seizure-free adults with epilepsy and calculates compliance and differences in the severity of relapses, based on the occurrence of status epilepticus, seizure-related injuries, and death.

METHODS

This is a multicentre, prospective, randomized, open label, non-inferiority trial in people aged 16 + years who were seizure-free for more than 2 years. Patients were randomized to slow withdrawal (160 days) or rapid withdrawal (60 days) and were followed for 12 months. The primary outcome was the probability of a first seizure relapse within the 12-months follow-up. The secondary outcomes included the cumulative probability of relapse at 3, 6, 9, and 12 months. A non-inferiority analysis was performed with non-inferiority margin of - 0.15 for the difference between the probabilities of seizure recurrence in slow versus rapid withdrawal.

RESULTS

The sample comprised 48 patients, 25 randomized to slow withdrawal and 23 to rapid withdrawal. Median follow-up was 11.9 months. In the intention-to-treat population, 3 patients in the slow-withdrawal group and 1 in the rapid withdrawal group experienced seizure relapses. The corresponding probabilities of seizure recurrence were 0.12 for slow withdrawal and 0.04 for rapid withdrawal, giving a difference of 0.08 (95% CI - 0.12; 0.27), which is entirely above the non-inferiority margin. No patients developed status epilepticus and seizure-related injuries or died. Risks were similar in the Per-Protocol population.

CONCLUSIONS

Seizure-relapse rate after drug discontinuation is lower than in other reports, without complications and unrelated to the duration of tapering.

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.

Risk of seizure relapse after antiepileptic drug withdrawal in adult patients with focal epilepsy

OBJECTIVE

The objective of this study was to estimate the risk of a seizure relapse and the high-risk period of recurrence after antiepileptic drug (AED) withdrawal and to determine the predictive factors for a seizure relapse in adult patients with focal epilepsy who were seizure-free for more than 2years.

METHODS

Using the Wenzhou Epilepsy Follow-Up Registry Database, 200 adult patients with focal epilepsy were recruited, who were undergoing follow-up, met the inclusion criteria of this study, were seizure-free for more than 2years, began withdrawing between June 2003 and June 2014, and were followed up prospectively for at least 1year or until a seizure relapse. The risk of recurrence and the time to seizure relapse were analyzed by the Kaplan-Meier method, and the predictive factors were identified by the Cox proportional hazard regression model.

RESULT

A total of 99 patients had an unprovoked relapse during the follow-up period. The relapse rate was 49.5%, and each year, the recurrence probability of 12, 24, 36, 48, 60, 72, and 84months after AED withdrawal was 24.0%, 20.4%, 8.3%, 2.7%, 4.6%, 0.97%, and 0.98%, respectively. The two independent risk factors for recurrence after withdrawal in adult patients with focal epilepsy were a longer duration of active epilepsy and a shorter seizure-free period before withdrawal.

CONCLUSION

The high-risk period of a seizure relapse in adult patients with focal epilepsy is the first 2years after withdrawal, and beyond 5years after withdrawal, seizures rarely relapse (relapse rate<1%). A seizure-free period for less than 4years before withdrawal is a predictive factor of risk for seizure recurrence after AED withdrawal in adult patients with focal epilepsy.

Rapid versus slow withdrawal of antiepileptic monotherapy in 2-year seizure-free adult patients with epilepsy (RASLOW) study: a pragmatic multicentre, prospective, randomized, controlled study

Antiepileptic drug withdrawal may be an option for patients who have been seizure free for some years. The best withdrawal rate is questionable; in particular, it is unknown whether "rapid" withdrawal is associated with a higher risk of relapse as compared to "slow" withdrawal. We aim to establish if a slow or a rapid withdrawal schedule of antiepileptic monotherapy influences relapse rate in adult patients with focal or generalized epilepsy who have been seizure free for at least 2 years. This multicentre, prospective, randomized controlled study will enroll adult patients with focal or generalized epilepsy, who are seizure free on monotherapy. Patients will be randomized to a slow (160 days) or a rapid (60 days) schedule. Follow-up will last 1 year after randomization. The primary endpoint is the time to seizure relapse; secondary endpoints are compliance to the assigned schedule, occurrence of status epilepticus, of seizure-related injuries and mortality. A sample size of 350 patients has been planned. Univariate and multivariate analysis by Kaplan-Meier curves and Cox regression (primary endpoint) and by logistic regression (secondary endpoint) will be performed. The present study should contribute to better define the best withdrawal period for AED treatment in adult patients with epilepsy.

Antiepileptic drug withdrawal in childhood epilepsy: what are the risk factors associated with seizure relapse?

BACKGROUND

In recent years, several studies have been conducted to determine the risk of relapse after antiepileptic drug (AED) withdrawal: there is no general agreement on criteria that can predict safe discontinuation or seizure recurrence.

AIMS

To evaluate prospectively the relapse rate of epilepsy associated to AED withdrawal in epileptic children and to determine the risk factors of seizure recurrence.

METHODS

One hundred-sixty-eight children with epilepsy who were seizure-free for at least 2 years were enrolled and all children were proposed to stop AED treatment and were followed. In all children electroencephalograms (EEGs) were performed before the withdrawal of AEDs and after discontinuation of the treatment.

RESULTS

A total of 48 (28.6%) children relapsed; half of these patients relapsed while reducing the AED dose and the other half after the AED was withdrawn; after 2 years without AEDs, the risk of relapse was very low. Data evaluated by multivariable analysis showed that the children receiving polytherapy before AED withdrawal, having a history of febrile seizures and suffering from multiple seizure types relapsed more frequently. The presence of abnormal post-withdrawal EEG recordings was associated with a higher risk of seizure recurrence.

CONCLUSIONS

Epileptic children, after a seizure-free period of 2 years, have a low risk of seizure recurrence. The potential risk factors of relapse, are multiple seizure types previous polytherapy, history of febrile seizures and abnormalities in post-withdrawal EEG.

Evaluating the rate of recurrence of epilepsy after therapy discontinuation in 2-year seizure-free epileptic patients

INTRODUCTION

The potential complications of antiepileptic drugs render them risky and associated with numerous morbidities for long-term therapy. Therefore, it is essential to balance therapy discontinuation against risks of epilepsy recurrence. However, the risk factors predicting recurrence are yet to be identified. The present study was conducted in order to determine the rate of recurrence after gradual therapy discontinuation as well as its influential factors in epileptic patients under medical therapy who were seizure-free for a period of 2 years.

METHOD AND MATERIALS

This is a descriptive cross-sectional study on epileptic patients who referred to the specialized neurology clinic of Kermanshah University of Medical Sciences from 1994 to 2010. The data were extracted from patients' medical records and analyzed.

FINDINGS

A total of 391 patients were evaluated. In our study, 51.2% of patients experienced recurrence of seizure at the end of the 2-year follow-up. Recurrence occurred most frequently during medication tapering (51%). While the largest number of patients were aged under 12 years (178 patients; 45%), the rate of recurrence was greatest for patients aged 20-40 years (43 patients; 66.2%).

DISCUSSION AND CONCLUSION

As our findings suggest, type of epilepsy, multidrug therapy, abnormal electroencephalography before discontinuation, and abnormal brain computed tomography scan are factors that influence the risk of recurrence after therapy discontinuation. It is essential for the physician to take these factors into account and weigh the risk of recurrence against the benefits of therapy discontinuation.

Cerebral palsy, developmental delay, and epilepsy after neonatal seizures

This study sought to identify clinical prognostic factors for cerebral palsy, global developmental delay, and epilepsy in term infants with neonatal seizures. We completed a retrospective analysis of 120 term infants who experienced clinical neonatal seizures at a single academic pediatric neurology practice. Logistic regression analysis determined the significant independent prognostic (P < 0.05) indicators of cerebral palsy, global developmental delay, and epilepsy. Fifty-four (45%) infants were never diagnosed with a neurodevelopmental abnormality, whereas 37 (31%) manifested cerebral palsy, 51 (43%) manifested global developmental delay, and 38 (32%) manifested epilepsy. Global developmental delay was present in 92% of the children who manifested spastic quadraparetic cerebral palsy. Seizure type, seizure onset, electroencephalographic background findings, and 5-minute Apgar scores constituted independent predictors of cerebral palsy. None of the children who manifested less than two predictors developed the disorder. For global developmental delay, predictors included method of delivery, seizure onset, electroencephalographic background findings, and etiology. Only one infant (2%) who manifested less than two predictors exhibited global developmental delay. For epilepsy, predictors included seizure type and administration of a second antiepileptic drug. Only one infant (3%) who manifested neither predictor developed the disease.

Determination of risk factors associated with seizure relapse after antiepileptic drug withdrawal

There is no consensus regarding the time of antiepileptic drug withdrawal and the relevant risk factors for seizure relapse. In this study, we aimed to determine the seizure relapse rates and the associated risk factors for seizure relapse in childhood epilepsy. Two-hundred sixty-six epileptic patients who discontinued the antiepileptic drug therapy after a seizure-free period of at least two years, were enrolled into the study. The data of the patients regarding sex, febrile convulsion history, family history, age at onset, type of epilepsy, total number of seizures and antiepileptic drugs, seizures during treatment, mental status, first and last electroencephalography, brain imaging findings, etiological factors and seizure relapse in the first two years after antiepileptic drug withdrawal were obtained from the patients’ files. Univariate logistic regression analysis was performed for each variable. The variables which were found to be statistically significant in univariate analysis, were included in multivariate logistic regression analysis. The overall seizure relapse rate after antiepileptic drug withdrawal was 19.2%. There were no significant differences for seizure relapse rate after antiepileptic drug withdrawal between patient groups with respect to sex, family history, type of epilepsy, febrile convulsion history, seizures before treatment, first electroencephalography findings, brain imaging findings and etiology. However, there were statistically significant differences for seizure relapse rate among patient groups concerning age at onset of epilepsy, new seizure during treatment, the total number of antiepileptic drugs, mental status, and last electroencephalography findings. We imply that the clinical status of the patients should be considered before the cessation of drug therapy rather than the etiological factors or laboratory findings.

Recurrence risk after withdrawal of antiepileptic drugs in children with epilepsy: a prospective study

AIM

To study recurrence risk after withdrawal of antiepileptic drugs in children with epilepsy.

METHODS

All children younger than 14 with two or more unprovoked seizures 24h apart who were seen at our Hospital between 1994 and 2004 were included consecutively and prospectively followed. Patients previously examined in other centres were excluded. All patients who entered a remission were proposed to stop medication and were followed.

RESULTS

Three hundred and fifty three children with two or more unprovoked seizures were attended. A total of 238 entered a remission period and were proposed to stop medication, 216 accept. Mean seizure-free time before medication withdrawal was 2.2 years. Kaplan-Meier estimate of recurrence risk was 23% at 2 years (95% CI: 17-29) and 28% at 5 years (95% CI: 22-34). A remote symptomatic etiology, various seizure types and a history of prior febrile seizures or prior neonatal seizures were associated with a significant increase in recurrence risk in univariable and multivariable analyses using Cox proportional hazards model. Recurrence risk at 2 years was 17% (95% CI: 11-23) for idiopathic/cryptogenic epilepsies and 41% (85% CI: 28-54) for remote symptomatic epilepsies. Recurrence risks at 2 years by epileptic syndrome were West syndrome (0%), benign rolandic epilepsy (10%), epilepsy without unequivocal partial or generalized seizures (11%), benign infantile seizures (13%), absence epilepsy (16%), cryptogenic partial epilepsies (20%), symptomatic partial epilepsies (45%), symptomatic generalized epilepsies (54%).

CONCLUSIONS

Recurrence risk after withdrawal of antiepileptic treatment in children is low. Etiology and syndromic diagnosis are the main predictive factors.

Management of dental patients with seizure disorders

Dental practitioners from time to time must treat patients with epilepsy or similar seizure disorders. This article describes the various classification for epilepsy, explains how such disorders are evaluated and diagnosed, discusses management methods, and addresses related issues for special populations, such as pregnant women and elderly. In addition, the article offers information about what special steps dentists should take in treating such epileptic patients and others vulnerable to seizures and in preparing offices and staff for the possibility that a patient will have a seizure in the office. In general, a patient with severe, poorly controlled epilepsy should be treated in a hospital. Otherwise, a well-controlled patient should easily be treated in the office.

Should antiepileptic drugs be withdrawn in seizure-free patients?

Discontinuation of antiepileptic drug (AED) treatment is a valuable option in patients with epilepsy who have been seizure free for 2 years or longer. However, the decision to withdraw AEDs must be based on a balanced view of the overall risk of seizure relapse, the factors most likely to affect that risk, and the medical, emotional and social implications of treatment continuation versus treatment withdrawal. In a critical review of 28 studies accounting for 4571 patients (2758 children, 1020 adults and a combined group of 793), most with at least 2 years of seizure remission, the proportion of patients with relapses during or after AED withdrawal ranged from 12 to 66%. Using life-table analysis, the cumulative probability of remaining seizure-free in children was 66-96% at 1 year and 61-91% at 2 years after withdrawal of AEDs. The corresponding values in adults were 39-74% and 35-57%, respectively. The relapse rate was highest in the first 12 months (especially in the first 6 months) after withdrawal and tended to decrease thereafter. Based on a previously published meta-analysis of data published up to 1992, the pooled relapse risk was 25% (95% CI 21, 30%) at 1 year and 29% (95% CI 24, 34%) at 2 years after AED withdrawal. The factors associated with a higher-than-average risk of seizure relapse included adolescent-onset epilepsy, partial seizures, the presence of an underlying neurological condition, and abnormal EEG findings at the time of AED withdrawal in children. Factors associated with a lower-than-average risk were childhood-onset epilepsy, idiopathic generalised epilepsy and - for children - a normal EEG. Selected epilepsy syndromes (e.g. benign epilepsy with centrotemporal spikes and juvenile myoclonic epilepsy) may be associated with significantly different outcomes after AED withdrawal. All these factors and their combinations may contribute to the development of guidelines for practising physicians to help them in making the best decision related to treatment discontinuation. The decision plan should also take into account social factors (driving license, job and leisure activities) as well as emotional and personal factors, and must be tailored to and discussed with the individual patient and his/her family.

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.

Meta-analysis of EEG test performance shows wide variation among studies

BACKGROUND

EEG results are used for counseling patients with seizures about prognosis and deciding on medications. Published sensitivities of interictal EEG vary widely.

OBJECTIVE

To account for variation in test characteristics between studies.

METHODS

Meta-analysis. Medline search, 1970 to 2000, of English language studies. Standard methods for meta-analysis of diagnostic test performance were used to determine the ability of EEG results to distinguish between patients who will and will not have seizures. Using linear regression, the authors assessed the influence of readers' thresholds for classifying the EEG as positive, sample probability of seizure, percent of subjects with prior neurologic impairment, percent treated, and years followed.

RESULTS

Twenty-five studies involving 4,912 EEG met inclusion criteria. Specificity (range 0.13 to 0.99) and sensitivity (range 0.20 to 0.91) of epileptiform EEG interpretations varied widely and were heterogeneous by chi(2) analysis (p < 0.001 for each). Diagnostic accuracy of EEG and the thresholds for classifying EEG as positive varied widely. In the multivariate model, differences in readers' thresholds accounted for 37% of the variance in EEG diagnostic accuracy, and no other reported factors were significant.

CONCLUSION

This analysis suggests that there is wide interreader variation in sensitivity and specificity of EEG interpretations, and that this variation influences the ability of EEG to discriminate between those who will and will not have seizure recurrences. In clinical practice, interpreting the degree to which a positive EEG result predicts increased seizure risk in an individual patient is difficult. Interpreting EEG with higher specificity yields more accurate predictions.

Risk factors for recurrence of epilepsy and withdrawal of antiepileptic therapy: a practical approach

In epileptic patients, treated with anticonvulsant drugs (AEDs), the question when and how an attempt should be made to withdraw therapy is a crucial point in the management of these patients. In recent years, many studies have identified the main risk factors for seizure recurrence after discontinuation of AEDs. Patients are more likely to have recurrences if there is a definite symptomatic aetiology, two or more different types of seizures, an abnormal neurological examination and a seizure onset at adolescence or later. In contrast, abnormal EEG has not been proved as a risk factor for recurrence. Moreover, the classification of epilepsy syndromes is another important predictor of the outcome for these patients. In practice, most authors suggest that medication is discontinued after a seizure-free period of two years. In this review we analyse data from the literature and we suggest a practical approach for safe anticonvulsant withdrawal, although the decision should always be made individually, weighing risks and benefits.

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.

Discontinuing anti-epileptic medication(s) in epileptic children: 18 versus 24 months

For a period of slightly over 4 years, 80 children who had been seizure-free for at least 18 months while on anti-convulsant medication were prospectively collected. These 80 children were randomly assigned to either the 18-months seizure-free group (n = 41) or to the group where anti-convulsant medications were continued for another 6 months before they were gradually tapered off and stopped, i.e. the 24-months seizure-free group (n = 39). Twelve (29%) of the 41 children who had been seizure-free for 18 months and 14 (36%) of the 39 children who had been seizure-free for 24 months had seizure recurrence during the follow-up period. Log-rank test of the recurrence experience of the two groups of patients showed no statistically significant difference between the groups (p > 0.50). Similarly, when both groups were combined and other risk variables likely to influence the rate of seizure recurrence were tested, only EEG abnormality at discontinuation of anti-convulsant medication had a significant association with the risk of seizure recurrence (p < 0.001).

Seizure recurrence and risk factors after withdrawal of chronic antiepileptic therapy in children

The aim of this study was to identify the risk factors for seizure recurrence after withdrawal of chronic antiepileptic therapy in 226 children: 136 with partial epilepsies and 90 with generalized epilepsies. The influence on prognosis of the different variables was assessed retrospectively with univariate and multivariate analysis. With a mean observation period of 5.85+/-3.87 years, seizure recurrence occurred in 24.3% of all patients with partial and generalized epilepsies. In children with partial epilepsies, the following factors were found to significantly increase relapse risk after treatment withdrawal: neurological abnormalities; interval between seizures less than 1 month at onset of illness; the use of VPA in treating seizures; start of withdrawal after 6 years of age; frontal paroxysmal activity; and abnormal EEG before drug withdrawal. In children with generalized epilepsies the risk factors were found to be: abnormal neonatal period; first seizure after 10 years of age; mean duration of seizures greater than 1 minute; poor school progress and generalized spike-waves in EEG. The factors associated with the risk of recurrence in children with generalized epilepsy appear to differ from to those related to partial epilepsies, in which seizure treatment with VPA was associated with an increased recurrence risk after the withdrawal of antiepileptic drugs.

Established antiepileptic drugs

Despite the recent entry into the market-place of a range of new pharmacological treatments for epilepsy, most patients still receive the standard antiepileptic drugs. This review considers the clinical place and practical use of these agents. Detailed consideration is given to carbamazepine, phenytoin, sodium valproate, phenobarbital and ethosuximide, with lesser emphasis on primidone, clobazam and clonazepam. Individualization of therapy, polypharmacy, refractory epilepsy, therapeutic drug monitoring, pregnancy, withdrawing treatment, epilepsy prophylaxis and referral to an epilepsy centre are also discussed. The paper concludes with a statement of 12 basic rules in prescribing established antiepileptic drugs.

Early discontinuation of treatment in children with uncomplicated epilepsy: a prospective study with a model for prediction of outcome

PURPOSE

The main purpose of the present study was to identify predictor variables with significant influence on seizure outcome after discontinuation of treatment in children with uncomplicated epilepsy and to analyze whether these variables, included in a prognostic model could identify children in whom 1-year treatment would be sufficient.

METHODS

Before initiation of treatment in children aged 2-16 years with uncomplicated epilepsy, the duration of treatment was randomized to 1 year (group I) or 3 years (group II). At the end of the allotted period, treatment was discontinued in 161 children who had been seizure fre during the previous 6 months. The mean follow-up period after treatment was 5.8 years. Twenty-three predictor variables were analyzed by survival methods regarding their influences on the outcome.

RESULTS

At the latest follow-up check, 60 children (37%) had relapsed. The following predictor variables were selected by multiple regression analysis and constituted a model with a simple scoring system: age at seizure onset; seizure type; generalized, irregular spike-wave activity on EEG after 1 year of treatment; and persistent 3-Hz spike-wave activity after 6 months of treatment in children with absence epilepsy. In group I, the remission rate was 73% in children with high prognostic scores, 10% in children with low scores, and 40% in those with intermediate scores (log-rank test, p = 0.0001).

CONCLUSIONS

After 1 year of treatment, our prognostic model identified children in whom treatment could be withdrawn at that time. Our model should be easily applicable in clinical practices and may be of clinical importance in determining the duration of treatment in children with uncomplicated epilepsy.

A comparison between one and three years of treatment in uncomplicated childhood epilepsy: a prospective study. II. The EEG as predictor of outcome after withdrawal of treatment

PURPOSE

We wished to evaluate the prognostic usefulness of various EEG parameters with respect to remission rates after discontinuation of antiepileptic drug (AED) therapy in children treated for epileptic seizures.

METHODS

Two hundred forty-four children with uncomplicated epileptic seizures were randomized to either 1 or 3 years of treatment with AEDs. The treatment was then discontinued in patients who had been seizure-free during the last 6 months of their allotted time of treatment (n = 154). After treatment discontinuation, the children were followed for at least 2 years. EEG recordings were performed before treatment was initiated and at regular intervals during treatment.

RESULTS

The overall relapse rate was 37%. In many children, the amount of epileptiform activity varied considerably between subsequent recordings made during the treatment. The remission rate was slightly higher for children whose last recordings before AED discontinuation were free of epileptiform activity as compared with children in whom such activity was present. However, children who had irregular generalized spike-wave (SW) activity in the recordings made before discontinuation of treatment had a clearly higher relapse rate (67%) both as compared with children without epileptiform activity (33%) and as compared with children with other types of epileptiform activity (33%) in their last EEG recordings before discontinuation. All children treated for only 1 year whose final EEGs displayed generalized irregular SW activity relapsed.

CONCLUSIONS

We conclude that the presence of epileptiform activity does not in itself necessarily influence prognosis after discontinuation of treatment but that certain types of such activity signal a high risk of relapse.

Comparison between one and three years of treatment in uncomplicated childhood epilepsy: a prospective study. I. Outcome in different seizure types

PURPOSE

The main purpose of this prospective study was to analyze whether 1 year of treatment was as effective as 3 years with respect to remission rate in children with idiopathic epilepsy.

METHODS

Treatment for epileptic seizures was started in 207 children aged 2-16 years. They were randomized to treatment for 1 or 3 years. At the end of the predetermined treatment period, 161 children had been seizure-free for 6 months and the treatment could be gradually withdrawn.

RESULTS

The overall remission rate in our group of patients was significantly higher (71%) in the group treated for 3 years than in the group treated for 1 year (53%). However, comparison of remission rates between patients with different seizure types showed statistically significant differences in outcome depending on duration of treatment only in children with complex partial seizures (CPS).

CONCLUSIONS

Our results show that 1 year of treatment can be recommended in children with benign partial epilepsy with rolandic spikes (BECT) and in children with simple partial seizures (SPS) but is clearly insufficient in children with CPS. A proper seizure classification is one important tool, although not sufficient, in offering recommendations concerning the duration of treatment in children with idiopathic epilepsy.

Discontinuation of anti-epileptic therapy: a retrospective study of 86 children and adolescents

In order to identify any predictive factors of relapse after the discontinuation of anticonvulsive therapy, a catamnestic study was made of 86 epileptic children and adolescents who had started or completed the withdrawal of AEDs. Their clinical records were examined retrospectively, and univariate analysis showed that the factors which correlated significantly with a higher relapse rate were the age at the time of reducing treatment, the presence of more than 30 generalised or partial tonic-clonic seizures, the presence of febrile seizures, the duration of the active phase of the disease, the duration of therapy, and the coexistence of more than one type of seizure. At multivariate analysis, only the presence of 30 generalised or partial tonic-clonic seizures and febrile seizures were significant. Given the small size of the diagnostic subgroups, no significant correlation could be demonstrated between epileptological diagnosis and the risk of recurrence.

Factors predicting the risk of relapse after antiepileptic drug discontinuation in children with partial seizures

The purpose of this study is to identify possible factors which could influence the seizure recurrence after anti-epileptic drug (AED) withdrawal in children with partial epilepsy. AED was discontinued in 82 children who had been free of partial epileptic seizures for 2.0-11.0 years (mean 4.7 years). Twenty-four patients (29.3%) had a relapse from a few days to 6.1 years (mean 1.2 years) after AED discontinuation. Significantly more common in children who relapsed were: younger age at beginning of AED withdrawal, occurrence of complicated febrile convulsions (5/24 vs 1/58, P < 0.01), abnormal neurological examination (8/24 vs 8/58, P < 0.05), delayed psychomotor development (7/24 vs 7/58, P < 0.05), focal slowing (6/24 vs 3/58, P < 0.01) and focal epilepti-form discharges (7/24 vs 6/58, P < 0.05) in the last EEG before AED discontinuation. Between the two groups no statistical significant differences concerning the age at onset of seizures, the duration at AED therapy after the last seizure, the familial occurrence of epilepsy and background EEG abnormalities in the last EEG before AED discontinuation were found. On the basis of EEG, occurrence of febrile convulsions, and neurological and developmental examination it may be possible to predict which children have the best chance to remain free of recurrence after AED discontinuation.

Discontinuing antiepileptic drugs in children with epilepsy. A comparison of a six-week and a nine-month taper period

BACKGROUND

The optimal regimen for discontinuing antiepileptic medications in children with epilepsy is unknown.

METHODS

We randomly assigned 149 children to either a six-week or a nine-month period of drug tapering, after which therapy was discontinued. Each group was composed of patients who had been seizure-free for either two or four years before drug tapering was begun. Most patients were receiving one antiepileptic drug; none were taking more than two. The children were evaluated periodically during and after the taper period. Sixteen patients were lost to follow-up before the beginning of the taper period. Proportional-hazards regression analysis was used to assess the risk of seizure recurrence among the remaining 133 patients.

RESULTS

Seizures recurred in 53 patients (40 percent). The mean duration of follow-up was 39 months (range, 11 to 105) for the patients who did not have a recurrence of seizures. Neither the length of the taper period (six weeks vs. nine months, P = 0.38) nor the length of time the patients were free of seizures before the taper period was begun (two years vs. four years, P = 0.20) significantly influenced the risk of seizure recurrence. The presence of mental retardation (relative risk, 3.1, 95 percent confidence interval, 1.5 to 6.2) or spikes in the electroencephalogram at the time of tapering (relative risk, 1.9, 95 percent confidence interval, 1.0 to 3.4) increased the risk of seizure recurrence.

CONCLUSIONS

The risk of seizure recurrence during drug tapering and after the discontinuation of antiepileptic drug therapy in children with epilepsy is not different whether the medications are tapered over a six-week or a nine-month period.

Drug withdrawal in patients with epilepsy: prognostic value of the EEG

The role of the inter-ictal EEG in predicting seizure relapse after antiepileptic drug withdrawal (AED-W) is unclear. A prospective study on AED-W is in progress. This trial includes routine and sleep EEG recordings every 3 and 6 months, respectively, at each step of the drug discontinuation and periodically during follow-up. Data obtained for 136 patients (mean age 23.2 years; 63 with Idiopathic Generalized Epilepsy IGE, 73 with Partial Cryptogenic or Symptomatic Epilepsy PE; without associated neuropsychiatric handicap; with at least 1 year of follow-up after AED-W) were analysed. EEG recordings from seizure onset were available for all patients. Data were analysed separately in IGE and PE patients. The presence of inter-ictal epileptiform abnormalities (IEAs) at the seizure onset and just before AED-W does not seem to predict the AED-W outcome. However, results indicate an association between persisting and increased IEAs during AED-W and a higher relapse rate in both groups, which was statistically significant in the IGE patients.