Juvenile myoclonic epilepsy of Janz: clinical observations in 60 patients

Clinical Characteristics and Prognosis of Juvenile Myoclonic Epilepsy: Single-Center Retrospective Study

Juvenile myoclonic epilepsy (JME) is one of the most common idiopathic (genetic) generalized epilepsy syndromes. It occurs in healthy adolescents and is characterized by the triad of myoclonic jerks, generalized tonic-clonic seizures (GTCs), and absence seizures. The study's primary aim was to determine the demographic and clinical characteristics, family history of seizure, electroencephalogram findings, treatments, and short-term prognosis of patients diagnosed with JME. Patients diagnosed with JME at the Pediatric Neurology Department of Sağlık Bilimleri University Adana Numune Training and Research Hospitals were enrolled. Thirteen (30%) of 44 patients were male, whereas 31 (70%) were female, with a mean age at diagnosis of 14 ± 1.3 years. In total, 21 patients (48%) had a family history of epilepsy, and 14 patients (32%) had JME in their families. Those having a family history of JME seizures were identified at a younger age. Thirty (68%) patients presented with GTCs, while 14 (32%) presented with myoclonic seizures at the time of diagnosis. In the history, 98% of patients had myoclonus and one patient had an absence seizure. Patients with the first seizure type GTCs were diagnosed later, while patients with myoclonus were diagnosed earlier (p < 0,05). The most precipitating factors for seizures were sleep deprivation and stress. Thirty-eight (86%) of the EEGs recorded during the initial admission was abnormal. Valproic acid was administered to 32 patients (73%), while levetiracetam was administered to 12 patients (27%) as the initial treatment. Forty-one (93%) of the patients exhibited a complete response to the initial medication therapy, while forty (91%) of the patients received monotherapy, and only four (9%) received polytherapy. JME may be well-controlled epilepsy with early diagnosis and appropriate treatment. A family history of JME is also common among patients with JME. Patients with the myoclonus as a first seizure type are diagnosed earlier than GTCs because of family awareness. A family history of JME may facilitate the diagnosis of new cases in the family.

Isolated Unilateral EEG Findings in Juvenile Myoclonic Epilepsy: A Case Report

Juvenile myoclonic epilepsy (JME) has well-defined clinical and electrophysiological features. On the other hand, large case series have shown that focal and asymmetrical discharges may accompany generalized epileptiform activities in JME. Although it is known that these non-generalized electrophysiological findings do not exclude the diagnosis of this syndrome, some findings may create confusion in the differential diagnosis. In this case report, a case of JME with electroencephalographic findings characterized by isolated unilateral epileptiform activities without typical generalized discharges was discussed. The current case clinically presented with involuntary jerk movements in the bilateral upper extremities. It has been determined that these movements are uni/bilateral myoclonic beats based on home video recordings. Metabolic, toxic and structural problems were excluded in the investigations for the etiology of myoclonus. In the electrophysiological examination performed for epileptic processes, epileptiform discharges localized to the isolated right hemisphere were observed. JME was considered primarily due to clinical findings in the patient, and effective seizure control was achieved in a 4-year follow-up under anti-seizure treatment. The peculiarity of the case is the presence of electrophysiology recordings of isolated unilateral epileptiform activity during the 4-year follow-up period. It should be emphasized that there is no case of JME diagnosed with isolated unilateral epileptiform activity in the absence of generalized spike-slow waves or multiple spike-slow waves in the literature.

Seizure control in mono- and combination therapy in a cohort of patients with Idiopathic Generalized Epilepsy

Idiopathic Generalized Epilepsy (IGE) patients may not achieve optimal seizure control with monotherapy. Our goal was to evaluate the efficacy of combination therapy in a retrospective series of IGE patients receiving different antiseizure medication (ASM) regimens. We retrospectively identified all patients with adolescence onset IGE with typical clinical and EEG features from a single epilepsy specialist clinic from 2009 to 2020. We evaluated long-term seizure control, for VPA, LEV, LTG mono and combination therapy. We studied 59 patients. VPA was more commonly used in men (84%) than in women (44%) (p < 0.05). VPA was the initial drug of choice in 39% of patients, followed by LEV (22%) and LTG (14.9%). Thirty-nine patients (66.1%) achieved complete seizure control for at least one year. Fifty patients (84.7)% had partial control, without GTC occurrence, for at least one year. VPA was superior to LTG for complete seizure control (p = 0.03), but not for minor seizure control or pseudoresistance (p > 0.05). Combination therapy was superior to LEV and LTG monotherapy for complete control (p = 0.03), without differences for minor seizures and pseudoresistance outcomes (p > 0.05). Combination therapy not including VPA was also non-inferior to VPA monotherapy in all settings. Combination therapy was superior to LTG and LEV monotherapy in IGE, and may be equally effective including or not VPA. Combination therapy including LTG, LEV, and/or VPA is an effective treatment option after monotherapy failure with one of these ASM in IGE. Dual therapy with LEV-LTG should be considered in monotheraphy failure, to avoid fetal effects of in utero VPA exposure.

Diagnostic and therapeutic approach to drug-resistant juvenile myoclonic epilepsy

INTRODUCTION

Juvenile myoclonic epilepsy (JME), also known as Janz syndrome, is a common form of generalized epilepsy of presumed genetic origin representing up to 10% of all epilepsy cases. Despite adequate anti-seizure medication (ASM) treatment, seizures persist in one-third of JME patients.

AREAS COVERED

A literature search was conducted using Pubmed search on the topics of drug-resistant JME.

EXPERT OPINION

About 30% of JME patients are drug-resistant. Valproate (VPA) is considered the first-choice drug. In women of childbearing potential, levetiracetam (LEV) should represent the first-choice treatment. Alternative monotherapy or add-on therapy should be considered in subjects with resistant seizures after the exclusion of pseudo-drug resistance. The choice of the add-on ASM depends on the predominant seizure type. In subjects with persistent bilateral tonic-clonic seizures, LEV or lamotrigine should be firstly considered. In patients with difficult-to-treat myoclonic seizures, clonazepam or LEV are recommended. In case of persistent absences, ethosuximide should be considered. With appropriate selection and safeguards in place, VPA should remain available as an option in women of childbearing potential whose seizures are resistant to other treatments.

Trait impulsivity correlates with active myoclonic seizures in genetic generalized epilepsy

BACKGROUND

Juvenile myoclonic epilepsy (JME) is a common subtype of genetic generalized epilepsy (GGE) arising in adolescence and is often associated with executive function (EF) deficits. Some EF components like response inhibition have been extensively evaluated in JME, but few studies have focused upon trait impulsivity or compared between GGE subtypes. The aim of the present study was to compare the association of trait impulsivity in JME with other GGE subtypes.

METHODS

Patients with GGE aged between 14 and 40 years (n = 137) were divided into those with JME (n = 92) and those with other GGEs (n = 45: 8 childhood absence epilepsy (CAE), 22 juvenile absence epilepsy (JAE), and 15 epilepsy with generalized tonic-clonic seizures only (EGTCS)). The study participants were recruited through medical records of the general population of Buskerud County and the neighboring municipalities, covering 477,000 people or 9.1% of Norway's total population. All participants underwent a clinical interview including the Barratt Impulsiveness Scale (BIS), an established measure of trait impulsivity. We controlled for other potential predictors of BIS score using analysis of covariance (ANCOVA).

RESULTS

There were no differences between JME and other types of GGE for BIS scores, but the presence of myoclonic seizures within the last year, irrespective of GGE subtype, was independently associated with significantly increased behavioral impulsivity.

CONCLUSIONS

This study demonstrates that trait impulsivity in GGE is most strongly related to the recent occurrence of myoclonic seizures rather than GGE subtype.

Juvenile myoclonic epilepsy mimic associated with CHD2 gene mutation

This paper reports the electroclinical manifestations of an epilepsy syndrome associated with a chromodomain helicase DNA-binding protein 2 (CHD2) gene mutation with clinical semiology and electroencephalographic (EEG) features consistent with juvenile myoclonic epilepsy (JME). Myoclonic and myoclonic-tonic–clonic seizures, as well as generalized 4- to 5-Hz high-amplitude spike–wave and polyspike–wave discharges, were well characterized in an adolescent. However, the atypical age of onset, developmental disability, and apparent drug resistance led to suspicion of an alternative etiology for epilepsy, subsequently verified as a CHD2 gene mutation. When atypical features are present, a JME mimic should be suspected in the differential diagnosis of the more established syndrome of JME.

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Chromodomain helicase DNA-binding protein 2 (CHD2) mutation is associated with epilepsy.

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A juvenile myoclonic epilepsy phenotype with atypical history may be a mimic.

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Cases concerning for juvenile myoclonic epilepsy mimics should be considered for genetic testing.

Dealing with the storm: An overview of seizure precipitants and spontaneous seizure worsening in drug-resistant epilepsy

In drug-resistant epilepsy, periods of seizure stability may alternate with abrupt worsening, with frequent seizures limiting the individual's independence and physical, social, and psychological well-being. Here, we review the literature focusing on different clinical scenarios related to seizure aggravation in people with drug-resistant epilepsy. The role of antiseizure medication (ASM) changes is examined, especially focusing on paradoxical seizure aggravation after increased treatment. The external provocative factors that unbalance the brittle equilibrium of seizure control are reviewed, distinguishing between unspecific triggering factors, specific precipitants, and 'reflex' mechanisms. The chance of intervening surgical or medical conditions, including somatic comorbidities and epilepsy surgery failure, causing increased seizures is discussed. Spontaneous exacerbation is also explored, emphasizing recent findings on subject-specific circadian and ultradian rhythms. Awareness of external precipitants and understanding the subject-specific spontaneous epilepsy course may allow individuals to modify their lifestyles. It also allows clinicians to counsel appropriately and to institute suitable medical treatment to avoid sudden loss of seizure control.

Outcomes of low-dose valproic acid treatment in patients with juvenile myoclonic epilepsy

PURPOSE

There are conflicting data regarding the drug dose that is sufficient to achieve seizure control as well as the parameters of seizure remission in juvenile myoclonic epilepsy (JME). The present study aimed to identify factors that contribute to seizure control in JME and to evaluate factors associated with JME remission and the efficacy of low-dose valproic acid (VPA) therapy.

METHODS

This retrospective, cross-sectional study included a total of 215 patients (121 female and 94 male; mean age: 28.03 ± 8.43 [14-59] years) diagnosed with JME. The patients were divided into remission and refractory groups. Remission was defined as a seizure-free (myoclonic, absence, and/or generalized tonic-clonic) period of at least 2 years. Patients in whom remission was achieved with VPA monotherapy were further divided into two groups according to the use of low-dose VPA therapy (VPA ≤ 750 mg/day and >750 mg/day). Potential contributing factors were evaluated in terms of the relationship between the dose and the remission parameters.

RESULTS

Remission was achieved with VPA monotherapy in 116 patients (87.9%) in the remission group; the VPA dose was ≤750 mg in 77.6% of the patients. The dose of VPA was higher in patients with absence seizure who achieved remission (p = 0.026). Remission was achieved with a lower dose of VPA in females than in males (p = 0.004).

CONCLUSIONS

Low-dose VPA can be used to achieve remission in JME. However, identification at follow-up visits of the factors that may affect remission may change the planned effective dose of VPA.

Refractory juvenile myoclonic epilepsy: a meta-analysis of prevalence and risk factors

Background and purpose

Juvenile myoclonic epilepsy (JME) is a common epilepsy syndrome for which treatment response is generally assumed to be good. We aimed to determine the prevalence and prognostic risk factors for refractoriness of JME.

Methods

We systematically searched PubMed and EMBASE and included 43 eligible studies, reporting seizure outcome after antiepileptic drug (AED) treatment in JME cohorts. We defined refractory JME as persistence of any seizure despite AED treatment and performed a random‐effects meta‐analysis to assess the prevalence of refractory JME and of seizure recurrence after AED withdrawal in individuals with well‐controlled seizures. Studies reporting potential prognostic risk factors in relation to seizure outcome were included for subsequent meta‐analysis of risk factors for refractoriness.

Results

Overall, 35% (95% confidence interval, 29–41%) of individuals (n = 3311) were refractory. There was marked heterogeneity between studies. Seizures recurred in 78% (95% confidence interval, 52–94%) of individuals who attempted to withdraw from treatment after a period of seizure freedom (n = 246). Seizure outcome by publication year suggested that prognosis did not improve over time. Meta‐analysis suggested six variables as prognostic factors for refractoriness, i.e. having three seizure types, absence seizures, psychiatric comorbidities, earlier age at seizure onset, history of childhood absence epilepsy and praxis‐induced seizures.

Conclusion

One‐third of people with JME were refractory, which is a higher prevalence than expected. Risk factors were identified and can be used to guide treatment and counselling of people with JME.

Juvenile myoclonic epilepsy and sleep

Juvenile myoclonic epilepsy (JME) is a sleep-related epilepsy syndrome, and only a few studies have addressed the relationship between JME and sleep disorders. In this review, the sleep characteristics of patients with JME were summarized based on the features of circadian rhythm, the possible cause of the early morning seizures, the common subjective and objective sleep disorders, the alterations in sleep architecture, and the effect of sleep deprivation and sodium valproate (VPA). The aims of this study were to summarize the interaction between JME and sleep, to reveal JME sleep characteristics, to encourage clinicians to focus on JME and sleep, to heighten the positive diagnosis rate, to guide the treatment, to improve the prognosis, and to enhance the daily life quality of patients with JME. At the same time, this study aimed to present existing controversies, in order to necessitate further studies.

Status epilepticus in patients with juvenile myoclonic epilepsy: Frequency, precipitating factors and outcome

Status epilepticus (SE) is rarely described in patients with juvenile myoclonic epilepsy (JME), and little is known about its frequency, subtypes, and predictors and the prognosis of these patients. In this retrospective study, we aimed to analyze the incidence of SE in patients with JME and emphasize the risk factors and long-term outcome of SE in an epilepsy outpatient-based cohort. We included patients with JME with a history of predominant myoclonic seizures and at least one diagnostic EEG with normal background activity and bursts of typical ≥3-Hz generalized spike-polyspike and waves. We investigated the electroclinical features of patients with JME who had experienced SE and compared them with patients with JME without SE. Of the 133 patients with JME, only 5 patients were diagnosed with SE (3.8%) according to new criteria. The most common SE subtype was myoclonic SE (MSE, 4 patients), followed by generalized clonic-tonic-clonic SE (1 patient) and nonconvulsive SE (1 patient). One patient had both MSE and generalized clonic-tonic-clonic SE. In three out of five patients, recurrent episodes of SE were observed. Same seizure precipitants including sleep deprivation, inappropriate antiepileptic drug treatment, and noncompliance were identified in patients with JME with and without SE, not reaching a significant difference between the groups. Myoclonia limited to specific body parts (one arm, face, or head) were significantly more common in patients with JME with SE (p: 0.002). We did not find any significant correlation with drug-resistant course and SE. Status epilepticus is rarely observed in patients with JME, and MSE appears to be the most common subtype. Local myoclonia might predict SE in a subgroup of patients with JME. We may suggest that some patients with JME have a liability to SE, in addition to usual seizure precipitating factors of JME. It seems that SE per se does not affect the outcome of JME and the patients with SE did not have drug-resistant course in the final analysis.

Predictive value of EFHC1 variants for the long-term seizure outcome in juvenile myoclonic epilepsy

OBJECTIVE

This study aimed to determine the contribution of EFHC1 variants to the phenotypic variability of juvenile myoclonic epilepsy (JME) and to evaluate their diagnostic value regarding previously identified clinical long-term seizure outcome predictors in a consecutive cohort of patients with JME.

METHODS

Thirty-eight probands and three family members affected with JME were studied at a tertiary epilepsy center with a review of their medical records and a subsequent face-to-face interview. All coding EFHC1 exons and adjacent exon/intron boundaries were directly sequenced.

RESULTS

The previously reported EFHC1 mutation F229L was found in two cases who presented with early generalized tonic-clonic seizure (GTCS) onset and appeared to be associated with milder subtypes of JME. Variant R294H was identified in two further probands who had a subtype of JME developing from childhood absence epilepsy. However, segregation of the phenotype with this variant could not be confirmed in one family.

CONCLUSIONS

Our findings corroborate the heterogeneity of JME as an electroclinical epilepsy syndrome and provide evidence that genetic factors may influence and help predict the long-term seizure outcome in patients with JME.

Frontal and thalamic changes of GABA concentration indicate dysfunction of thalamofrontal networks in juvenile myoclonic epilepsy

OBJECTIVE

Juvenile myoclonic epilepsy (JME) has been considered to be a frontal variant of thalamocortical network dysfunction in epilepsy. Changes of γ-aminobutyric acid (GABA)ergic neurotransmission may play a key role in this dysfunction. Magnetic resonance spectroscopy (MRS) is the only noninvasive method to measure GABA concentrations in different brain regions. We measured GABA and other metabolite concentrations in the thalamus and frontal lobe of patients with JME.

METHODS

A specific protocol was used for determining GABA concentrations in the thalamus, frontal lobe, and motor cortex contralateral to the handedness in 15 patients with JME and 15 age-matched controls. In addition, we measured concentrations of glutamate and glutamine, N-acetyl-aspartate (NAA), myoinositol, creatine, and choline using MRS with short echo time. JME-related concentration changes were analyzed comparing patients to controls, also considering potential effects of antiepileptic drugs.

RESULTS

In patients with JME, GABA and NAA were reduced in the thalamus (p = 0.03 and p = 0.02), whereas frontal GABA and glutamine were elevated (p = 0.046 and p = 0.03). MRS revealed reduced NAA in the thalamic gray matter contralateral to the handedness (p = 0.04 each). These changes were found consistently in patients treated with new antiepileptic drugs and with valproate, although the extent of metabolic changes differed between these treatments.

SIGNIFICANCE

Decreased thalamic and increased frontal GABA suggest a dysfunction of GABAergic neurotransmission in these brain regions of patients with JME. The NAA decrease in the gray matter of the thalamus may hint to a damage of GABAergic neurons, whereas frontal increase of GABA and its precursor glutamine may reflect increased density in GABAergic neurons due to subtle cortical disorganization in the thalamofrontal network.

The treatment of juvenile myoclonic epilepsy

Juvenile myoclonic epilepsy is a common type of epilepsy with onset occurring during adolescence. This review provides a collection of evidence relating to the treatment of this type of epilepsy. Historically, the large majority of patients become seizure-free when treated with valproate. Over recent years, there has been a marked improvement in the pharmacological armamentarium by the physicians. Currently, administration of new antiepileptic drugs, such as levetiracetam, lamotrigine and topiramate, seems to have beneficial effects in the patients with poor response to valproate.

Clinical aspects of juvenile myoclonic epilepsy

Juvenile myoclonic epilepsy (JME) is a recognizable, frequent epileptic syndrome. The most typical ictal phenomenon is bilateral myoclonia without loss of consciousness (M), with most patients also presenting with generalized tonic-clonic seizures (GTCSs) and some with absence seizures (ASs). The most striking features of JME are its onset around the time of puberty and the fact that seizure episodes occur after awakening from a sleep period or in the evening relaxation period and are facilitated by sleep deprivation and sudden arousal. Photic sensitivity is common in the EEG laboratory but uncommon or unrecognized in daily life. The clinical features of JME make it easy to diagnose. In recent years, awareness of JME has increased, and patients are often accurately diagnosed clinically before confirmation by EEG. The typical circumstance at diagnosis is a first GTCS episode, and one learns during the interview that the patient has had M in the morning for some time before the GTCS episode. There are only few differential diagnoses: the adolescent-onset progressive myoclonus epilepsies, or other forms of idiopathic generalized epilepsies of adolescence. With JME being so common, we propose that a first GTCS episode in a teenager should be considered as revealing JME until proven otherwise.

Chronodependency and provocative factors in juvenile myoclonic epilepsy

In juvenile myoclonic epilepsy (JME), occurrence of seizures and epileptiform EEG discharges is influenced by internal and external factors. The most important internal factor is the chronodependency: the occurrence of myoclonic jerks in the early morning is one of the hallmarks of JME. Approximately two-thirds of the patients with JME report that seizures are provoked by a variety of general factors like stress, fatigue, fever, and sleep and more specific precipitants like flashing sunlight, music, reading, thinking, and excess alcohol. The prevalence rate of photosensitivity (photoparoxysmal EEG response) in patients with JME ranges from 8 to 90%; it is seen more often in females and adolescents and depends on drug use. Since both JME and photosensitivity are connected with generalized types of epilepsy and myoclonus, the two traits are comorbid for that reason. Epileptiform EEG discharges can be provoked by other activation methods: sleep, hyperventilation, and specific cognitive tasks. Attention seems to have a non-specific, inhibitory effect of the epileptiform discharges. Hyperventilation can induce absence seizures in patients with JME, while cognitive tasks are efficient in precipitating myoclonic seizures. This article is part of a supplemental special issue entitled Juvenile Myoclonic Epilepsy: What is it Really?

[Juvenile myoclonic epilepsy]

BACKGROUND

Juvenile myoclonic epilepsy (JME) is a generalised epilepsy with seizure onset in youth. The aim of this review is to present updated knowledge about the etiology, diagnosis and treatment of JME.

MATERIAL AND METHOD

The review is based on a judicious selection of original English language articles, meta-analyses, and reviews found in PubMed, and the authors' own experience with the patient group.

RESULTS

Seizure onset occurs in adolescence. All have myoclonias, about 90 % have generalized tonic-clonic seizures, and one third have absences. Myoclonic jerks are frequently the debut symptom, while tonic-clonic seizures appear later on. Patients are particularly susceptible to seizures shortly after waking. It is important to ask specifically about myoclonias as most patients do not report jerks spontaneously. The electroencephalograms of 44-81 % of the patients show discharges of 4-6 Hz polyspike waves. Focal EEG abnormalities may be seen in about 30 %. When patients are treated with valproate and seizure-precipitating factors are avoided, especially sleep deprivation, about 80 % become seizure-free. Lamotrigine and levetiracetam are alternative therapies for women of childbearing age. Attempts to taper off the medication after several years of seizure freedom entail a high risk of seizure relapse.

INTERPRETATION

As there may be features of focal epilepsy in the seizure semiology and/or the EEGs, it may be difficult to diagnose JME. Thus, many patients are misdiagnosed as having a focal epilepsy and are given antiepileptic drugs that may aggravate the tendency to seizures.

Pre- and post-dormitum epilepsies: idiopathic generalized epilepsies

Epilepsy and sleep have a profound bidirectional influence. Idiopathic generalized epilepsy (IGE) comprises a fascinating group of syndromes that constitute nearly one-third of all epilepsies. These syndromes are genetically determined and affect otherwise normal people of both sexes and all races. IGE manifests with typical absences, myoclonic jerks, and generalized tonic-clonic seizures, alone or in varying combinations and severity. IGE syndromes are typically modulated by the sleep-wake cycle, and particularly by the sleep-wake transition process, both in terms of the occurrence of seizures and interictal epileptiform discharges (IED), with pronounced susceptibility to sleep deprivation. IGE analysis from the point of view of arousal modulation enhances the concept of a biological continuum existing among IGE syndromes. At the same time, this analysis broaches the problem of syndromic diagnosis and identification of the factors influencing the phenotypic expression of some epileptic phenomena over the course of life with potential bidirectional influences between epileptic manifestations and sleep-wake processes.

Antiepileptic drugs withdrawal in patients with idiopathic generalized epilepsy

OBJECTIVES

To estimate the risk of seizure recurrence after antiepileptic drugs (AED) withdrawal and to identify related predictive features in patients with idiopathic generalized epilepsy (IGE) commencing at developing age (up to 16 year).

METHODS

Medical records of consecutive patients with IGE from two refferal hospitals were evaluated between 2001 and 2009. Inclusion criteria were clinical and EEG diagnosis of IGE and follow up for at least 2years after the AED withdrawal. The cohort consisted of 59 patients (38 females, 21 males). Follow up after withdrawal lasted 2-10years (median 3) Time to seizure relapse and predictive factors were analyzed by survival methods.

RESULTS

There were 21 (35.6%) patients with childhood absence epilepsy (CAE), 11 (18.6%) with juvenile absence epilepsy (JAE), 10 (16.9%) with isolated primary GTC seizures, and 17 (28.8%) with juvenile myoclonic epilepsy (JME). The relapses occured in 23 (52.2%) patients: one (6.2%) with CAE, 4 (50%) with JAE, 8 (80%) with IGE with GTC seizures and all with JME. During the first 6 months 54.5% patients relapsed (20% during withdrawal), 63.6% within 12 months, 81.8% within18 months and 95.4% within 24 months after withdrawal. Female gender, age at onset of seizures, seizure types, EEG worsening during/after AED withdrawal and age at withdrawal were significantly associated with relapse risk according to univariate analysis. In multivariate analysis, retained significant factors were: seizure types and EEG worsening.

CONCLUSION

Diagnosis of the specific IGE syndrome strongly affects relapse rate: the lowest was in CAE, the highest in JME. Independent risk factors for seizure relapse were: seizure type and EEG worsening during and/or after withdrawal.

Headache in juvenile myoclonic epilepsy

The objective of this study was to assess the prevalence of and risk factors for primary headaches in juvenile myoclonic epilepsy (JME). Headache was classified in 75 patients with JME using a questionnaire, and its prevalence was correlated with the literature on the general population and clinical data. Headache was present in 47 patients. Thirty-one had migraine [20 migraine without aura (MO), 11 migraine with aura (MA)]. Fourteen patients with migraine had tension-type headache (TTH) in addition. Sixteen had only TTH. Comparison with the general population revealed a significantly higher prevalence of migraine (RR 4.4), MO (3.6), MA (7.3) and TTH (3.4) in JME. Risk factors for migraine and MO were female gender and for MA family history of migraine in first-degree relatives. Migraine and MA were associated with fairly controlled generalized tonic clonic seizures, MO with absences. Together with its strong genetic background, JME appears to be an attractive homogenous subtype of epilepsy for genetic research on migraine.

Juvenile myoclonic epilepsy: epidemiology, pathophysiology, and management

Juvenile myoclonic epilepsy (JME) is a common epilepsy syndrome that begins most frequently in the early teenage years. It is officially classified as a type of idiopathic generalized epilepsy and is often under-recognized or misdiagnosed. This syndrome has a strong genetic component with multiple gene mutations being associated with the clinical presentation. Based upon genetic associations, there may be multiple pathophysiologic mechanisms for the disorder; the pathophysiology has not been clearly defined. A diagnosis of JME is made using the clinical history and EEG findings. Valproic acid is the primary antiepileptic drug (AED) used for JME, but some newer AEDs may be effective alternatives. Selection of an appropriate AED is essential to the proper management of JME, because of the possibility of exacerbation of seizures by some AEDs and the adverse effect profiles of effective drugs. It is important for clinicians to understand JME to correctly diagnose and manage patients with this syndrome.

Juvenile myoclonic epilepsy subsyndromes: family studies and long-term follow-up

The 2001 classification subcommittee of the International League Against Epilepsy (ILAE) proposed to 'group JME, juvenile absence epilepsy, and epilepsy with tonic clonic seizures only under the sole heading of idiopathic generalized epilepsies (IGE) with variable phenotype'. The implication is that juvenile myoclonic epilepsy (JME) does not exist as the sole phenotype of family members and that it should no longer be classified by itself or considered a distinct disease entity. Although recognized as a common form of epilepsy and presumed to be a lifelong trait, a long-term follow-up of JME has not been performed. To address these two issues, we studied 257 prospectively ascertained JME patients and encountered four groups: (i) classic JME (72%), (ii) CAE (childhood absence epilepsy) evolving to JME (18%), (iii) JME with adolescent absence (7%), and (iv) JME with astatic seizures (3%). We examined clinical and EEG phenotypes of family members and assessed clinical course over a mean of 11 +/- 6 years and as long as 52 years. Forty per cent of JME families had JME as their sole clinical phenotype. Amongst relatives of classic JME families, JME was most common (40%) followed by grand mal (GM) only (35%). In contrast, 66% of families with CAE evolving to JME expressed the various phenotypes of IGE in family members. Absence seizures were more common in family members of CAE evolving to JME than in those of classic JME families (P < 0.001). Female preponderance, maternal transmission and poor response to treatment further characterized CAE evolving to JME. Only 7% of those with CAE evolving to JME were seizure-free compared with 58% of those with classic JME (P < 0.001), 56% with JME plus adolescent pyknoleptic absence and 62% with JME plus astatic seizures. Long-term follow-up (1-40 years for classic JME; 5-52 years for CAE evolving to JME, 5-26 years for JME with adolescent absence and 3-18 years for JME with astatic seizures) indicates that all subsyndromes are chronic and perhaps lifelong. Seven chromosome loci, three epilepsy-causing mutations and two genes with single nucleotide polymorphisms (SNPs) associating with JME reported in literature provide further evidence for JME as a distinct group of diseases.

[EEG recording after sleep deprivation in a series of patients with juvenile myoclonic epilepsy]

Seizures in Juvenile Myoclonic Epilepsy (JME) are dependent on the sleep-wake cycle and precipitant factors, among which sleep deprivation (SD) is one of the most important. Still an under diagnosed syndrome, misinterpretation of the EEGs contributes to diagnostic delay. Despite this, a quantitative EEG investigation of SD effects has not been performed. We investigated the effect of SD on EEGs in 41 patients, aged 16-50 yr. (mean 25.4), who had not yet had syndromic diagnosis after a mean delay of 8.2 yr. Two EEG recordings separated by a 48-hour interval were taken at 7 a.m. preceded by a period of 6 hours of sleep (routine EEG) and after SD (sleep-deprived EEG). The same protocol was followed and included a rest wakefulness recording, photic stimulation, hyperventilation and a post-hyperventilation period. The EEGs were analyzed as to the effect of SD on the number, duration, morphology, localization and predominance of abnormalities in the different stages. A discharge index (DI) was calculated. Out of the 41 patients, 4 presented both normal EEG recordings. In 37 (90.2%) there were epileptiform discharges (ED). The number of patients with ED ascended from 26 (70.3%) in the routine EEG to 32 (86.5%) in the sleep-deprived exam. The presence of generalized spike-wave and multispike-wave increased from 20 (54.1%) and 13 (35.1%) in the first EEG to 29 (78.4%) and 19 (51.4%) in the second, respectively (p<0.05 and p<0.01). As to localization, the number of generalized, bilateral and synchronous ED increased from 21 (56.8%) to 30 (81.1%) (p<0.01). The DI also increased; while 8 patients (21.6%) presented greater rate in the routine EEG, 25 (67.6%) did so in the sleep-deprived EEG mainly during somnolence and sleep (p<0.01). Moreover, the paroxysms were also longer in the sleep-deprived EEG. Sleep-deprived EEG is a powerful tool in JME and can contribute significantly to the syndromic characterization of this syndrome.

Self-perception of factors that precipitate or inhibit seizures in juvenile myoclonic epilepsy

PURPOSE

To assess self-perception of factors that precipitate or inhibit seizures in patients with juvenile myoclonic epilepsy (JME).

PATIENTS AND METHODS

Thirty-six males and 39 females with JME and mean age of 25.8+/-8.7 years were analysed. All patients completed a standardized questionnaire to assess for the presence or absence of precipitant or inhibitory factors for their seizures in a face-to-face interview. These data were statistically analysed through logistic and linear regression models and Phi coefficient.

RESULTS

Ninety-two percent of the patients identified at least one precipitating factor (PF). In order of frequency the following PFs were recorded: stress (83%), sleep deprivation (77%), specific thoughts/mental concentration (23%), performance of hand activities and complex finger movements (20%), flashing lights and playing games (15%), speaking out in public (11%) and alcohol intake (11%), reading (7%), calculating and writing (5%), playing musical instruments (4%), drawing (3%), and specific types of music (1%). Menstrual cycle was the third most important PF in the women (33%). Although PFs were easily recognized, 77% of the patients stated that they were unable to avoid the occurrence of the seizures.

CONCLUSIONS

Structured questionnaire is useful in stimulating patients to self-report seizure precipitants. Patients with higher education and uncontrolled seizures identified them more easily. The presence of a significant number of uncommon PFs, such as mental and motor hand tasks, considered uncommon for other epileptic syndromes, suggests that the role of these factors may be under-recognized in JME.

Cognitive function in juvenile myoclonic epilepsy

In this study, we examined 35 patients with juvenile myoclonic epilepsy (JME) and 35 healthy volunteers. We used tests of cognitive performance (mini mental state examination, verbal and visual memory, visuospatial, frontal function, attention). In the JME group, we examined age, sex, family history, education level, age of seizure onset, seizure types, characteristics of EEG, duration of the therapy, drug dose and level, and verbal IQ level. Additionally, patients initially diagnosed as JME and patients who were initially under inappropriate drug therapy because of misdiagnosis were compared. As a result, we found statistically significant differences between JME patients and the control group with respect to verbal and visual memory. Furthermore, JME patients had impaired frontal and visuospatial function compared with the control group. We detected negative effects of younger age, family history, and absence seizures on cognitive function in JME patients.

Clinical expression and EEG features of patients with juvenile myoclonic epilepsy (JME) from North India

We aimed to characterize the clinical profile, EEG features and response to treatment of juvenile myoclonic epilepsy (JME) patients. We studied 103 JME probands with a standard protocol recording age of onset, type, frequency of seizures, EEG data, detailed family history and response to treatment in a superspeciality university hospital in New Delhi. The mean age of onset of disease was 14.01 +/- 3.14 years with a male to female ratio of 1.19 : 1. The myoclonic jerks were present in all the probands, generalized tonic-clonic seizures (GTCS) were present in 75.72% and 11.65% probands had absence seizures. The incidence of febrile convulsion (FC) was higher (9.7%) in our JME probands reflecting some ethnic variation or ascertainment bias. There was a considerable delay (of approximately 5.26 +/- 4.61 years) in the diagnosis of JME in our probands because most of the patients were referred from private physicians who were possibly not familiar with this epileptic syndrome in this part of the world or thought it was a milder variety of GTCS. The family history was positive in 25.24% JME probands among first- and second-degree relatives. An interictal EEG was found to be abnormal in 81 (78.64%) patients with the predominant abnormality being generalized polyspike and wave (PSW) discharges (39.80% probands). The majority of patients (80.58%) showed a good response to treatment with valproate alone. There was a subset of patients (11.65%) who required the addition of other antiepileptic drugs (AEDs) for control of GTCS: 7.76% of JME patients were diagnosed as cases of GTCS by private practitioners before they were registered in our study and their seizures were well controlled on other AEDs (without valproate) prescribed by the referring physicians (carbamazepine-4, phenytoin-2, clobazam-2). It is concluded that the clinical features and EEG data of JME probands were comparable to reports from other parts of the world except for the fact that the incidence of FC was higher in our JME patients. There was a delay in the diagnosis of JME due to unfamiliarity with the epileptic syndrome among private practitioners in this part of the world. There was a subset of JME patients who had complete seizure control on other AEDs besides valproate.

Neuropsychological EEG activation in patients with epilepsy

To examine the effects of higher mental activity on the EEG, 480 Japanese patients with different types of epilepsy were subjected to potentially provocative cognitive tasking, termed 'neuropsychological EEG activation' (NPA), during standard EEG recordings. NPA tasks consisted of reading, speaking, writing, written arithmetic calculation, mental arithmetic calculation and spatial construction. The NPA tasks provoked epileptic discharges in 38 patients (7.9%) and were accompanied by myoclonic seizures in 15 patients, absence seizures in eight and simple partial seizures in one. Among the cognitive tasks, mental activities mainly associated with use of the hands, i.e. writing (68.4%), written calculation (55. 3%) and spatial conction (63.2%), provoked the most discharges, followed by mental calculation (7.9%) and reading (5.3%). Detailed examination of the precipitating events revealed action-programming type activities to be the most crucial in 32 out of the 38 patients (84.2%), followed by thinking type activities in four patients (10. 5%). Regarding the classification of epilepsies proposed by the International League Against Epilepsy, seizure-precipitating mental activities in our series were almost exclusively (in 36 out of the 38 patients) related to idiopathic generalized epilepsies (IGEs) including juvenile myoclonic epilepsy, juvenile absence epilepsy, grand mal epilepsy on awakening and childhood absence epilepsy, and were rarely (in only two out of the 38 patients) related to temporal lobe epilepsy. In our IGE patients, the provocative effects of NPA were related to myoclonic seizures rather than absence or generalized tonic-clonic seizures. These results suggest that NPA is a useful tool for examining the relationship between cognitive function and epileptic seizures, and that the IGE patients with myoclonic seizures are vulnerable to higher mental activities requiring action-programming or thinking.

Febrile seizures: genetics and relationship to other epilepsy syndromes

The relationship between febrile seizures and epilepsy has long been debated. We argue that there is some specificity to the types of epilepsy that follow febrile seizures, rather than febrile seizures being a nonspecific marker of a lowered seizure threshold. The relationship between febrile seizures and later epilepsy is frequently genetic. Recent clinical and molecular genetic studies suggest that there are a number of syndrome-specific genes for febrile seizures.

Juvenile myoclonic epilepsy: clinical and EEG features

We aimed to characterize the clinical profile and EEG features of 43 patients with juvenile myoclonic epilepsy. In a retrospective design we studied the records of, and re-interviewed, 43 patients diagnosed with JME from the epilepsy clinic data base. Furthermore, available EEGs were re-evaluated. Of the patients 72% were female and 28% male. Average age of onset was 13 (5.5-22) years for absences, 16 (5.2-25) years for myoclonic seizures, and 16 (8-29) years for generalized tonic-clonic seizures. Forty-two percent reported asymmetric or unilateral myoclonic jerks. Commonly reported precipitating factors were sleep deprivation (84%), stress (70%), and alcohol consumption (51%). EEG findings included rapid spike-wave and polyspike-wave.

Clinical observations of juvenile myoclonic epilepsy in 131 patients: a study in South India

We studied clinical features of 131 patients with juvenile myoclonic epilepsy (JME). The prevalence was 7.7% among the epileptic patients registered. The mean age at onset was 13.37+/-4.93 years and the diagnosis was established at a mean age of 19.53+/-7.85 years. Absence seizures were reported by 27 (20.6%) patients, myoclonic jerks by 131 (100%) and generalized tonic-clonic seizures (GTCS) by 111 (84.7%). The triad of absence seizures, myoclonic jerks and GTCS was noted in 23 (17.5%) patients, 88 (67.2%) had myoclonic jerks and GTCS, 4 (3%) had absence seizures and myoclonic jerks and 16 (12.2%) had only myoclonic jerks. Early onset absences were seen in 21 (16%) patients and the onset was late in 6 (4.6%). Absences antedated other types of seizures in all the patients. Myoclonic jerks were predominantly unilateral or had unilateral onset in 22 (16.8%). In 17 (13%) patients GTCS antedated myoclonic jerks. Myoclonic jerks had characteristic circadian distribution in 112 (85.5%) patients. On awakening GTCS occurred in 87 (78.4%) patients and in 4 (3.6%) patients they were purely nocturnal. Sleep deprivation was the most important precipitating factor (54.2%). Initial electroencephalogram (EEG) showed classical generalized spike or multiple-spike slow-wave paroxysms in 81% of records. Focal EEG abnormalities were noted in 20.6% of records. The most common focal abnormality was voltage asymmetry. A family history of epilepsy was noted in 31 (23.6%) probands. Diagnosis of JME was made in all the cases in the clinic. The factors responsible for delay in diagnosis of the 36 patients seen by neurologists included failure to ask or interpret the history which was otherwise suggestive of myoclonic jerks in all 36 (100%) cases, the type of seizure for which the patients sought medical attention, and misinterpretation of EEGs in 28 patients. Diagnosis of partial epilepsy was made in seven patients. The factors responsible for such diagnoses were, unilateral jerks in one patient, unilateral jerks and absence seizures in three patients and focal EEG abnormalities in three patients.

Interictal mood and personality disorders in temporal lobe epilepsy and juvenile myoclonic epilepsy

BACKGROUND

Mood disorders have been described as the commonest psychiatric disorders in patients with temporal lobe epilepsy. Secondary depression in temporal lobe epilepsy could be interpreted either as an adjustment reaction to a chronic disease or as a limbic dysfunction. To clarify this issue, a controlled study of psychiatric disorders was conducted in different forms of epileptic and non-epileptic chronic conditions.

METHODS

Twenty outpatients with temporal lobe epilepsy, 18 outpatients with juvenile myoclonic epilepsy--a primary generalised seizure disorder--20 matched type I diabetic patients, and 20 matched normal controls were assessed by a structured interview (SADS) and by self rating scales (Beck depression inventory (BDI) and the state and trait anxiety scales STAIX1 and STAIX2).

RESULTS

Sixteen (80%) patients with temporal lobe epilepsy fulfilled the criteria for a psychiatric diagnosis at the SADS interview with a significantly higher frequency than patients with juvenile myoclonic epilepsy (22%) and diabetic patients (10%) (P < 0.0001). The most frequent disorder in temporal lobe epilepsy was a mood disorder: 11 (55%) patients with temporal lobe epilepsy had depression compared with three patients with juvenile myoclonic epilepsy and two diabetic patients (P < 0.001). Eight patients with temporal lobe epilepsy with an affective disorder also had a comorbid personality or anxiety disorder. Patients with temporal lobe epilepsy scored significantly higher on BDI, STAIX1, and STAIX2 than the three control groups (P < 0.001, P < 0.01, P < 0.001).

CONCLUSIONS

Patients with temporal lobe epilepsy have a higher incidence of affective and personality disorders, often in comorbidity, than patients with juvenile myoclonic epilepsy and diabetic patients suggesting that these psychiatric disorders are not an adjustment reaction to a chronic disease but rather reflect a limbic dysfunction.

Juvenile myoclonic epilepsy in chromosome 6p12-p11: locus heterogeneity and recombinations

We recently analyzed under homogeneity a large pedigree from Belize with classic juvenile myoclonic epilepsy (JME). After a genome wide search with 146 microsatellites, we obtained significant linkage between chromosome 6p markers, D6S257 and D6S272, and both convulsive and EEG traits of JME. Recombinations in two affected members defined a 40 cM JME region flanked by D6S313 and D6S258. In the present communication, we explored if the same chromosome 6p11 microsatellites also have a role in JME mixed with pyknoleptic absences. We allowed for heterogeneity during linkage analyses. We tested for heterogeneity by the admixture test and looked for more recombinations. D6S272, D6S466, D6S294, and D6S257 were significantly linked (Zmax > 3.5) to the clinical and EEG traits of 22 families, assuming autosomal dominant inheritance with 70% penetrance. Pairwise Zmax were 4.230 for D6S294 (theta m = f at 0.133) and 4.442 for D6S466 (theta m = f at 0.111). Admixture test (H2 vs. H1) was significant (P = 0.0234 for D6S294 and 0.0128 for D6S272) supporting the hypotheses of linkage with heterogeneity. Estimated proportion of linked families, alpha, was 0.50 (95% confidence interval 0.05-0.99) for D6S294 and D6S272. Multipoint analyses and recombinations in three new families narrowed the JME locus to a 7 cM interval flanked by D6S272 and D6S257.