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Shlomo Shinnar

Publications and source records attributed to Shlomo Shinnar.

36 records · Page 2Linked to original sources

Malic enzyme 2 may underlie susceptibility to adolescent-onset idiopathic generalized epilepsy.

Idiopathic generalized epilepsy (IGE) is a class of genetically determined, phenotypically related epilepsy syndromes. Linkage analysis identified a chromosome 18 locus predisposing to a number of adolescent-onset IGEs. We report a single-nucleotide polymorphism (SNP) association analysis of the region around the marker locus with the high LOD score. This analysis, which used both case-control and family-based association methods, yielded strong evidence that malic enzyme 2 (ME2) is the gene predisposing to IGE. We also observed association among subgroups of IGE syndromes. An ME2-centered nine-SNP haplotype, when present homozygously, increases the risk for IGE (odds ratio 6.1; 95% confidence interval 2.9-12.7) compared with any other genotype. Both the linkage analysis and the association analysis support recessive inheritance for the locus, which is compatible with the fact that ME2 is an enzyme. ME2 is a genome-coded mitochondrial enzyme that converts malate to pyruvate and is involved in neuronal synthesis of the neurotransmitter gamma-aminobutyric acid (GABA). The results suggest that GABA synthesis disruption predisposes to common IGE and that clinical seizures are triggered when mutations at other genes, or perhaps other insults, are present.

Adolescent↗

Mortality in childhood-onset epilepsy.

OBJECTIVES: To evaluate mortality in children with newly diagnosed epilepsy, to determine the risk of death, and to identify predictors of death from the point of diagnosis. DESIGN: Prospective community-based cohort of 613 children with newly diagnosed epilepsy. The outcome measure was death. Chi2 Tests were used for bivariate analyses and the Cox proportional hazards model for multivariable analyses. Standardized mortality ratios were used to quantify the excess mortality in the cohort relative to the population. RESULTS: Thirteen deaths occurred during 4733 person-years of follow-up, for a crude death rate of 2.7 per 1000 person-years (0.52 per 1000 person-years in those with nonsymptomatic epilepsy and 12.6 per 1000 person-years in those with symptomatic epilepsy). Ten deaths were associated with the underlying cause of the seizures, 2 were associated with the occurrence or probable occurrence of seizures, and 1 was unrelated to seizures or the underlying disorder. On multivariable analysis, symptomatic etiology (rate ratio, 10.2; 95% confidence interval [CI], 2.1-49.6) and epileptic encephalopathy (rate ratio, 13.3; 95% CI, 3.4-51.7) were independently associated with mortality. The overall standardized mortality ratio for the cohort was 7.54 (95% CI, 4.38-12.99). In children with symptomatic epilepsy, the standardized mortality ratio was 33.46 (95% CI, 18.53-60.43), and in those with nonsymptomatic epilepsy, it was 1.43 (95% CI, 0.36-5.73). CONCLUSIONS: Children with epilepsy have an increased risk of death. Most deaths occur in children with severe underlying conditions and are not directly related to the occurrence of seizures.

Adolescent↗

Landau-Kleffner syndrome, electrical status epilepticus in slow wave sleep, and language regression in children.

The Landau-Kleffner syndrome (LKS) and electrical status epilepticus in slow wave sleep (ESES) are rare childhood-onset epileptic encephalopathies in which loss of language skills occurs in the context of an epileptiform EEG activated in sleep. Although in LKS the loss of function is limited to language, in ESES there is a wider spectrum of cognitive impairment. The two syndromes are distinct but have some overlap. The relationship between the epileptiform EEG abnormalities and the loss of cognitive function remains controversial, even in LKS which is the most widely accepted as an acquired epileptic aphasia. Language regression also occurs in younger children, frequently in the context of a more global autistic regression. Many of these children have epileptiform EEGs. The term autistic regression with epileptiform EEG has been proposed for these children. Whether these children are part of an extended LKS spectrum is very controversial, because there are differences in age of onset, clinical phenotype, and EEG findings. An understanding of the available data on clinical characteristics, EEG findings, pathology, prognosis, and treatment of these syndromes is essential for further progress in this area.

Brain↗

Modeling remission and relapse in pediatric epilepsy: application of a Markov process.

Seizure outcome is frequently described in terms of patients ever attaining remission or being in terminal remission. Outcomes are more complicated and, over many years, repeated remission and relapses may occur. These are difficult to quantify with standard survival techniques used in analysis of remission and relapse. The Markov process, which allows one to track a patient's state (remission or not) over time, provides a suitable approach for studying repeated remission and relapse. In a prospective community-based study of children followed from the point of the initial diagnosis of epilepsy, we examined the probability of repeated remission and relapse over up to three different remission episodes (minimum 1 year each) per patient. The role of epilepsy syndrome was the main determinant of remission-relapse patterns considered in the analysis. Two different Markov models were used, one involving three states and the other seven states. Of 613 children initially recruited into the study, 602 were followed at least 1 year and thus eligible for the analysis. Almost 90% of the cohort experienced a remission; however, almost half then relapsed. Second remissions occurred in 81% of those who relapsed of whom 38% relapsed again. A third remission occurred in 82% of those after a second relapse of whom 58% relapsed yet again. After the first 2 years, approximately 70% of the cohort was in remission, 20% was no longer in remission having relapsed, and 10% had never been in remission. Significant differences were seen by underlying epilepsy syndrome. Children with one of the epileptic encephalopathies were least likely of all syndrome groups ever to remit. Those with symptomatic partial epilepsies were less likely to remit than children with any of the other syndromes, idiopathic partial or generalized, cryptogenic partial, and unclassified. Differences between these last groups became apparent when considering their subsequent remission and relapse histories. These differences were best seen in the seven-state model. For example, idiopathic partial epilepsies were most likely to enter remission and never relapse. By contrast, idiopathic generalized and cryptogenic partial epilepsies were more likely to remit and relapse repeatedly. The Markov approach provides an alternative to standard survival techniques for understanding remission and relapse outcomes in epilepsy. Its advantage is that it allows one to track the individuals' outcome over time even as the condition fluctuates. The technique would also be applicable in virtually any remitting-relapsing disorder.

Adolescent↗

Long-term cognitive outcomes of a cohort of children with cryptogenic infantile spasms treated with high-dose adrenocorticotropic hormone.

PURPOSE: To evaluate the outcome of children with cryptogenic infantile spasms treated with high-dose synthetic adrenocorticotropic hormone (ACTH) and the relation between early treatment, within 1 month of onset, and outcome. METHODS: We assessed the long-term cognitive and seizure outcomes of 37 patients with cryptogenic infantile spasms (onset, age 3 to 9 months) receiving standardized treatment regimen of high-dose tetracosactide depot, 1 mg IM every 48 h for 2 weeks, with a subsequent 8- to 10-week slow taper and followed by oral prednisone, 10 mg/day for a month, with a subsequent slow taper for 5 months or until the infant reached the age of 1 year, whichever came later. Development was assessed before treatment. Seizure outcomes were followed up prospectively. Cognitive outcomes were determined after 6 to 21 years and analyzed in relation to treatment lag and pretreatment regression. RESULTS: Twenty-two infants were treated within 1 month of onset of infantile spasms, and 15 after 1 to 6.5 months. Normal cognitive outcome was found in all 22 (100%) patients of the early-treatment group, and in 40% of the late-treatment group. Normal cognitive outcome was found in all 25 (100%) patients who had no or only mild mental deterioration at presentation, including four in the late-treatment group but in only three of the 12 patients who had had marked or severe deterioration before treatment. CONCLUSIONS: Early treatment of cryptogenic infantile spasms with a high-dose ACTH protocol is associated with favorable long-term cognitive outcomes. Once major developmental regression lasts for a month or more, the prognosis for normal cognitive outcome is poor. Further studies are needed on the optimal treatment regimen for this disorder.

Administration, Oral↗

Perceived impact of childhood-onset epilepsy on quality of life as an adult.

PURPOSE: Childhood-onset epilepsy is a common disorder. The long-term impact of having childhood epilepsy on quality of life (QOL) as an adult, whether or not seizures are in remission, has not been systematically studied. METHODS: A population-based cohort of 245 children younger than 16 years with active epilepsy between 1961 and 1964 residing in the catchment area of Turku University Hospital was followed up prospectively until 1997. Of the 99 surviving cases with uncomplicated epilepsy and 99 matched population controls, 91 subjects and controls completed questionnaires on QOL and psychosocial outcomes. RESULTS: Of the 91 subjects, 61 (67%) were in remission off medication, 13 (14%) in remission on medications, and 17 (19%) were not in remission. Subjects on medication, whether in remission or not, had worse scores on both general measures of QOL and epilepsy-specific measures than did either controls or subjects in remission off medications. They also had significantly higher rates of unemployment (p < 0.001) and lower socioeconomic status. These differences could not be accounted for by differences in education or seizure frequency. Subjects in remission off medication had rates of employment and socioeconomic status similar to those of controls. All subjects, regardless of remission status, had lower rates of marriage and of having children than did controls (p < 0.001). CONCLUSIONS: Childhood-onset epilepsy has a persistent long-term adverse impact on health-related quality of life. The major impact is on those still on medications as adults, whether or not they are in remission. The impact on those in remission off medications is relatively modest.

Adult↗

Development of syndrome severity scores for pediatric epilepsy.

PURPOSE: A severity rating for each of the pediatric epilepsy syndromes can contribute to a more comprehensive understanding of seizure condition severity. We describe the development of the Epilepsy Syndrome Severity Scores-Child (ESSS-C). METHODS: The Delphi Technique was used to establish severity scores for pediatric epileptic syndromes as defined by the International League Against Epilepsy (ILAE). Pediatric neurologists with expertise in epilepsy were asked to rate the severity of each syndrome on a scale of 1 to 10, considering: (a) response to medical treatment, (b) seizure severity, and (c) long-term prognosis. Syndrome severity ratings took place in four different rounds. Experts provided initial scores in rounds 1 and 2. RESULTS: Of the 18 experts who agreed to participate in the development of the scale, 12 completed all four rounds. The median served as the syndrome severity score if the mean and median agreed within 0.5. Otherwise, whichever of these two numbers was closest to the mode was selected. Syndromes that were rated with high severity scores (9 or 10) or low severity scores (1 or 2) had unanimous or near unanimous ratings. The syndromes with scores in the middle range (4 to 8) had a wider range of ratings. CONCLUSIONS: If further studies provide empirical support for the validity of these epileptic syndrome severity scores, then the ESSS-C has potential for use both clinically and in future research in the prediction of outcomes of treatments.

Age Factors↗

Longitudinal assessment of adaptive behavior in infants and young children with newly diagnosed epilepsy: influences of etiology, syndrome, and seizure control.

OBJECTIVES: The outcomes of childhood-onset epilepsy are highly varied and have several potential determinants. We examined the independent effects of syndrome type, seizure control, and etiology over time on adaptive behavior as measured by the Vineland Scales of Adaptive Behavior. METHODS: As part of a prospective community-based study of newly diagnosed epilepsy, parents of children who were younger than 3 years at the time of initial onset of epilepsy completed the Vineland Adaptive Behavior Scales screener version at entry into the study and once a year thereafter for up to 3 years. Longitudinal analyses were performed on the composite score as the primary outcome and on the 4 domain scores (communication, socialization, motor, and daily living) as confirmatory/secondary outcomes to determine the effects of syndrome (epileptic encephalopathy or other), seizure control (intractable or not), and etiology (symptomatic or not) on adaptive behavior at the time of initial diagnosis and over time. RESULTS: A total of 613 children were enrolled in the study, and 191 (31%) of these children met the age criterion for this analysis. Of these, 172 (90%) had adequate follow-up and had completed baseline and at least 1 subsequent Vineland assessment. Overall, Vineland scores (composite and individual domains) were somewhat below average at baseline (initial diagnosis). All declined significantly over time. All of the effects at baseline, however, were limited to children with epileptic encephalopathies and symptomatic etiology. Substantial declines over time occurred in these children, and there was an independent effect of intractable seizures as well. In children with none of these factors ( approximately 75% of the study group), baseline scores were consistent with average performance for the test norms and there was no evidence of any decline over time. CONCLUSIONS: Children with an underlying symptomatic etiology or a syndrome that can be characterized as 1 of the epileptic encephalopathies demonstrate impaired adaptive behavior at the time of initial diagnosis and experience additional declines in assessments of age-adjusted performance over time. Our results suggest that future seizure outcome is not strongly reflected in adaptive behavior at initial diagnosis but that it takes its toll on the child over time. Understanding how each of these factors affects development and how they interact with each other is the next step in designing effective interventions for lessening the impact of these disorders on the child. In the majority of children with onset of epilepsy during infancy or early childhood, adaptive behavior is within the normal range and does not show any evidence of declining over time. Although this is encouraging, it does not contradict other studies that have demonstrated behavioral and relatively subtle cognitive difficulties in school-aged children with epilepsy. Long-term follow-up in this cohort will permit us to examine the predictive value of the Vineland for later behavioral and cognitive difficulties in this group that, so far, seems to be doing well.

Activities of Daily Living↗

Stress and epilepsy: a patient perception survey.

A questionnaire was administered to patients in the Montefiore Medical Center outpatient epilepsy department to assess perceptions about stress, seizures, and stress reduction. Eighty-nine patients completed the questionnaire. Overall, 64% of patients reported the belief that stress increased the frequency of their seizures. This belief was not significantly associated with gender, age, location of care, epilepsy classification, or seizure control, but was significantly associated with a shorter duration of epilepsy (P=0.04). Thirty-two percent of subjects had tried stress reduction modalities for epilepsy. Of those who had not, 53% were willing to try, and this willingness was significantly associated with a greater number of seizures in the prior 2 months (P=0.006) and the belief that stress was associated with seizures (P=0.04). Both major and minor stressors were reported with equal frequency. The majority of our study population believe that stress and seizures are related, and are willing to try stress reduction techniques for seizure control. We believe that these findings indicate a need for a prospective study to evaluate the role of stress and stress reduction as an additional potential therapeutic modality for epilepsy.

Adolescent↗

Clinical characteristics of language regression in children.

The spectrum of language regression in childhood is incompletely understood. To describe the features of this disorder more fully, we reviewed the records of 196 consecutive children (143 males and 53 females) with language regression or perceived plateau evaluated between 1988 and 1994 by a child neurologist. Mean age at regression was 21.2 months and the mean interval to referral was 34.8 months. A trigger for the regression was identified in 74 of the children (38%) and was associated with a more rapid regression. Mean age at follow-up was 64 months (SD 55). Seventy per cent of the children became nonverbal, and 75% were cognitively impaired. Language regression was associated with a more global autistic regression in 93% of children. There was a history of seizures in 15% of the children. Some recovery occurred in 61% but only one child recovered fully. Improvement was more likely in the 49% who were entirely developmentally normal before the regression. We conclude that language regression in childhood is a serious disorder with significant long-term morbidity.

Autistic Disorder↗

The multicenter study of epilepsy surgery: recruitment and selection for surgery.

PURPOSE: Multiple studies have examined predictors of seizure outcomes after epilepsy surgery. Most are single-center series with limited sample size. Little information is available about the selection process for surgery and, in particular, the proportion of patients who ultimately have surgery and the characteristics that identify those who do versus those who do not. Such information is necessary for providing the epidemiologic and clinical context in which epilepsy surgery is currently performed in the United States and in other developed countries. METHODS: An observational cohort of 565 surgical candidates was prospectively recruited from June 1996 through January 2001 at six Northeastern and one Midwestern surgical centers. Standardized eligibility criteria and protocol for presurgical evaluations were used at all seven sites. RESULTS: Three hundred ninety-six (70%) study subjects had resective surgery. Clinical factors such as a well-localized magnetic resonance imaging (MRI) abnormality and consistently localized EEG findings were most strongly associated with having surgery. Of those who underwent intracranial monitoring (189, 34%), 85% went on to have surgery. Race/ethnicity and marital status were marginally associated with having surgery. Age, education, and employment status were not. Demographic factors had little influence over the surgical decision. More than half of the patients had intractable epilepsy for >/=10 years and five or more drugs had failed by the time they initiated their surgical evaluation. During the recruitment period, eight new antiepileptic drugs were approved by the Food and Drug Administration for use in the United States and came into increasing use in this study's surgical candidates. Despite the increased availability of new therapeutic options, the proportion that had surgery each year did not fluctuate significantly from year to year. This suggests that, in this group of patients, the new drugs did not provide a substantial therapeutic benefit. CONCLUSIONS: Up to 30% of patients who undergo presurgical evaluations for resective epilepsy surgery ultimately do not have this form of surgery. This is a group whose needs are not currently met by available therapies and procedures. Lack of clear localizing evidence appears to be the main reason for not having surgery. To the extent that these data can address the question, they suggest that repeated attempts to control intractable epilepsy with new drugs will not result in sustained seizure control, and eligible patients will proceed to surgery eventually. This is consistent with recent arguments to consider surgery earlier rather than later in the course of epilepsy. Postsurgical follow-up of this group will permit a detailed analysis of presurgical factors that predict the best and worst seizure outcomes.

Adolescent↗

Status epilepticus in a population-based cohort with childhood-onset epilepsy in Finland.

Little is known about the time course over which status epilepticus occurs in childhood-onset epilepsy and its impact on long-term prognosis. A population-based cohort of 150 children younger than age 16 years with new onset epilepsy between 1961 and 1964 residing in the catchment area of Turku University Hospital was observed prospectively until 1997. The occurrence of status epilepticus and recurrent status epilepticus, risk factors for status epilepticus, and the impact of status epilepticus on prognosis were examined. Of the 150 cases, 41 patients (27%) experienced an episode of status epilepticus of whom 22 patients (56%) had two or more episodes. The risk of status epilepticus was highest at the onset of the disorder with 30 (73%) cases occurring before (n = 12) or at (n = 18) onset and 37 (90%) cases within 2 years of onset. On multivariable analysis, risk factors for status epilepticus included remote symptomatic cause, age of onset 6 years or younger, and partial seizures. Specific epilepsy syndromes also were associated with a differential risk of status epilepticus. The occurrence of status epilepticus did not alter the mortality rates and had only a modest impact on the probability of attaining remission. In subjects with no other neurological handicap, social and educational outcomes were similar in those with status epilepticus and those with no history of status epilepticus. We conclude that status epilepticus is a common occurrence in childhood-onset epilepsy. When it does occur, it occurs early in the course of the disorder. The occurrence of status epilepticus does not appear to have significant adverse impact on long-term prognosis of childhood-onset epilepsy.

Adolescent↗

Do occasional brief seizures cause detectable clinical consequences?

Seizures, particularly when prolonged or frequent, have been associated with a variety of adverse outcomes. However, epidemiological data provide little evidence for adverse effects of isolated brief seizures per se. Even the animal data is mostly for prolonged or frequent seizures. Febrile seizures lasting < 10 min have not been associated with adverse seizures or cognitive outcomes. Treating either febrile seizures or other acute symptomatic seizures does not reduce the risk of subsequent epilepsy. In subjects with a first unprovoked seizure, seizure duration does not influence recurrence risk. Furthermore, treatment after a first unprovoked seizure reduces recurrence risk, but does not alter long-term prognosis. In epidemiological studies of newly diagnosed epilepsy, the number of seizures prior to therapy does not influence prognosis. There are a variety of specific epilepsy syndromes associated with poor cognitive outcomes and with progressive loss of function. However, the poor outcomes in these syndromes do not appear to be the result of seizures per se but rather to the specific syndrome and to the frequent interictal spike activity seen in these patients. Antiepileptic drugs, while effective in reducing seizure recurrence are also associated with a variety of potential adverse effects. On a risk-benefit basis, the available epidemiologic data do not justify starting treatment after the first seizure to attempt to influence long-term prognosis.

Animals↗

Macrocephaly in children with developmental disabilities.

In a community-based study of 4,309 children with neurodevelopmental disabilities who were referred to the Institute for Child Development, Tel Aviv, Israel, 62 (1.4%) had macrocephaly (head circumference above the ninety-eighth percentile for age), of whom 42 (1%) had macrocephaly not associated with hydrocephalus. With the exception of neonatal respiratory distress the incidence of perinatal complications was not different from that in other children referred to the Institute for Child Development. In children with developmental disabilities, macrocephaly was a significant risk factor for febrile seizures (odds ratio = 3.1, P < 0.001) and epilepsy (odds ratio = 7.7, P < 0.001), but not for mental retardation (odds ratio = 1.1, P = 0.78) or cerebral palsy (odds ratio = 1.3, P = 0.67). Children with macrocephaly had a high rate of comorbid diagnosis. We conclude that in children with developmental disabilities the presence of macrocephaly even when not associated with hydrocephalus is associated with an increased risk of seizures.

Cephalometry↗

Interrater reliability among epilepsy centers: multicenter study of epilepsy surgery.

PURPOSE: To measure the interrater reliability of presurgical testing and surgical decisions among epilepsy centers. METHODS: Seven centers participating in an ongoing, prospective multicenter study of resective epilepsy surgery agreed to conform to a detailed protocol regarding presurgical evaluation and surgery. To assess quality assurance, each center independently reviewed 21 randomly selected surgical cases for preoperative study lateralization and localization, and surgical decisions. Interrater reliability was assessed by using intraclass correlation coefficients (ICCs), validated for use with multiple raters, and calculated in a two-way random model based on absolute agreement. RESULTS: Agreement for ICC values: > or = 0.75, excellent; 0.60-0.74, good; 0.40-0.59, fair; < or = 0.39, poor. One center was excluded for missing data. Agreement was excellent for extracranial EEG lateralization (0.8039), magnetic resonance imaging (MRI) lateralization (0.9521) and localization (0.9130), Wada lateralization (0.9453), and intracranial EEG localization (0.7905). Agreement was good for extracranial EEG localization (0.7384) and neuropsychological testing lateralization (0.7178) and localization (0.6891). Consensus about the decision to perform intracranial monitoring was fair (0.5397), in part reflecting one center's tendency toward intracranial monitoring. Overall agreements on whether to perform surgery (0.8311) and specific surgery recommended (0.8164) were excellent. CONCLUSIONS: High interrater reliability among six epilepsy centers was present for interpretation of most components of presurgical testing. Although consensus for the decision to perform intracranial monitoring was only fair, agreements for the ultimate decision about resective surgery and specific choice of resection were excellent. We believe that this study demonstrates the feasibility of implementing multicenter protocols for neurologic management, especially those involving localization, as well as protocols combining study results with clinical decision making.

Electroencephalography↗

Update on the epidemiology and prognosis of pediatric epilepsy.

Epilepsy is among the most common serious neurologic disorders in childhood. Epidemiologic studies over the past few decades have greatly increased current knowledge of the incidence and prognosis of seizures. Newer epidemiologic studies have used population- or community-based cohorts, and careful attention has been given to etiology and specific epilepsy syndromes, the two most important factors affecting prognosis. Risk of epilepsy is highest in patients with an associated serious neurologic abnormality, such as mental retardation or cerebral palsy. More than two thirds of patients with childhood-onset epilepsy ultimately achieve remission. Of those attaining remission on medications, approximately 70% remain seizure free when medications are discontinued. Mortality is increased in patients with epilepsy, but the increased mortality risk in childhood-onset epilepsy is primarily seen in patients with neurologic abnormalities or intractable epilepsy. Although long-term seizure outcomes are generally favorable, childhood-onset epilepsy is associated with adverse long-term psychosocial outcomes, even in patients attaining remission. This review summarizes recent data on the epidemiology and prognosis of pediatric epilepsy.

Child↗

Febrile seizures.

Febrile seizures are the most common form of childhood seizures, occurring in 2 to 5% of children in the United States. Most febrile seizures are considered simple, although those with focal onset, prolonged duration, or that occur more than once within the same febrile illness are considered complex. Risk factors for a first febrile seizure, recurrence of febrile seizures, and development of future epilepsy are identifiable and varied. Children with febrile seizures encounter little risk of mortality and morbidity and have no association with any detectable brain damage. Recurrence is possible, but only a small minority will go on to develop epilepsy. Although antiepileptic drugs can prevent recurrent febrile seizures, they do not alter the risk of subsequent epilepsy. This has led to a changing view of how we approach the treatment of these common and largely benign seizures. This chapter will review the current understanding of the prognosis and management of febrile seizures.

Analgesics, Non-Narcotic↗