Search PubMed⌕ Search

Biomedical subjects

A T Berg

Publications and source records attributed to A T Berg.

At least 37 records · Page 2Linked to original sources

Relationships between seizure severity and health-related quality of life in refractory localization-related epilepsy.

PURPOSE: To evaluate relationships between self-report measures of seizure severity and health-related quality of life (HRQOL) in people with refractory localization-related epilepsy. METHODS: A sample of 340 adults enrolled in a seven-center, prospective study of resective epilepsy surgery completed baseline questionnaires that included the Quality of Life in Epilepsy (QOLIE)-89 and a seven-item adaptation of the National Hospital Seizure Severity Scale. Associations between QOLIE-89 summary measures and both the total seizure severity scale score and individual seizure severity items were assessed, after adjustment for seizure frequency. RESULTS: The seizure severity measure had adequate scale score variability and reliability in this sample. Correlations between individual items in the scale did not exceed 0. 43. Product-moment partial correlations between the seizure severity scale and QOLIE-89 summary measures ranged from -0.17 to -0.29 (all p values <0.01). Of the seven seizure severity items, the average time before individuals perceived they were "really back to normal" after their seizures was broadly related to all domains of HRQOL (r values ranged from -0.16 to -0.30; p values <0.01). Severity of injury during seizures was the only other item having more than minimal associations with HRQOL, and it was selectively related to the physical health measure. Higher frequency of falls during seizures was modestly related to less employment. CONCLUSIONS: This seizure severity measure assesses constructs that are generally distinct from HRQOL, except for moderate and broad associations between HRQOL and patient's perceptions of the average duration of recovery time after seizures. Recovery time may potentially be a useful clinical indicator of seizure severity that reflects meaningful impairment of HRQOL in adults with frequent seizures.

Adolescent↗

How well can epilepsy syndromes be identified at diagnosis? A reassessment 2 years after initial diagnosis.

PURPOSE: Epilepsy syndromes can be identified very early in the course of a seizure disorder. It is unclear how accurate and resilient such early classifications are. We compared the classification of epilepsy syndromes made previously on the basis of information available at diagnosis with those made 2 years later in a cohort of children with newly diagnosed epilepsy. METHODS: Children (n = 613) were prospectively identified at the time of initial diagnosis by participating physicians in Connecticut between 1993 and 1997. Classification of epilepsy syndrome according to International League Against Epilepsy guidelines was made previously based on all relevant information available at diagnosis. All cases were reclassified again after 2 years of additional evidence had accumulated. The distributions of syndromes at diagnosis and at 2 years are compared and reasons for changes examined. RESULTS: After 2 years, syndromes remained the same in 86.3% of the cohort and changes occurred in 13.7% (n = 84). Evolution of the syndrome occurred in 24 children (3.9%), and rectification to the initial diagnosis occurred in 60 children (9.8%). The most common scenario for evolution of a syndrome was from West syndrome (n = 5), undetermined (n = 4), or symptomatic localization-related epilepsy (n = 3) to the Lennox-Gastaut syndrome. The most common rectification of initial classifications involved incompletely classified syndromes (cryptogenic localization-related and undetermined syndromes; n = 36). In a few instances, a fully specified syndrome was reclassified to another apparently unrelated syndrome. In these cases, initial information at diagnosis had been difficult to interpret. CONCLUSIONS: Epilepsy syndromes can, for the most part, be identified at the time of initial diagnosis. Two years later, rectifications were made in only 9.8% of cases, and most of these involved syndromes that represented incomplete classifications in the first place. Significant changes were rare. The International League Against Epilepsy classification of the epilepsies can be meaningfully applied in epidemiological studies of newly diagnosed pediatric epilepsy.

Age of Onset↗

Neuroimaging in children with newly diagnosed epilepsy: A community-based study.

BACKGROUND: Neuroimaging is generally considered a part of the evaluation of seizures and epilepsy. There is limited information about its current use in the initial evaluation of pediatric epilepsy and about its yield during the initial diagnosis of epilepsy. We describe the patterns in the use and yield of diagnostic imaging in children with newly diagnosed epilepsy in a community-based study. METHODS: Children were recruited when first diagnosed with epilepsy by participating physicians in Connecticut (1993-1997). Definitions for etiology and underlying epilepsy syndromes are as published by the International League Against Epilepsy. RESULTS: Of 613 children, 488 (79.6%) had imaging: 388 (63. 3%) magnetic resonance imaging, 197 (32.1%) computed tomography scans, and 97 (15.8%) both. Half of children with idiopathic generalized epilepsy had imaging studies compared with 70% to 100% of children with other forms of epilepsy, depending on the specific type. Etiologically relevant abnormalities were found in 62 (12.7% of those imaged). Fourteen of these children had otherwise completely normal presentations and histories. Their abnormalities included tuberous sclerosis (N = 4), tumors (N = 2), an arteriovenous malformation later diagnosed as a tumor, a cavernous angioma, cerebral malformations (N = 3), and other abnormalities (N = 3). Thirteen of the 14 had partial seizures and 12 had focal electroencephalographic (EEG) findings. Only 1 had neither. CONCLUSIONS: In children with newly diagnosed epilepsy, neuroimaging reveals a small but significant number of serious abnormalities not previously suspected. Most of these children have partial seizures or focal EEG abnormalities. Neuroimaging should be considered during the evaluation of children with newly diagnosed epilepsy, especially for those with neurologic deficits or partial seizures or focal EEG abnormalities that are not part of an idiopathic localization-related epilepsy syndrome.

Child↗

Predictors of multiple seizures in a cohort of children prospectively followed from the time of their first unprovoked seizure.

The objective of this study was to assess the risk of multiple recurrences after an initial seizure recurrence in childhood. In a prospective study, 407 children were followed for a mean of 9.6 years from the time of their first unprovoked seizure. Data regarding each seizure recurrence were obtained and analyzed using statistical methods for survival analysis. The cumulative risk of a second seizure was 29%, 37%, 43%, and 46% at 1, 2, 5, and 10 years, respectively. Of the 182 children who experienced a second seizure, 131 (72%) experienced a third seizure, 105 (58%) have had 4 or more seizures, and 52 (29%) have experienced 10 or more seizures. The cumulative risk of a third seizure was 57%, 63%, and 71% at 1, 2, and 5 years, respectively, after the second seizure. After a third seizure, the cumulative risk of another seizure was 69%, 72%, and 81% at 1, 2, and 5 years, respectively. After a second seizure, factors associated with an increased risk of additional recurrences included a remote symptomatic etiology (rate ratio = 1.7) and the occurrence of a second seizure within 6 months of the first seizure (rate ratio = 1.7). After a second seizure, the risk of subsequent seizures was greater than 50% even in the lowest risk group. With the exception of etiology, factors associated with an increased risk of multiple recurrences after the initial seizure were different than those associated with multiple recurrences after a second seizure. Factors associated with multiple recurrent seizures may be different than those associated with an initial recurrence. As most patients who experience a second seizure experience further seizures, these data suggest that two seizures are a sufficient epidemiological criterion for the definition of epilepsy.

Adolescent↗

Childhood-onset epilepsy with and without preceding febrile seizures.

OBJECTIVE: To identify characteristics in children with epilepsy that differ between those who did versus did not have a history of preceding febrile seizures. BACKGROUND: Febrile seizures precede epilepsy in 10 to 15% of children. Little is known about the specific types of epilepsy associated with febrile seizures. METHODS: In a community-based, prospectively identified cohort of children, the association between prior febrile seizures and characteristics of the children's epilepsy (seizure type, epilepsy syndrome, age at onset, underlying etiology, family history) were examined for 524 of the children who were aged > or =1 year at onset of epilepsy. RESULTS: Seventy-three (13.9%) had febrile seizures. Children with febrile seizures were more likely to have a first-degree or a second-higher-degree relative with febrile seizures and less likely to have childhood absence epilepsy and absence seizures compared with children without febrile seizures. This was especially true for simple febrile seizures. There was no specific association with localization-related forms of epilepsy. Complex, but not simple, febrile seizures were associated with younger age at onset of epilepsy. There was no evidence that focal or prolonged febrile seizures were associated with localization-related epilepsy or temporal lobe epilepsy per se. Of the three children whose initial MRIs demonstrated hippocampal atrophy, none had a history of febrile seizures. CONCLUSIONS: At the time of diagnosis, febrile seizures are not specifically related to temporal lobe epilepsy or localization-related epilepsy in general. A genetic component for febrile seizures is suggested by its positive associations with family history, especially for simple febrile seizures. Complex febrile seizures represent an underlying age-dependent susceptibility.

Age of Onset↗

Treatment of newly diagnosed pediatric epilepsy: a community-based study.

OBJECTIVE: To determine the patterns and frequency of treatment and use of specific drugs for newly diagnosed pediatric epilepsy. DESIGN AND SETTING: Prospective, community-based study. Children were recruited from physicians in Connecticut from 1993 to 1997. PATIENTS: Children aged 1 month through 15 years at the time of their first seizure, who had 2 or more unprovoked seizures, and who were newly diangosed during the recruitment period were eligible. MAIN OUTCOME MEASURE: Initiation of treatment at diagnosis and within 1 year after diagnosis of epilepsy. RESULTS: Of 613 children, 482 (78.6%) were treated at the time of initial diagnosis. By 6 months another 10.3% were treated, and by 12 months 90% of the cohort had been treated. The most commonly prescribed antiepileptic drug (AED) was carbamazepine (38.8%) followed by sodium valproate (18.4%). Only 1 child received an investigational drug and none received any of the most recently approved drugs as a first AED. Children with idiopathic and secondarily generalized forms of epilepsy were most likely to be treated (90%-100%), whereas children with idiopathic localization-related epilepsy were least likely to be treated (50.8%). Approximately 80% of those with other forms of epilepsy were treated at the time of diagnosis. Use of specific medications reflected current guidelines and recommendations for treatment of specific seizure types and syndromes. CONCLUSIONS: In Connecticut, approximately 20% of children with epilepsy are not treated at the time of initial diagnosis, and around 10% continue to be untreated after 1 year. This most likely reflects the increased understanding of the nature of pediatric epilepsy and concerns regarding the adverse effects of AEDs. The most commonly used first drugs are carbamazepine and valproate. Follow-up of this cohort may help provide information to guide the use of recently approved AEDs.

Adolescent↗

Status epilepticus in children with newly diagnosed epilepsy.

Status epilepticus (SE) constitutes a neurological emergency and may be of prognostic value in individuals with epilepsy. Little is known about the associations between other prognostic factors in epilepsy and the occurrence of SE. The following study examines associations between clinical characteristics of children with newly diagnosed epilepsy and the occurrence of SE when epilepsy is first diagnosed. Children were recruited prospectively from the practices of physicians throughout Connecticut. Information was collected via standardized interviews with parents and review of pertinent records. Analyses were performed for any SE, unprovoked SE only, and previous provoked SE. Of 613 children, 56 (9.1%) had one or more episodes of SE by the time the diagnosis of epilepsy was established. Factors correlated with SE during an unprovoked seizure were partial seizures and previous craniotomy. For SE during a provoked seizure, correlates were primarily young age at onset of epilepsy and nonidiopathic epilepsy syndrome. To date, subsequent SE has occurred in 4.3% of children without and in 19.6% of those with SE at diagnosis. By the time epilepsy is first diagnosed in children, SE has already occurred in a substantial minority. It is correlated with specific clinical characteristics in the children, which differ depending on whether the SE was provoked or unprovoked. SE has a high risk of recurring.

Child↗

Classification of childhood epilepsy syndromes in newly diagnosed epilepsy: interrater agreement and reasons for disagreement.

PURPOSE: The International League Against Epilepsy (ILAE) classification of the epilepsies is in increasingly widespread use. The following analysis was done to assess the interrater agreement in classifying epilepsy syndromes in children with newly diagnosed epilepsy. METHODS: In a prospective, community-based study, 613 children with newly diagnosed epilepsy were recruited. Based on information available at diagnosis or generated as part of the initial diagnostic assessment, three pediatric neurologists independently classified epilepsy syndromes. Interrater agreement was assessed with kappa. RESULTS: Interrater agreement was extremely good, with kappa scores > or = 0.80 for almost all comparisons. Relatively limited quality of the EEG and seizure information in some cases, as well as discrepancies between the two, were associated with a tendency for more disagreement. CONCLUSIONS: A high degree of interrater agreement was obtained in this study, indicating that the system for classifying syndromes can be meaningfully used in a community-based sample. Quality of the information, which is often, by necessity, less than optimal in newly diagnosed epilepsy, is a potential barrier to identification of syndromes. A substantial proportion of children were classified into relatively nonspecific syndromes. Over time, additional information may come to light to allow more precise identification of their forms of epilepsy. In an epidemiologic setting, the ILAE classification of the epilepsies can be successfully used with a high degree of reliability to classify newly diagnosed epilepsy in children.

Age Factors↗

Newly diagnosed epilepsy in children: presentation at diagnosis.

PURPOSE: The current understanding of epilepsy has changed significantly in the past 2 decades. This report presents a description of newly diagnosed childhood-onset epilepsy, with a special emphasis on epilepsy syndromes, in a large, prospectively ascertained community-based cohort evaluated and diagnosed in the mid-1990s. METHODS: Children, aged 0 through 15 years at the time of the first seizure, were prospectively identified at the time of diagnosis of epilepsy through the practices of 16 of the 17 child neurologists in Connecticut as well as five adult neurologists and seven pediatricians from January 1993 through December 1997. Parents were interviewed, and all relevant medical records were reviewed. Classification of seizures and of epilepsy syndromes was done for each child by each of three pediatric neurologists. Discrepancies were resolved in conference. RESULTS: A total of 613 children was recruited into the study. The median age at time of the first seizure was 5.3 years. Half the cohort was boys. Eighteen percent had a remote symptomatic etiology. Epilepsy syndromes were classifiable in all but four children, although some syndromes are, by definition, relatively nonspecific. In this childhood-onset cohort, 58.6% of the syndromes were localization related, 29.0% generalized, and 12.4% undetermined as to whether focal or generalized. Benign rolandic epilepsy occurred in 10% of the cohort. Primarily generalized syndromes accounted for 20.6%, with childhood absence being the single most common syndrome in this subgroup (12.1% of the cohort). Secondarily generalized syndromes accounted for 8.5% of the total, with infantile spasms being the most common in this grouping (3.9% of the cohort). CONCLUSIONS: This study presents a description of childhood- and adolescent-onset epilepsy as it is diagnosed and evaluated in the 1990s in one state in the United State and based on current classification guidelines. The results should be generalizable to the rest of the country. The prognostic value of early identification of epilepsy syndromes will be determined through subsequent follow-up of this cohort.

Age Factors↗

Distribution of epilepsy syndromes in a cohort of children prospectively monitored from the time of their first unprovoked seizure.

PURPOSE: To assess the distribution of epilepsy syndromes and their stability in children. METHODS: A cohort of 407 children with a first unprovoked seizure was prospectively recruited and followed up for a mean of 9.4 years. Etiology and epilepsy syndromes were classified by using the International League Against Epilepsy (ILAE) guidelines in the 182 children with two or more seizures. Classification was done both at time of second seizure and at last follow-up. Two-year terminal remission also was analyzed by etiology and epilepsy syndrome. RESULTS: Etiology of epilepsy syndromes was idiopathic in 45 (25%), cryptogenic in 89 (49%), and remote symptomatic in 48 (26%). In the initial classification, 114 (63%) children had a localization-based epilepsy syndrome including idiopathic in 26, cryptogenic in 34, and symptomatic based on localization or etiology in 54. Twenty-one (12%) children had a generalized epilepsy syndrome, including 19 with primary generalized epilepsy. Forty-seven (26%) cases were in the category of undetermined if focal or generalized. At last follow-up, there was a change in either etiology (n = 16) or the final epilepsy syndrome classification (n = 33) or both (n = 15) in 34 (19%) cases. At time of last follow-up, 144 (79%) of the children with epilepsy were in 2-year terminal remission, and 108 (59%) were in 2-year terminal remission without medications. Factors associated with a favorable prognosis included an idiopathic or cryptogenic etiology and having a localization-based idiopathic epilepsy syndrome. CONCLUSIONS: After two seizures, childhood-onset epilepsy can be classified by etiology and epilepsy syndrome. Prognosis is favorable in the majority of cases. However, the apparent syndrome may change with longer follow-up. The ability to classify these cases early in the clinical course is important if they are to be used for prognostic purposes.

Adolescent↗

Multivariable prediction of seizure outcome one year after resective epilepsy surgery: development of a model with independent validation.

PURPOSE: To identify predictors of seizure-outcome after epilepsy surgery and validate the findings in an independent series of patients. To use the results to develop a predictive model. METHODS: Sequential patients undergoing resective surgery for medically intractable epilepsy were identified at Yale New Haven Hospital (1987-1990, group 1) and Columbia Presbyterian Hospital (1991-1994, group 2). Information about seizure outcome and predictors of outcome was obtained from medical chart review. Good seizure-outcome was defined as having been seizure-free for one year beginning with discharge from the hospital. Multiple logistic regression was used to develop a model of predictors in group 1. It was then validated in group 2. RESULTS: There were 133 patients in group 1 and 81 in group 2. In a multivariable analysis, independent predictors of outcome in group 1 were presence of mesial temporal sclerosis based on postsurgical pathological analysis (MTS) (relative risk (RR) = 1.47), having a known underlying etiology (RR = 1.32), and partial seizures only (RR = 1.17). In group 2, the findings for each factor were similar to those in group 1: MTS, RR = 1.49; etiology, RR = 1.32; and partial seizures, RR = 1.24. Used in combination, these three factors can identify patients with nearly a 100% chance of being seizure-free (all three factors present) versus less than a 50% chance (none of the three factors present). CONCLUSIONS: With independent validation of the findings, we can be reasonably certain that the three factors identified in this analysis are meaningful and generalizable predictors of seizure outcome following epilepsy surgery. Use of predictive models should be considered in future studies to convert study results into clinically relevant statements about a particular patient's likelihood of surgical success.

Adolescent↗

Seizures with fever after unprovoked seizures: an analysis in children followed from the time of a first febrile seizure.

PURPOSE: To determine how the onset of unprovoked seizures influences recurrence of seizures with fever in children followed from the time of a first febrile seizure. METHODS: In a prospective cohort of children (n = 428) identified at the time of a first febrile seizure, predictors of a second seizure with fever were identified. The occurrence of a first unprovoked seizure was treated as a time-dependent covariate in a Cox regression model rather than as a censoring point as it traditionally has been in the past. RESULTS: One hundred forty-three (33.4%) children had further seizures. Seven had further seizures with fever only after onset of unprovoked seizures. After adjustment was made for the four previously described predictors of recurrent febrile seizures (age at onset, family history, height of fever, and duration of fever), the onset of unprovoked seizures was associated with a rate ratio of 3.47 (p = 0.0015), indicating a large increase in the risk of further seizures with fever after onset of unprovoked seizures. CONCLUSIONS: Young children who develop unprovoked seizures after a febrile seizure are at substantial risk for further seizures with fever. This may represent part of the spectrum of benign febrile seizures or it may represent the so-called "epilepsy triggered by fever" spectrum. It affects only a small proportion of children with febrile seizures; however, in some children, it may be useful information to consider when making treatment decisions.

Age of Onset↗

Predictors of recurrent febrile seizures. A prospective cohort study.

OBJECTIVES: To define the risk and identify predictors of single and multiple recurrent febrile seizures. METHODS: Children (n = 428) with first febrile seizures were prospectively identified and followed for 2 or more years. Parents were interviewed soon after their children's first febrile seizure and were called every 3 months to ascertain recurrent febrile seizures. Medical records of first and recurrent seizures were reviewed for additional information. RESULTS: A total of 136 children (31.8%) experienced recurrent seizures: 73 (17.1%) had only 1 recurrence, 38 (8.9%) had 2 recurrences, and 25 (5.8%) had 3 or more recurrences. Young age at onset, a history of febrile seizures in a first-degree relative, low degree of fever while in the emergency department, and a brief duration between the onset of fever and the initial seizure were strong independent predictors of recurrent febrile seizures. With these 4 factors combined, it is possible to define groups of children having very high and very low probabilities of having any recurrences (> 70% vs < 20%), having 2 or more recurrences (> 60% vs < 10%), and having 3 or more recurrence (12% vs about 0%). In children who had at least 1 recurrence, age at the time of the first recurrence and a family history of epilepsy were predictors of subsequent recurrences. CONCLUSIONS: In children who have had a first febrile seizure, recurrences are common. The risk for 1 or more recurrences can be meaningfully predicted at the time of the initial febrile seizure with a combination of the 4 factors identified in this study.

Child, Preschool↗

Do seizures beget seizures? An assessment of the clinical evidence in humans.

For more than a century, epilepsy was characterized as a chronic disease, with little chance of remission or cure. It was also considered a progressive disease in which seizures led to more seizures. Experimental work in animals provided additional support for the notion that seizures could beget seizures. However, the earliest clinical observations in humans were based on highly selected, largely refractory patients. Furthermore, the experimental work in animals bore little relation to naturally occurring seizures and epilepsy in humans. Evidence from multiple sources regarding the nature and natural history of seizures and epilepsy in humans has repeatedly demonstrated that in most cases of occurrence of seizures itself does not influence the long-term outcome of epilepsy. Consequently, interventions to prevent seizures early in the course of a seizures disorder do not alter the natural history of seizure disorders with respect to whether remission will occur in the long term. That outcome is largely predetermined by other factors, many of which are not currently amenable to intervention. In some rare syndromes, deterioration is progressive. In these instances, it is the underlying syndrome, not the seizures, that is primarily responsible for the deterioration. In addition, extremely prolonged seizures (which are rare) may also directly cause damage. These are exceptions rather than, as previously believed, the rule. The available human data strongly suggest that seizures do not beget seizures and that epilepsy in humans is usually not a progressive disorder.

Anticonvulsants↗

The epidemiology of epilepsy. Past, present, and future.

Much has been learned from epidemiologic studies about the frequency, causes, natural history, and prognosis of epilepsy and other seizure disorders. This knowledge has resulted in significant changes in the clinical management of individuals who have seizures and epilepsy. Recent changes in the known causal factors and diagnostic technologic advances, among other factors, will affect the epidemiology and prognosis of epilepsy. Continued epidemiologic monitoring of this common neurologic condition is necessary to ensure an accurate understanding of the current forms of the disorder.

Adolescent↗

Complex febrile seizures.

In the context of a prospective cohort study, we examined the associations between individual complex features of both first (n = 428) and recurrent (n = 240) febrile seizures and factors shown to predict outcome in children with febrile seizures. Thirty-five percent of first and 33% of recurrent febrile seizures had one or more complex features (focal onset, duration > or = 10 min, or multiple seizures during the illness episode). There were strong correlations between focality and prolonged duration for both first and recurrent febrile seizures. A low fever at the time of the seizure was marginally associated with prolonged duration. Most factors associated with either recurrent febrile seizures or subsequent unprovoked seizures were not associated with either the initial seizure being complex or the likelihood that a recurrence would be complex. However, the children with recurrent febrile seizures, complex features tended to repeat. This factor was statistically significant and particularly striking for prolonged duration. Genetic or other constitutional factors may explain why the prolonged feature recurs. Eleven (2.5%) children had three or four risk factors for recurrent febrile seizure that was prolonged. This very small group of children may be candidates for abortive therapy to be administered at the onset of a recurrent seizure.

Child↗