Determining the effects of antiepileptic drugs on cognitive function in pediatric patients with epilepsy

Long-term neuropsychological outcomes in children with febrile infection-related epilepsy syndrome (FIRES) treated with anakinra

Background

Febrile-infection related epilepsy syndrome (FIRES) is a rare epilepsy syndrome in which a previously healthy individual develops refractory status epilepticus in the setting of a preceding febrile illness. There are limited data regarding detailed long-term outcomes. This study aims to describe the long-term neuropsychological outcomes in a series of pediatric patients with FIRES.

Methods

This is a retrospective multi-center case series of pediatric patients with a diagnosis of FIRES treated acutely with anakinra who had neuropsychological testing at least 12 months after status epilepticus onset. Each patient underwent comprehensive neuropsychological evaluation as part of routine clinical care. Additional data collection included the acute seizure presentation, medication exposures, and outcomes.

Results

There were six patients identified with a median age of 11.08 years (IQR: 8.19-11.23) at status epilepticus onset. Anakinra initiation was a median of 11 days (IQR: 9.25-13.50) after hospital admission. All patients had ongoing seizures and none of the patients returned to baseline cognitive function with a median follow-up of 40 months (IQR 35-51). Of the five patients with serial full-scale IQ testing, three demonstrated a decline in scores over time. Testing results revealed a diffuse pattern of deficits across domains and all patients required special education and/or accommodations for academic learning.

Conclusions

Despite treatment with anakinra, neuropsychological outcomes in this series of pediatric patients with FIRES demonstrated ongoing diffuse neurocognitive impairment. Future research will need to explore the predictors of long-term neurocognitive outcomes in patients with FIRES and to evaluate if acute treatment interventions improve these outcomes.

Gray Matter Atrophy: The Impacts of Resective Surgery and Vagus Nerve Stimulation in Drug-Resistant Epilepsy

BACKGROUND

There is great concern for cognitive function after resective temporal lobe surgery for drug-resistant epilepsy. However, few studies have investigated postoperative anatomical changes, and the downstream effects of surgery are poorly understood. This study investigated volumetric changes after resective surgery and vagus nerve stimulation (VNS) for epilepsy.

METHODS

Preoperative and latest postoperative (mean, 28 months) structural T1 magnetic resonance imaging scans were retrospectively obtained for 43 patients: 27 temporal lobe resections (TLRs), 6 extratemporal lobe resections, and 10 VNS, undergoing surgery for drug-resistant epilepsy between 2012 and 2017. Automated volumetric analyses of predefined cortical gray matter and subcortical structures were performed. Preoperative and postoperative volumes were compared, and the effects of age, gender, operation type, resection laterality, selectivity, time since surgery, and seizure outcome on volumetric changes were analyzed.

RESULTS

After TLRs, there were reductions in contralateral hemispheric gray matter, temporal lobe, entorhinal cortex, parahippocampal, superior temporal, middle temporal, inferior temporal (P = 0.02), lingual, fusiform, precentral, paracentral, postcentral, pericalcarine gyri, and ipsilateral superior parietal gyrus. After VNS, there was bilateral atrophy in the thalamus, putamen, cerebellum, rostral anterior cingulate, posterior cingulate, medial orbitofrontal, paracentral, fusiform, and transverse temporal gyri. There was a significant effect of surgery type but no effect of age, gender, operation type, resection laterality, selectivity, time since surgery, and seizure outcome on contralateral hippocampal gray matter change.

CONCLUSION

This is the first study to demonstrate volumetric decreases in temporal and connected regions after TLRs and VNS. These results provide interesting insight into functional network changes.

Utility of EEG on attention deficit-hyperactivity disorder (ADHD)

OBJECTIVE

The aim of our study was to analyze electrophysiological findings in patient with Attention Deficit Hyperactivity Disorder (ADHD) by electroencephalography (EEG) recording, estimate the prevalence of epilepsy in ADHD population and assess its clinical characteristics.

METHODS

We conducted a retrospective and analytic study that concerned children with ADHD, followed for at least two-years in the Tunisian National Center for School and University Medicine (NCSUM). All patients recruited underwent at the diagnosis of ADHD, neurological examination and EEG recording in the department of Neurology of Charles Nicolle Hospital. Medical data including family history, ictal semiology and ADHD features were assessed.

RESULTS

Thirty patients were enrolled in our study. Mean age was 12.27 years with a sex ratio of 3.28. Mean age at diagnosis of ADHD was 6.6 years. Attention Deficit Hyperactivity Disordercombined subtype was seen in 18/30 patients, Hyperactive/ Impulsive subtype in 7/30 patients and Inattentive subtype in 5/30 patients. Epilepsy-disease was reported in 20% (Seizures preceded the diagnosis of ADHD in 3/6 cases and appeared after an average of 3.67 years in 3/6 cases). Mean age of seizure onset was 7 years. Seizure-types were generalized (motor 4/6 cases, absence-type (1/6 case)) and focal (1/6 case). Electroencephalography revealed Epileptiform discharges in 30% with frontal and left dominance. Interictal discharges were significantly associated with younger age of onset (p: 0.02), inattentive subtype (p: 0.04) and intellectual disability (p: 0.04). These discharges was not associated with epilepsy.

CONCLUSION

Our results have shown that epileptiform discharges could be used as risk factor for seizures and cognitive impairment which may influence outcome in ADHD population.

Intelligence quotient (IQ) among children with epilepsy: National epidemiological study - Sudan

BACKGROUND

Many studies of selected groups of children with epilepsy have demonstrated an association between epilepsy and cognitive deficits. The aim of this study was to assess the intellectual skills of children with epilepsy and to investigate the influence of gender, age at seizure onset, type of epilepsy, antiepileptic drug used, and control of epilepsy on their intellectual function.

METHODS

This is a descriptive prospective study in which one hundred and eighty-seven patients at school age (6-14 years) were recruited. Epilepsy was classified using the International League Against Epilepsy (ILAE) Commission on Classification and Terminology 2005-2009 report. An intelligence quotient (IQ) test was conducted to all patients using Stanford-Binet Fifth Edition (SB5)/Arabic version.

RESULTS

Eighty-eight (47.1%) patients had an average score on Full Scale IQ (FSIQ), 44 (23.5%) had low average, whereas 18 (9.6%) had borderline impaired or delayed score. In the nonverbal IQ (NVIQ) score, the majority 84 (44.9%) had average score. The performance of the patients in the nonverbal score is better than in the verbal score, which was found to be statistically significant (P-value = 0.01). The FSIQ score was negatively affected by younger age at onset of epilepsy, polytherapy, and uncontrolled seizures.

CONCLUSIONS

Most of children with epilepsy had an average FSIQ; uncontrolled seizure had worse effect on overall FSIQ and memory. Interventions to support children with epilepsy should focus on epilepsy management and school psychosocial domains.

Driving status of patients with generalized spike-wave on EEG but no clinical seizures

Generalized spike-wave discharges (SWDs) are the hallmark of generalized epilepsy on the electroencephalogram (EEG). In clinically obvious cases, generalized SWDs produce myoclonic, atonic/tonic, or absence seizures with brief episodes of staring and behavioral unresponsiveness. However, some generalized SWDs have no obvious behavioral effects. A serious challenge arises when patients with no clinical seizures request driving privileges and licensure, yet their EEG shows generalized SWD. Specialized behavioral testing has demonstrated prolonged reaction times or missed responses during SWD, which may present a driving hazard even when patients or family members do not notice any deficits. On the other hand, some SWDs are truly asymptomatic in which case driving privileges should not be restricted. Clinicians often decide on driving privileges based on SWD duration or other EEG features. However, there are currently no empirically-validated guidelines for distinguishing generalized SWDs that are "safe" versus "unsafe" for driving. Here, we review the clinical presentation of generalized SWD and recent work investigating mechanisms of behavioral impairment during SWD with implications for driving safety. As a future approach, computational analysis of large sets of EEG data during simulated driving utilizing machine learning could lead to powerful methods to classify generalized SWD as safe vs. unsafe. This may ultimately provide more objective EEG criteria to guide decisions on driving safety in people with epilepsy.

Epileptiform activity in the mouse visual cortex interferes with cortical processing in connected areas

Epileptiform activity is associated with impairment of brain function even in absence of seizures, as demonstrated by failures in various testing paradigm in presence of hypersynchronous interictal spikes (ISs). Clinical evidence suggests that cognitive deficits might be directly caused by the anomalous activity rather than by its underlying etiology. Indeed, we seek to understand whether ISs interfere with neuronal processing in connected areas not directly participating in the hypersynchronous activity in an acute model of epilepsy. Here we cause focal ISs in the visual cortex of anesthetized mice and we determine that, even if ISs do not invade the opposite hemisphere, the local field potential is subtly disrupted with a modulation of firing probability imposed by the contralateral IS activity. Finally, we find that visual processing is altered depending on the temporal relationship between ISs and stimulus presentation. We conclude that focal ISs interact with normal cortical dynamics far from the epileptic focus, disrupting endogenous oscillatory rhythms and affecting information processing.

Attention and executive functions in the early course of pediatric epilepsy

OBJECTIVE

Our prospective study aimed at exploring attention and executive functions in children with new-onset epilepsy prior to and during the early course of antiepileptic treatment. Sociodemographic and epilepsy-related factors were analyzed as potential predictors both of impaired cognitive functions as well as for changes in cognitive functioning in the early course of illness.

METHODS

From a total group of 115 children aged six to 17years without major disabilities, 76 children were assessed longitudinally with a screening tool for attention and executive functions (EpiTrack Junior®). Sociodemographic variables (gender, age at epilepsy onset, need of special education) and epilepsy-related variables (etiology of epilepsy, semiology of seizures, number of seizures) were considered as potential predictors for impaired functions prior to treatment and for deterioration/amelioration in cognitive functions in the early course.

RESULTS

Attention and executive functions of children with new-onset epilepsy were significantly more often impaired when compared with a healthy population, but less often when compared with children with chronic epilepsy. The majority of children showed stable cognitive functioning in the early course of treatment. The risk of impaired cognitive functions was significantly heightened when etiology of epilepsy was unknown or not classifiable. The chance for improvement of functioning was lowered by having a genetic epilepsy, or an unknown semiology of seizures.

CONCLUSIONS

Children with new-onset epilepsy are at high risk for impaired attention and executive functions even prior to antiepileptic treatment, especially when etiology of their epilepsy remains unclear. The high stability of cognitive functioning in the early course can be used in counseling of families who worry about negative side effects of drug treatment. Finally, a systematic assessment of cognitive functions in children with new-onset epilepsy is necessary to detect subtle deficits in the early course and adjust treatment accordingly.

Epilepsy and attention-deficit hyperactivity disorder: links, risks, and challenges

Attention-deficit hyperactivity disorder (ADHD) has a prevalence rate of 7%-9% in the general population of children. However, in children with epilepsy, ADHD has been found to be present in 20%-50% of patients. This paper provides a review of ADHD prevalence in pediatric epilepsy populations and reviews data on specific symptom presentation and attention deficits in patients with epilepsy. This paper also reviews evidence-based treatments for ADHD and specifically the treatment of ADHD as a comorbid condition in children with epilepsy.

An examination of the Allocation of Treatment Responsibility scale in adolescents with epilepsy

The purpose of the current study was to examine the psychometric properties of the adapted Allocation of Treatment Responsibility (ATR) scale and the distribution of tasks related to oral medication and clinic and laboratory visits in a sample of adolescents with epilepsy. Adolescents with epilepsy (N = 50; ages 13-17 years) and their caregivers completed the adapted ATR and a measure of medication management. Internal consistency for the adapted ATR was strong (total and subscale range: 0.75-0.97). Validity was partially supported by significant correlations between adolescent age and ATR oral medication responsibility for both respondent measures. Allocation of Treatment Responsibility total scores were not associated with adherence to medications and clinic appointments. Initial findings are promising and have important implications for assessing the distribution of treatment responsibility among adolescents with epilepsy and their families.

Nutritional and socio-economic determinants of cognitive function and educational achievement of Aboriginal schoolchildren in rural Malaysia

A community-based cross-sectional study was carried out among Aboriginal schoolchildren aged 7–12 years living in remote areas in Pos Betau, Pahang, Malaysia to investigate the potential determinants influencing the cognitive function and educational achievement of these children. Cognitive function was measured by intelligence quotient (IQ), while examination scores of selected school subjects were used in assessing educational achievement. Blood samples were collected to assess serum Fe status. All children were screened for soil-transmitted helminthes. Demographic and socio-economic data were collected using pre-tested questionnaires. Almost two-thirds (67·6 %) of the subjects had poor IQ and most of them (72·6 %) had insufficient educational achievement. Output of the stepwise multiple regression model showed that poor IQ was significantly associated with low household income which contributed the most to the regression variance (r2 0·059; P = 0·020). Low maternal education was also identified as a significant predictor of low IQ scores (r2 0·042; P = 0·043). With educational achievement, Fe-deficiency anaemia (IDA) was the only variable to show significant association (r2 0·025; P = 0·015). In conclusion, the cognitive function and educational achievement of Aboriginal schoolchildren are poor and influenced by household income, maternal education and IDA. Thus, effective and integrated measures to improve the nutritional and socio-economic status of rural children would have a pronounced positive effect on their education.

Epilepsy in children with attention-deficit/hyperactivity disorder

Previous studies have suggested a higher incidence of symptoms of attention-deficit/hyperactivity disorder (ADHD) in children with epilepsy, but few have investigated epilepsy in children with ADHD. The objective here was to compare the incidence and characteristics of epilepsy among population-based, research identified cohorts of children with (n = 358) and without ADHD (n = 728), based on medical record review to age 20 years. Data abstracted included characteristics of seizures, testing, and treatment. Cases were 2.7 times more likely than controls to have epilepsy (95% CI = 0.94-7.76; P = 0.066), had earlier seizure onset (median age, 5.5 vs 15 years; P = 0.020), and exhibited a trend toward more frequent seizures (more than monthly, 63% vs 17%). Among children who met the research criteria for ADHD, those with epilepsy tended to be less likely to have received a clinical diagnosis of ADHD (63% vs 89%; P = 0.052) or to be treated with stimulants (50% vs 85%; P = 0.025). The findings suggest a strong trend toward a higher incidence of epilepsy among children with ADHD than among children without ADHD. Epilepsy in children with ADHD appears to be more severe than in those without. Finally, there appears to be a reluctance to diagnose and initiate treatment for ADHD in children with epilepsy.

Ethosuximide, valproic acid, and lamotrigine in childhood absence epilepsy

BACKGROUND

Childhood absence epilepsy, the most common pediatric epilepsy syndrome, is usually treated with ethosuximide, valproic acid, or lamotrigine. The most efficacious and tolerable initial empirical treatment has not been defined.

METHODS

In a double-blind, randomized, controlled clinical trial, we compared the efficacy, tolerability, and neuropsychological effects of ethosuximide, valproic acid, and lamotrigine in children with newly diagnosed childhood absence epilepsy. Drug doses were incrementally increased until the child was free of seizures, the maximal allowable or highest tolerable dose was reached, or a criterion indicating treatment failure was met. The primary outcome was freedom from treatment failure after 16 weeks of therapy; the secondary outcome was attentional dysfunction. Differential drug effects were determined by means of pairwise comparisons.

RESULTS

The 453 children who were randomly assigned to treatment with ethosuximide (156), lamotrigine (149), or valproic acid (148) were similar with respect to their demographic characteristics. After 16 weeks of therapy, the freedom-from-failure rates for ethosuximide and valproic acid were similar (53% and 58%, respectively; odds ratio with valproic acid vs. ethosuximide, 1.26; 95% confidence interval [CI], 0.80 to 1.98; P=0.35) and were higher than the rate for lamotrigine (29%; odds ratio with ethosuximide vs. lamotrigine, 2.66; 95% CI, 1.65 to 4.28; odds ratio with valproic acid vs. lamotrigine, 3.34; 95% CI, 2.06 to 5.42; P<0.001 for both comparisons). There were no significant differences among the three drugs with regard to discontinuation because of adverse events. Attentional dysfunction was more common with valproic acid than with ethosuximide (in 49% of the children vs. 33%; odds ratio, 1.95; 95% CI, 1.12 to 3.41; P=0.03).

CONCLUSIONS

Ethosuximide and valproic acid are more effective than lamotrigine in the treatment of childhood absence epilepsy. Ethosuximide is associated with fewer adverse attentional effects. (ClinicalTrials.gov number, NCT00088452.)

Cognitive effects of antiepileptic drugs

Antiepileptic drugs (AEDs) can adversely affect cognitive function by suppressing neuronal excitability or enhancing inhibitory neurotransmission. The main cognitive effects of AEDs are impaired attention, vigilance, and psychomotor speed, but secondary effects can manifest on other cognitive functions. Although the long-term use of AEDs can obviously elicit cognitive dysfunction in epilepsy patients, their cognitive effects over short periods of up to a year are inconclusive due to methodological problems. In general, the effects on cognition are worse for older AEDs (e.g., phenobarbital) than for placebo, nondrug condition, and newer AEDs. However, topiramate is the newer AED that has the greatest risk cognitive impairment irrespective of the comparator group. Since the cognitive impact of AEDs can be serious, clinicians should be alert to adverse events by evaluating cognitive function using screening tests. Adverse cognitive events of AEDs can be avoided by slow titration to the lowest effective dosage and by avoiding polytherapy.

Comparison of cognitive effects of lamotrigine and oxcarbazepine in epilepsy patients

BACKGROUND AND PURPOSE

This study compared the cognitive effects of 1 year of treatment with lamotrigine (LTG) and oxcarbazepine (OXC) in epilepsy patients.

METHODS

This retrospective study investigated 60 epilepsy patients undergoing neuropsychological tests who were either newly diagnosed or untreated in the preceding 6 months. The cognitive function in 30 patients receiving LTG monotherapy and 30 age-matched patients receiving OXC monotherapy was compared after 1 year. The neuropsychological scores at baseline and all of the epilepsy-relevant variables except seizure type did not differ between the groups. The mean daily dosages of LTG and OXC at 1 year were 93 mg and 825 mg, respectively.

RESULTS

The posttreatment list-learning performance was better in the LTG group than in the OXC group (p<0.05). The incidence of cognitive complaints did not differ between the two groups. The list-learning performance and Trail Making Test scores were better in each group after treatment.

CONCLUSIONS

LTG and OXC monotherapies have similar, slightly beneficial effects on cognitive function, and are probably not harmful.

Antiepileptic drug treatment in children

Epilepsy is one of the most common neurological disorders of childhood, and antiepileptic drugs represent the main component of its treatment. The current emphasis in epilepsy treatment is to improve quality of life, not only by suppressing seizure, but also by minimizing the side effects of medications. The last 15 years have been characterized by significant advances in the development of new agents that have helped us to get closer to this goal. Knowledge of the essential properties, key indications and interactions of each antiepileptic drug will help to optimize efficacy and reduce adverse reactions. Age is also a determining factor of the epilepsy phenotype and its treatment. This review addresses the principles of pediatric epilepsy treatment, summarizes the profile of each of the commonly used antiepileptic drugs, and provides a treatment paradigm for particular seizures and epilepsy syndromes of childhood.

Cognitive Effects of Low-dose Topiramate Compared with Oxcarbazepine in Epilepsy Patients

Background and Purpose

Low-dose topiramate (TPM) monotherapy has recently been found effective for seizure control in newly diagnosed epilepsy. In higher dosages, TPM has been associated with relatively high rates of adverse cognitive effects; similar side effects have been seen after rapid titration or polytherapy. However, its cognitive effects during low-dose monotherapy have not been established. We evaluated the cognitive effects of low-dose TPM compared with oxcarbazepine (OXC), a drug that does not appear to affect cognitive function.

Methods

Cognitive tests and subjective complaints of 30 patients with low-dose TPM monotherapy (50-200 mg/day) were retrospectively compared with those of 30 patients with OXC monotherapy at 1 year of medication. The two groups did not differ with respect to epilepsy-relevant variables, nor on baseline neuropsychological tests.

Results

The TPM group showed a significant difference in the performance of delayed word recall (P<0.05), backward digit span (P<0.01), and verbal fluency (P<0.05) compared with the OXC group. The TPM group showed worse performances of digit span and verbal fluency. The OXC group showed better performances of delayed word recall. The incidence of cognitive complaints was higher in the TPM group (50%) than in the OXC group (20%) (P<0.05). These cognitive effects shown in the TPM group were dose-related. The cognitive dysfunction was trivial with patients taking 50 mg/day TPM.

Conclusions

Even at low-dose, TPM has a negative effect on working memory and verbal fluency compared with OXC. It can be demonstrated at 1 year of treatment.

Poor school performance

Education is one of the most important aspects of human resource development. Poor school performance not only results in the child having a low self-esteem, but also causes significant stress to the parents. There are many reasons for children to under perform at school, such as, medical problems, below average intelligence, specific learning disability, attention deficit hyperactivity disorder, emotional problems, poor socio-cultural home environment, psychiatric disorders and even environmental causes. The information provided by the parents, classroom teacher and school counselor about the child's academic difficulties guides the pediatrician to form an initial diagnosis. However, a multidisciplinary evaluation by an ophthalmologist, otolaryngologist, counselor, clinical psychologist, special educator, and child psychiatrist is usually necessary before making the final diagnosis. It is important to find the reason(s) for a child's poor school performance and come up with a treatment plan early so that the child can perform up to full potential.