Summary Background Many women of childbearing potential take antiepileptic drugs, but the cognitive effects of fetal exposure are uncertain. We aimed to assess effects of commonly used antiepileptic ...drugs on cognitive outcomes in children up to 6 years of age. Methods In this prospective, observational, assessor-masked, multicentre study, we enrolled pregnant women with epilepsy on antiepileptic drug monotherapy (carbamazepine, lamotrigine, phenytoin, or valproate) between October, 1999, and February, 2004, at 25 epilepsy centres in the UK and the USA. Our primary outcome was intelligence quotient (IQ) at 6 years of age (age-6 IQ) in all children, assessed with linear regression adjusted for maternal IQ, antiepileptic drug type, standardised dose, gestational birth age, and use of periconceptional folate. We also assessed multiple cognitive domains and compared findings with outcomes at younger ages. This study is registered with ClinicalTrials.gov , number NCT00021866. Findings We included 305 mothers and 311 children (six twin pairs) in the primary analysis. 224 children completed 6 years of follow-up (6-year-completer sample). Multivariate analysis of all children showed that age-6 IQ was lower after exposure to valproate (mean 97, 95% CI 94–101) than to carbamazepine (105, 102–108; p=0·0015), lamotrigine (108, 105–110; p=0·0003), or phenytoin (108, 104–112; p=0·0006). Children exposed to valproate did poorly on measures of verbal and memory abilities compared with those exposed to the other antiepileptic drugs and on non-verbal and executive functions compared with lamotrigine (but not carbamazepine or phenytoin). High doses of valproate were negatively associated with IQ ( r =–0·56, p<0·0001), verbal ability ( r =–0·40, p=0·0045), non-verbal ability ( r =–0·42, p=0·0028), memory ( r =–0·30, p=0·0434), and executive function ( r =–0·42, p=0·0004), but other antiepileptic drugs were not. Age-6 IQ correlated with IQs at younger ages, and IQ improved with age for infants exposed to any antiepileptic drug. Compared with a normative sample (173 93% of 187 children), right-handedness was less frequent in children in our study overall (185 86% of 215; p=0·0404) and in the lamotrigine (59 83% of 71; p=0·0287) and valproate (38 79% of 40; p=0·0089) groups. Verbal abilities were worse than non-verbal abilities in children in our study overall and in the lamotrigine and valproate groups. Mean IQs were higher in children exposed to periconceptional folate (108, 95% CI 106–111) than they were in unexposed children (101, 98–104; p=0·0009). Interpretation Fetal valproate exposure has dose-dependent associations with reduced cognitive abilities across a range of domains at 6 years of age. Reduced right-handedness and verbal ( vs non-verbal) abilities might be attributable to changes in cerebral lateralisation induced by exposure to antiepileptic drugs. The positive association of periconceptional folate with IQ is consistent with other recent studies. Funding US National Institutes of Health, UK Epilepsy Research Foundation.
Most children born to women with epilepsy (WWE) are normal, but have increased risks for malformations and poor neuropsychological outcomes. Antiseizure medications (ASMs) are among the most commonly ...prescribed teratogenic medications in women of childbearing age. However, WWE typically cannot avoid using ASMs during pregnancy. Teratogenic risks vary across ASMs. Valproate poses a special risk for anatomic and behavioral teratogenic risks compared with other ASMs. The risks for many ASMs remain uncertain. Women of childbearing potential taking ASMs should be taking folic acid. Breastfeeding while taking ASMs seems safe. WWE should receive informed consent outlining risks before conception.
Marked changes in US medical school funding began in the 1960s with progressively increasing revenues from clinical services. The growth of clinical revenues slowed in the mid-1990s, creating a ...funding crisis for US academic health care centers, who responded by having their faculty increase their clinical duties at the expense of research activities. Surveys document the resultant stresses on the academic clinician researcher. The NIH provides greater funding for basic and translational research than for clinical research, and the new Patient-Centered Outcomes Research Institute is inadequately funded to address the scope of needed clinical research. An increasing portion of clinical research is funded by industry, which leaves many important clinical issues unaddressed. There is an inadequate supply of skilled clinical researchers and a lack of external support for clinical research. The impact on the academic environment in university medical centers is especially severe on young faculty, who have a shrinking potential to achieve successful academic careers. National health care research funding policies should encourage the right balance of life-science investigations. Medical universities need to improve and highlight education on clinical research for students, residents, fellows, and young faculty. Medical universities also need to provide appropriate incentives for clinical research. Without training to ensure an adequate supply of skilled clinical researchers and a method to adequately fund clinical research, discoveries from basic and translational research cannot be clinically tested and affect patient care. Thus, many clinical problems will continue to be evaluated and treated with inadequate or even absent evidence-based knowledge.
This scientific commentary refers to ‘Integrative genomics reveals pathogenic mediator of valproate-induced neurodevelopmental disability’ by Feleke et al. (https://doi.org/10.1093/brain/awac296).
Summary
Objective
Responsive neurostimulation decreases the frequency of disabling seizures when used as an adjunctive therapy in patients with medically refractory partial‐onset seizures. The effect ...of long‐term responsive neurostimulation on neuropsychological performance has not yet been established.
Methods
Neuropsychological data were collected from subjects participating in the open‐label arm of a randomized controlled trial of responsive neurostimulation with the RNS® System. Primary cognitive outcomes were the Boston Naming Test (BNT) and Rey Auditory Verbal Learning (AVLT) test. Neuropsychological performance was evaluated at baseline and again following 1 and 2 years of RNS System treatment. Follow‐up analyses were conducted in patients with seizure onset restricted to either the mesial temporal lobe or neocortex.
Results
No significant cognitive declines were observed for any neuropsychological measure through 2 years. When examined as a function of seizure onset region, a double dissociation was found, with significant improvement in naming across all patients (p < 0.0001), and for patients with neocortical seizure onsets (p < 0.0001) but not in patients with mesial temporal lobe (MTL) seizure onsets (p = 0.679). In contrast, a significant improvement in verbal learning was observed across all patients (p = 0.03), and for patients with MTL seizure onsets (p = 0.005) but not for patients with neocortical onsets (p = 0.403).
Significance
Treatment with the RNS System is not associated with cognitive decline when tested through 2 years. In fact, there were small but significant beneficial treatment effects on naming in patients with neocortical onsets and modest improvements in verbal learning for patients with seizure onsets in MTL structures. These results suggest that there are modest cognitive improvements in some domains that vary as a function of the region from which seizures arise.
Increasing evidence suggests that exposure to certain antiepileptic drugs (AEDs) during critical periods of development may induce transient or long-lasting neurodevelopmental deficits across ...cognitive, motor and behavioral domains. The developing nervous system may endure prolonged chronic exposure to AEDs during pregnancy (in utero) or during childhood, which can lead to neurodevelopmental defects such as congenital neural tube defects, lower IQ, language deficits, autism and ADHD. To date, valproate is the most widely recognized AED to significantly negatively affect neurodevelopment, and demonstrates greater adverse effects than any other AEDs that have been assessed. Although some AEDs appear to have low risk (i.e., lamotrigine, levetiracetam), other AEDs have been implicated in a variety of studies detailed below, and many AEDs have not been adequately assessed. The purpose of this review article is to summarize our current understanding of the neurodevelopmental effects of AEDs.
Antiepileptic drugs (AEDs) are among the most common teratogenic drugs prescribed to women of childbearing age. AEDs can induce both anatomical (malformations) and behavioral (cognitive/behavioral ...deficits) teratogenicity. Only in the last decade have we begun to truly discriminate differential AED developmental effects. Fetal valproate exposure carries a special risk for both anatomical and behavioral teratogenic abnormalities, but the mechanisms and reasons for individual variability are unknown. Intermediate anatomical risks exist for phenobarbital and topiramate. Several AEDs (e.g., lamotrigine and levetiracetam) appear to possess low risks for both anatomical and behavioral teratogenesis. Despite advances in the past decade, our knowledge of the teratogenic risks for most AEDs and the underlying mechanisms remain inadequate. Further, the long-term effects of AEDs in neonates and older children remain uncertain. The pace of progress is slow given the lifelong consequences of diminished developmental outcomes, exposing children unnecessarily to potential adverse effects. It is imperative that new approaches be employed to determine risks more expediently. Our recommendations include a national reporting system for congenital malformations, federal funding of the North American AED Pregnancy Registry, routine meta-analyses of cohort studies to detect teratogenic signals, monitoring of AED prescription practices for women, routine preclinical testing of all new AEDs for neurodevelopmental effects, more specific Food and Drug Administration requirements to establish differential AED cognitive effects in children, and improved funding of basic and clinical research to fully delineate risks and underlying mechanisms for AED-induced anatomical and behavioral teratogenesis.
The study aims were to investigate secular trends in antiepileptic drug (AED) use in women during pregnancy, and to compare the use of first- and second-generation AEDs.
Study participants consisted ...of female Florida Medicaid beneficiaries, older than 15 years, and pregnant within the time period 1999 to 2009. Fifteen AEDs were categorized into first and second generation of AEDs. Continuous use of AEDs was defined as at least 2 consecutive AED prescriptions totaling more than a 30-day supply. Polytherapy was defined as 2 or more AEDs continuously used for at least 30 overlapping days. Annual prevalence was estimated and compared.
We included 2,099 pregnant women who were enrolled in Florida Medicaid from 1999 to 2009 and exposed to AEDs during pregnancy. Although there were fluctuations, overall AED use in the study cohort did not increase from 2000 to 2009 (β ± standard error SE: -0.07 ± 0.06, p = 0.31). The use of first-generation AEDs decreased (β ± SE: -6.21 ± 0.47, p < 0.0001), whereas the use of second-generation AEDs increased (β ± SE: 6.27 ± 0.52, p < 0.0001) from 2000 to 2009. AED use in polytherapy did not change through the study period. Valproate use reduced from 23% to 8% in the study population (β ± SE: -1.61 ± 0.36, p = 0.0019), but this decrease was only for women receiving an AED for epilepsy and was not present for other indications.
The second-generation AEDs are replacing first-generation AEDs in both monotherapy and polytherapy. Valproate use has declined for epilepsy but not other indications. Additional changes in AED use are expected in future years.