Evidence for spared attention to faces in 7-month-old infants after prenatal exposure to antiepileptic drugs

Neurodevelopmental and Functional Outcomes Following In Utero Exposure to Antiseizure Medication: A Systematic Review

BACKGROUND AND OBJECTIVES

To undertake a systematic review of the available literature to examine the relationship between prenatal antiseizure medication (ASM) exposure and adverse postnatal neurodevelopmental outcomes, focusing on social, emotional, behavioral, and adaptive domains of human function, and the frequency of neurodevelopmental and psychiatric disorders in ASM-exposed offspring.

METHODS

Electronic searches of MEDLINE, PsychINFO, and EMBASE were conducted and limited to studies published between 1990 and 2023 in English. Studies were eligible if they prospectively or retrospectively reported neurodevelopmental outcomes of ASM-exposed offspring. The Newcastle-Ottawa scale was used to conduct methodologic quality assessments of included studies, and a narrative synthesis integrated the review findings.

RESULTS

Forty-three studies were included. Valproate has been consistently associated with a 2- to 4-fold increased risk of autism spectrum disorder (ASD), 2- to 5-fold increased risk of intellectual disability (ID), and poor adaptive functioning. Growing evidence indicates that topiramate is associated with a 2-fold increased risk of ASD and 3- to 4-fold increased risk of ID. The risks of adverse neurodevelopmental outcomes for valproate and topiramate seem to be dose dependent. Phenobarbital has been suggested to be associated with deleterious neurodevelopmental effects, but data are limited. Levetiracetam has recently been linked with an increased risk of attention deficit hyperactivity disorder and anxiety disorders in a single study. Carbamazepine has been associated with variable neurodevelopmental outcomes. Lamotrigine seems to be "safe" in terms of postnatal neurodevelopment. Data for oxcarbazepine, phenytoin, and clonazepam are limited but seem to have little-to-no risk of adverse outcomes. Evidence for the remaining ASMs, including gabapentin, pregabalin, lacosamide, zonisamide, clobazam, perampanel, ethosuximide, or brivaracetam, is lacking. Several methodologic limitations impeded data synthesis, including heterogeneity in outcome measures and small samples of monotherapy exposures.

DISCUSSION

The findings of this review support the conclusion that valproate and topiramate use during pregnancy is associated with a significantly increased risk of neurodevelopmental effects on the fetus. Apart from lamotrigine, which seems to be free of adverse neurodevelopmental effects, data for the other ASMs are mixed or inadequate to draw definite conclusions. Further research into the neurodevelopmental effects of prenatal exposure to ASMs, including most newer agents, is much needed.

Neurodevelopmental outcomes after prenatal exposure to lamotrigine monotherapy in women with epilepsy: a systematic review and meta-analysis

BACKGROUND

Lamotrigine has become one of the most commonly prescribed antiseizure medications (ASM) in epileptic women during pregnancy and therefore requires regular updates regarding its safety. The aim of this study was to estimate the association between in utero exposure to lamotrigine monotherapy and the occurrence of neurodevelopmental outcomes.

METHODS

All comparative studies assessing the occurrence of neurodevelopmental outcomes after epilepsy-indicated lamotrigine monotherapy exposure during pregnancy were searched. First, references were identified through a snowballing approach, then, through electronic databases (Medline and Embase) from 2015 to June 2022. One investigator evaluated study eligibility and extracted data and a second independent investigator reviewed the meta-analysis (MA). A systematic review and random-effects model approach were performed using a collaborative WEB-based meta-analysis platform (metaPreg.org) with a registered protocol (osf.io/u4gva).

RESULTS

Overall, 18 studies were included. For outcomes reported by at least 4 studies, the pooled odds ratios and 95% confidence interval obtained with the number of exposed (N1) and unexposed children (N0) included were: neurodevelopmental disorders as a whole 0.84 [0.66;1.06] (N1 = 5,271; N0 = 22,230); language disorders or delay 1.16 [0.67;2.00] (N1 = 313; N0 = 506); diagnosis or risk of ASD 0.97 [0.61;1.53] (N1 = at least 5,262; N0 = 33,313); diagnosis or risk of ADHD 1.14 [0.75;1.72] (N1 = at least 113; N0 = 11,530) and psychomotor developmental disorders or delay 2.68 [1.29-5.56] (N1 = 163; N0 = 220). The MA of cognitive outcomes included less than 4 studies and retrieved a significant association for infants exposed to lamotrigine younger than 3 years old but not in the older age groups.

CONCLUSION

Prenatal exposure to lamotrigine monotherapy is not found to be statistically associated with neurodevelopmental disorders as a whole, language disorders or delay, diagnosis or risk of ASD and diagnosis or risk of ADHD. However, the MA found an increased risk of psychomotor developmental disorders or delay and cognitive developmental delay in less than 3 years old children. Nevertheless, these findings were based exclusively on observational studies presenting biases and on a limited number of included children. More studies should assess neurodevelopmental outcomes in children prenatally exposed to lamotrigine.

Adverse Fetal and Neonatal Outcomes following in-utero exposure to Oxcarbazepine: A Systematic Review and Meta-Analysis

AIM

This systematic review aims to assess the safety profile of oxcarbazepine during pregnancy.

METHODS

Observational studies that included women who took oxcarbazepine anytime during pregnancy were included in our systematic review. The review did not include non-English articles, reviews, meta-analyses, case reports, and animal studies. Different online sources such as MEDLINE, Cochrane library, Virtual Health Library, etc. were searched for published and unpublished literature. Assessment of the risk of bias in observational studies was done using the Newcastle-Ottawa Scale. The meta-analyses were performed using a random-effect model. GRADE was used for the evaluation of the quality of evidence for the primary outcomes.

RESULTS

We included 19 cohort studies with a total number of 5,071,137 patients, of which 2,450 were exposed to oxcarbazepine either as monotherapy or polytherapy. The summary odds ratio (OR) was 1.69 (95% CI, 0.95-2.98) for congenital malformations following in-utero exposure to oxcarbazepine as compared to the control group of unexposed patients [seven studies (n=625)], and was 1.19 (95% CI, 0.67-2.12) when compared to those following lamotrigine (LTG) exposure during pregnancy [3 studies (n=591)]. In total, three studies (n=770) reported the association between in-utero oxcarbazepine exposure and fetal/perinatal deaths. The meta-analysis yielded a summary OR of 3.33 (95% CI, 1.70-6.51).

SIGNIFICANCE

Our systematic review will help healthcare providers and guideline developers regarding the treatment of epilepsy and other neurological disorders during pregnancy. More cohort studies with a higher sample size concerning oxcarbazepine use in pregnant patients are required to truly assess the in-utero safety profile of the drug.

Neurodevelopmental outcomes in children exposed prenatally to levetiracetam

Some old antiseizure medications (ASMs) pose teratogenic risks, including major congenital malformations and neurodevelopmental delay. Therefore, the use of new ASMs in pregnancy is increasing, particularly lamotrigine and levetiracetam. This is likely due to evidence of low risk of anatomical teratogenicity for both lamotrigine and levetiracetam. Regarding neurodevelopmental effects, lamotrigine is the most frequently investigated new ASM with information available for children up to 14 years of age. However, fewer data are available for the effects of levetiracetam on cognitive and behavioral development, with smaller cohorts and shorter follow-up. The aim of the present review was to explicate neurodevelopmental outcomes in children exposed prenatally to levetiracetam to support clinical decision-making. The available data do not indicate an increased risk of abnormal neurodevelopmental outcomes in children exposed prenatally to levetiracetam. Findings demonstrated comparable outcomes for levetiracetam versus controls and favorable outcomes for levetiracetam versus valproate on global and specific cognitive abilities, and behavioral problems. In addition, the available evidence shows no significant dose-effect association for levetiracetam on neurodevelopmental outcomes. However, this evidence cannot be determined definitively due to the limited numbers of exposures with relatively short follow-up. Therefore, further research is required.

Impact of In Utero Exposure to Antiepileptic Drugs on Neonatal Brain Function

In utero brain development underpins brain health across the lifespan but is vulnerable to physiological and pharmacological perturbation. Here, we show that antiepileptic medication during pregnancy impacts on cortical activity during neonatal sleep, a potent indicator of newborn brain health. These effects are evident in frequency-specific functional brain networks and carry prognostic information for later neurodevelopment. Notably, such effects differ between different antiepileptic drugs that suggest neurodevelopmental adversity from exposure to antiepileptic drugs and not maternal epilepsy per se. This work provides translatable bedside metrics of brain health that are sensitive to the effects of antiepileptic drugs on postnatal neurodevelopment and carry direct prognostic value.

Neurodevelopmental outcomes in children exposed to newer antiseizure medications: A systematic review

As prenatal exposure to certain older antiseizure medications (ASMs) has been linked with poorer neurodevelopmental outcomes in children, the use of newer ASMs throughout pregnancy has increased. The current review aimed to delineate the impact of in utero exposure to these newer ASMs on child neurodevelopment. A systematic search of MEDLINE, Embase, Web of Science, Cumulative Index to Nursing and Allied Health Literature Plus, and PsycINFO was conducted, limiting results to articles available in English and published after the year 2000. Studies investigating neurodevelopmental outcomes following in utero exposure to the following ASMs were eligible for inclusion in the review: eslicarbazepine, gabapentin, lacosamide, lamotrigine, levetiracetam, oxcarbazepine, perampanel, topiramate, and zonisamide. Thirty-five publications were identified, and a narrative synthesis was undertaken. Methodological quality was variable, with distinct patterns of strengths/weaknesses attributable to design. Most studies examined lamotrigine exposure and reported nonsignificant effects on child neurodevelopment. Comparatively fewer high-quality studies were available for levetiracetam, limiting conclusions regarding findings to date. Data for topiramate, gabapentin, and oxcarbazepine were so limited that firm conclusions could not be drawn. Concerningly, no studies investigated eslicarbazepine, lacosamide, perampanel, or zonisamide. Exposure to certain newer ASMs, such as lamotrigine and levetiracetam, does not thus far appear to impact certain aspects of neurodevelopment, but further delineation across the different neurodevelopmental domains and dosage levels is required. A lack of data cannot be inferred to represent safety of newer ASMs, which are yet to be investigated.

The long-term prognosis of hippocampal neurogenesis and behavioral changes of offspring from rats exposed to valproic acid during pregnancy

Aim

In pregnant women with epilepsy, it is essential to balance maternal safety and the potential teratogenicity of anticonvulsants. Recently, growing evidence has indicated that valproic acid (VPA) can produce postnatal congenital malformations and impair cognitive function. However, the mechanisms underlying cognitive dysfunction in long‐term prognoses remain unclear.

Methods

Pregnant Wistar rats received daily intraperitoneal injections of VPA (200 mg/kg/day) from embryonic day 12.5 until birth. On postnatal day (PD) 149, the rats received an injection of bromodeoxyuridine (BrdU). On PD 150, the rats were subjected to the open field (OF), elevated plus‐maze (EPM), and Y‐maze tests. After behavioral testing, perfusion fixation was performed and the brain was dissected for immunohistochemistry.

Results

A significant marked decrease was seen in the number of BrdU‐positive cells in the dentate gyrus of offspring of VPA‐treated dams compared to those of control. However, no significant differences in hyperactivity were found based on the results of the OF test among the offspring on PD 150 of 200 VPA‐treated dams. In addition, no significant differences were seen in the EPM test.

Conclusion

The behavioral abnormality observed in young offspring of VPA‐treated dams was not significantly different from that of controls in adult offspring on PD 150. However, compared with controls, the number of BrdU‐positive cells in VPA‐treated rats was halved. The findings suggest that the behavioral abnormality seems to improve as they grow, even if some structural abnormalities may remain in the central nervous system.

Pregnant Wistar rats received daily intraperitoneal injections of VPA (200 mg/kg/d) from embryonic day 12.5 until birth. On postnatal day (PD) 149, the rats received an injection of bromodeoxyuridine (BrdU). A significant marked decrease was seen in the number of BrdU‐positive cells in the dentate gyrus of offspring of VPA‐treated dams compared to those of control.

Newborn left amygdala volume associates with attention disengagement from fearful faces at eight months

After 5 months of age, infants begin to prioritize attention to fearful over other facial expressions. One key proposition is that amygdala and related early-maturing subcortical network, is important for emergence of this attentional bias - however, empirical data to support these assertions are lacking. In this prospective longitudinal study, we measured amygdala volumes from MR images in 65 healthy neonates at 2-5 weeks of gestation corrected age and attention disengagement from fearful vs. non-fearful facial expressions at 8 months with eye tracking. Overall, infants were less likely to disengage from fearful than happy/neutral faces, demonstrating an age-typical bias for fear. Left, but not right, amygdala volume (corrected for intracranial volume) was positively associated with the likelihood of disengaging attention from fearful faces to a salient lateral distractor (r = .302, p = .014). No association was observed with the disengagement from neutral or happy faces in equivalent conditions (r = .166 and .125, p = .186 and .320, respectively). These results are the first to link the amygdala volume with the emerging perceptual vigilance for fearful faces during infancy. They suggest a link from the prenatally defined variability in the amygdala size to early postnatal emotional and social traits.

Advances in Epidemiological Methods and Utilisation of Large Databases: A Methodological Review of Observational Studies on Central Nervous System Drug Use in Pregnancy and Central Nervous System Outcomes in Children

INTRODUCTION

Studies have used various epidemiological approaches to study associations between central nervous system (CNS) drug use in pregnancy and CNS outcomes in children. Studies have generally focused on clinical adverse effects, whereas variations in methodologies have not received sufficient attention.

OBJECTIVE

Our objective was to review the methodological characteristics of existing studies to identify any limitations and recommend further research.

METHODS

A systematic literature search was conducted on observational studies listed in PubMed from 1 January 1946 to 21 September 2017. Following independent screening and data extraction, we conducted a review addressing the trends of relevant studies, differences between various data sources, and methods used to address bias and confounders; we also conducted statistical analyses.

RESULTS

In total, 111 observational studies, 25 case-control studies, and 86 cohort studies were included in the review. Publications dating from 1978 to 2006 mainly focused on antiepileptic drugs, but research on antidepressants increased from 2007 onwards. Only one study focused on antipsychotic use during pregnancy. A total of 46 studies obtained data from an administrative database/registry, 20 from ad hoc disease registries, and 41 from ad hoc clinical samples. Most studies (58%) adjusted the confounding factors using general adjustment, whereas only a few studies used advanced methods such as sibling-matched models and propensity score methods; 42 articles used univariate analyses and 69 conducted multivariable regression analyses.

CONCLUSION

Multiple factors, including different study designs and data sources, have led to inconsistent findings in associations between CNS drug use in pregnancy and CNS outcomes in children. Researchers should allow for study designs with clearly defined exposure periods, at the very least in trimesters, and use advanced confounding adjustment methodology to increase the accuracy of the findings.

Prenatal exposure to antiepileptic drugs and early processing of emotionally relevant sounds

INTRODUCTION

Prenatal exposure to antiepileptic drugs (AEDs) is associated with developmental compromises in verbal intelligence and social skills in childhood. Our aim was to evaluate whether a multifeature Mismatch Negativity (MMN) paradigm assessing semantic and emotional components of linguistic and emotional processing would be useful to detect possible alterations in early auditory processing of newborns with prenatal AED exposure.

MATERIAL AND METHODS

Data on AED exposure, pregnancy outcome, neuropsychological evaluation of the mothers, information on maternal epilepsy type, and a structured neurological examination of the newborn were collected prospectively. Blinded to AED exposure, we compared a cohort of 36 AED-exposed with 46 control newborns at the age of two weeks by measuring MMN with a multifeature paradigm with six linguistically relevant deviant sounds and three emotionally uttered sounds.

RESULTS

Frontal responses for the emotionally uttered stimulus Happy differed significantly in the exposed newborns compared with the control newborns. In addition, responses to sounds with or without emotional component differed in newborns exposed to multiple AEDs compared with control newborns or to newborns exposed to only one AED.

CONCLUSIONS

These preliminary findings suggest that prenatal AED exposure may alter early processing of emotionally and linguistically relevant sound information.

Prenatal exposure to valproic acid is associated with altered neurocognitive function and neurogenesis in the dentate gyrus of male offspring rats

In pregnant women with epilepsy, it is imperative to balance the safety of the mother and the potential teratogenicity of anticonvulsants, which could cause impairments such as intellectual disability and cleft lip. In this study, we examined behavioral and hippocampal neurogenesis alterations in male offspring of rats exposed to valproic acid (VPA) during pregnancy. Pregnant Wistar rats received daily intraperitoneal injections of VPA (100 mg/kg/day or 200 mg/kg/day) from embryonic day 12.5 until birth. At postnatal day 29, animals received an injection of bromodeoxyuridine (BrdU). At postnatal day 30, animals underwent the open field (OF), elevated plus-maze, and Y-maze tests. After behavioral testing, animals were decapitated, and their brains were dissected for immunohistochemistry. Of the offspring of the VPA200 mothers, 66.6% showed a malformation. In the OF test, these animals showed locomotor hyperactivity. In the elevated plus-maze, offspring of VPA-treated mothers spent significantly more time in the open arms, irrespective of the treatment dose. The number of BrdU-positive cells in the dentate gyrus of the offspring of VPA-treated mothers increased significantly in a dose-dependent manner compared with the control. A significant positive correlation between spontaneous locomotor activity in the OF and BrdU-positive cell counts was observed across groups. In conclusion, VPA administration during pregnancy results in malformations and attention-deficit/hyperactivity disorder-like behavioral abnormalities in the offspring. An increase in cell proliferation in the hippocampus may underlie the behavioral changes observed. Repeated use of high doses of VPA during pregnancy may increase the risk of neurodevelopmental abnormalities dose dependently and should be carefully considered.

Retrospective Analysis of Oxcarbazepine in Pregnant Women With Substance Use Disorders: Focus on Safety

BACKGROUND

Published safety data in pregnant epileptic women suggests that oxcarbazepine (OXC) may be a treatment option in nonepileptic pregnant women with substance use disorders (SUDs) and psychiatric symptomatology.

OBJECTIVE

To compare safety outcomes associated with OXC exposure versus non-exposure in nonepileptic pregnant women with SUD and comorbid psychiatric symptomatology.

METHODS

A retrospective chart review was conducted to identify pregnant women 18 years or older with a SUD who delivered at the study site. Exclusion criteria included a current diagnosis of epilepsy/seizure disorder; concurrent use of lithium, anticonvulsants, medications with a Risk Evaluation and Mitigation Strategy program or a black box warning for potential fetal toxicity; and multi-parity. Eligible patients were divided into two groups based on OXC exposure.

RESULTS

The OXC group included 94 mother-neonate pairs versus 194 mother-neonate pairs in the non-OXC group. Baseline characteristics differed in mean number of prior pregnancies (2.8 vs 2.2 in the OXC and non-OXC group, respectively, P = .03). No significant differences were found regarding emergent cesarean or maternal hyponatremia. Average gestational age at OXC initiation was 19.8 weeks. No significant differences were found in the rates of prematurity, physical characteristics, malformation, and neonatal abstinence syndrome.

CONCLUSION

OXC may be considered for management of SUD with comorbid psychiatric symptomatology in nonepileptic pregnant women. Further studies should be conducted to determine statistical significance in larger sample sizes.

In Utero Oxcarbazepine Exposure and Neonatal Abstinence Syndrome: Case Report and Brief Review of the Literature

Oxcarbazepine is a second‐generation antiepileptic drug that is used to treat partial seizures. Although it has been increasingly used in pregnant women, its fetal safety has not been fully validated. We describe a 12‐hour‐old neonate who developed neonatal abstinence syndrome (NAS) after intrauterine exposure to oxcarbazepine. The neonate was born via cesarean section to a mother who took oxcarbazepine 300 mg/day for treatment of seizures throughout her pregnancy. Approximately 12 hours after birth, the infant developed paroxysmal jitter, which mainly presented as increased excitability, irritability, limb shaking, and increased muscle tone. These symptoms resolved by day 9 of life. Although NAS occurs most often after in utero exposure to opioids, exposure to other drugs during pregnancy may contribute to a small proportion of NAS cases. To our knowledge, this is the second case report of oxcarbazepine‐induced NAS. Pregnant women with epilepsy should weigh the pros and cons of continuing oxcarbazepine during their pregnancy when they are prescribed this drug. For infants with in utero oxcarbazepine exposure, comprehensive assessments and examinations are necessary for screening oxcarbazepine‐induced NAS.

Neurodevelopmental Effects of Antiepileptic Drugs

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.