Long term health and neurodevelopment in children exposed to antiepileptic drugs before birth

Adolescent treadmill exercise enhances hippocampal brain-derived neurotrophic factor (BDNF) expression and improves cognition in autism-modeled rats

Autism spectrum disorder (ASD) is a prevalent neurodevelopmental disorder characterized by repetitive behaviors and altered communication abilities. Exercise is a low-cost intervention that could improve cognitive function and improve brain plasticity mechanisms. Here, the valproic acid (VPA) model was utilized to induce ASD-like phenotypes in rodents. Animals were exercised on a treadmill and performance was evaluated on a cognitive flexibility task. Biomarkers related to exercise and plasticity regulation were quantified from the prefrontal cortex, hippocampus, and skeletal muscle. Exercised VPA animals had higher levels of hippocampal BDNF compared to sedentary VPA animals and upregulated antioxidant enzyme expression in skeletal muscle. Cognitive improvements were demonstrated in both sexes, but in different domains of cognitive flexibility. This research demonstrates the benefits of exercise and provides evidence that molecular responses to exercise occur in both the central nervous system and in the periphery. These results suggest that improving regulation of BDNF via exercise, even at low intensity, could provide better synaptic regulation and cognitive benefits for individuals with ASD.

Therapeutic effects of nanosilibinin in valproic acid-zebrafish model of autism spectrum disorder: Focusing on Wnt signaling pathway and autism spectrum disorder-related cytokines

In this study, we delved into the intricate world of autism spectrum disorder (ASD) and its connection to the disturbance in the Wnt signaling pathway and immunological abnormalities. Our aim was to evaluate the impact of silibinin, a remarkable modulator of both the Wnt signaling pathway and the immune system, on the neurobehavioral and molecular patterns observed in a zebrafish model of ASD induced by valproic acid (VPA). Because silibinin is a hydrophobic molecule and highly insoluble in water, it was used in the form of silibinin nanoparticles (nanosilibinin, NS). After assessing survival, hatching rate, and morphology of zebrafish larvae exposed to different concentrations of NS, the appropriate concentrations were chosen. Then, zebrafish embryos were exposed to VPA (1 μM) and NS (100 and 200 μM) at the same time for 120 h. Next, anxiety and inattentive behaviors and the expression of CHD8, CTNNB, GSK3beta, LRP6, TNFalpha, IL1beta, and BDNF genes were assessed 7 days post fertilization. The results indicated that higher concentrations of NS had adverse effects on survival, hatching, and morphological development. The concentrations of 100 and 200 μM of NS could ameliorate the anxiety-like behavior and learning deficit and decrease ASD-related cytokines (IL1beta and TNFalpha) in VPA-treated larvae. In addition, only 100 μM of NS prevented raising the gene expression of Wnt signaling-related factors (CHD8, CTNNB, GSK3beta, and LRP6). In conclusion, NS treatment for the first 120 h showed therapeutic effect on an autism-like phenotype probably via reducing the expression of pro-inflammatory cytokines genes and changing the expression of Wnt signaling components genes.

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.

Risk of Autism after Prenatal Topiramate, Valproate, or Lamotrigine Exposure

BACKGROUND

Maternal use of valproate during pregnancy has been associated with an increased risk of neurodevelopmental disorders in children. Although most studies of other antiseizure medications have not shown increased risks of these disorders, there are limited and conflicting data regarding the risk of autism spectrum disorder associated with maternal topiramate use.

METHODS

We identified a population-based cohort of pregnant women and their children within two health care utilization databases in the United States, with data from 2000 through 2020. Exposure to specific antiseizure medications was defined on the basis of prescription fills from gestational week 19 until delivery. Children who had been exposed to topiramate during the second half of pregnancy were compared with those unexposed to any antiseizure medication during pregnancy with respect to the risk of autism spectrum disorder. Valproate was used as a positive control, and lamotrigine was used as a negative control.

RESULTS

The estimated cumulative incidence of autism spectrum disorder at 8 years of age was 1.9% for the full population of children who had not been exposed to antiseizure medication (4,199,796 children). With restriction to children born to mothers with epilepsy, the incidence was 4.2% with no exposure to antiseizure medication (8815 children), 6.2% with exposure to topiramate (1030 children), 10.5% with exposure to valproate (800 children), and 4.1% with exposure to lamotrigine (4205 children). Propensity score-adjusted hazard ratios in a comparison with no exposure to antiseizure medication were 0.96 (95% confidence interval [CI], 0.56 to 1.65) for exposure to topiramate, 2.67 (95% CI, 1.69 to 4.20) for exposure to valproate, and 1.00 (95% CI, 0.69 to 1.46) for exposure to lamotrigine.

CONCLUSIONS

The incidence of autism spectrum disorder was higher among children prenatally exposed to the studied antiseizure medications than in the general population. However, after adjustment for indication and other confounders, the association was substantially attenuated for topiramate and lamotrigine, whereas an increased risk remained for valproate. (Funded by the National Institute of Mental Health.).

Three Decades of Valproate: A Current Model for Studying Autism Spectrum Disorder

Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder with increased prevalence and incidence in recent decades. Its etiology remains largely unclear, but it seems to involve a strong genetic component and environmental factors that, in turn, induce epigenetic changes during embryonic and postnatal brain development. In recent decades, clinical studies have shown that inutero exposure to valproic acid (VPA), a commonly prescribed antiepileptic drug, is an environmental factor associated with an increased risk of ASD. Subsequently, prenatal VPA exposure in rodents has been established as a reliable translational model to study the pathophysiology of ASD, which has helped demonstrate neurobiological changes in rodents, non-human primates, and brain organoids from human pluripotent stem cells. This evidence supports the notion that prenatal VPA exposure is a valid and current model to replicate an idiopathic ASD-like disorder in experimental animals. This review summarizes and describes the current features reported with this animal model of autism and the main neurobiological findings and correlates that help elucidate the pathophysiology of ASD. Finally, we discuss the general framework of the VPA model in comparison to other environmental and genetic ASD models.

Valproic Acid in Pregnancy Revisited: Neurobehavioral, Biochemical and Molecular Changes Affecting the Embryo and Fetus in Humans and in Animals: A Narrative Review

Valproic acid (VPA) is a very effective anticonvulsant and mood stabilizer with relatively few side effects. Being an epigenetic modulator, it undergoes clinical trials for the treatment of advanced prostatic and breast cancer. However, in pregnancy, it seems to be the most teratogenic antiepileptic drug. Among the proven effects are congenital malformations in about 10%. The more common congenital malformations are neural tube defects, cardiac anomalies, urogenital malformations including hypospadias, skeletal malformations and orofacial clefts. These effects are dose related; daily doses below 600 mg have a limited teratogenic potential. VPA, when added to other anti-seizure medications, increases the malformations rate. It induces malformations even when taken for indications other than epilepsy, adding to the data that epilepsy is not responsible for the teratogenic effects. VPA increases the rate of neurodevelopmental problems causing reduced cognitive abilities and language impairment. It also increases the prevalence of specific neurodevelopmental syndromes like autism (ASD) and Attention Deficit Hyperactivity Disorder (ADHD). High doses of folic acid administered prior to and during pregnancy might alleviate some of the teratogenic effect of VPA and other AEDs. Several teratogenic mechanisms are proposed for VPA, but the most important mechanisms seem to be its effects on the metabolism of folate, SAMe and histones, thus affecting DNA methylation. VPA crosses the human placenta and was found at higher concentrations in fetal blood. Its concentrations in milk are low, therefore nursing is permitted. Animal studies generally recapitulate human data.

Neurodevelopmental outcomes in children and adults with Fetal Valproate Spectrum Disorder: A contribution from the ConcePTION project

AIM

To describe the neurodevelopmental phenotype of older children and adults with a diagnosis of Fetal Valproate Spectrum Disorder (FVSD).

METHODS

In this cross-sectional study, 90 caregivers were recruited and completed a series of questionnaires regarding the neurodevelopmental outcomes of 146 individuals aged 7-37 years (M = 18.1), including individuals with a formal diagnosis of FVSD (n = 99), individuals exposed to Valproate but without an FVSD diagnosis (n = 24), and individuals not exposed to Valproate (N = 23). The mean dose of valproate exposure for individuals with an FVSD diagnosis was 1470 mg/day.

RESULTS

Individuals with a diagnosis of FVSD showed significantly higher levels of moderate (43.4%) and severe (14.4%) cognitive impairment than other groups (p = 0.003), high levels of required formal educational support (77.6%), and poorer academic competence than individuals not exposed to Valproate (p = 0.001). Overall psychosocial problems (p = 0.02), internalising problems (p = 0.05) and attention problems (p = 0.001), but not externalising problems, were elevated in individuals with a diagnosis of FVSD. Rates of neurodevelopmental disorders, particularly autistic spectrum disorders (62.9%) and sensory problems (80.6%) are particularly central to the FVSD phenotype. There was no evidence of a statistical dose-dependent effect, possibly due to the high mean dose of exposure having a uniformly negative impact across the sample. Individuals with FVSD had required a significant number of health and child development services.

INTERPRETATION

Children and young adults with a diagnosis of FVSD are at an increased risk of a range of altered neurodevelopmental outcomes, highlighting the need for a multidisciplinary approach to clinical management across the lifespan.

Alterations of Purinergic Receptors Levels and Their Involvement in the Glial Cell Morphology in a Pre-Clinical Model of Autism Spectrum Disorders

Recent data suggest that defects in purinergic signalling are a common denominator of autism spectrum disorders (ASDs), though nothing is known about whether the disorder-related imbalance occurs at the receptor level. In this study, we investigated whether prenatal exposure to valproic acid (VPA) induces changes in purinergic receptor expression in adolescence and whether it corresponds to glial cell activation. Pregnant dams were subjected to an intraperitoneal injection of VPA at embryonic day 12.5. In the hippocampi of adolescent male VPA offspring, we observed an increase in the level of P2X1, with concomitant decreases in P2X7 and P2Y1 receptors. In contrast, in the cortex, the level of P2X1 was significantly reduced. Also, significant increases in cortical P2Y1 and P2Y12 receptors were detected. Additionally, we observed profound alterations in microglial cell numbers and morphology in the cortex of VPA animals, leading to the elevation of pro-inflammatory cytokine expression. The changes in glial cells were partially reduced via a single administration of a non-selective P2 receptor antagonist. These studies show the involvement of purinergic signalling imbalance in the modulation of brain inflammatory response induced via prenatal VPA exposure and may indicate that purinergic receptors are a novel target for pharmacological intervention in ASDs.

Adolescent female valproic acid rats have impaired extra-dimensional shifts of attention and enlarged anterior cingulate cortices

In order to develop better treatments for autism spectrum disorder (ASD) it is critical to understand the developmental trajectory of the disorder and the accompanying brain changes. This study used the valproic acid (VPA) model to induce ASD-like symptoms in rodents. Prior studies have demonstrated that VPA animals are impaired on executive function tasks, paralleling results in humans with ASD. Here, VPA adolescent female rats were impaired on a set-shifting task and had enlarged frontal cortices compared to control females. The deficits observed in the VPA female rats mirrors results in females with ASD. In addition, adolescent VPA females with enlarged frontal cortices performed the worst across the entire task. These brain changes in adolescence are also found in adolescent humans with ASD. These novel findings highlight the importance of studying the brain at different developmental stages.

Seizure medication and planned pregnancy: balancing the risks and outcomes

INTRODUCTION

The therapeutic management of women with epilepsy (WWE) of childbearing age can be complicated by the need to balance maternal/fetal risks related to seizure occurrence during gestation with the potential teratogenic risks related to the use of anti-seizure medications (ASMs).

AREAS COVERED

The authors review clinical evidence on seizure-related and ASM-related risks during pregnancy. Current regulatory indications are discussed, evaluating their impact on clinical practice, and ethical implications of pharmacological decisions are debated.

EXPERT OPINION

If properly informed about the maternal/fetal risks carried by different pharmacological choices, WWE can become the final decision makers regarding their care in every phase of their life. Over the coming years, analysis of aggregated pregnancy registry data on the structural impact, on the fetus, of low doses of valproate and of newer ASMs, together with analysis of the main population study data on functional (cognitive and behavioral) outcomes, could lead to huge advances, making choosing an ASM a less complex process for the clinician and a less painful decision for the woman. Future objectives should include identification of the potential role of the pharmacogenomic profile of WWE in determining the risk of fetal malformations.

Human forebrain organoids reveal connections between valproic acid exposure and autism risk

Valproic acid (VPA) exposure as an environmental factor that confers risk of autism spectrum disorder (ASD), its functional mechanisms in the human brain remain unclear since relevant studies are currently restricted to two-dimensional cell cultures and animal models. To identify mechanisms by which VPA contribute to ASD risk in human, here we used human forebrain organoids (hFOs), in vitro derived three-dimensional cell cultures that recapitulate key human brain developmental features. We identified that VPA exposure in hFOs affected the expression of genes enriched in neural development, synaptic transmission, oxytocin signaling, calcium, and potassium signaling pathways, which have been implicated in ASD. Genes (e.g., CAMK4, CLCN4, DPP10, GABRB3, KCNB1, PRKCB, SCN1A, and SLC24A2) that affected by VPA were significantly overlapped with those dysregulated in brains or organoids derived from ASD patients, and known ASD risk genes, as well as genes in ASD risk-associated gene coexpression modules. Single-cell RNA sequencing analysis showed that VPA exposure affected the expression of genes in choroid plexus, excitatory neuron, immature neuron, and medial ganglionic eminence cells annotated in hFOs. Microelectrode array further identified that VPA exposure in hFOs disrupted synaptic transmission. Taken together, this study connects VPA exposure to ASD pathogenesis using hFOs, which is valuable for illuminating the etiology of ASD and screening for potential therapeutic targets.

Increased volumes of lobule VI in a valproic acid model of autism are associated with worse set-shifting performance in male Long-Evan rats

Autism spectrum disorder (ASD) is a neurodevelopmental disorder with a skewed sex-based diagnostic ratio. While males are at a higher risk for ASD, it is critical to understand the neurobiology of the disorder to develop better treatments for both males and females. Our prior work has demonstrated that VPA (valproic acid) treated offspring had impaired performance on an attentional set-shifting task. The current study used MRI and regions of interest analyses to measure the volumes of cerebellar subregions in VPA and controls rats that had participated in the attentional set-shifting task. VPA males had significantly more volume in lobule VI compared to male controls. VPA female rats had significantly less volume in lobules I, IV and X compared to female controls. In addition, it was revealed that decreases in volume for VPA females was associated with worse performance. Males with increases in lobule VI were also impaired on the set-shifting task. Similar volumetric differences within the cerebellum have been observed in humans with ASD, which suggests that the VPA model is capturing some of the same brain changes observed in humans with ASD, and that these changes in volume may be impacting cognition.

A review of the evidence on the risk of congenital malformations and neurodevelopmental disorders in association with antiseizure medications during pregnancy

Introduction: The majority of women with epilepsy require treatment with antiseizure medications (ASM) throughout pregnancy. However, in utero exposure to several ASM has been associated with an increased risk of congenital malformations and/or neurodevelopmental disorders (CM/NDD) in the child, but observational evidence is methodologically heterogeneous.Areas covered: We critically evaluate current evidence on the risk of CM/NDD in children of women with epilepsy after in utero exposure to different ASM. We highlight characteristics of different data sources and discuss their benefits and drawbacks. This review includes evidence published before December 2020.Expert opinion: Given the lack of randomized controlled trials, evidence on in utero safety of ASM originates from methodologically heterogeneous post-marketing observational studies based on registries, prospective cohorts, and large electronic health databases. It has been clearly demonstrated that valproate is associated with a high risk of CM/NDD, whereas lamotrigine and levetiracetam are relatively safe. However, evidence is less explicit for other ASM. Reported risks vary depending on the size and origin of the underlying study population, the definition of exposure and outcomes, and other aspects of the study design. Increased collaboration between data sources to increase sample size is desirable.

Is the Medicines and Healthcare products Regulator Agency (MHRA) guidance on sodium valproate acceptable to women of childbearing age?

BACKGROUND

The UK Medicines and Healthcare products Regulatory Agency (MHRA) published guidelines restricting the use of sodium valproate in women of childbearing age unless they consented to the pregnancy prevention programme (PPP), receiving counselling by an epilepsy specialist, or meeting exclusion criteria.

METHODS

We contacted every woman of childbearing age on valproate for epilepsy in NHS Tayside (122).

RESULTS

Seventeen out of 122 (13.9%) responded to the initial invitation to attend, and 25 out of 122 (20.4%) responded to a letter sent to their GP. Twenty-five attended, 21 completed a consent form, seven switched to another drug and three attended to express dissatisfaction with the MHRA guidance. There were 53 patients identified with learning difficulties. Consent was only taken from three patients, with carers declining to sign consent because the patient was not sexually active.

CONCLUSION

Our study suggests that patients and carers do not wish to stop valproate or engage in PPP despite being made aware of MHRA guidance.

Phenotypic overlap between atopic dermatitis and autism

BACKGROUND

Autism, a childhood behavioral disorder, belongs to a large suite of diseases, collectively referred to as autism spectrum disorders (ASD). Though multifactorial in etiology, approximately 10% of ASD are associated with atopic dermatitis (AD). Moreover, ASD prevalence increases further as AD severity worsens, though these disorders share no common causative mutations. We assessed here the link between these two disorders in the standard, valproic acid mouse model of ASD. In prior studies, there was no evidence of skin involvement, but we hypothesized that cutaneous involvement could be detected in experiments conducted in BALB/c mice. BALB/c is an albino, laboratory-bred strain of the house mouse and is among the most widely used inbred strains used in animal experimentation.

METHODS

We performed our studies in valproic acid (VPA)-treated BALB/c hairless mice, a standard mouse model of ASD. Mid-trimester pregnant mice received a single intraperitoneal injection of either valproic acid sodium salt dissolved in saline or saline alone on embryonic day 12.5 and were housed individually until postnatal day 21. Only the brain and epidermis appeared to be affected, while other tissues remain unchanged. At various postnatal time points, brain, skin and blood samples were obtained for histology and for quantitation of tissue sphingolipid content and cytokine levels.

RESULTS

AD-like changes in ceramide content occurred by day one postpartum in both VPA-treated mouse skin and brain. The temporal co-emergence of AD and ASD, and the AD phenotype-dependent increase in ASD prevalence correlated with early appearance of cytokine markers (i.e., interleukin [IL]-4, 5, and 13), as well as mast cells in skin and brain. The high levels of interferon (IFN)γ not only in skin, but also in brain likely account for a significant decline in esterified very-long-chain N-acyl fatty acids in brain ceramides, again mimicking known IFNγ-induced changes in AD.

CONCLUSION

Baseline involvement of both AD and ASD could reflect concurrent neuro- and epidermal toxicity, possibly because both epidermis and neural tissues originate from the embryonic neuroectoderm. These studies illuminate the shared susceptibility of the brain and epidermis to a known neurotoxin, suggesting that the atopic diathesis could be extended to include ASD.

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.

Antiseizure medication use during pregnancy and risk of ASD and ADHD in children

OBJECTIVE

To determine whether children born to women who use antiseizure medications (ASMs) during pregnancy have higher risk of autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD) independent of confounding factors.

METHODS

We used Swedish register data (n = 14,614 children born 1996-2011 and followed up through 2013) to examine associations in children of women with epilepsy, using the largest sample to date and adjusting for a range of measured confounders. We examined maternal-reported first-trimester use of any ASM (22.7%) and the 3 most commonly reported individual drugs (valproic acid 4.8%, lamotrigine 6.8%, and carbamazepine 9.7%). We identified ASD with ICD-10 diagnoses and ADHD with ICD-10 diagnoses or filled prescriptions of ADHD medication.

RESULTS

Examination of individual drugs revealed that after adjustment for confounding, use of valproic acid was associated with ASD (hazard ratio [HR] 2.30, 95% confidence interval [CI] 1.53-3.47) and ADHD (HR 1.74, 95% CI 1.28-2.38). Whereas a small, nonstatistically significant association with ASD (HR 1.25, 95% CI = 0.88-1.79) and ADHD (HR 1.18, 95% CI 0.91-1.52) remained for reported use of carbamazepine, confounding explained all of the associations with lamotrigine (HRASD 0.86, 95% CI 0.67-1.53; HRADHD 1.01, 95% CI 0.67-1.53).

CONCLUSIONS

We found no evidence of risk related to exposure to lamotrigine, whereas we observed elevated risk of ASD and ADHD related to maternal use of valproic acid. Associations with carbamazepine were weak and not statistically significant. Our findings add to a growing body of evidence that suggests that certain ASMs may be safer than others in pregnancy.

Risk of early neurodevelopmental disorders associated with in utero exposure to valproate and other antiepileptic drugs: a nationwide cohort study in France

Information available on the risks of neurodevelopmental disorders (NDs) associated with in utero exposure to valproate (VPA) and to other antiepileptic drugs (AEDs) is limited. A nationwide population-based cohort study was conducted based on comprehensive data of the French National Health Data System (SNDS). Liveborn infants without brain malformation, born between January 2011 and December 2014, were followed from birth up to December 2016. NDs were identified based on diagnoses of mental or behavioural disorders and utilization of speech therapy, orthoptic or psychiatric services. The risk of NDs was compared between children exposed in utero to AED monotherapy and unexposed children, using Cox proportional hazard models adjusted for maternal and neonatal characteristics. The cohort included 1,721,990 children, 8848 of whom were exposed in utero to AED monotherapy. During a mean follow-up of 3.6 years, 15,458 children had a diagnosis of mental or behavioural disorder. In utero exposure to VPA was associated with an increased risk of NDs overall (aHR: 3.7; 95% CI 2.8–4.9) and among children born to a mother without mental illness (aHR 5.1; 95% CI 3.6–7.3). A dose–response relationship was demonstrated and the risk of NDs was more particularly increased for an exposure to VPA during the second or third trimesters of pregnancy. Among the other AEDs, only pregabalin was consistently associated with an increased risk of NDs (aHR: 1.5; 95% CI 1.0–2.1). This study confirms a four to fivefold increased risk of early NDs associated with exposure to VPA during pregnancy. The risk associated with other AEDs appears much lower.

Valproic acid treated female Long-Evans rats are impaired on attentional set-shifting

Autism spectrum disorder (ASD), is a neurodevelopmental disorder characterized by social deficits, communication impairments, restrictive behaviors, and cognitive flexibility deficits. The valproic acid (VPA) model of autism has been widely used to examine changes in rodent behavior and neurobiology to better understand ASD. This study examined social and anxiety behavior as well as cognitive flexibility in VPA and control offspring. Results for social behavior were consistent with prior studies showing reduced sociability in VPA rats and increased self-grooming, which may be viewed as a repetitive behavior. VPA rats also had deficits in performing the set-shifting task, with female VPA rats demonstrating greater impairment compared to female control rats and male VPA rats. These results support the hypothesis that females diagnosed with ASD may suffer from different symptoms and present a unique behavioral profile compared to males with ASD. Female VPA rats were also less likely to form an attentional set; offering evidence that the VPA model of autism is encompassing executive function deficits similar to those observed in humans with ASD.

Natural and forced neurogenesis in the adult brain: Mechanisms and their possible application to treat neurological disorders

Neural stem cells (NSCs) in the adult hippocampus generate new neurons via a process referred to as neurogenesis, supporting cognitive functions. Since altered neurogenesis has been reportedly associated with several diseases such as epilepsy, the molecular basis of NSC activity is an important focus in the study of neurogenesis. Furthermore, facilitation of neurogenesis in the injured brain would be an ideal approach to replenish lost neurons for damage recovery. However, natural neurogenesis by endogenous NSCs in the adult brain is insufficient for complete recovery after severe injury. Recent advances in understanding forced neurogenesis from brain-resident non-neuronal cells by direct reprogramming and clearing hurdles to achieve it have improved the ability to replace damaged neurons in the brain. In this review, we describe molecular mechanisms underlying natural and forced neurogenesis, and discuss future directions for treatments of diseases in the central nervous system.

Behavioral problems in children of mothers with epilepsy prenatally exposed to valproate, carbamazepine, lamotrigine, or levetiracetam monotherapy

Objective

To examine the behavioral functioning of children prenatally exposed to carbamazepine (CBZ), lamotrigine (LTG), levetiracetam (LEV), or valproate (VPA) monotherapy.

Methods

In collaboration with the European Registry of Antiepileptic Drugs and Pregnancy (EURAP), the Dutch EURAP & Development study was designed, a prospective observational study. Between January 2015 and March 2018, the Child Behavior Checklist and the Social Emotional Questionnaire were used to examine the nature and severity of behavioral problems. VPA‐exposed children were compared to children exposed to CBZ, LTG, or LEV, taking potential confounders into account. A direct comparison was also made between LTG and LEV, as these are first‐choice treatments for many women with epilepsy of childbearing potential.

Results

Of the 405 invited, 181 children were included; 26 were exposed to VPA, 37 to CBZ, 88 to LTG, and 30 to LEV. For most children, both parents completed the behavioral questionnaires. Across all four antiepileptic drug (AED) exposure groups, high percentages of children with clinically relevant behavior problems were found, with behavioral problems occurring in 32% of VPA‐exposed children, 14% of CBZ, 16% of LTG, and 14% of LEV. After controlling for potential confounders, VPA‐exposed children had significantly more social problems than those exposed to LTG (−2.8, 95% confidence interval [CI] = −5.2 to −0.4; P = 0.022) or LEV (−3.2, CI: −6.1 to −0.3; P = 0.028), and significantly more attention problems than LEV‐exposed children (−3.7, CI: −6.7 to −0.8; P = 0.013). LTG‐exposed children had significantly more attention deficit (−9.2, CI: −17.3 to 1.1; P = 0.026), but significantly less anxious behavior when compared to LEV‐exposed children (9.0, CI: 0.3‐17.6; P = 0.042).

Significance

Compared to population norms, a high proportion of children of mothers with epilepsy exposed prenatally to monotherapy with four common AEDs had clinical behavioral problems reported by parents. Different patterns were seen, with some but not all subscales raised for all AED exposure groups. It is important that prenatally AED‐exposed children are regularly screened for behavioral problems so that appropriate help can be provided.

Rescue of PB-resistant neonatal seizures with single-dose of small-molecule TrkB antagonist show long-term benefits

A recently characterized CD-1 mouse model of phenobarbital (PB)-resistant neonatal ischemic-seizures (i.e.; unilateral carotid ligation) was shown to be associated with age-dependent (P7 vs. P10) acute seizure severity and PB-efficacy (i.e.; PB-resistant vs. PB-responsive). ANA12, a novel small-molecule TrkB antagonist, rescued the PB-resistance at P7 in a dose-dependent manner and prevented the post-ischemic downregulation of KCC2, the chief Cl- extruder in neurons. The long-term consequences of this novel rescue-intervention with ANA12 + PB in P7 and P10 ligated pups was investigated and compared to the standard first-line protocol of PB-alone loading dose. The mice underwent neurobehavioral testing, 24 h video-EEG-EMG monitoring, and immunohistochemistry in ipsi- and contralateral cortices as adults following the neonatal interventions. ANA12 + PB rescued the emergence of hyperactivity in post-ischemic P7, but not in P10 pups as adults. ANA12 + PB administration at neither P7 nor P10 significantly altered 24 h macro-sleep architecture in adults when compared to PB-alone. Behavioral state-dependent gamma (35-50 Hz) power homeostasis showed the most significant between-group differences that were age-dependent. ANA12 + PB treatment, but not PB-alone, rescued the loss of gamma power homeostasis present in P7 ligate-control but absent in P10 ligate group, highlighting the age-dependence. In contrast, PB-alone treatment, but not ANA12+PB, significantly reduced the elevated delta-AUC observed in P10 ligate-controls, when PB is efficacious by itself. These results indicate that the rescue of acute PB-resistant neonatal seizures using a novel intervention positively modulates the long-term outcomes at P7 when the seizures are refractory.

Maternal valproic acid exposure leads to neurogenesis defects and autism-like behaviors in non-human primates

Despite the substantial progress made in identifying genetic defects in autism spectrum disorder (ASD), the etiology for majority of ASD individuals remains elusive. Maternal exposure to valproic acid (VPA), a commonly prescribed antiepileptic drug during pregnancy in human, has long been considered a risk factor to contribute to ASD susceptibility in offspring from epidemiological studies in humans. The similar exposures in murine models have provided tentative evidence to support the finding from human epidemiology. However, the apparent difference between rodent and human poses a significant challenge to extrapolate the findings from rodent models to humans. Here we report for the first time the neurodevelopmental and behavioral outcomes of maternal VPA exposure in non-human primates. Monkey offspring from the early maternal VPA exposure have significantly reduced NeuN-positive mature neurons in prefrontal cortex (PFC) and cerebellum and the Ki67-positive proliferating neuronal precursors in the cerebellar external granular layer, but increased GFAP-positive astrocytes in PFC. Transcriptome analyses revealed that maternal VPA exposure disrupted the expression of genes associated with neurodevelopment in embryonic brain in offspring. VPA-exposed juvenile offspring have variable presentations of impaired social interaction, pronounced stereotypies, and more attention on nonsocial stimuli by eye tracking analysis. Our findings in non-human primates provide the best evidence so far to support causal link between maternal VPA exposure and neurodevelopmental defects and ASD susceptibility in humans.

Diagnosis and management of individuals with Fetal Valproate Spectrum Disorder; a consensus statement from the European Reference Network for Congenital Malformations and Intellectual Disability

BACKGROUND

A pattern of major and minor congenital anomalies, facial dysmorphic features, and neurodevelopmental difficulties, including cognitive and social impairments has been reported in some children exposed to sodium valproate (VPA) during pregnancy. Recognition of the increased risks of in utero exposure to VPA for congenital malformations, and for the neurodevelopmental effects in particular, has taken many years but these are now acknowledged following the publication of the outcomes of several prospective studies and registries. As with other teratogens, exposure to VPA can have variable effects, ranging from a characteristic pattern of major malformations and significant intellectual disability to the other end of the continuum, characterised by facial dysmorphism which is often difficult to discern and a more moderate effect on neurodevelopment and general health. It has become clear that some individuals with FVSD have complex needs requiring multidisciplinary care but information regarding management is currently lacking in the medical literature.

METHODS

An expert group was convened by ERN-ITHACA, the European Reference Network for Congenital Malformations and Intellectual Disability comprised of professionals involved in the care of individuals with FVSD and with patient representation. Review of published and unpublished literature concerning management of FVSD was undertaken and the level of evidence from these sources graded. Management recommendations were made based on strength of evidence and consensus expert opinion, in the setting of an expert consensus meeting. These were then refined using an iterative process and wider consultation.

RESULTS

Whilst there was strong evidence regarding the increase in risk for major congenital malformations and neurodevelopmental difficulties there was a lack of high level evidence in other areas and in particular in terms of optimal clinical management.. The expert consensus approach facilitated the formulation of management recommendations, based on literature evidence and best practice. The outcome of the review and group discussions leads us to propose the term Fetal Valproate Spectrum Disorder (FVSD) as we feel this better encompasses the broad range of effects seen following VPA exposure in utero.

CONCLUSION

The expert consensus approach can be used to define the best available clinical guidance for the diagnosis and management of rare disorders such as FVSD. FVSD can have medical, developmental and neuropsychological impacts with life-long consequences and affected individuals benefit from the input of a number of different health professionals.

Rational use of mesenchymal stem cells in the treatment of autism spectrum disorders

Autism and autism spectrum disorders (ASD) refer to a range of conditions characterized by impaired social and communication skills and repetitive behaviors caused by different combinations of genetic and environmental influences. Although the pathophysiology underlying ASD is still unclear, recent evidence suggests that immune dysregulation and neuroinflammation play a role in the etiology of ASD. In particular, there is direct evidence supporting a role for maternal immune activation during prenatal life in neurodevelopmental conditions. Currently, the available options of behavioral therapies and pharmacological and supportive nutritional treatments in ASD are only symptomatic. Given the disturbing rise in the incidence of ASD, and the fact that there is no effective pharmacological therapy for ASD, there is an urgent need for new therapeutic options. Mesenchymal stem cells (MSCs) possess immunomodulatory properties that make them relevant to several diseases associated with inflammation and tissue damage. The paracrine regenerative mechanisms of MSCs are also suggested to be therapeutically beneficial for ASD. Thus the underlying pathology in ASD, including immune system dysregulation and inflammation, represent potential targets for MSC therapy. This review will focus on immune dysfunction in the pathogenesis of ASD and will further discuss the therapeutic potential for MSCs in mediating ASD-related immunological disorders.

Association of Prenatal Exposure to Valproate and Other Antiepileptic Drugs With Risk for Attention-Deficit/Hyperactivity Disorder in Offspring

IMPORTANCE

Valproate is an antiepileptic drug (AED) used in the treatment of epilepsy and many other neurological and psychiatric disorders. Its use in pregnancy is associated with increased risks of congenital malformations and adverse neurodevelopment in the offspring and may be associated with an increased risk of attention-deficit/hyperactivity disorder (ADHD).

OBJECTIVE

To determine whether prenatal exposure to valproate and other AEDs is associated with an increased risk of ADHD in the offspring.

DESIGN, SETTING, AND PARTICIPANTS

This was a population-based cohort study of all live-born singleton children in Denmark from January 1, 1997, to December 31, 2011 (N = 913 302). Information on prenatal exposure to AEDs, including valproate, was obtained from the Danish National Prescription Registry and all children with ADHD were identified (children with diagnosed ADHD in the Danish Psychiatric Central Research Register or children who redeemed a prescription for ADHD medication). The cohort was followed up from birth until the day of the ADHD diagnosis, death, emigration, or December 31, 2015, whichever came first. Data were analyzed in September 2018.

EXPOSURES

Maternal use of valproate and other AEDs in pregnancy.

MAIN OUTCOMES AND MEASURES

Cox regression estimates of the hazard ratio of ADHD. Estimates were adjusted for potential confounders.

RESULTS

The cohort included 913 302 children (mean age at end of study, 10.1 years; median age, 9.4 years; interquartile range, 7.2-12.8 years; 468 708 [51.3%] male). A total of 580 were identified as having been exposed to valproate during pregnancy; of them, 49 (8.4%) had ADHD. Among the 912 722 children who were unexposed to valproate, 29 396 (3.2%) had ADHD. Children with prenatal valproate exposure had a 48% increased risk of ADHD (adjusted hazard ratio, 1.48; 95% CI, 1.09-2.00) compared with children with no valproate exposure. The absolute 15-year risk of ADHD was 4.6% (95% CI, 4.5%-4.6%) in children unexposed to valproate and 11.0% (95% CI, 8.2%-14.2%) in children who were exposed to valproate in pregnancy. No associations were found between other AEDs and ADHD.

CONCLUSIONS AND RELEVANCE

Maternal use of valproate, but not other AEDs, during pregnancy was associated with an increased risk of ADHD in the offspring. These findings have important implications for the counseling of women of childbearing potential using valproate.

Ectopic neurogenesis induced by prenatal antiepileptic drug exposure augments seizure susceptibility in adult mice

Recent clinical studies suggest that environmental insults, such as valproic acid (VPA) exposure, in utero can have adverse effects on brain function of the offspring in later life, although the underlying mechanisms of these impairments remain poorly understood. By focusing on the property of neural stem/progenitor cells (NS/PCs) residing in the adult hippocampus, we identified the mechanism of increased seizure sensitivity in prenatally VPA-exposed adult mice. Furthermore, we found that voluntary exercise can overcome the adverse effects through normalizing VPA-induced transcriptome alterations in NS/PCs. We believe that our study provides insights for further understanding and developing treatment strategies for neurological disorders induced by prenatal environmental insults.

Epilepsy is a neurological disorder often associated with seizure that affects ∼0.7% of pregnant women. During pregnancy, most epileptic patients are prescribed antiepileptic drugs (AEDs) such as valproic acid (VPA) to control seizure activity. Here, we show that prenatal exposure to VPA in mice increases seizure susceptibility in adult offspring through mislocalization of newborn neurons in the hippocampus. We confirmed that neurons newly generated from neural stem/progenitor cells (NS/PCs) are integrated into the granular cell layer in the adult hippocampus; however, prenatal VPA treatment altered the expression in NS/PCs of genes associated with cell migration, including CXC motif chemokine receptor 4 (Cxcr4), consequently increasing the ectopic localization of newborn neurons in the hilus. We also found that voluntary exercise in a running wheel suppressed this ectopic neurogenesis and countered the enhanced seizure susceptibility caused by prenatal VPA exposure, probably by normalizing the VPA-disrupted expression of multiple genes including Cxcr4 in adult NS/PCs. Replenishing Cxcr4 expression alone in NS/PCs was sufficient to overcome the aberrant migration of newborn neurons and increased seizure susceptibility in VPA-exposed mice. Thus, prenatal exposure to an AED, VPA, has a long-term effect on the behavior of NS/PCs in offspring, but this effect can be counteracted by a simple physical activity. Our findings offer a step to developing strategies for managing detrimental effects in offspring exposed to VPA in utero.

Epigenetic cerebellar diseases

Epigenetics is a growing field of knowledge that is changing our understanding of pathologic processes. For many cerebellar disorders, recent discoveries of epigenetic mechanisms help us to understand their pathophysiology. In this chapter, a short explanation of each epigenetic mechanism (including methylation, histone modification, and miRNA) is followed by references to those cerebellar disorders in which relevant epigenetic advances have been made. The importance of normal timing and distribution of methylation during neurodevelopment is explained. Abnormal methylation and altered gene expression in the developing cerebellum have been related to neurodevelopmental disorders such as autism, Rett syndrome, and fragile X syndrome. DNA packaging by histones is another important epigenetic mechanism in cerebellar functioning. Current knowledge of histone abnormalities in cerebellar diseases such as Friedreich ataxia and spinocerebellar ataxias is reviewed, including implications for new therapeutic approaches to these degenerative diseases. Finally, micro RNAs, the third mechanism to modulate DNA expression, and their role in normal cerebellar development and disease are described. Understanding how genetic and epigenetic mechanisms interact not only in normal cerebellar development but also in disease is a great challenge. However, such understanding will lead to promising new therapeutic possibilities as is already occurring in other areas of medicine.

Comparative safety of antiepileptic drugs for neurological development in children exposed during pregnancy and breast feeding: a systematic review and network meta-analysis

OBJECTIVES

Compare the safety of antiepileptic drugs (AEDs) on neurodevelopment of infants/children exposed in utero or during breast feeding.

DESIGN AND SETTING

Systematic review and Bayesian random-effects network meta-analysis (NMA). MEDLINE, EMBASE and the Cochrane Central Register of Controlled Trials were searched until 27 April 2017. Screening, data abstraction and quality appraisal were completed in duplicate by independent reviewers.

PARTICIPANTS

29 cohort studies including 5100 infants/children.

INTERVENTIONS

Monotherapy and polytherapy AEDs including first-generation (carbamazepine, clobazam, clonazepam, ethosuximide, phenobarbital, phenytoin, primidone, valproate) and newer-generation (gabapentin, lamotrigine, levetiracetam, oxcarbazepine, topiramate, vigabatrin) AEDs. Epileptic women who did not receive AEDs during pregnancy or breast feeding served as the control group.

PRIMARY AND SECONDARY OUTCOME MEASURES

Cognitive developmental delay and autism/dyspraxia were primary outcomes. Attention-deficit hyperactivity disorder, language delay, neonatal seizures, psychomotor developmental delay and social impairment were secondary outcomes.

RESULTS

The NMA on cognitive developmental delay (11 cohort studies, 933 children, 18 treatments) suggested that among all AEDs only valproate was statistically significantly associated with more children experiencing cognitive developmental delay compared with control (OR=7.40, 95% credible interval (CrI) 3.00 to 18.46). The NMA on autism (5 cohort studies, 2551 children, 12 treatments) suggested that oxcarbazepine (OR 13.51, CrI 1.28 to 221.40), valproate (OR 17.29, 95% CrI 2.40 to 217.60), lamotrigine (OR 8.88, CrI 1.28 to 112.00) and lamotrigine+valproate (OR 132.70, CrI 7.41 to 3851.00) were associated with significantly greater odds of developing autism compared with control. The NMA on psychomotor developmental delay (11 cohort studies, 1145 children, 18 treatments) found that valproate (OR 4.16, CrI 2.04 to 8.75) and carbamazepine+phenobarbital+valproate (OR 19.12, CrI 1.49 to 337.50) were associated with significantly greater odds of psychomotor delay compared with control.

CONCLUSIONS

Valproate alone or combined with another AED is associated with the greatest odds of adverse neurodevelopmental outcomes compared with control. Oxcarbazepine and lamotrigine were associated with increased occurrence of autism. Counselling is advised for women considering pregnancy to tailor the safest regimen.

TRIAL REGISTRATION NUMBER

PROSPERO database (CRD42014008925).

An Update on Maternal Use of Antiepileptic Medications in Pregnancy and Neurodevelopment Outcomes

Antiepileptic drugs (AEDs) are prescribed commonly to women of childbearing age. In utero exposure to some AEDs can have significant cognitive and behavioral consequences for the unborn child. Recently, prospective studies of women taking AEDs during pregnancy have added significantly to our understanding of cognitive and behavioral teratogenic risks posed by fetal AED exposure. Valproate is clearly associated with impaired cognitive development as well as an increased risk of disorders such as autism and autism spectrum disorder. Exposure to carbamazepine, lamotrigine, levetiracetam, or phenytoin monotherapy is associated with more favorable cognitive and behavioral outcomes than valproate, but more data are required to clarify if these AEDs have more subtle effects on cognition and behavior. There are insufficient data on the developmental effects of other AEDs in humans. Further, the underlying mechanisms of cognitive teratogenesis are poorly understood, including the genetic factors that affect susceptibility to AEDs.

A single low dose of valproic acid in late prenatal life alters postnatal behavior and glutamic acid decarboxylase levels in the mouse

RATIONALE

Rodents exposed to valproic acid (VPA) in prenatal life exhibit post-natal characteristics analogous to autism spectrum disorder (ASD). Many previous studies used relatively high doses of VPA during early pregnancy, potentially confounding interpretation because the offspring are the 'survivors' of a toxic insult. Low dose or late gestation exposure has not been widely studied.

OBJECTIVES

We examined the behavioral sequelae of late gestation exposure to low dose VPA in the mouse. We also examined postnatal levels of glutamic acid decarboxylase (GAD65 and GAD67) as markers for GABA neurons, because GABA pathology and subsequent excitatory/inhibitory imbalance is strongly implicated in ASD.

METHODS

Pregnant C57BL/6N mice received a single subcutaneous injection of 100 or 200mg/kg on gestation day 17. The control group received a saline injection on the same day. The offspring were tested in a battery of behavioral tests in adolescence and adulthood. Six brain regions were harvested and GAD65 and GAD67 were measured by western blotting.

RESULTS

Compared to saline-exposed controls, adult mice exposed to prenatal VPA had impaired novel object exploration and fear conditioning anomalies. GAD67 was decreased in midbrain, olfactory bulb, prefrontal cortex and increased in cerebellum, hippocampus and striatum; GAD65 was decreased in all 6 regions.

CONCLUSIONS

Our results suggest that a low dose of VPA in late pregnancy has persistent effects on brain development, and in particular the GABA system, which may be relevant to ASD. Further attention to the impact of gestation time and dose of exposure in VPA-induced ASD models is encouraged.

The treatment of epilepsy in pregnancy: The neurodevelopmental risks associated with exposure to antiepileptic drugs

A number of antiepileptic drugs (AEDs) have been confirmed as teratogens due to their association with an increased malformation rate. The majority of research to date does not find an association between prenatal exposure to monotherapy carbamazepine, lamotrigine or phenytoin and neurodevelopmental outcome in comparison to control children and noted higher abilities in comparison to children exposed to valproate; but further work is needed before conclusions can be drawn. Data for levetiracetam was limited to one study, as was the evidence for topiramate. Sodium valproate exposure appeared to carry a dose dependent risk to the developing brain, with evidence of reduced levels of IQ, poorer verbal abilities and increased rate of autistic spectrum disorder both in comparison to control children and children exposed to other AEDs. The severity of the neurodevelopmental deficits associated with prenatal exposure to valproate highlight the critical need to consider neurodevelopmental outcomes as a central aspect of teratological research.

In utero Exposure to β-2-Adrenergic Receptor Agonist Drugs and Risk for Autism Spectrum Disorders

OBJECTIVES

The purpose of this study was to investigate associations between use of β-2-adrenergic receptor (B2AR) agonist drugs during pregnancy and risk for autism spectrum disorders (ASD).

METHODS

A case-control study was conducted by using Denmark's health and population registers. Among children born between 1997 and 2006, 5200 cases with ASD admission diagnoses and 52 000 controls without ASD were identified and individually matched on month and year of birth. Conditional logistic regression models were used to estimate odds ratios (OR) and confidence intervals (CI) for any B2AR agonist exposure during pregnancy, preconception, and by trimester.

RESULTS

In total, 3.7% of cases and 2.9% of controls were exposed to B2ARs during pregnancy. Use of B2ARs during pregnancy was associated with increased risk of ASD, even after adjustment for maternal asthma and other covariates (OR: 1.3, 95% CI: 1.1-1.5). The elevated risk was observed with use of B2AR during preconception (OR: 1.3, 95% CI: 1.0-1.6), first trimester (OR: 1.3, 95% CI: 1.1-1.5), second trimester (OR: 1.5, 95% CI: 1.1-1.7), and the third trimester (OR: 1.4, 95% CI: 1.1-1.7). There was some evidence that longer B2AR within-pregnancy use was associated with the increased risk.

CONCLUSIONS

B2AR agonist exposure during pregnancy may be associated with an increased risk for ASD. If the effect is real, any intervention must be balanced against benefits of indicated medication use by pregnant women.

Behavioral outcomes in children exposed prenatally to lamotrigine, valproate, or carbamazepine

OBJECTIVES

To evaluate adaptive behavior outcomes of children prenatally exposed to lamotrigine, valproate, or carbamazepine, and to determine if these outcomes were dose-dependent.

METHODS

Data were collected from women enrolled in the North American Anti epileptic Drug (AED) Pregnancy Registry who had taken lamotrigine, valproate, or carbamazepine monotherapies throughout pregnancy to suppress seizures. The adaptive behavior of 252 exposed children (including 104 lamotrigine-exposed, 97 carbamazepine-exposed, and 51 valproate-exposed), ages 3- to 6-years-old, was measured using the Vineland-II Adaptive Behavior Scales, administered to each mother by telephone. Mean Adaptive Behavior Composite (ABC), domain standard scores for communication, daily living, socialization and motor skills, and adaptive levels were analyzed and correlated with first trimester drug dose.

RESULTS

After adjusting for maternal age, education, folate use, cigarette and alcohol exposure, gestational age, and birth weight by propensity score analysis, the mean ABC score for valproate-exposed children was 95.6 (95% CI [91, 101]), versus 100.8 (95% CI [98, 103]) and 103.5 (95% CI [101, 106]) for carbamazepine- and lamotrigine-exposed children, respectively (ANOVA; p=0.017). Significant differences were observed among the three drug groups in the ABC (p=0.017), socialization (p=0.026), and motor (p=0.018) domains, with a trend toward significance in the communication domain (p=0.053). Valproate-exposed children scored lowest and lamotrigine-exposed children scored highest in every category. Valproate-exposed children were most likely to perform at a low or moderately low adaptive level in each category. Higher valproate dose was associated with significantly lower ABC (p=0.020), socialization (p=0.009), and motor (p=0.041) scores before adjusting for confounders. After adjusting for the above variables, increasing VPA dose was associated with decreasing Vineland scores in all domains, but the relationships were not statistically significant. No dose effect was observed for carbamazepine or lamotrigine.

CONCLUSIONS

Unlike carbamazepine and lamotrigine, prenatal valproate exposure was associated with adaptive behavior impairments with specific deficits in socialization and motor function, along with a relative weakness in communication. Increasing valproate dose was associated with a decline in adaptive functioning. This finding of a linear dose-dependent teratogenic effect suggests that valproate should be avoided at any dose during pregnancy. However, some women with epilepsy controlled only by valproate will decide, in consultation with their provider, that the benefits of continuing valproate during pregnancy outweigh the fetal risks. Faced with difficult choices, clinicians should be supportive as these patients consider their options.

Foetal safety of old and new antiepileptic drugs

INTRODUCTION

Drugs teratogenicity has been studied for many years, especially teratogenic effects of antiepileptic drugs, because of the important impact that epilepsy has always had for young women, but data from literature are often conflicting.

AREAS COVERED

We have carried out a critical review of all human studies about the antiepileptic drugs teratogenicity. A systematic search was performed in Medline and PubMed up to May 1, 2015. The use of older antiepileptic drugs in pregnancy is associated with an increased risk of fetus malformations; in particular, Valproate can determine neural-tube-like defects; in Phenytoin and Phenobarbital-exposed pregnancies, orofacial clefts, cardiac and genitourinary malformations are the major anomalies described. Spina bifida is the only specific major congenital malformation significantly associated with exposure to Carbamazepine monotherapy Despite the small number of studies on the teratogenic effects of new antiepileptic drugs, the analysis of the literature shows that exposure of the fetus to the new antiepileptic drugs is associated with a lower risk of major congenital malformations compared to the use of older drugs.

EXPERT OPINION

Where possible, Valproate should be avoided in women of childbearing potential. Results about the safety of newer antiepileptic drugs require validation and further investigation.

Grouping of histone deacetylase inhibitors and other toxicants disturbing neural crest migration by transcriptional profiling

Functional assays, such as the "migration inhibition of neural crest cells" (MINC) developmental toxicity test, can identify toxicants without requiring knowledge on their mode of action (MoA). Here, we were interested, whether (i) inhibition of migration by structurally diverse toxicants resulted in a unified signature of transcriptional changes; (ii) whether statistically-identified transcript patterns would inform on compound grouping even though individual genes were little regulated, and (iii) whether analysis of a small group of biologically-relevant transcripts would allow the grouping of compounds according to their MoA. We analyzed transcripts of 35 'migration genes' after treatment with 16 migration-inhibiting toxicants. Clustering, principal component analysis and correlation analyses of the data showed that mechanistically related compounds (e.g. histone deacetylase inhibitors (HDACi), PCBs) triggered similar transcriptional changes, but groups of structurally diverse toxicants largely differed in their transcriptional effects. Linear discriminant analysis (LDA) confirmed the specific clustering of HDACi across multiple separate experiments. Similarity of the signatures of the HDACi trichostatin A and suberoylanilide hydroxamic acid to the one of valproic acid (VPA), suggested that the latter compound acts as HDACi when impairing neural crest migration. In conclusion, the data suggest that (i) a given functional effect (e.g. inhibition of migration) can be associated with highly diverse signatures of transcript changes; (ii) statistically significant grouping of mechanistically-related compounds can be achieved on the basis of few genes with small regulations. Thus, incorporation of mechanistic markers in functional in vitro tests may support read-across procedures, also for structurally un-related compounds.

A multifactorial analysis of the pregnancy outcomes in cytomegalovirus-infected women

AIMS

To investigate the impacts of cytomegalovirus (CMV) viral load, TORCH (toxoplasmosis, others, rubella, CMV and herpes) coinfections, CMV glycoprotein B (gB) genotypes and maternal genetic polymorphisms on pregnancy outcomes among CMV-infected women.

METHODS

A total of 731 CMV-infected pregnant women (634 and 97 with normal and adverse pregnancy outcomes, respectively) were recruited. CMV load quantification and screening of TORCH coinfections were performed by using real-time polymerase chain reaction (PCR) and immunodetection techniques, respectively. Genotyping of CMV gB and maternal NFKB1 -94 ins/del, NFKBIA -826C/T and -881A/G polymorphisms was performed by using PCR-restriction fragment length polymorphism.

RESULTS

We found that the mean CMV viral load in women with adverse pregnancy outcomes was significantly higher than that in women with normal outcomes at all pregnancy stages (p < 0.01). We also found that TORCH coinfections resulted in a 1.65-fold (95% CI = 1.00-2.73) increase in the risk of adverse pregnancy outcomes (p = 0.05). Additionally, we noticed no significant difference in the distribution of CMV gB genotypes between women with normal and adverse pregnancy outcomes (p = 0.42). We also observed that the ins/ins variant genotype of the NFKB1 polymorphism could reduce the risk of adverse pregnancy outcomes (OR = 0.38, 95% CI = 0.15-0.98; p = 0.04).

CONCLUSION

CMV viral load, TORCH coinfections and maternal NFKB1 polymorphism could influence pregnancy outcomes among CMV-infected women.

Tactile stimulation improves neuroanatomical pathology but not behavior in rats prenatally exposed to valproic acid

Autism is a severe neurodevelopmental disorder with a population prevalence of 1 in 68, and dramatically increasing. While no single pharmacologic intervention has successfully targeted the core symptoms of autism, emerging evidence suggests that postnatal environmental manipulations may offer greater therapeutic efficacy. Massage therapy, or tactile stimulation (TS), early in life has repeatedly been shown to be an effective, low-cost, therapeutic approach in ameliorating the cognitive, social, and emotional symptoms of autism. While early TS treatment attenuates many of the behavioral aberrations among children with autism, the neuroanatomical correlates driving such changes are unknown. The present study assessed the therapeutic effects of early TS treatment on behavior and neuroanatomy using the valproic acid (VPA) rodent model of autism. Rats were prenatally exposed to VPA on gestational day 12.5 and received TS shortly following birth. Whereas TS reversed almost all the VPA-induced alterations in neuroanatomy, it failed to do so behaviorally. The TS VPA animals, when compared to VPA animals, did not exhibit altered or improved behavior in the delayed non-match-to-sample T-maze, Whishaw tray reaching, activity box, or elevated plus maze tasks. Anatomically, however, there were significant increases in dendritic branching and spine density in the medial prefrontal cortex, orbital frontal cortex, and amygdala in VPA animals following early TS treatment, suggesting a complete reversal or remediation of the VPA-induced effects in these regions. The results suggest that postnatal TS, during a critical period in development, acts as a powerful reorganization tool that can ameliorate the neuroanatomical consequences of prenatal VPA exposure.

Treatment for epilepsy in pregnancy: neurodevelopmental outcomes in the child

BACKGROUND

Accumulating evidence suggests an association between prenatal exposure to antiepileptic drugs (AEDs) and increased risk of both physical anomalies and neurodevelopmental impairment. Neurodevelopmental impairment is characterised by either a specific deficit or a constellation of deficits across cognitive, motor and social skills and can be transient or continuous into adulthood. It is of paramount importance that these potential risks are identified, minimised and communicated clearly to women with epilepsy.

OBJECTIVES

To assess the effects of prenatal exposure to commonly prescribed AEDs on neurodevelopmental outcomes in the child and to assess the methodological quality of the evidence.

SEARCH METHODS

We searched the Cochrane Epilepsy Group Specialized Register (May 2014), Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library (2014, Issue 4), MEDLINE (via Ovid) (1946 to May 2014), EMBASE (May 2014), Pharmline (May 2014) and Reprotox (May 2014). No language restrictions were imposed. Conference abstracts from the last five years were reviewed along with reference lists from the included studies.

SELECTION CRITERIA

Prospective cohort controlled studies, cohort studies set within pregnancy registers and randomised controlled trials were selected for inclusion. Participants were women with epilepsy taking AED treatment; the two control groups were women without epilepsy and women with epilepsy who were not taking AEDs during pregnancy.

DATA COLLECTION AND ANALYSIS

Three authors (RB, JW and JG) independently selected studies for inclusion. Data extraction and risk of bias assessments were completed by five authors (RB, JW, AS, NA, AJM). The primary outcome was global cognitive functioning. Secondary outcomes included deficits in specific cognitive domains or prevalence of neurodevelopmental disorders. Due to substantial variation in study design and outcome reporting only limited data synthesis was possible.

MAIN RESULTS

Twenty-two prospective cohort studies were included and six registry based studies. Study quality varied. More recent studies tended to be larger and to report individual AED outcomes from blinded assessments, which indicate improved methodological quality.The developmental quotient (DQ) was lower in children exposed to carbamazepine (CBZ) (n = 50) than in children born to women without epilepsy (n = 79); mean difference (MD) of -5.58 (95% confidence interval (CI) -10.83 to -0.34, P = 0.04). The DQ of children exposed to CBZ (n = 163) was also lower compared to children of women with untreated epilepsy (n = 58) (MD -7.22, 95% CI -12.76 to - 1.67, P = 0.01). Further analysis using a random-effects model indicated that these results were due to variability within the studies and that there was no significant association with CBZ. The intelligence quotient (IQ) of older children exposed to CBZ (n = 150) was not lower than that of children born to women without epilepsy (n = 552) (MD -0.03, 95% CI -3.08 to 3.01, P = 0.98). Similarly, children exposed to CBZ (n = 163) were not poorer in terms of IQ in comparison to the children of women with untreated epilepsy (n = 87) (MD 1.84, 95% CI -2.13 to 5.80, P = 0.36). The DQ in children exposed to sodium valproate (VPA) (n = 123) was lower than the DQ in children of women with untreated epilepsy (n = 58) (MD -8.72, 95% -14.31 to -3.14, P = 0.002). The IQ of children exposed to VPA (n = 76) was lower than for children born to women without epilepsy (n = 552) (MD -8.94, 95% CI -11.96 to -5.92, P < 0.00001). Children exposed to VPA (n = 89) also had lower IQ than children born to women with untreated epilepsy (n = 87) (MD -8.17, 95% CI -12.80 to -3.55, P = 0.0005).In terms of drug comparisons, in younger children there was no significant difference in the DQ of children exposed to CBZ (n = 210) versus VPA (n=160) (MD 4.16, 95% CI -0.21 to 8.54, P = 0.06). However, the IQ of children exposed to VPA (n = 112) was significantly lower than for those exposed to CBZ (n = 191) (MD 8.69, 95% CI 5.51 to 11.87, P < 0.00001). The IQ of children exposed to CBZ (n = 78) versus lamotrigine (LTG) (n = 84) was not significantly different (MD -1.62, 95% CI -5.44 to 2.21, P = 0.41). There was no significant difference in the DQ of children exposed to CBZ (n = 172) versus phenytoin (PHT) (n = 87) (MD 3.02, 95% CI -2.41 to 8.46, P = 0.28). The IQ abilities of children exposed to CBZ (n = 75) were not different from the abilities of children exposed to PHT (n = 45) (MD -3.30, 95% CI -7.91 to 1.30, P = 0.16). IQ was significantly lower for children exposed to VPA (n = 74) versus LTG (n = 84) (MD -10.80, 95% CI -14.42 to -7.17, P < 0.00001). DQ was higher in children exposed to PHT (n = 80) versus VPA (n = 108) (MD 7.04, 95% CI 0.44 to 13.65, P = 0.04). Similarly IQ was higher in children exposed to PHT (n = 45) versus VPA (n = 61) (MD 9.25, 95% CI 4.78 to 13.72, P < 0.0001). A dose effect for VPA was reported in six studies, with higher doses (800 to 1000 mg daily or above) associated with a poorer cognitive outcome in the child. We identified no convincing evidence of a dose effect for CBZ, PHT or LTG. Studies not included in the meta-analysis were reported narratively, the majority of which supported the findings of the meta-analyses.

AUTHORS' CONCLUSIONS

The most important finding is the reduction in IQ in the VPA exposed group, which are sufficient to affect education and occupational outcomes in later life. However, for some women VPA is the most effective drug at controlling seizures. Informed treatment decisions require detailed counselling about these risks at treatment initiation and at pre-conceptual counselling. We have insufficient data about newer AEDs, some of which are commonly prescribed, and further research is required. Most women with epilepsy should continue their medication during pregnancy as uncontrolled seizures also carries a maternal risk.

Risks of neurobehavioral teratogenicity associated with prenatal exposure to valproate monotherapy: a systematic review with regulatory repercussions

Beyond its formal indications (epilepsy, bipolar disorder, and migraine), valproate sodium (VPA) is widely used in a number of other clinical conditions. Recently, however, the U.S. Food and Drug Administration (FDA) issued a warning regarding a decrease in IQ scores in children prenatally exposed to the drug. For patients with migraine, the pregnancy labeling of VPA will be changed from Category "D" to "X." VPA products will remain in pregnancy category "D" for treating epilepsy and manic episodes associated with bipolar disorder. Thus, this article aims to assess (through a computerized Medline/PubMed search) the neurobehavioral teratogenicity of valproate monotherapy, in order to evaluate alternative regulatory decisions. Reviewed information suggests a detrimental impact of antenatal valproate exposure on the global child neurodevelopment. Affected areas include not just reduced IQ scores, but also behavioral problems and a potential increase in the risk for a future diagnosis of attention-deficit/hyperactivity disorder. An increased risk of developing autism-spectrum disorders has also been reported. Thus, in my opinion, VPA should be assigned definitively to the Category "X," independent of any considerations about its clinical indications, and should be strictly avoided during pregnancy, due to the demonstrated risk of both neurobehavioral and neurocognitive teratogenicity.