Neurodevelopmental effects of fetal antiepileptic drug exposure

The evolution of antiseizure medication therapy selection in adults: Is artificial intelligence -assisted antiseizure medication selection ready for prime time?

Antiseizure medications (ASMs) are the mainstay of symptomatic epilepsy treatment. The primary goal of pharmacotherapy with ASMs in epilepsy is to achieve complete seizure remission while minimizing therapy-related adverse events. Over the years, more ASMs have been introduced, with approximately 30 now in everyday use. With such a wide variety, much guidance is needed in choosing ASMs for initial therapy, subsequent replacement monotherapy, or adjunctive therapy. The specific ASMs are typically tailored by the patient's related factors, including epilepsy syndrome, age, sex, comorbidities, and ASM characteristics, including the spectrum of efficacy, pharmacokinetic properties, safety, and tolerability. Weighing these key clinical variables requires experience and expertise that may be limited. Furthermore, with this approach, patients may endure multiple trials of ineffective treatments before the most appropriate ASM is found. A more reliable way to predict response to different ASMs is needed so that the most effective and tolerated ASM can be selected. Soon, alternative approaches, such as deep machine learning (ML), could aid the individualized selection of the first and subsequent ASMs. The recognition of epilepsy as a network disorder and the integration of personalized epilepsy networks in future ML platforms can also facilitate the prediction of ASM response. Augmenting the conventional approach with artificial intelligence (AI) opens the door to personalized pharmacotherapy in epilepsy. However, more work is needed before these models are ready for primetime clinical practice.

Proposal for reference values for the developmental effects of valproate based on human data using a benchmark dose approach

Following accidental release of valproate into ambient air during manufacture at a French production site in 2018, concerns were raised for inhabitants of the surrounding area. As no toxicological reference value (TRV) was available, the risks could not be properly assessed. The French Agency for Food, Environmental and Occupational Health and Safety (ANSES) was mandated to determine a TRV by inhalation to be used for risk assessment. Major congenital malformations (MCMs) in offsprings of mothers exposed to valproate during pregnancy have been reported in international scientific literature. As these adverse effects were the most sensitive effect identified, they were retained as the critical effect to be used for the TRV. The data from a robust registry on MCMs established by the International Registry of Antiepileptic Drugs and Pregnancy (EURAP) were modellized and support a strong DRR between the prevalence of MCMs in the fetus and in utero exposure. A benchmark dose (BMD) was then calculated as the dose that may trigger a 5% increase in this risk. A lower 95% confidence limit (BMD5%L95%) of 2.26 mg/kg/day, leading to an oral TRV of 0.08 mg/kg/day and a respiratory TRV of 0.26 mg.m-3 after applying an uncertainty factor of 30, was determined.

Epilepsy Characteristics in Neurodevelopmental Disorders: Research from Patient Cohorts and Animal Models Focusing on Autism Spectrum Disorder

Epilepsy, a heterogeneous group of brain-related diseases, has continued to significantly burden society and families. Epilepsy comorbid with neurodevelopmental disorders (NDDs) is believed to occur due to multifaceted pathophysiological mechanisms involving disruptions in the excitation and inhibition (E/I) balance impeding widespread functional neuronal circuitry. Although the field has received much attention from the scientific community recently, the research has not yet translated into actionable therapeutics to completely cure epilepsy, particularly those comorbid with NDDs. In this review, we sought to elucidate the basic causes underlying epilepsy as well as those contributing to the association of epilepsy with NDDs. Comprehensive emphasis is put on some key neurodevelopmental genes implicated in epilepsy, such as MeCP2, SYNGAP1, FMR1, SHANK1-3 and TSC1, along with a few others, and the main electrophysiological and behavioral deficits are highlighted. For these genes, the progress made in developing appropriate and valid rodent models to accelerate basic research is also detailed. Further, we discuss the recent development in the therapeutic management of epilepsy and provide a briefing on the challenges and caveats in identifying and testing species-specific epilepsy models.

Integrative genomics reveals pathogenic mediator of valproate-induced neurodevelopmental disability

Prenatal exposure to the anti-seizure medication sodium valproate (VPA) is associated with an increased risk of adverse postnatal neurodevelopmental outcomes, including lowered intellectual ability, autism spectrum disorder and attention-deficit hyperactivity disorder. In this study, we aimed to clarify the molecular mechanisms underpinning the neurodevelopmental consequences of gestational VPA exposure using integrative genomics. We assessed the effect of gestational VPA on foetal brain gene expression using a validated rat model of valproate teratogenicity that mimics the human scenario of chronic oral valproate treatment during pregnancy at doses that are therapeutically relevant to the treatment of epilepsy. Two different rat strains were studied-inbred Genetic Absence Epilepsy Rats from Strasbourg, a model of genetic generalized epilepsy, and inbred non-epileptic control rats. Female rats were fed standard chow or VPA mixed in standard chow for 2 weeks prior to conception and then mated with same-strain males. In the VPA-exposed rats maternal oral treatment was continued throughout pregnancy. Foetuses were extracted via C-section on gestational Day 21 (1 day prior to birth) and foetal brains were snap-frozen and genome-wide gene expression data generated. We found that gestational VPA exposure via chronic maternal oral dosing was associated with substantial drug-induced differential gene expression in the pup brains, including dysregulated splicing, and observed that this occurred in the absence of evidence for significant neuronal gain or loss. The functional consequences of VPA-induced gene expression were explored using pathway analysis and integration with genetic risk data for psychiatric disease and behavioural traits. The set of genes downregulated by VPA in the pup brains were significantly enriched for pathways related to neurodevelopment and synaptic function and significantly enriched for heritability to human intelligence, schizophrenia and bipolar disorder. Our results provide a mechanistic link between chronic foetal VPA exposure and neurodevelopmental disability mediated by VPA-induced transcriptional dysregulation.

The Use of Antiepileptic Drugs During Pregnancy and Fetal Outcomes

Epilepsy affects approximately 1 percent of the population and roughly 1 million women of childbearing age. Estimates suggest that 0.3-0.7 percent of pregnancies occur in women with epilepsy. Epilepsy itself increases the risk of congenital malformation and medications add to this risk. Also, approximately one-half of the use of medications for epilepsy are used for other indications, possibly increasing exposure in some women. As controlled trials with these medications are not performed during pregnancy, data has been accumulated primarily through databases and case studies. This review is intended to update the practitioner about the use and concerns of antiepileptic medications in the presnant woman and the potential effects on the fetus and neonate.

Achieving neurologically desirable outcomes to pregnancy in women with epilepsy

OBJECTIVES

To investigate possible factors that influenced whether pregnancy in women with epilepsy resulted in the desirable outcome of a live-born non-malformed infant and a mother whose pregnancy had been seizure free.

RESULTS

The desirable outcome, as defined, occurred in 46.3% of unselected pregnancies in the database of the Australian Register of Antiepileptic Drugs in Pregnancy (APR). The only factor investigated that had a statistically significant (P < 0.05) effect, increasing the chance of such a desirable outcome, was freedom from seizures in the pre-pregnancy year. However, anti-seizure medication (ASM) doses, particularly valproate doses, had been reduced prior to 15.6% of the pregnancies, and this may have concealed factors that otherwise may have adversely affected the desirable outcome rate. Analysis of data for monotherapy with the more commonly used ASMs appears to suggest that employing levetiracetam at the outset of antiseizure therapy may offer a better chance of a desirable outcome to future pregnancies than monotherapy with other ASMs, but this finding is not confirmed statistically.

CONCLUSIONS

In pregnancies where valproate use has already been minimized, seizure control throughout the pre-pregnancy year was associated with the best chance of a desirable outcome, as defined above. In most Australian women starting therapy for epilepsy initiating treatment with levetiracetam monotherapy may offer the best chance of such a desirable outcome to a future pregnancy, yet to be confirmed.

Effect of levetiracetam on the gene expression of placental transporters in a murine model

OBJECTIVE

Levetiracetam (LEV) is an antiseizure medication prescribed to women during childbearing age. The impact of LEV on placental transporters is poorly understood. This study aimed to assess the effect of LEV exposure on the messenger RNA (mRNA) expression of placental transporters for hormones and nutrients and to correlate their expression with the drug's serum concentration in pregnant mice.

METHODS

Studies were conducted on gestational days (GD) 13 and 18, following oral treatment with 100 mg/kg LEV or the vehicle every 24 h after weaning. Serum LEV measurements were performed by High-performance liquid chromatography with a UV detector (HPLC-UV). The weight, height, and width of the fetuses were also analyzed. In addition, the placental expression of transporters xCt, Lat1, Oatp4a1, Fr-α, Rfc, and Snat4 was evaluated through semi-quantitative real-time polymerase chain reaction (qPCR). The Kruskal-Wallis and the Mann-Whitney U tests were used to determine the statistical significance (p < .05). The correlation between serum LEV concentration and placental gene expression was evaluated using the Spearman test.

RESULTS

The weight, height, and width were lower in the fetuses exposed to LEV compared with the control group (p < .05). The number of fetuses was lower in the LEV-exposed group than in the control GD 13 group (p < .001). No significant differences were detected in the mRNA expression level at GD 13. At GD 18, the expression of Lat1, Oatp4a1, xCT, and Snat4 was higher in the group treated with LEV compared with the control group (p < .05), whereas the expression of Rfc was lower (p < .05). No correlation was identified between serum LEV concentrations and gene expression levels.

SIGNIFICANCE

The repression of the Rfc transcript by LEV at GD 18 suggests that the protein expression would be abolished contributing to the observed intrauterine growth restriction (IUGR). Furthermore, the significant increase in mRNA of xCt, Snat4, Oatp4a1, and Lat1 might be a compensatory mechanism for fetal survival at GD 18.

Epilepsy and pregnancy: What should the neurologists do?

Epilepsy is one of the most common chronic disorders affecting women of childbearing age. Unfortunately, many women with epilepsy (WWE) still report not receiving key information about pregnancy. They obviously need information about epilepsy and pregnancy prior to conception with a particular emphasis on effective birth control (i.e. contraception), necessity to plan pregnancy, antiepileptic drugs optimization, and folate supplementation. The risks associated with use of antiepileptic drugs during pregnancy have to be balanced against fetal and maternal risks associated with uncontrolled seizures. This report reviews evidence-based counseling and management strategies concerning maternal and fetal risks associated with seizures, teratogenic risks associated with antiepileptic drug exposure with a special emphasis on developmental and behavioural outcomes of children exposed to intra utero antiepileptic drugs.

Psychiatric comorbidities, sexual health and neurodevelopmental outcomes of offspring in men with epilepsy

BACKGROUND

There is a paucity of data in the literature specific to men with epilepsy on anti-seizure medication (ASM). The current study investigated the time to conception as well as the gestational and the neurodevelopmental outcomes of offspring of men with epilepsy on ASM compared to controls. Additionally, the prevalence of psychiatric comorbidities, and measures of sexual performance in males with and without epilepsy were analyzed.

METHODS

A total of 450 male patients with and without epilepsy at one hospital were provided questionnaires to determine demographic characteristics, epilepsy history, type of ASM at the time of conception, comorbidities and sexual health. Time to conception, fertility methods and offspring birth and developmental history born to males with and without epilepsy was recorded. Survey data was evaluated using Student's t-test for continuous variables and Fisher's exact test for categorical variables. Odds ratio (OR) were calculated to determine associations between the measured data.

RESULTS

After matching for age, we analyzed a total of 110 males with epilepsy and 110 without epilepsy. In the epilepsy group there was a higher rate of psychiatric comorbidities such as major depressive disorder, general anxiety disorder, bipolar disorder, and suicidal ideation when compared to the control group (N = 110; OR 3.39; 95% IC: 1.87-6.13, p < 0.001). Males with epilepsy also had a higher frequency of low erection scores when compared to males without epilepsy (N = 70 with epilepsy, N = 76 without epilepsy; OR 3.67; 95% IC: 1.44-9.39, p = 0.005). Of the 110 men with a diagnosis of epilepsy, 17 conceived children while using ASMs (38 total children). A total of 18.42% of children born to fathers on ASMs experienced developmental delays compared to 2.63% of controls, however this result was not statistically significant (p = 0.056). In addition, we did not find that offspring had significantly different birth weights or gestational ages in men on ASM compared to controls (p > 0.05).

CONCLUSIONS

The present study suggests that men with epilepsy have an increased incidence of psychiatric comorbidities, and altered sexual performance, specifically erectile dysfunction, when compared with men without epilepsy. There was no statistically significant difference in the rates of developmental disorders and birth characteristics among those men with epilepsy on ASM at the time of conception and controls.

On the Digital Psychopharmacology of Valproic Acid in Mice

Antiepileptic drugs (AEDs) require daily ingestion for maximal seizure prophylaxis. Adverse psychiatric consequences of AEDs present as: (i) reversible changes in mood, anxiety, anger and/or irritability that often necessitate drug discontinuation, and (ii) autism and/or cognitive/psychomotor delays following fetal exposure. Technical advances in quantifying naturalistic rodent behaviors may provide sensitive preclinical estimates of AED psychiatric tolerability and neuropsychiatric teratogenicity. In this study, we applied instrumented home-cage monitoring to assess how valproic acid (VPA, dissolved in sweetened drinking water) alters home-cage behavior in adult C57BL/6J mice and in the adult offspring of VPA-exposed breeder pairs. Through a pup open field assay, we also examined how prenatal VPA exposure impacts early spontaneous exploratory behavior. At 500-600 mg/kg/d, chronic VPA produced hyperphagia and increased wheel-running without impacting sleep, activity and measures of risk aversion. When applied to breeder pairs of mice throughout gestation, VPA prolonged the latency to viable litters without affecting litter size. Two-weeks old VPA-exposed pups displayed open field hypoactivity without alterations in thigmotaxis. As adults, prenatal VPA-exposed mice displayed active state fragmentation, hypophagia and increased wheel running, together with subtle alterations in home-cage dyadic behavior. Together, these data illustrate how automated home-cage assessments of spontaneous behavior capture an ethologically centered psychopharmacological profile of enterally administered VPA that is aligned with human clinical experience. By characterizing the effects of pangestational VPA exposure, we discover novel murine expressions of pervasive neurodevelopment. Incorporating such rigorous assessments of psychological tolerability may inform the design of future AEDs with improved neuropsychiatric safety profiles, both for patients and their offspring.

Association of Prenatal Exposure to Valproate and Other Antiepileptic Drugs With Intellectual Disability and Delayed Childhood Milestones

Importance

There is concern about neurodevelopmental outcomes associated with prenatal exposure to valproate and other antiepileptic drugs (AEDs) among children of mothers with or without epilepsy.

Objective

To study the risk of intellectual disability and delayed development in childhood milestones among children of women who used valproate or other AEDs during pregnancy.

Design, Setting, and Participants

This population-based cohort study analyzed information on use of AEDs from the Danish National Prescription Registry and register diagnoses from the Danish Psychiatric Central Research Register and Danish National Patient Registry. The study included all live-born singletons in Denmark from January 1, 1997, to December 31, 2011. Data were analyzed in April 2020.

Exposures

Prenatal exposure to maternal valproate and other AEDs.

Main Outcomes and Measures

The main measures were adjusted Cox regression estimates of hazard ratios (aHRs) for intellectual disability and a combined outcome of intellectual disability with delayed childhood milestones.

Results

A total of 913 302 children (468 708 [51.3%] boys; mean [SD] age, 10.3 [4.4] years and median [interquartile range] age, 10.1 [6.5-14.0] years at final follow-up) were identified and contributed more than 10.2 million person-years of observation, including 580 children exposed to valproate (302 [51.3%] boys). At end of follow-up, 6958 children (0.8%) were identified as having intellectual disability and 14 967 children (1.6%) were identified as having intellectual disability with delayed childhood milestones. Compared with offspring not exposed to valproate prenatally, offspring of women who used valproate during pregnancy had increased risk of intellectual disability (aHR, 4.48; 95% CI, 2.97-6.76) and intellectual disability with delayed childhood milestones (aHR, 6.07; 95% CI, 4.67-7.89). Among mothers with epilepsy, offspring exposed prenatally to valproate had increased risk of intellectual disability (aHR, 1.95; 95% CI, 1.21-3.14) and intellectual disability with delayed childhood milestones (aHR, 3.07; 95% CI, 2.24-4.20) compared with offspring without prenatal exposure. Compared with offspring without prenatal exposure to AEDs, increased risk of intellectual disability was identified in children with prenatal exposure to maternal monotherapy use of carbamazepine (aHR, 3.84; 95% CI, 2.32-6.38), clonazepam (aHR, 2.41; 95% CI, 1.09-5.35), and oxcarbazepine (aHR, 3.70; 95% CI, 2.11-6.51) but not lamotrigine (aHR, 1.33; 95% CI, 0.71-2.48).

Conclusions and Relevance

These findings suggest that prenatal exposure to valproate was associated with increased risk of intellectual disability and delayed childhood milestones. Statistically significant associations were also found for prenatal exposure to other AEDs. These findings suggest that women of childbearing potential may need to be counseled on use of AEDs.

Prenatal exposure to oxcarbazepine increases hippocampal apoptosis in rat offspring

This study assessed apoptosis in the offspring of rats exposed to oxcarbazepine (OXC) from day 7 to 15 of gestation. Three groups of pregnant Wistar rats were used: 1) Control, treated with saline solution; 2) treated with 100 mg/kg OXC; 3) treated with 100 mg/kg of carbamazepine (CBZ, as a positive control for apoptosis); the route of administration was intragastric. Apoptosis was detected at three postnatal ages using the TUNEL technique in the CA1, and CA3 regions of the hippocampus and in the dentate gyrus (DG); neurogenesis was assessed in the DG using an antibody against doublecortin. The litter characteristics were recorded. OXC increased apoptosis in all regions (p < 0.01) at the three ages evaluated. Lamination disruption occurred in CA1 and CA3 due to the neuron absence and to ectopic neurons; there were also malformations in the dorsal lamina of the DG in 38% and 25% of the pups born from rats treated with OXC and CBZ respectively. CBZ also increased apoptosis. No clear effect on neurogenesis in the DG was observed. The size of the litter was smaller (p < 0.01) in the experimental groups. Nineteen-day OXC fetuses had low weight (p < 0.01), but 21 and 30 postnatal days old CBZ and OXC pups were overweight (p < 0.01). The results demonstrate that OXC administered during gestation is pro-apoptotic, alters the cytoarchitecture of the hippocampus, reduces litter size, and probably influences postnatal weight. We provide evidence of the proapoptotic effect of CBZ when administered early in gestation.

Assembling systems biology, embryo development and teratogenesis: What do we know so far and where to go next?

The recognition of molecular mechanisms of a teratogen can provide insights to understand its embryopathy, and later to plan strategies for the prevention of new exposures. In this context, experimental research is the most invested approach. Despite its relevance, these assays require financial and time investment. Hence, the evaluation of such mechanisms through systems biology rise as an alternative for this conventional methodology. Systems biology is an integrative field that connects experimental and computational analyses, assembling interaction networks between genes, proteins, and even teratogens. It is a valid strategy to generate new hypotheses, that can later be confirmed in experimental assays. Here, we present a literature review of the application of systems biology in embryo development and teratogenesis studies. We provide a glance at the data available in public databases, and evaluate common mechanisms between different teratogens. Finally, we discuss the advantages of using this strategy in future teratogenesis researches.

Treatment of early life status epilepticus: What can we learn from animal models?

Treatment of status epilepticus (SE) in infants and children is challenging. There is a recognition that a broad set of developmental processes need to be considered to fully appreciate the physiologic complexity of severe seizures, and seizure outcomes, in infants and children. The development and use of basic models to elucidate important mechanisms will help further our understanding of these processes. Here we review some of the key experimental models and consider several areas relevant to treatment that could lead to productive translational research. Terminating seizures quickly is essential. Understanding pharmacoresistance of SE as it relates to receptor trafficking will be critical to seizure termination. Once a severe seizure is terminated, how will the developing brain respond? Basic studies suggest that there are important acute and long‐term histopathologic, and pathophysiologic, consequences that, if left unaddressed, will produce long‐lasting deficits on the form and function of the central nervous system. To fully utilize the evidence that basic models produce, age‐ and development‐ and model‐specific frameworks have to be considered carefully. Studies have demonstrated that severe seizures can cause perturbations to developmental processes during critical periods of development that lead to life‐long deficits. Unfortunately, some of the drugs that are commonly used to treat seizures may also produce negative outcomes by enhancing Cl^‐‐mediated depolarization, or by accelerating programmed cell death. More research is needed to understand these phenomena and their relevance to the human condition, and to develop rational drugs that protect the developing brain from severe seizures to the fullest extent possible.

Emilia-Romagna Study on Pregnancy and Exposure to Antiepileptic drugs (ESPEA): a population-based study on prescription patterns, pregnancy outcomes and fetal health

OBJECTIVES

To assess the prevalence of antiepileptic drug (AED) exposure in pregnant women and the comparative risk of terminations of pregnancy (TOPs), spontaneous abortions, stillbirths, major birth defects (MBDs), neonatal distress and small for gestational age (SGA) infants following intrauterine AED exposure in the Emilia Romagna region, Italy (4 459 246 inhabitants on 31 December 2011).

METHODS

We identified all deliveries and hospitalised abortions in Emilia Romagna in the period 2009-2011 from the certificate of delivery assistance registry (Certificato di Assistenza al Parto- CedAP) and the hospital discharge card registry, exposure to AEDs from the reimbursed drug prescription registries, MBDs from the regional registry of congenital malformations, and Apgar scores and cases of SGA from the CedAP. Records from different registries were linked.

RESULTS

We identified 145 243 pregnancies: 111 284 deliveries, 16 408 spontaneous abortions and 17 551 TOPs. Six hundred and eleven pregnancies (0.42%; 95% Cl 0.39 to 0.46) were exposed to AEDs. In the AED-exposed group 21% of pregnancies ended in TOPs vs 12% in the non-exposed women (OR: 2.24; 95% CI 1.41 to 3.56). Rates of spontaneous abortions, stillbirths, neonatal distress and SGA were comparable. Three hundred and fifty-three babies (0.31%; 95% CI 0.28 to 0.35) were exposed to AEDs during the first trimester. MBD rates were 2.3% in the exposed vs 2.0% in the non-exposed pregnancies (OR: 1.12, 95% CI 0.55 to 2.55).

CONCLUSION

The Emilia Romagna prevalence of AED exposure in pregnancy was 0.42%, comparable with previous European studies. Rates of spontaneous abortions, stillbirths, neonatal distress, SGA and MBDs following AED exposure were not significantly increased. The rate of TOPs was significantly higher in the AED-exposed women.

Verbal abilities in children of mothers with epilepsy: Association to maternal folate status

Objective

To examine the effect of maternal folic acid supplementation and maternal plasma folate and antiepileptic drug (AED) concentrations on language delay in AED-exposed children of mothers with epilepsy.

Methods

Children of mothers with and without epilepsy enrolled from 1999 to 2008 in the Norwegian Mother and Child Cohort study were included. Information on medical history, AED use, and folic acid supplementation during pregnancy was collected from parent-completed questionnaires. Maternal plasma folate and maternal plasma and umbilical cord AED concentrations were measured in blood samples from gestational weeks 17 to 19 and immediately after birth, respectively. Language development at 18 and 36 months was evaluated by the Ages and Stages Questionnaires.

Results

A total of 335 AED-exposed children of mothers with epilepsy and 104,222 children of mothers without epilepsy were surveyed. For those with no maternal periconceptional folic acid supplementation, the fully adjusted odds ratio (OR) for language delay in AED-exposed children compared to the controls at 18 months was 3.9 (95% confidence interval [CI] 1.9–7.8, p < 0.001) and at 36 months was 4.7 (95% CI 2.0–10.6, p < 0.001). When folic supplementation was used, the corresponding ORs for language delay were 1.7 (95% CI 1.2–2.6, p = 0.01) and 1.7 (95% CI 0.9–3.2, p = 0.13), respectively. The positive effect of folic acid supplement use on language delay in AED-exposed children was significant only when supplement was used in the period from 4 weeks before the pregnancy and until the end of the first trimester.

Conclusion

Folic acid use early in pregnancy may have a preventive effect on language delay associated with in utero AED exposure.

Turing Revisited: Decoding the microRNA Messages in Brain Extracellular Vesicles for Early Detection of Neurodevelopmental Disorders

The prevention of neurodevelopmental disorders (NDD) of prenatal origin suffers from the lack of objective tools for early detection of susceptible individuals and the long time lag, usually in years, between the neurotoxic exposure and the diagnosis of mental dysfunction. Human data on the effects of alcohol, lead, and mercury and experimental data from animals on developmental neurotoxins and their long-term behavioral effects have achieved a critical mass, leading to the concept of the Developmental Origin of Health and Disease (DOHaD). However, there is currently no way to evaluate the degree of brain damage early after birth. We propose that extracellular vesicles (EVs) and particularly exosomes, released by brain cells into the fetal blood, may offer us a non-invasive means of assessing brain damage by neurotoxins. We are inspired by the strategy applied by Alan Turing (a cryptanalyst working for the British government), who created a first computer to decrypt German intelligence communications during World War II. Given the growing evidence that microRNAs (miRNAs), which are among the molecules carried by EVs, are involved in cell-cell communication, we propose that decrypting messages from EVs can allow us to detect damage thus offering an opportunity to cure, reverse, or prevent the development of NDD. This review summarizes recent findings on miRNAs associated with selected environmental toxicants known to be involved in the pathophysiology of NDD.

Parental psychopathology and offspring attention-deficit/hyperactivity disorder in a nationwide sample

OBJECTIVE

To study the associations between a wide range of parental psychiatric disorders and offspring attention-deficit/hyperactivity disorder (ADHD).

METHOD

This study is based on a nested case-control design. The association between parental registered psychiatric diagnoses and offspring ADHD was examined adjusting for socioeconomic and prenatal factors. Data was linked from Finnish nationwide registers. The cases (n = 10,409) were all the children born between years 1991 and 2005 in Finland and diagnosed with ADHD by the end of 2011. Four controls without ADHD (n = 39,124) were matched for every case by sex, age and place of birth. Main outcomes were adjusted odds ratio (aOR) for parental diagnosis of cases vs controls. Analyses were further stratified by sex. Disorders diagnosed before and after birth were analyzed separately.

RESULTS

The odds ratio for ADHD increased when only mother (aOR 2.2, 95% CI 2.0-2.3), only father (aOR 1.7, 95% CI 1.6-1.8) and both parents (aOR 3.6, 95% CI 3.3-4.0) were diagnosed. Maternal diagnosis showed stronger association than paternal. The weight of association between several parental disorders and offspring ADHD were similar. Maternal psychopathology overall showed stronger associations with girls than boys with ADHD. The diagnoses registered after birth did not show stronger association than the diagnoses registered before.

CONCLUSIONS

Maternal psychopathology showing stronger association than paternal implies that environmental factors or their interaction with genetic factors partly mediates the risk of parental psychopathology. Similar associations between several maternal psychiatric disorders and offspring ADHD points towards the need for investigating some common mother-related risk factors.

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).

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.

Prenatal exposure to antiepileptic drugs and use of primary healthcare during childhood: a population-based cohort study in Denmark

OBJECTIVE

Prenatal exposure to antiepileptic drugs (AEDs) has been associated with adverse outcomes in the offspring such as congenital malformations and neuropsychiatric disorders. The objective of this study was to investigate whether prenatal exposure to AEDs is also associated with more frequent use of primary healthcare during childhood.

DESIGN

Population-based cohort study.

SETTING

Nationwide national registers in Denmark.

PARTICIPANTS

All live-born singletons in Denmark during 1997-2012 identified in the Danish National Patient Register and followed until 31 December 2013 (n=963 010). Information on prenatal exposure to AEDs for maternal indication of epilepsy and other neurological conditions was obtained from the Danish Register of Medicinal Product Statistics.

MAIN OUTCOME MEASURES

The primary outcome measure was the number and type of contacts with the general practitioner (GP), excluding routine well-child visits and vaccinations. The secondary outcome measure was specific services provided at the GP contact. The association between prenatal exposure to AEDs and contacts with the GP was estimated by using negative binomial regression adjusting for sex and date of birth of the child, maternal age, cohabitation status, income, education, substance abuse, depression, severe psychiatric disorders and use of antipsychotics, antidepressants and insulin.

RESULTS

Children exposed prenatally to AEDs (n=4478) had 3% (95% CI 0 to 5%) more GP contacts during the study period than unexposed children. This was primarily accounted for by the number of phone contacts. Within each year of follow-up, exposed children tended to have more contacts than unexposed children, but the differences were small. We found no difference between exposed and unexposed children with regard to specific services provided at the GP contact. For the individual AEDs, we found that exposure to valproate or oxcarbazepine was associated with more GP contacts.

CONCLUSIONS

We found only minor differences between prenatally AED-exposed and unexposed children in the number of GP contacts.

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

INTRODUCTION

Prenatal antiepileptic drug (AED) exposure is associated with an increased risk of cognitive impairment and autism spectrum disorders detected mainly at the age of two to six years. We examined whether the developmental aberrations associated with prenatal AED exposure could be detected already in infancy and whether effects on visual attention can be observed at this early age.

MATERIAL AND METHODS

We compared a prospective cohort of infants with in utero exposure to AED (n=56) with infants without drug exposures (n=62). The assessments performed at the age of seven months included standardized neurodevelopmental scores (Griffiths Mental Developmental Scale and Hammersmith Infant Neurological Examination) as well as a novel eye-tracking-based test for visual attention and orienting to faces. Background information included prospective collection of AED exposure data, pregnancy outcome, neuropsychological evaluation of the mothers, and information on maternal epilepsy type.

RESULTS

Carbamazepine, oxcarbazepine, and valproate, but not lamotrigine or levetiracetam, were associated with impaired early language abilities at the age of seven months. The general speed of visuospatial orienting or attentional bias for faces measured by eye-tracker-based tests did not differ between AED-exposed and control infants.

DISCUSSION

Our findings support the idea that prenatal AED exposure may impair verbal abilities, and this effect may be detected already in infancy. In contrast, the early development of attention to faces was spared after in utero AED exposure.

High-dose versus low-dose valproate for the treatment of juvenile myoclonic epilepsy: Going from low to high

Juvenile myoclonic epilepsy (JME) is a genetic generalized epilepsy accounting for 3-12% of adult cases of epilepsy. Valproate has proven to be the first-choice drug in JME for controlling the most common seizure types: myoclonic, absence, and generalized tonic-clonic (GTC). In this retrospective study, we analyzed seizure outcome in patients with JME using valproate monotherapy for a minimum period of one year. Low valproate dose was considered to be 1000mg/day or lower, while serum levels were considered to be low if they were at or below 50mcg/dl. One hundred three patients met the inclusion criteria. Fifty-six patients (54.4%) were female. The current average age was 28.4±7.4years, while the age of epilepsy onset was 13.6±2.9years. Most patients corresponded to the subsyndrome of classic JME. Forty-six (44.7%) patients were free from all seizure types, and 76 (73.7%) patients were free from GTC seizures. No significant difference was found in seizure freedom among patients using a low dose of valproate versus a high dose (p=0.535) or among patients with low blood levels versus high blood levels (p=0.69). In patients with JME, it seems appropriate to use low doses of valproate (500mg to 1000mg) for initial treatment and then to determine if freedom from seizures was attained.

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.

Management of adverse effects of mood stabilizers

Mood stabilizers such as lithium and anticonvulsants are still standard-of-care for the acute and long-term treatment of bipolar disorder (BD). This systematic review aimed to assess the prevalence of their adverse effects (AEs) and to provide recommendations on their clinical management. We performed a systematic research for studies reporting the prevalence of AEs with lithium, valproate, lamotrigine, and carbamazepine/oxcarbazepine. Management recommendations were then developed. Mood stabilizers have different tolerability profiles and are eventually associated to cognitive, dermatological, endocrine, gastrointestinal, immunological, metabolic, nephrogenic, neurologic, sexual, and teratogenic AEs. Most of those can be transient or dose-related and can be managed by optimizing drug doses to the lowest effective dose. Some rare AEs can be serious and potentially lethal, and require abrupt discontinuation of medication. Integrated medical attention is warranted for complex somatic AEs. Functional remediation and psychoeducation may help to promote awareness on BD and better medication management.