Teratogenic effects of antiepileptic drugs

Valproic acid after five decades of use in epilepsy: time to reconsider the indications of a time-honoured drug

Since the serendipitous discovery of its anticonvulsant properties more than 50 years ago, valproic acid has become established as an effective broad-spectrum antiepileptic drug that is particularly useful for the management of generalised epilepsies, for which treatment alternatives are few. However, during the past few years increasing evidence has accumulated that intake of valproic acid during pregnancy is associated with a significant risk of dose-dependent teratogenic effects and impaired postnatal cognitive development in children. Because of these risks, valproic acid should not be used as a first-line drug in women of childbearing potential whenever equally or more effective alternative drugs are available-as in the case of focal epilepsy. In some generalised epilepsy syndromes, such as juvenile myoclonic epilepsy, valproic acid has better documented efficacy than alternative drugs and drug selection should be a shared decision between the clinician and the informed patient based on careful risk-benefit assessment.

Developmental effects of antiepileptic drugs and the need for improved regulations

Antiepileptic drugs (AEDs) are among the most common teratogenic drugs prescribed to women of childbearing age. AEDs can induce both anatomical (malformations) and behavioral (cognitive/behavioral deficits) teratogenicity. Only in the last decade have we begun to truly discriminate differential AED developmental effects. Fetal valproate exposure carries a special risk for both anatomical and behavioral teratogenic abnormalities, but the mechanisms and reasons for individual variability are unknown. Intermediate anatomical risks exist for phenobarbital and topiramate. Several AEDs (e.g., lamotrigine and levetiracetam) appear to possess low risks for both anatomical and behavioral teratogenesis. Despite advances in the past decade, our knowledge of the teratogenic risks for most AEDs and the underlying mechanisms remain inadequate. Further, the long-term effects of AEDs in neonates and older children remain uncertain. The pace of progress is slow given the lifelong consequences of diminished developmental outcomes, exposing children unnecessarily to potential adverse effects. It is imperative that new approaches be employed to determine risks more expediently. Our recommendations include a national reporting system for congenital malformations, federal funding of the North American AED Pregnancy Registry, routine meta-analyses of cohort studies to detect teratogenic signals, monitoring of AED prescription practices for women, routine preclinical testing of all new AEDs for neurodevelopmental effects, more specific Food and Drug Administration requirements to establish differential AED cognitive effects in children, and improved funding of basic and clinical research to fully delineate risks and underlying mechanisms for AED-induced anatomical and behavioral teratogenesis.

Management of epilepsy during pregnancy

Over a million women with epilepsy are of childbearing age in the USA and require careful consideration of not only type of antiepileptic drug (AED) but also dosage, in the event of a planned or unplanned pregnancy. Careful selection of AEDs can lower the potential adverse effects of AEDs while maintaining seizure control for the health of not only on the patient, the mother, but also the unborn fetus. The number of treatment options has increased significantly in the last 20 years and remarkable progress has been made in characterizing the risks AEDs pose to pregnant women and fetuses. There are now robust data on teratogenesis, a growing body of data on neonatal/obstetrical outcomes and on neurodevelopmental problems associated with each AED, and some data about seizure control during pregnancy. Based on clinical evidence so far, levetiracetam and lamotrigine have emerged as the safest during pregnancy, although others may also be suitable. Despite being a common belief, not all polytherapy combinations may be detrimental, especially when avoiding valproate and topiramate. Here, we review the available clinical research, highlighting recent findings and provide thoughts for future directions in the field.

Changes in the Peripheral Blood Gene Expression Profile Induced by 3 Months of Valproate Treatment in Patients with Newly Diagnosed Epilepsy

Valproic acid (VPA) is a widely used antiepileptic drug with a broad range of effects and broad clinical efficacy. As a well-known histone deacetylase (HDAC) inhibitor, VPA regulates epigenetic programming by altering the expression of many genes. The aim of study was to analyze differences in gene expression profiles before and after the start of VPA treatment in patients with newly diagnosed epilepsy. RNA sequencing was used to compare whole-genome gene expression patterns of peripheral blood from nine patients with epilepsy before and 3 months after the start of treatment with VPA. Of the 23,099 analyzed genes, only 11 showed statistically significant differential expression with false discovery rate-adjusted p-values below 0.1. Functional annotation and network analyses showed activation of only one genetic network (enrichment score = 30), which included genes for cardiovascular system development and function, cell morphology, and hematological system development and function. The finding of such a small number of differently expressed genes between before and after the start of treatment suggests a lack of HDAC inhibition in these patients, which could be explained by the relatively low doses of VPA that were used. In conclusion, VPA at standard therapeutic dosages modulates the expression of a small number of genes. Therefore, to minimize the potential side effects of HDAC inhibition, it is recommended that the lowest effective dose of VPA be used for treating epilepsy.

Aortopulmonary collateral artery in prenatal exposure to carbamazepine - endovascular therapy and technical considerations: a case report

INTRODUCTION

Aortopulmonary collateral arteries are an uncommon variant of alternative blood supply in cases of complex congenital heart disease. Although surgery may still be the classic approach for this condition, mini-invasive endovascular occlusion has been recently attempted as an alternative less traumatic procedure. Children born to women with epilepsy are at increased risk of congenital malformations.

CASE PRESENTATION

A cardiovascular malformation in a 6-year-old white boy with prenatal exposure to carbamazepine is described. At birth, he underwent atrial-ventricular septal defects repair. At 6 years of age, he was diagnosed to have an aberrant aortopulmonary artery from the descending aorta. He presented with recurrent respiratory infections and no cardiovascular signs, but there was associated right upper lobe hyperperfusion. Collateral percutaneous plug embolization was performed because of risk for cardiorespiratory infections, pulmonary hypertension and atrioventricular dilatation. The post-releasing control showed a complete occlusion of the aberrant artery. A chest radiogram and computed tomography showed normalization of vascular pattern of his right lung at 9-months follow-up. No complications and no respiratory infections in the first follow-up year were observed. A good growth gain was obtained.

CONCLUSIONS

Plug embolization in an aortopulmonary collateral artery is an interesting alternative to surgery and is suitable for children with minor congenital heart disease and without severe respiratory and/or cardiovascular symptoms. Management and long-term pediatric multidisciplinary follow-up is recommended. Prenatal exposure to carbamazepine could be considered in the pathogenesis and diagnosis of the malformation.

Valproate in the treatment of epilepsy in girls and women of childbearing potential

This document provides guidance on the use of valproate in girls and women of childbearing age from a joint Task Force of the Commission on European Affairs of the International League Against Epilepsy (CEA-ILAE) and the European Academy of Neurology (EAN), following strengthened warnings from the Coordination Group for Mutual Recognition and Decentralised Procedures-Human (CMDh) of the European Medicines Agency (EMA), which highlight the risk of malformations and developmental problems in infants who are exposed to valproate in the womb. To produce these recommendations, the Task Force has considered teratogenic risks associated with use of valproate and treatment alternatives, the importance of seizure control and of patient and fetal risks with seizures, and the effectiveness of valproate and treatment alternatives in the treatment of different epilepsies. The Task Force's recommendations include the following: (1) Where possible, valproate should be avoided in women of childbearing potential. (2) The choice of treatment for girls and women of childbearing potential should be based on a shared decision between clinician and patient, and where appropriate, the patient's representatives. Discussions should include a careful risk-benefit assessment of reasonable treatment options for the patient's seizure or epilepsy type. (3) For seizure (or epilepsy) types where valproate is the most effective treatment, the risks and benefits of valproate and other treatment alternatives should be discussed. (4) Valproate should not be prescribed as a first-line treatment for focal epilepsy. (5) Valproate may be offered as a first-line treatment for epilepsy syndromes where it is the most effective treatment, including idiopathic (genetic) generalized syndromes associated with tonic-clonic seizures. (6) Valproate may be offered as a first-line treatment in situations where pregnancy is highly unlikely (e.g., significant intellectual or physical disability). (7) Women and girls taking valproate require regular follow-up for ongoing consideration of the most appropriate treatment regimen.

Models of cortical malformation--Chemical and physical

Pharmaco-resistant epilepsies, and also some neuropsychiatric disorders, are often associated with malformations in hippocampal and neocortical structures. The mechanisms leading to these cortical malformations causing an imbalance between the excitatory and inhibitory system are largely unknown. Animal models using chemical or physical manipulations reproduce different human pathologies by interfering with cell generation and neuronal migration. The model of in utero injection of methylazoxymethanol (MAM) acetate mimics periventricular nodular heterotopia. The freeze lesion model reproduces (poly)microgyria, focal heterotopia and schizencephaly. The in utero irradiation model causes microgyria and heterotopia. Intraperitoneal injections of carmustine 1-3-bis-chloroethyl-nitrosurea (BCNU) to pregnant rats produces laminar disorganization, heterotopias and cytomegalic neurons. The ibotenic acid model induces focal cortical malformations, which resemble human microgyria and ulegyria. Cortical dysplasia can be also observed following prenatal exposure to ethanol, cocaine or antiepileptic drugs. All these models of cortical malformations are characterized by a pronounced hyperexcitability, few of them also produce spontaneous epileptic seizures. This dysfunction results from an impairment in GABAergic inhibition and/or an increase in glutamatergic synaptic transmission. The cortical region initiating or contributing to this hyperexcitability may not necessarily correspond to the site of the focal malformation. In some models wide-spread molecular and functional changes can be observed in remote regions of the brain, where they cause pathophysiological activities. This paper gives an overview on different animal models of cortical malformations, which are mostly used in rodents and which mimic the pathology and to some extent the pathophysiology of neuronal migration disorders associated with epilepsy in humans.

Oxcarbazepine-loaded polymeric nanoparticles: development and permeability studies across in vitro models of the blood-brain barrier and human placental trophoblast

Encapsulation of antiepileptic drugs (AEDs) into nanoparticles may offer promise for treating pregnant women with epilepsy by improving brain delivery and limiting the transplacental permeability of AEDs to avoid fetal exposure and its consequent undesirable adverse effects. Oxcarbazepine-loaded nanoparticles were prepared by a modified solvent displacement method from biocompatible polymers (poly(lactic-co-glycolic acid) [PLGA] with or without surfactant and PEGylated PLGA [Resomer^® RGPd5055]). The physical properties of the developed nanoparticles were determined with subsequent evaluation of their permeability across in vitro models of the blood–brain barrier (hCMEC/D3 cells) and human placental trophoblast cells (BeWo b30 cells). Oxcarbazepine-loaded nanoparticles with encapsulation efficiency above 69% were prepared with sizes ranging from 140–170 nm, polydispersity indices below 0.3, and zeta potential values below -34 mV. Differential scanning calorimetry and X-ray diffraction studies confirmed the amorphous state of the nanoencapsulated drug. The apparent permeability (P_e) values of the free and nanoencapsulated oxcarbazepine were comparable across both cell types, likely due to rapid drug release kinetics. Transport studies using fluorescently-labeled nanoparticles (loaded with coumarin-6) demonstrated increased permeability of surfactant-coated nanoparticles. Future developments in enzyme-prodrug therapy and targeted delivery are expected to provide improved options for pregnant patients with epilepsy.

Management of epilepsy during pregnancy: evidence-based strategies

Child-bearing years are often the most precarious management period in the life of a woman with epilepsy. This article reviews the results of many different studies with findings that enable the healthcare team to make confident decisions and recommendations during these critical periods. Preconceptional planning, effective contraception and folic acid supplementation are important fundamentals in preparation for pregnancy. There is growing evidence to avoid valproic acid use during the child-bearing years. Emerging data on congenital malformations and neurocognitive outcomes are available for some of the second-generation antiepileptic drugs and appear reassuring for lamotrigine and levetiracetam. Also reviewed are the benefits of postpartum drug tapers and favorable breastfeeding facts. Counseling the mother and her family on medication choices enables the healthcare team to implement informed decisions that are beneficial for the mother and child.

Perinatal Influences of Valproate on Brain and Behaviour: An Animal Model for Autism

Valproic acid or valproate (VPA) is an anti-convulsant and mood stabiliser effective in treating epilepsy and bipolar disorders. Although in adults VPA is well tolerated and safe, there is convincing evidence that it has teratogenic properties, ranging from mild neurodevelopmental changes to severe congenital malformations. In particular, studies involving humans and other animals have shown that prenatal exposure to VPA can induce developmental abnormalities reminiscent of autism spectrum disorder (ASD). In this chapter, we discuss the connection between VPA and ASD, evaluate the VPA animal model of ASD, and describe the possible molecular mechanisms underlying VPA's teratogenic properties.

Treatment of bipolar disorders during pregnancy: maternal and fetal safety and challenges

Treating pregnant women with bipolar disorder is among the most challenging clinical endeavors. Patients and clinicians are faced with difficult choices at every turn, and no approach is without risk. Stopping effective pharmacotherapy during pregnancy exposes the patient and her baby to potential harms related to bipolar relapses and residual mood symptom-related dysfunction. Continuing effective pharmacotherapy during pregnancy may prevent these occurrences for many; however, some of the most effective pharmacotherapies (such as valproate) have been associated with the occurrence of congenital malformations or other adverse neonatal effects in offspring. Very little is known about the reproductive safety profile and clinical effectiveness of atypical antipsychotic drugs when used to treat bipolar disorder during pregnancy. In this paper, we provide a clinically focused review of the available information on potential maternal and fetal risks of untreated or undertreated maternal bipolar disorder during pregnancy, the effectiveness of interventions for bipolar disorder management during pregnancy, and potential obstetric, fetal, and neonatal risks associated with core foundational pharmacotherapies for bipolar disorder.

The teratogenicity of the newer antiepileptic drugs - an update

OBJECTIVE

To assess the risk of teratogenicity from maternal intake of the more widely used newer antiepileptic drugs, especially lamotrigine, levetiracetam and topiramate.

MATERIALS AND METHODS

Use of confidence interval and regression methods to compare risks of foetal malformation in pregnancies in women exposed (n = 1572) and in women with epilepsy not exposed (n = 153) to antiepileptic drugs in the first trimester.

RESULTS

Compared with the foetal malformation rate in women with epilepsy who were untreated in the first trimester (3.3%), the malformation rates for lamotrigine (4.6%), levetiracetam (2.4%) and topiramate (2.4%), all in monotherapy, were not statistically significantly different. However, the malformation rates for topiramate as part of polytherapy (14.1%) and for valproate in both monotherapy (13.8%) and polytherapy (10.2%) were statistically significantly higher. Regression analysis of combined monotherapy and polytherapy data showed no statistically significant increased risk of teratogenesis associated with lamotrigine or levetiracetam, but a statistically significant and dose-related risk for first trimester topiramate (P = 0.01) and valproate (P < 0.0001) exposure.

CONCLUSIONS

Evidence from this and other studies suggests that lamotrigine and levetiracetam have low risk for teratogenesis, but that topiramate exposure early in pregnancy may be associated with dose-related anatomical teratogenesis, as valproate is already known to be.

Pharmacogenetic evaluation of ABCB1, Cyp2C9, Cyp2C19 and methylene tetrahydrofolate reductase polymorphisms in teratogenicity of anti-epileptic drugs in women with epilepsy

Aim:

Pregnancy in women with epilepsy (WWE) who are on anti-epileptic drugs (AEDs) has two- to three-fold increased risk of fetal malformations. AEDs are mostly metabolized by Cyp2C9, Cyp2C19 and Cyp3A4 and transported by ABCB1. Patients on AED therapy can have folate deficiency. We hypothesize that the polymorphisms in ABCB1, Cyp2C9, Cyp2C19 and methylene tetrahydrofolate reductase (MTHFR) might result in differential expression resulting in differential drug transport, drug metabolism and folate metabolism, which in turn may contribute to the teratogenic impact of AEDs.

Materials and Methods:

The ABCB1, Cyp2C9, Cyp2C19 and MTHFR polymorphisms were genotyped for their role in teratogenic potential and the nature of teratogenecity in response to AED treatment in WWE. The allelic, genotypic associations were tested in 266 WWE comprising of 143 WWE who had given birth to babies with WWE-malformation (WWE-M) and 123 WWE who had normal offsprings (WWE-N).

Results:

In WWE-M, CC genotype of Ex07 + 139C/T was overrepresented (P = 0.0032) whereas the poor metabolizer allele *2 and *2 *2 genotype of CYP2C219 was significantly higher in comparison to WWE-N group (P = 0.007 and P = 0.005, respectively). All these observations were independent of the nature of malformation (cardiac vs. non cardiac malformations).

Conclusion:

Our study indicates the possibility that ABCB1 and Cyp2C19 may play a pivotal role in the AED induced teratogenesis, which is independent of nature of malformation. This is one of the first reports indicating the pharmacogenetic role of Cyp2C19 and ABCB1 in teratogenesis of AED in pregnant WWE.

Pharmacotherapy of focal epilepsy

INTRODUCTION

Epilepsy is the most common neurological condition worldwide with significant psychosocial and physical morbidity. Its management requires expertise and good pharmacological knowledge of the available options.

AREAS COVERED

This review covers the management of focal epilepsy addressing the common questions arising through the patients' journey, including timing of starting initial treatment, monotherapy options, add-on treatment for refractory cases and withdrawal of medication during remission.

EXPERT OPINION

Initiating anti-epileptic drug (AED) treatment requires assessment of patient preferences and of evidence of benefit and harm. Evidence of benefit will come primarily from randomised controlled trials, although in epilepsy, most trials are undertaken to inform regulatory decision and have important limitations for informing clinical decisions. Evidence about harm may come not only from randomised trials but also from other sources. Most patients will start treatment following a second focal seizure. Carbamazepine and lamotrigine are good initial monotherapy options. Newer AEDs have proof of efficacy as monotherapy but evidence is insufficient to recommend them as first-line treatments. For refractory cases, there are an increasing number of AEDs available, but evidence of efficacy is primarily from placebo-controlled trials, and there is no robust evidence to inform a choice among treatments.

Gender issues in antiepileptic drug treatment

The purpose of this review is to discuss gender-related aspects in the, pharmacokinetics, effects, selection and use of antiepileptic drugs (AED). In general, there are few known gender related differences in pharmacokinetics or efficacy of AEDs. Conversely, gender has a significant influence on the susceptibility to certain adverse effects, not the least those involving alterations in sex hormone metabolism. Particularly relevant are the teratogenic effects of AEDs, with important differences among AEDs in their potential to cause adverse effects on the fetus when used during pregnancy. Pregnancy can also markedly affect the pharmacokinetics of several AEDs, and dose adjustments are often needed during pregnancy to maintain seizure control. Some treatments that are used only by women, such as contraceptive steroids and hormone replacement therapy, can also interact with AEDs to an extent that may affect the utilization of both the AEDs and the other drug.

[Treatment of manic phases of bipolar disorder: critical synthesis of international guidelines]

INTRODUCTION

Bipolar disorder (BD) is the seventh leading cause of disability per year of life among all diseases in the population aged 15 to 44. It is a group of heterogeneous diseases, with frequent comorbid psychiatric or somatic disorders, variable treatment response and frequent residual symptoms between episodes. The major impairment associated with this disorder is related to the high relapse and recurrence rates, the functional impact of comorbidities and cognitive impairment between episodes. The prognosis of the disease relies on the efficacy of relapse and recurrence prevention interventions. Given the heterogeneity of the disorder, relapse and recurrence prevention needs to develop a personalized care plan from the start of the acute phase. In such a complex situation, guideline-driven algorithms of decision are known to improve overall care of patients with bipolar disorder, compared to standard treatment decisions. Although guidelines do not account for all the situations encountered with patients, this systematic approach contributes to the development of personalized medicine.

METHODS

We present a critical review of recent international recommendations for the management of manic phases. We summarize treatment options that reach consensus (monotherapy and combination therapy) and comment on options that differ across guidelines.

RESULTS

The synthesis of recent international guidelines shows a consensus for the initial treatment for manic phases. For acute and long-term management, the anti-manic drugs proposed are traditional mood stabilizers (lithium or valproate) and atypical antipsychotics (APA - olanzapine, risperidone, aripiprazole and quetiapine). All guidelines indicate stopping antidepressant drugs during manic phases. International guidelines also present with some differences. First, as monotherapy is often non sufficient in clinical practice, combination therapy with a traditional mood stabilizer and an APA are disputed either in first line treatment for severe cases or in second line. Second, mixed episodes treatment is not consensual either and some guidelines propose in first line valproate, carbamazepine and some APA, and advice not to use lithium. On the other hand, some guidelines do not propose specific treatment for mixed episodes and group them with manic episodes management. Duration of treatment is unclear.

CONCLUSION

Guidelines utilization has shown that the systemic use by clinicians of decision algorithms in comparison to "treatment as usual" modality improves the overall care of patients with BD. Future data from cohorts of patients seem necessary to complement the existing data from clinical trials. These cohort studies will help to take into account the different individual profiles of BD and thus may help to propose a more personalized medicine.

Concomitant therapy in people with epilepsy: potential drug-drug interactions and patient awareness

People with epilepsy (PWE) may use prescription and over-the-counter (OTC) drugs for the treatment of concomitant diseases. Combinations of these drugs, as well as dietary supplements, with antiepileptic drugs (AEDs) may lead to reduced control of seizures and of coexisting medical conditions and increased risk of adverse drug reactions (ADRs). The aims of this study were to obtain comprehensive lists of medications, dietary supplements, botanicals, and specific food components used by adult PWE and to evaluate the potential for interactions involving AEDs and patients' awareness of such potential interactions. We conducted a prospective, questionnaire-based study of PWE attending the Hadassah-Hebrew University Epilepsy Clinic over a period of 7months. The questionnaire interview included the listing of medications, medicinal herbs, dietary supplements, and specific food components consumed and the knowledge of potential drug-drug interactions (DDIs), and it was conducted by a pharmacist. Drug-drug interactions were analyzed via the Micromedex online database. Out of 179 patients who attended the clinic over the study period, we interviewed 73 PWE, of which 71 were included in our final analysis. The mean number of AEDs consumed per subject was 1.7 (SD: 0.8, range: 1-4). Forty (56%) subjects were also treated with other prescription and/or OTC medications, and thirty-four (48%) took dietary supplements. Drug families most prone to DDIs involving AEDs included antipsychotic agents, selective serotonin reuptake inhibitors, and statins. Two-thirds of study participants (67%) knew that DDIs may lead to ADRs, but only half (56%) were aware of the potential for reduced seizure control. Only 44% always reported treatment with AEDs to medical professionals. This study provides for the first time a comprehensive picture of prescription and OTC drugs and food supplements used by PWE. Despite a considerable potential for DDIs involving AEDs, patient awareness is limited, highlighting the importance of patient and caregiver education.

Fetal growth restriction and birth defects with newer and older antiepileptic drugs during pregnancy

The primary aim of this study was to assess the risks of fetal growth restriction and birth defects in children exposed prenatally to newer and older antiepileptic drugs, using an unselected epilepsy cohort. Deliveries recorded in the compulsory Medical Birth Registry of Norway 1999-2011 formed the study population. All 2,600 children exposed to antiepileptic drugs during pregnancy were compared to all 771,412 unexposed children born to women without epilepsy. Children of untreated mothers with epilepsy served as an internal control group. The main outcomes were small for gestational age birth weight and head circumference, and major congenital malformations. Children exposed to antiepileptic drugs had a moderate risk of growth restriction. Infants exposed to topiramate had a considerable risk of microcephaly (11.4 vs. 2.4 %; OR 4.8; CI 2.5-9.3) and small for gestational age birth weight (24.4 vs. 8.9 %; OR 3.1; 95 % CI 1.9-5.3). Carbamazepine, lamotrigine, levetiracetam, oxcarbazepine, gabapentin, and pregabalin had low malformation rates, whereas topiramate tended to have an elevated malformation rate. Valproate monotherapy was associated with a significant risk of birth defects (6.3 vs. 2.9 %; OR 2.5; CI 1.6-3.8), and specifically with septal heart defects and hypospadias. For mothers using valproate, the presence of major birth defect in one child was associated with a markedly increased risk for the siblings (42.9 vs. 6.7 %; OR 10.4; CI 2.3-46.7). Children of untreated mothers with epilepsy had malformation risk similar to the reference group. In conclusion, topiramate was associated with a substantial risk of fetal growth restriction, and possibly an increased malformation rate. Other newer-generation antiepileptic drugs had a low malformation rate. Valproate monotherapy had a significant malformation risk, especially in repeated pregnancies.

MODEL-BASED LAMOTRIGINE CLEARANCE CHANGES DURING PREGNANCY: CLINICAL IMPLICATION

Objective

The objective of the study was to characterize changes in the oral clearance (CL/F) of lamotrigine (LTG) over the course of pregnancy and the postpartum period through a model-based approach incorporating clinical characteristics that may influence CL/F, in support of developing clinical management guidelines.

Methods

Women receiving LTG therapy who were pregnant or planning pregnancy were enrolled. Maternal blood samples were collected at each visit. A pharmacokinetic analysis was performed using a population-based, nonlinear, mixed-effects model.

Results

A total of 600 LTG concentrations from 60 women (64 pregnancies) were included. The baseline LTG CL/F was 2.16 L/h with a between-subject variability of 40.6%. The influence of pregnancy on CL/F was described by gestational week. Two subpopulations of women emerged based on the rate of increase in LTG CL/F during pregnancy. The gestational age-associated increase in CL/F displayed a 10-fold higher rate in 77% of the women (0.118 L/h per week) compared to 23% (0.0115 L/h per week). The between-subject variability in these slopes was 43.0%. The increased CL/F at delivery declined to baseline values with a half-life of 0.55 weeks.

Interpretation

The majority of women had a substantial increase in CL/F from 2.16 to 6.88 L/h by the end of pregnancy, whereas 23% of women had a minimal increase. An increase in CL/F may correspond to decreases in LTG blood concentrations necessitating the need for more frequent dosage adjustments and closer monitoring in some pregnant women with epilepsy. Postpartum doses should be tapered to preconception dose ranges within 3 weeks of delivery.

Prenatal exposure to antiepileptic drugs and dental agenesis

OBJECTIVE

The aim of the study was to investigate the association between prenatal exposure to AEDs and the risk of dental agenesis and to differentiate between the possible effects of the different drugs used.

METHODS

Data on 214 exposed and 255 unexposed children, aged 12-18 years, were extracted from the Prescription Database of the Central Denmark Region and North Denmark Region and the Danish Medical Birth Registry. The children's dental charts were examined for the presence of dental agenesis.

RESULTS

Overall, children exposed to AED in utero had an increased risk of developing dental agenesis, but as a group, the difference was not significant (OR = 1.7; [95% CI: 0.8-3.6]). The risk of developing dental agenesis was three-fold increased (OR = 3.1; [95% CI: 1.3-7.4]) in children exposed to valproate in mono- or in poly-therapy with other AEDs than carbamazepine or oxcarbazepine. The risk was further increased (OR = 11.2; [95% CI: 2.4-51.9]) in children exposed to valproate and carbamazepine or oxcarbazepine in combination.

CONCLUSIONS

The present study shows that dental agenesis is a potential congenital abnormality that is related to prenatal exposure to valproate, and dental agenesis may be considered a sensitive marker for the teratogenicity of valproate.

Use of Psychotropic Medication during Pregnancy and the Postpartum Period

Women with active psychiatric disorders who become pregnant face treatment dilemmas. Although results from studies are inconsistent, small but significant, risks on birth outcomes occur with exposure to untreated disorders, as well as to psychotropic medications. Prenatal antidepressant medication exposure may increase the risk for spontaneous miscarriage, preterm birth, cardiac malformations, persistent pulmonary hypertension of the newborn and postnatal adaptation syndrome. The use of valproate is contraindicated during pregnancy due to teratogenicity and neurocognitive delay and deficits. This review of selected studies will highlight some of the current issues with the use of psychotropic medications during pregnancy and the postpartum period.

Practitioner review: schizophrenia spectrum disorders and the at-risk mental state for psychosis in children and adolescents--evidence-based management approaches

BACKGROUND

Schizophrenia spectrum disorders are severe mental illnesses which often result in significant distress and disability. Attempts have been made to prospectively identify and treat young people viewed as at high risk of impending nonaffective psychosis. Once a schizophrenia spectrum disorder has developed, prompt identification and management is required.

METHODS

This article reviews the literature relating to the assessment and management of 'at-risk mental states' (ARMS) and the treatment of schizophrenia spectrum disorders in children and adolescents. A systematic search of the literature was undertaken using EMBASE, MEDLINE, PsycINFO databases for the period January 1970-December 2012.

RESULTS

Evidence suggests that young people fulfilling the ARMS criteria are at high risk of adverse mental health outcomes but that the majority do not develop nonaffective psychosis over the medium term. Although clinical trial findings have been inconsistent, psychosocial approaches, such as cognitive behaviour therapy, may reduce the risk of transition to psychosis and improve some symptoms, at least over the short term. The effectiveness of psychotropic medication for the ARMS is uncertain although there is accumulating evidence for potential adverse effects of antipsychotic medication, even at low dose, in this population. For the schizophrenias, clinical trial findings suggest that, as in adults, antipsychotics should be selected on the basis of side-effect profile although clozapine may be helpful in treatment refractory illness. There are almost no studies of psychosocial treatments for schizophrenia in young people under 18, and some caution must be exercised when extrapolating the findings of adult studies to younger individuals.

CONCLUSIONS

A stepped care approach to the ARMS in young people represents a plausible potential management approach for those at high risk of serious mental health problems. However, predictive models currently lack precision and should focus on accurately identifying those at high risk for a variety of poor outcomes who may benefit most from intervention. There is also an urgent need for age-specific research in the area of psychosocial treatments for children and adolescents with schizophrenia.

Associations between particular types of fetal malformation and antiepileptic drug exposure in utero

OBJECTIVE

To study associations between patterns of fetal malformation and individual antiepileptic drugs taken during pregnancy.

METHODS

Multiple variable logistic regression and other statistical analyses of data relating to 1733 fetuses from 1703 pregnancies (147 of which were not exposed to antiepileptic drugs during pregnancy).

RESULTS

There were statistically significant (P < 0.05) associations between (i) valproate exposure and spina bifida, malformations of the heart and great vessels, digits, skull bones, and brain, but not hypospadias, cleft palate/lip and mouth abnormalities, (ii) topiramate exposure and hypospadias and brain maldevelopments, and (iii) carbamazepine (CBZ) exposure and renal tract abnormalities.

CONCLUSIONS

The valproate findings are mostly in keeping with the published literature, but the topiramate finding regarding hypospadias and the association between CBZ exposure and various renal tract abnormalities raise questions of organ specific teratogenesis. More extensive data are desirable, particularly in relation to topiramate, which is being used increasingly as a migraine prophylactic in women of childbearing potential.

Preventive pharmacologic treatments for episodic migraine in adults

OBJECTIVES

Systematic review of preventive pharmacologic treatments for community-dwelling adults with episodic migraine.

DATA SOURCES

Electronic databases through May 20, 2012.

ELIGIBILITY CRITERIA

English-language randomized controlled trials (RCTs) of preventive drugs compared to placebo or active treatments examining rates of ≥50 % reduction in monthly migraine frequency or improvement in quality of life.

STUDY APPRAISAL AND SYNTHESIS METHODS

We assessed risk of bias and strength of evidence and conducted random effects meta-analyses of absolute risk differences and Bayesian network meta-analysis.

RESULTS

Of 5,244 retrieved references, 215 publications of RCTs provided mostly low-strength evidence because of the risk of bias and imprecision. RCTs examined 59 drugs from 14 drug classes. All approved drugs, including topiramate (9 RCTs), divalproex (3 RCTs), timolol (3 RCTs), and propranolol (4 RCTs); off-label beta blockers metoprolol (4 RCTs), atenolol (1 RCT), nadolol (1 RCT), and acebutolol (1 RCT); angiotensin-converting enzyme inhibitors captopril (1 RCT) and lisinopril (1 RCT); and angiotensin II receptor blocker candesartan (1 RCT), outperformed placebo in reducing monthly migraine frequency by ≥50 % in 200-400 patients per 1,000 treated. Adverse effects leading to treatment discontinuation (68 RCTs) were greater with topiramate, off-label antiepileptics, and antidepressants than with placebo. Limited direct evidence as well as frequentist and exploratory network Bayesian meta-analysis showed no statistically significant differences in benefits between approved drugs. Off-label angiotensin-inhibiting drugs and beta-blockers were most effective and tolerable for episodic migraine prevention.

LIMITATIONS

We did not quantify reporting bias or contact principal investigators regarding unpublished trials.

CONCLUSIONS

Approved drugs prevented episodic migraine frequency by ≥50 % with no statistically significant difference between them. Exploratory network meta-analysis suggested that off-label angiotensin-inhibiting drugs and beta-blockers had favorable benefit-to-harm ratios. Evidence is lacking for long-term effects of drug treatments (i.e., trials of more than 3 months duration), especially for quality of life.

Seizures in pregnancy: epilepsy, eclampsia, and stroke

Seizures during pregnancy complicate <1% of all gestations; however, they are associated with increased adverse maternal and perinatal outcomes (acute and long term). The differential diagnosis of seizures in pregnancy is extensive. Determining the underlying etiology is crucial in the management of these patients. Medical providers caring for pregnant women should be educated about possible etiologies of seizures during pregnancy and the importance of prompt management of these women in a timely fashion. Evaluation and management should be performed in a stepwise fashion and may require a multidisciplinary approach with other specialties such as neurology. The objective of this review is to increase awareness and to provide a stepwise approach toward the diagnosis and management of pregnancies complicated by seizures.

Exposure to antiepileptic drugs in utero and child development: a prospective population-based study

PURPOSE

Antiepileptic drugs may cause congenital malformations. Less is known about the effect on development in infancy and childhood. The aim of this study was to examine whether exposure to antiepileptic drugs during pregnancy has an effect on early child development.

METHODS

From mid-1999 through December 2008, children of mothers recruited at 13-17 weeks of pregnancy were studied in the ongoing prospective Norwegian Mother and Child Cohort Study. Information on birth outcomes were obtained from the Medical Birth Registry (108,264 children), and mothers reported on their child's motor development, language, social skills, and autistic traits using items from standardized screening tools at 18 months (61,351 children) and 36 months (44,147 children) of age. The relative risk of adverse outcomes in children according to maternal or paternal epilepsy with and without prenatal exposure to antiepileptic drugs was estimated as odds ratios (ORs), using logistic regression with adjustment for maternal age, parity, education, smoking, depression/anxiety, folate supplementation, and child congenital malformation or low birth weight.

KEY FINDINGS

A total of 333 children were exposed to antiepileptic drugs in utero. At 18 months, the exposed children had increased risk of abnormal scores for gross motor skills (7.1% vs. 2.9%; OR 2.0, 95% confidence interval [CI] 1.1-3.7) and autistic traits (3.5% vs. 0.9%; OR 2.7, CI 1.1-6.7) compared to children of parents without epilepsy. At 36 months, the exposed children had increased risk of abnormal score for gross motor skills (7.5% vs. 3.3%; OR 2.2, CI 1.1-4.2), sentence skills (11.2% vs. 4.8%; OR 2.1, CI 1.2-3.6), and autistic traits (6.0% vs. 1.5%; OR 3.4, CI 1.6-7.0). The drug-exposed children also had increased risk of congenital malformations (6.1% vs. 2.9%; OR 2.1, CI 1.4-3.4), but exclusion of congenital malformations did not affect the risk of adverse development. Children born to women with epilepsy who did not use antiepileptic drugs had no increased risks. Children of fathers with epilepsy generally scored within the normal range.

SIGNIFICANCE

Exposure to antiepileptic drugs during pregnancy is associated with adverse development at 18 and 36 months of age, measured as low scores within key developmental domains rated by mothers. Exposures to valproate, lamotrigine, carbamazepine, or multiple antiepileptic drugs were associated with adverse outcome within different developmental domains.

Seizure control and treatment changes in pregnancy: observations from the EURAP epilepsy pregnancy registry

PURPOSE

To analyze seizure control, dose adjustments, and other changes of antiepileptic drug (AED) treatment during pregnancy in a large cohort of women with epilepsy entering pregnancy on monotherapy with carbamazepine, lamotrigine, phenobarbital, or valproate.

METHODS

Seizure control and AED treatment were recorded prospectively in 3,806 pregnancies of 3,451 women with epilepsy taking part in European and International Registry of Antiepileptic Drugs and Pregnancy (EURAP), an international AED and pregnancy registry.

KEY FINDINGS

Of all cases, 66.6% remained seizure-free throughout pregnancy. Generalized tonic-clonic seizures (GTCS) occurred in 15.2% of the pregnancies. Women with idiopathic generalized epilepsies were more likely to remain seizure-free (73.6%) than women with localization-related epilepsy (59.5%; p < 0.0001). Worsening in seizure control from the first to second or third trimesters occurred in 15.8% of pregnancies. The AED dose was increased during pregnancy in 26.0% and a second AED added to the initial monotherapy in 2.6% of all pregnancies. Seizures were more likely to occur in the first trimester in pregnancies with an increased drug load (35%; increased dose and/or addition of another AED) than in pregnancies without an increased drug load (15.3%) (p < 0.0001). Compared with other monotherapies, pregnancies exposed to lamotrigine were less likely to be seizure-free, 58.2% (p < 0.0001); had more GTCS, 21.1% (p < 0.0001); had a greater likelihood of deterioration in seizure control from first to second or third trimesters, 19.9% (p < 0.01), and were more likely to require an increase in drug load, 47.7% (p < 0.0001). The mean dose increases from the first to third trimesters were 26% for lamotrigine, 5% for carbamazepine, 11% for phenobarbital, and 6% for valproate. There were 21 cases of status epilepticus (10 convulsive): none with maternal mortality and only one with a subsequent stillbirth.

SIGNIFICANCE

Although the majority of women remain seizure-free throughout pregnancy, our data suggest that a more proactive approach to adjusting the dose of all AEDs in pregnancy should be considered, in particular for those pregnancies with seizures occurring in the first trimester and those exposed to lamotrigine, to reduce the risk of deterioration in seizure control.

Epilepsy in pregnancy: best evidence for care

Epilepsy is the most commonly encountered neurologic disorder during pregnancy. A majority of women with epilepsy continue antiepileptic drug regimens during pregnancy. To provide evidence-based care to women with epilepsy, it is critical that healthcare providers possess a basic knowledge of seizures, antiepileptic medications, and interventions specific to this patient population, as well as an understanding of the patient's basic needs and concerns. This article provides a discussion of seizure types, common antiepileptic medications, and provides evidence-based interventions related to the fetus and the mother during preconception, intrapartum, and postpartum periods.

Pregnancy, epilepsy, and women's issues

PURPOSE OF REVIEW

Optimal treatment of women with epilepsy includes consideration of the complex interactions of sex steroid hormones with epilepsy and antiepileptic drugs, and of the potential risks of any antiepileptic drug prescribed during a pregnancy.

RECENT FINDINGS

Clinical studies in women with epilepsy have provided a better foundation of knowledge about the complex relationships between cycling sex steroid hormones, seizure frequency, antiepileptic drugs, contraception, and neuroendocrine abnormalities. Pregnancy registries and observational studies have provided key data that allow for a better estimation of risks to the developing fetus.

SUMMARY

Understanding these key factors should enable informed treatment recommendations that can reduce adverse health effects in women with epilepsy and improve both seizure control and maternal and fetal outcomes.

The long-term safety of antiepileptic drugs

Antiepileptic drugs (AEDs) are used by millions of people worldwide for the treatment of epilepsy, as well as in many other neurological and psychiatric conditions. They are frequently associated with adverse effects (AEs), which have an impact on the tolerability and success of treatment. Half the people who develop intolerable AEs discontinue treatment early on after initiation, while the majority of people will continue to be exposed to their effects for long periods of time. The long-term safety of AEDs reflects their potential for chronic, cumulative dose effects; rare, but potentially serious late idiosyncratic effects; late, dose-related effects; and delayed, teratogenic or neurodevelopmental effects. These AEs can affect every body system and are usually insidious. With the exception of delayed effects, most other late or chronic AEs are reversible. To date, there is no clear evidence of a carcinogenic effect of AEDs in humans. While physicians are aware of the long-term AEs of old AEDs (the traditional liver enzyme-inducing AEDs and valproate), information about AEs of new AEDs (such as lamotrigine, levetiracetam, oxcarbazepine, topiramate or zonisamide), particularly of their teratogenic effects, has emerged over the years. Sporadic publications have raised issues about AEs of the newer AEDs eslicarbazepine, retigabine, rufinamide, lacosamide and perampanel but their long-term safety profiles may take years to be fully appreciated. Physicians should not only be aware of the late and chronic AEs of AEDs but should systematically enquire and screen for these according to the individual AED AE profile. Care should be taken for individuals with comorbid conditions that may render them more susceptible to specific AEs. Prevention and appropriate management of long-term AED AEs is expected to improve adherence to treatment, quality of life and control of epilepsy.