2005 AES Annual Course: Evidence Used to Treat Women with Epilepsy

Effect of antiepileptic drugs on serum biochemical marker levels of first and second trimester screening tests

OBJECTIVES

Our aim in this study was to evaluate the effect of antiepileptic drugs on biochemical components of screening tests.

MATERIALS AND METHODS

This longitudinal case-control study was performed at Ankara City Hospital, Ankara, Turkey, from June 2020 to January 2021. The case group included epileptic singleton pregnant women which were using antiepileptic drugs, between 18 and 44 years of age. The control group included healthy pregnant women between 18 and 44 years old who did not use any drugs. Maternal medical, obstetric, and gynecological history were recorded. The antiepileptic agents that are used in our study were; lamotrigine, levetiracetam, carbamazepine, oxcarbazepine, valproic acid, and clonazepam. For the aneuploidy screening program conducted in our laboratory, the biochemical markers that are analyzed include; free b-hCG and PAPP-A in the first trimester, as well as AFP, HCG, and unconjugated estriol (uE3) in the second trimester. MoM values of these markers were compared between the case and control groups.

RESULTS

Fifty-three pregnant women with epilepsy using antiepileptic drugs were compared with 106 healthy pregnant women. The levels of serum-free b-hCG, and PAPP-A were similar between the case and control groups (p = 0.653, p = 0.351). For the second-trimester screening biochemical markers, the maternal serum uE3 and AFP levels expressed as MoM were significantly higher in the epileptic group than in the control patients (p = 0.015 and p = 0.001).

CONCLUSION

Serum marker levels of second-trimester screening tests may be affected by antiepileptic drugs, which may lead to misinterpretation of the risk level. Antiepileptic drug usage should be considered when evaluating screening test results.

Pharmacokinetic considerations for anti-epileptic drugs in children

INTRODUCTION

Epilepsy is a chronic and debilitating neurological disease, with a peak of incidence in the first years of life. Today, the vast armamentarium of antiepileptic drugs (AEDs) available make even more challenging to select the most appropriate AED and establish the most effective dosing regimen. In fact, AEDs pharmacokinetics is under the influence of important age-related factors which cannot be ignored. Areas covered: Physiological changes occurring during development age (different body composition, immature metabolic patterns, reduced renal activity) can significantly modify the pharmacokinetic profile of AEDs (adsorption, volume of distribution, half-life, clearance), leading to an altered treatment response. We reviewed the main pharmacokinetic characteristics of AEDs used in children, focusing on age-related factors which are of relevance when treating this patient population. Expert opinion: To deal with this pharmacokinetic variability, physicians have at their disposal two tools: 1) therapeutic drug concentration monitoring, which may help to set the optimal therapeutic regimen for each patient and to monitor eventual fluctuation, and 2) the use of extended-release drug formulations, when available. In the next future, the development of 'ad-hoc' electronic dashboard systems will represent relevant decision-support tools making the AED therapy even more individualized and precise, especially in children.

Levetiracetam use during pregnancy in women with epilepsy: Preliminary observations from a tertiary care center in Northern India

INTRODUCTION

Data on efficacy and safety of levetiracetam (LEV) during pregnancy is still limited. We analyzed efficacy and safety of LEV during pregnancy in North Indian women with epilepsy (WWE) which is being presented here.

PATIENTS AND METHODS

This retrospective study included 99 WWE (on treatment with a single antiepileptic drug [AED]) who were evaluated in medical-surgical disorder antenatal clinic of the department of obstetrics and gynecology at a tertiary care teaching hospital and referral center in North India. All the obstetric and fetal data as well as data pertaining to epilepsy were noted meticulously.

RESULTS

In this study (n = 99), 35 women received carbamazepine, 28 received LEV, 15 received valproate (VPA), 13 received phenytoin (PHT), three each received oxcarbazepine and lamotrigine, respectively, and two received clobazam. Although the use of VPA was associated with significantly better control of seizures compared to LEV, its use was associated with higher risk of major congenital malformations (13.3%). The incidence of gestational hypertension was lower while incidence of fetal distress was significantly higher in WWE receiving PHT during pregnancy. None of the child born to pregnant women receiving LEV had any congenital malformation.

CONCLUSION

LEV is a first-line AED during pregnancy. Future prospective studies using therapeutic drug monitoring during pregnancy may further help in establishing its role during pregnancy.

First and Second Trimester Biochemical Markers in Maternal Epilepsy: A Case-Control Study

BACKGROUND

Our aim is to investigate whether the maternal serum levels of first and second trimester serum analytes are altered in women with epilepsy in pregnancy.

METHODS

Maternal serum biochemical markers (estriol, alpha-fetoprotein [AFP], human chorionic gonadotrophin [hCG], free β hCG, pregnancy-associated plasma protein-A) were compared in a series of 122 pregnant women with epilepsy and in a cohort of 122 normal pregnant women. The serum samples were obtained between 11-13 6/7 weeks and 16-18 weeks gestation.

RESULTS

Second trimester serum estriol levels, expressed as multiples of the median (MoM), in the epileptic group (1.55 ± 0.77 MoM) were significantly higher than those in the control patients (1.13 ± 0.40 MoM) (p < 0.001). Of the women with epilepsy, 66.3% (n = 81) were exposed to antiepileptic drugs.

CONCLUSION

Our study revealed that otherwise uncomplicated pregnant epileptic women had higher second trimester (18-20 weeks of gestation) estriol levels compared to non-epileptic pregnant women.

Pregnancy outcomes among women with epilepsy: A retrospective cohort study

OBJECTIVE

The objective of this study was to compare adverse pregnancy outcomes between pregnancies that involve epilepsy and those that do not and are identified as normal for the purposes of this paper.

METHODS

A retrospective cohort study was carried out by accessing the maternal-fetal medicine (MFM) database to identify and review records of singleton pregnancies with epilepsy but with no other underlying disease (study group). A parallel group of low-risk pregnancies was randomly allocated as the control group. The adverse outcomes between the two groups were compared. The primary outcomes included rates of spontaneous abortion, small for gestational age (SGA), preterm birth (PTB), low birth weight (LBW), and preeclampsia.

RESULTS

From a total of 44,708 deliveries, 148 pregnancies involving mothers with epilepsy and a control group of 1480 normal pregnancies were compared. The rates of spontaneous abortion, PTB, LBW, and cesarean section were slightly but significantly higher in the study group with a relative risk of 6.6 (95% confidence interval (CI): 1.9-23.3), 1.6 (95% CI: 1.1-2.2), 1.6 (95% CI: 1.1-2.3), and 1.5 (95% CI: 1.1-2.1), respectively, whereas other adverse outcomes were comparable. In the subgroup analysis, adverse outcomes tended to be higher in women with active epilepsy. However, only the rates of SGA in the group in which the disorder is active and PTB in the presence of seizures within 6months of conception were significantly increased.

CONCLUSIONS

Pregnancies with epilepsy, even in cases with multidisciplinary care and no other risk factors, are still significantly associated with higher adverse outcomes.

Clinical pharmacokinetic interactions between antiepileptic drugs and hormonal contraceptives

Contraceptive management in women with epilepsy is critical owing to the potential maternal and fetal risks if contraception or seizure management fails. This article briefly describes the pharmacokinetic interactions between antiepileptic drugs (AEDs) and hormonal contraceptives and the rational strategies that may overcome these risks. Hormonal contraception, including the use of oral contraceptives (OCs), is widely used in many women with epilepsy - there is no strong evidence of seizures worsening with their use. AEDs are the mainstay for seizure control in women with epilepsy. However, there are many factors to consider in the choice of AED therapy and hormonal contraception, since some AEDs can reduce the efficacy of OCs owing to pharmacokinetic interactions. Estrogens and progestogens are metabolized by cytochrome P450 3A4. AEDs, such as phenytoin, phenobarbital, carbamazepine, felbamate, topiramate, oxcarbazepine and primidone, induce cytochrome P450 3A4, leading to enhanced metabolism of either or both the estrogenic and progestogenic component of OCs, thereby reducing their efficacy in preventing pregnancy. OCs can also decrease the concentrations of AEDs such as lamotrigine and, thereby, increase the risk of seizures. Increased awareness of AED interactions may help optimize seizure therapy in women with epilepsy.

Antiepileptic drug treatment: new drugs and new strategies

PURPOSE OF REVIEW

Selection of the ideal antiepileptic drug (AED) for an individual patient can be a daunting process. Choice of treatment should be based on several factors, including but not limited to epilepsy classification, AED mechanism of action, AED side-effect profile, and drug interactions. Special consideration must be given to populations such as women, older adults, patients with other medical comorbidities, and patients who are newly diagnosed.

RECENT FINDINGS

Head-to-head trials between AEDs in newly diagnosed patients rarely demonstrate that one AED is more or less effective. The second-generation drugs, lamotrigine, topiramate, oxcarbazepine, zonisamide, and levetiracetam, have undergone head-to-head trials confirming similar efficacy and equal or better tolerability than standard drugs in focal epilepsy.

SUMMARY

A thoughtful approach to the AED selection process must factor in data from clinical AED trials as well as a variety of patient characteristics and confounding factors. When neurologists apply an individualized approach to AED drug selection for their patients, they can find an effective and well-tolerated drug for most patients.

[Family planning in women with epilepsy]

Epilepsy is a common neurological condition with gender-related management implications. Epilepsy and antiepileptic drug treatment affect aspects of contraception, fertility and pregnancy which are discussed in the article.

Genetic basis of susceptibility to teratogen induced birth defects

Birth defects remain the leading cause of infant death in US. The field of teratology has been focused on the causes and underlying mechanisms of birth defects for decades, yet our understanding of these critical issues remain unacceptably vague. Conclusions from years of animal and human studies made it clear that the vast majority of birth defects have multifactorial origins, with contributions from environmental and genetic factors. The environment comprises not only of the physical, biological, and chemical external environment surrounding the pregnant woman, but it also includes the internal environment of the woman's body that interact with the developing embryo in a complex fashion. The importance of maternal and embryonic genetic factors consisting of countless genetic variants/mutations that exist within every individual contribute to birth defect susceptibility is only now being more fully appreciated. This great complexity of the genome and its diversity within individuals and populations seems to be the principal reason why the same teratogenic exposure can induce severe malformation in one embryo, while fail to do so to other exposed embryos. As the interaction between genetic and environmental factors has long been recognized as the first "Principle of Teratology" by Wilson and Warkany [1965. Teratology: Principles and techniques. Chicago: University of Chicago Press], it is only recently that the appropriate investigative tools have been developed with which to fully investigate this fundamental principle. The introduction of high throughput technologies like whole genome sequencing or genome-wide association studies are promising to deliver an enormous amount of new data that will shed light on the genomic factors that contribute susceptibility to environmental teratogens. In this review, we attempt to summarize the epidemiological and experimental literature concerning birth defects whose phenotypic expression can be clearly related to the interactions between several select environmental factors and those genetic pathways in which they are most likely to have significant modifying effects. © 2011 Wiley-Liss, Inc.

The EULEV cohort study: rates of and factors associated with continuation of levetiracetam after 1 year

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT

Levetiracetam has shown good safety/tolerability and efficacy in regulatory trials. This was confirmed in observational investigations performed soon after marketing by using continuation or retention rates as a composite measure. When an anti-epileptic drug first becomes available; however, there is evidence of channelling to more severe patients than thereafter.

WHAT THIS STUDY ADDS

This study was performed several years after marketing of levetiracetam and found high rates of continuation. It also further explores this measure by determining the continuation in the absence of initiation of additional anti-epileptic drugs.

AIMS

To investigate real-life effectiveness of levetiracetam in patients initiating treatment in a stable market situation.

METHODS

Epileptic adults who had initiated levetiracetam between 1 January and 31 August in 2005 or 2006 were included and followed for 1 year by hospital or nonhospital neurologists practising in France. One-year continuation rates were estimated using Kaplan-Meier analysis. Among those still treated at end of study, treatment goals were investigated. Factors associated with discontinuation were investigated using Cox proportional hazards regression.

RESULTS

A total of 794 subjects were included in the cohort, and 753 subjects were followed up and included in the analysis. Among these, mean (SD) age was 42.6 (±17.0) years, 51.1% were female, 76.6% had partial epilepsy, 93.5% had seizures in the 6 months preceding levetiracetam initiation and 82.9% had at least one concomitant anti-epileptic drug when starting levetiracetam. One-year levetiracetam continuation rate was 83.5% (95% confidence interval, 80.5-86.0%). Of the 579 patients still using levetiracetam at end of study, 46.8% were seizure free during the last 6 months, and 24% were on levetiracetam monotherapy. Reasons for discontinuation (n= 122) were adverse events (45%), lack of efficacy (38%) or both (9%). Levetiracetam discontinuation was most strongly associated with previous exposure to more than four anti-epileptic drugs, whereas continuation was most strongly associated with presence of seizure-related falls in the 6 months preceding levetiracetam initiation.

CONCLUSIONS

This population-based cohort study in a stable market situation found a high 1 year levetiracetam continuation rate compared with previous studies done sooner after market introduction.

The treatment of women with epilepsy

BACKGROUND

Women with epilepsy and their doctors are often unsure of the implications of the disease and the limitations it causes. There is a major need for counseling.

METHODS

Selective review of the literature as of November 2009.

RESULTS

Recommendations on pregnancy and childbearing for women with epilepsy can be found in the guidelines issued by the German Societies of Neurology and Epileptology and by the American Epilepsy Society. Only low-level evidence is available on other relevant questions, including contraception, the influence of hormones on epilepsy, and the influence of antiepileptic drugs on endocrine and bone metabolism, because of a lack of controlled studies. Polycystic ovarian syndrome is more commonly seen in women with epilepsy who take valproate. Antiepileptic drugs that induce CYP3a can diminish the efficacy of oral contraceptives; conversely, oral contraceptives can markedly lower the blood levels of antiepileptic drugs. According to the most recent studies, the risk of congenital malformations and spontaneous abortions is 1% to 2% in the normal population and 3% to 9% in the offspring of women with epilepsy who are taking antiepileptic drugs. Women with epilepsy who want to have children are currently advised to take folic acid prophylactically starting before conception and until the end of the first trimester. New mothers with epilepsy are advised to breastfeed their children.

CONCLUSION

Proper treatment and counseling of women with epilepsy, with due attention to aspects that are specific to women patients, can reduce the limitations to which they are subject in everyday life.

Drug Information Rounds Levetiracetam Use in Pregnancy

Objective:

To review data evaluating levetiracetam management of epilepsy during pregnancy.

Data Sources:

A literature search of PubMed (1966–June 2009) was performed using the terms pregnancy, epilepsy, levetiracetam, and anticonvulsants. Bibliographies of all articles retrieved were reviewed to identify additional relevant articles.

Study Selection and Data Extraction:

All studies including humans and published in English with data describing levetiracetam management during pregnancy were included.

Data Synthesis:

The pharmacokinetic studies included in this review demonstrate that the clearance of levetiracetam increases during pregnancy, particularly during the third trimester, which subsequently leads to decreased serum levetiracetam concentrations. The increase in clearance is most likely due to an increase in renal blood flow. The teratogenic studies included in this review included a total of 147 patients. Of these patients, 2% experienced a major congenital malformation (MCM) and 4.8% experienced a minor anomaly. All of the patients who had either an MCM or a minor anomaly were receiving antiepileptic drug (AED) polytherapy. It was unknown whether 10.9% of the 147 patients discussed were receiving levetiracetam monotherapy or AED polytherapy. None of the published literature assessed adherence to AED therapy. Folic acid supplementation was addressed in only one of the case series presented.

Conclusions:

If levetiracetam is used during pregnancy, women should receive adequate amounts of folic acid (0.4–5 mg/day) and serum concentrations of levetiracetam should be determined before conception if possible and during each trimester, especially during the middle of the third trimester, to assess therapeutic concentrations. The dose may need to be increased during the third trimester to provide concentrations consistent with those before conception. Patients should be informed that there appears to be a small chance of malformations with levetiracetam, but that the data are limited.

Gender-specific psychosocial impact of living with epilepsy

Although many psychosocial issues affect all people living with epilepsy, certain issues either are specific to one gender or have a different prevalence or significance between men and women with epilepsy. Most studies suggest that the incidence of epilepsy is slightly higher in males with epilepsy. Sexual dysfunction is common among men and women with epilepsy and has been related to epilepsy type and treatment. Women living with epilepsy are often prone to increased seizure frequency at certain phases of their menstrual cycles. Hormone replacement therapy in postmenopausal women may worsen seizures. Treatment during pregnancy is often a precarious balancing act between the teratogenic risks of AEDs and the maintenance of maternal seizure control. However, pregnancy registries and other prospective studies have given us invaluable information on how to optimize treatment regimens as well as information about safety of breastfeeding. These gender-specific factors should be a key consideration when counseling and treating patients with epilepsy.

Antiepileptic drug interactions

INTRODUCTION

Antiepileptics are drugs used in the long-term treatment of epilepsy and other conditions such as pain or psychiatric diseases. They are often administered as polytherapy or in combination with other treatments. It is therefore important to know their potential interactions (with each other and with other substances) in order to avoid altering their efficacy or potentiating their side effects.

OBJECTIVE

The purpose of this article is to review these aspects and stress the most important interactions in day-to-day clinical practice.

RESULTS

Older antiepileptic drugs (AEDs) such as phenytoin, carbamazepine, phenobarbital and valproic acid can significantly interfere not only with each other and other AEDs, but also with other treatments. Although newer AEDs have a more favourable pharmacokinetic profile, they are not entirely exempt from interactions and they are also commonly administered in combination with older AEDs. Another aspect that should be considered is the existence of any clinically important pharmacokinetic and pharmacodynamic interactions in patients requiring the continuous administration of other treatments.

CONCLUSION

We must be aware of the pharmacokinetic and pharmacodynamic interactions of AEDs. Because of a lack of significant interactions, drugs such as levetiracetam, gabapentin or pregabalin can be recommended in particular groups such as patients with cancer, transplants, anticoagulant treatments or HIV infection. In all cases, it is important to ensure AED efficacy and prevent serious complications.

Women with epilepsy: hormonal issues from menarche through menopause

Epilepsy is a multilayered disorder complicated by numerous comorbid conditions and hormonal changes. More than 1.5 million girls and women with epilepsy face side effects that are compounded at different ages by menstruation, fertility, pregnancy, fetal health, bone health, and other health issues. Changes in hormonal balance during maturation, from menarche through menopause, affect seizure thresholds and antiepileptic drugs, and vice versa. This overview provides physicians with a background on the multiple issues relevant to women of all ages in the reproductive years, including those planning to conceive and those who are pregnant, and beyond the childbearing years.