Endocrine effects of valproic acid therapy in girls with epilepsy: a prospective study

Thyroid functions as a parameter in monitoring of antiepileptic drugs

INTRODUCTION

Epilepsy is a chronic neurological disorder that is treated with multiple medications that can have significant side effects. This study investigated the potential effects of antiepileptic drugs on thyroid function.

METHODS

The participants in this study were epileptic adults who had been consistently monitored in follow-up care. The effects of antiepileptic drugs on the serum levels of the thyroid stimulating hormone (TSH), free T3 (fT3), and free T4 (fT4) of these patients were investigated retrospectively by comparing laboratory recordings in three defined periods: prior to antiepileptic drug treatment, between 6 months and 1 year of treatment (early stage), and after 1 year of treatment (late stage).

RESULTS

  A total of 300 epileptic patients (F/M: 175/125) were included in the study. Significant differences in TSH and fT4 serum levels in the late stage compared to the pre-treatment stage (p = 0.006 and p = 0.0005, respectively) were found. TSH values in the late stage of treatment were abnormally high in one case and low in five cases; all six of these cases had normal pre-treatment and early-stage TSH values. Patients who received monotherapy with valproic acid, levetiracetam or carbamazepine were evaluated separately and there was no statistically significant difference in TSH and fT3 levels, while fT4 levels were significantly increased during treatment in each treatment group.

CONCLUSIONS

A significant increase in TSH levels was found in epileptic patients on polytherapy. Our results give us the opportunity to highlight the potential unique or cumulative effect of antiepileptic drugs on thyroid hormone levels.

Is the prevalence of thyroid disease higher in children receiving antiepileptic medication? A systematic review and meta-analysis

PURPOSE

Antiseizure medications (ASM) have long been examined for their potential to induce thyroid dysfunction. The aim of this systematic review and meta-analysis was to assess the prevalence of thyroid disease in children up to 16 years receiving monotherapy with valproate (VPA), carbamazepine (CBZ) and levetiracetam (LEV).

METHODS

PubMed/MEDLINE, Cochrane/CENTRAL databases and the gray literature were searched to identify observational studies providing the prevalence of thyroid dysfunction in the target population under VPA, CBZ, or LEV monotherapy schemes. The results were pooled using a random-effects model, and additional subgroup analyses were performed for the three ASM groups.

RESULTS

Fifteen and thirteen studies met inclusion criteria for the qualitative and the quantitative analysis, respectively, with a total of 945 pediatric patients with prevalence data. Only VPA and CBZ were associated with thyroid dysfunction. The overall prevalence of thyroid abnormality was higher in children receiving ASM [odds ratio (OR) 6.82, 95% confidence interval (CI) 3.96-11.75]. In the subgroup analysis, the prevalence of biochemical thyroid abnormality with increased TSH was higher in the VPA (OR 9.54, 95%CI 5.25-17.34) and the CBZ group (OR 4.08, 95%CI 1.84-9.04) compared with controls.

CONCLUSION

This study confirms the higher prevalence of biochemical thyroid abnormality in children under VPA and CBZ monotherapy, whereas no such evidence is present for LEV. In children with a predisposition for thyroid disease, LEV should be considered over VPA and CBZ, if appropriate for seizure type and epilepsy syndrome. More studies are needed to reach a consensus on monitoring and management of thyroid dysfunction in children receiving ASM therapy.

Research Progress on the Effect of Epilepsy and Antiseizure Medications on PCOS Through HPO Axis

Epilepsy is a common chronic neurological disease that manifests as recurrent seizures. The incidence and prevalence of epilepsy in women are slightly lower than those in men. Polycystic ovary syndrome (PCOS), a reproductive endocrine system disease, is a complication that women with epilepsy are susceptible to, and its total prevalence is 8%-13% in the female population and sometimes as high as 26% in female epilepsy patients. The rate of PCOS increased markedly in female patients who chose valproate (VPA), to 1.95 times higher than that of other drugs. In addition, patients receiving other anti-seizure medications (ASMs), such as lamotrigine (LTG), oxcarbazepine (OXC), and carbamazepine (CBZ), also have reproductive endocrine abnormalities. Some scholars believe that the increase in incidence is related not only to epilepsy itself but also to ASMs. Epileptiform discharges can affect the activity of the pulse generator and then interfere with the reproductive endocrine system by breaking the balance of the hypothalamic-pituitary-ovarian (HPO) axis. ASMs may also cause PCOS-like disorders of the reproductive endocrine system through the HPO axis. Moreover, other factors such as hormone metabolism and related signalling pathways also play a role in it.

Photosensitive Epilepsy and Polycystic Ovary Syndrome as Manifestations of MERRF

Objectives

Although endocrinologic involvement and epilepsy are frequent features of myoclonic epilepsy with ragged-red fibers (MERRF), polycystic ovary syndrome (PCOS) and photosensitive epilepsy have not been reported. Case Report. A 32-year-old female was diagnosed with MERRF at age 19 y upon presence of the four canonical features and the variant m.8344A > G in MT-TK (tRNA (Lys)) (blood heteroplasmy rate: 50%). She experienced recurrent photosensitive focal and generalised seizures since age 19 y, which could be triggered by flickering light or by looking at small stones, leaves, or dirty snow on the ground. Since the last 42 months, she was seizure-free upon levetiracetam (4000 mg/d), clonazepam (1.5 mg/d), and topiramate (25 mg/d). Additionally, she suffered from secondary amenorrhoea since adolescence. She was married between ages 19 y and 25 y but did not get pregnant. PCOS was diagnosed and treated with desogestrel plus estradiol. Nonetheless, the course was progressive, particularly with regard to ataxia, myocloni, and myopathy.

Conclusions

The phenotypic spectrum of MERRF is broader than anticipated and may additionally include PCOS and photosensitive epilepsy. PCOS in MERRF may respond to hormone substitution and photosensitive epilepsy to levetiracetam, clonazepam, and topiramate.

[Pharmacogenetic markers of metabolic disorders in the treatment with valproic acid]

The review includes studies on the association between the use of VA drugs and weight gain in patients with epilepsy as well as other valproate-induced adverse drug reactions, including insulin resistance. Understanding the mechanisms of significant weight gain of patients taking VA drugs will help personalize antiepileptic therapy and minimize the risk of valproate-induced obesity.

Use of valproate and carbamazepine in the therapy of epilepsy (guidelines for the practitioner)

The paper gives comparative data on the efficacy and tolerability of valproic acid (VA, valproate) and carbamazepine (CBZ) for different types of epilepsy and seizures in different age and clinical groups. The results of studies suggest that despite a more than 50-year history of their effective use, the extended-release formulations of VA and CBZ remain the drugs of first choice for many types of epilepsy.

CBZ is effective for focal epilepsy and isolated generalized tonic-clonic seizures. However, its use is substantially limited by properties, such as cytochrome P450 induction and autoinduction, high drug-drug interactions, the aggravation of absences, negative myoclonus, myoclonic and atonic seizures, an effect on the profile of steroid sex hormones, elevated concentrations of atherogenic lipids and cholesterol, myocardial conduction disorders, and hyponatremia.

Due to the multiple mechanism of action, VA is prescribed for almost all types of epilepsy and seizures in patients of different ages. VA should not be used (if the clinical situation allows) in women of childbearing age, in some infantile epileptic encephalopathy, inherited metabolic diseases, and chromosomal abnormalities. Effectiveness against different types of seizures and epilepsy, good tolerability, minimal aggravation risk, high retention rate of monotherapy, the presence of a variety of dosage forms, and favorable pharmacokinetic and pharmacodynamic profiles still make VA essential in many clinical situations.

Comorbidities of Rare Epilepsies: Results from the Rare Epilepsy Network

OBJECTIVE

To describe the prevalence and characteristics of comorbidities in persons with rare epilepsies.

STUDY DESIGN

Persons with rare epilepsies and caregivers of those affected were recruited through the Epilepsy Foundation and more than 30 rare epilepsy advocacy organizations affiliated with the Rare Epilepsy Network (REN). A web-based survey was conducted using a questionnaire consisting of core sections to collect data from affected persons on various aspects, including comorbidities. Comorbidity information was grouped into 15 classes, 12 of which had a stem question followed by detailed branch questions and 3 that were created from a combination of related questions.

RESULTS

Of 795 persons with more than 30 different rare epilepsy diagnosis groups, one-half had ≥5 comorbidity classes and 97% were classified as complex chronic disease (C-CD). The highest number of comorbidity classes reported per person were persons with Aicardi syndrome, Phelan-McDermid syndrome (median, 7.0; IQR, 5.0-9.0), and tuberous sclerosis complex (median, 6.0; IQR, 4.0-8.0). The most common comorbidity classes were learning/developmental disability (71%), mental health issues (71%), sleep disorders (60%), brain abnormalities (52%), oral issues (49%), bone-joint issues (42%), hyper/hypotonia (42%), and eye-vision disorders (38%). The prevalence of brain abnormalities, hyper/hypotonia, eye, and cardiac disorders was significantly higher in persons first diagnosed with epilepsy at a younger age (<9 months) than in those first diagnosed at an older age (P < .05 for trend).

CONCLUSIONS

Nearly all persons with rare epilepsies are medically complex, with a high prevalence of multiple comorbidities, especially those who were diagnosed with epilepsy in the first year of life. Comorbidities should be carefully considered in the diagnosis and management of persons with rare epilepsies.

The effects of valproate and topiramate use on serum insulin, leptin, neuropeptide Y and ghrelin levels in epileptic children

PURPOSE

Although some drugs used in the treatment of epilepsy are known to affect body weight, the hormonal factors responsible have not been sufficiently described. The purpose of this study was to compare insulin, leptin, neuropeptide Y and ghrelin levels in children with epilepsy receiving monotherapy with topiramate (TPM) and valproic acid (VPA), the drugs whose effects on body weight have been most discussed, with those of a control group.

METHOD

48 patients (25 VPA, 23 TPM) aged between 6 and 15.5 years, presenting to the Karadeniz Technical University Medical Faculty Pediatric Neurology Clinic, diagnosed with idiopathic epilepsy or location-related idiopathic epilepsy, and receiving VPA or TPM monotherapy for at least 6 months were included in the study. Twenty-five healthy subjects with similar demographic characteristics were enrolled as the control group. Blood samples were collected from the patient and control groups after fasting for at least 10-12 h and again 1 and 2 h postprandially. Body mass index (BMI) values were calculated for all cases. VPA levels, glucose, insulin, leptin, neuropeptide Y and ghrelin were investigated in all three separate blood samples.

RESULTS

Age, height, weight and BMI were similar between the patient and control groups. Significant weight gain was observed throughout treatment in the VPA group compared to the TPM group. High fasting and postprandial insulin levels were observed in the VPA group. VPA group leptin and neuropeptide Y (NPY) levels were also higher than in the TPM and control groups. No significant difference was determined in ghrelin levels in the patient groups compared to the controls.

CONCLUSION

Low blood sugar not being observed, even though insulin levels are high, after fasting and in the postprandial period in epileptic children receiving VPA is indicative of insulin resistance. The elevation in leptin and neuropeptide Y levels observed in the VPA group also suggest this.

Computational elucidation of the reaction mechanism for synthesis of pyrrolidinedione derivatives via Nef-type rearrangement – cyclization reaction

This paper reports a quantum chemical study of all stages of a one-pot synthesis of pyrrolidinedione derivatives from nitromethane and coumarin, which includes Michael addition, migration of an oxygen atom (Nef-type rearrangement), and cyclization to a pyrrolidine ring. The energy barrier of deprotonated nitromethane addition to coumarin is 21.7 kJ mol⁻¹, while the barrier of proton transfer from the methylene to the nitro group in the nitromethyl group is notably higher, 197.8 kJ mol⁻¹. The second stage of the reaction, migration of an oxygen atom within the nitromethyl group, occurs with lowest energy barrier, 142.4 kJ mol⁻¹, when it is assisted by an additional water molecule. The last stage – cyclization, passes with a very low energy barrier of 11.9 kJ mol⁻¹ but the tautomerization of the nitrosohydroxymethyl group to the hydroxy-N-hydroxyiminomethyl, necessary for the process, has an energy barrier of 178.4 kJ mol⁻¹. Analogous calculations for the same process with the ethyl ester of 3-coumarin-carboxylic acid as substrate show that the relative energies of the intermediates and transition states are by at most 10–16 kJ mol⁻¹ more stable than the corresponding structures with coumarin.

A quantum chemical study of all stages of pyrrolidinedione derivative synthesis from nitromethane and coumarin, which includes Michael addition, migration of an oxygen atom (Nef-type rearrangement), and cyclization to a pyrrolidine ring is reported.

Growth and endocrine function in children with Dravet syndrome

PURPOSE

Dravet syndrome is an intractable childhood epilepsy syndrome most often associated with an SCN1A mutation. In our clinical practice, several patients with Dravet syndrome were noted to have short stature and endocrine dysfunction. This has not been reported in the literature. Our study aim was to describe growth measurements and endocrine abnormalities in children with Dravet syndrome.

METHOD

A retrospective chart review was performed at a single institution. Eligibility criteria included clinical and genetic (SCN1A) diagnosis of Dravet syndrome. Records were reviewed for height and weight measurements and serologic evidence of endocrine abnormality, as well as patient demographics, anti-seizure medication, and family history. Age and gender specific trend of height and weight measurements, using z-scores, were compared to CDC growth curves (Centers for Disease Control and Prevention [1]).

RESULTS

Sixty-eight children were identified, 46% male, age 1-21 years, taking an average of 2.9 anti-seizure medications per patient. Mean growth parameter measurements were significant for decrease in height z-score of 0.10 (p=<0.001) and decrease in weight z-score of 0.09 (p=<0.01) for every year increase in age, such that with increasing age the cohort moved farther away from the mean. The average group height and weight z-score, at age 8, was -0.45 and -0.09, respectively. After adjusting for age, neither gender, family history, or anti-seizure medication was associated with height or weight z-score. Serologic endocrine results were available for 26 children (38%). This identified low insulin-like growth factor 1 (IGF-1) in 7/15 and low testosterone in 2/10. Two children received growth hormone supplementation. TSH testing was abnormal <10% of the time.

CONCLUSIONS

Comorbidities in children with Dravet syndrome may involve more systems than previously reported. We report a cohort of children with Dravet syndrome with reduced height and weight growth trend, as well as a subset with endocrine dysfunction evidenced by low IGF-1 and testosterone levels. Additional prospective research is needed to further define the significance of this relationship.

[Algorithms of using valproic acid drugs in women]

Characteristics of using valproic acid drugs in women, from puberty to menopause period, are reviewed. Based on initial treatment efficacy, type of epileptic seizures and a form of epilepsy, the author emphasizes the practical use of valproates during pregnancy in dependence on the situation. Several scenarios of pregnancy course and possible treatment tactics are presented.