Prolactin in partial epilepsy: an indicator of limbic seizures

Sex Differences in the Epilepsies and Associated Comorbidities: Implications for Use and Development of Pharmacotherapies

The epilepsies are common neurologic disorders characterized by spontaneous recurrent seizures. Boys, girls, men, and women of all ages are affected by epilepsy and, in many cases, by associated comorbidities as well. The primary courses of treatment are pharmacological, dietary, and/or surgical, depending on several factors, including the areas of the brain affected and the severity of the epilepsy. There is a growing appreciation that sex differences in underlying brain function and in the neurobiology of epilepsy are important factors that should be accounted for in the design and development of new therapies. In this review, we discuss the current knowledge on sex differences in epilepsy and associated comorbidities, with emphasis on those aspects most informative for the development of new pharmacotherapies. Particular focus is placed on sex differences in the prevalence and presentation of various focal and generalized epilepsies; psychiatric, cognitive, and physiologic comorbidities; catamenial epilepsy in women; sex differences in brain development; the neural actions of sex and stress hormones and their metabolites; and cellular mechanisms, including brain-derived neurotrophic factor signaling and neuronal-glial interactions. Further attention placed on potential sex differences in epilepsies, comorbidities, and drug effects will enhance therapeutic options and efficacy for all patients with epilepsy. SIGNIFICANCE STATEMENT: Epilepsy is a common neurological disorder that often presents together with various comorbidities. The features of epilepsy and seizure activity as well as comorbid afflictions can vary between men and women. In this review, we discuss sex differences in types of epilepsies, associated comorbidities, pathophysiological mechanisms, and antiepileptic drug efficacy in both clinical patient populations and preclinical animal models.

Antiepileptic drugs, sex hormones, and PCOS

Reproductive endocrine dysfunction in women with epilepsy is an important issue, and in recent years there is growing evidence to support the effect on sex hormones of both epilepsy per se and various antiepileptic drugs (AEDs). Focal epileptic discharges from the temporal lobe may have a direct influence on the function of the hypothalamic-pituitary axis, thereby altering the release of sex steroid hormones. The role of laterality and severity of epilepsy is still conflicting. The use of the liver enzyme-inducing AEDs--such as phenobarbital, phenytoin, and carbamazepine--can increase serum sex hormone-binding globulin concentrations, leading to diminished bioactivity of testosterone (T) and estradiol. Valproic acid, an enzyme inhibitor, has been associated with the occurrence of reproductive endocrine disorders characterized by high serum T, free androgen index, androstenedione, dehydroepiandrosterone sulfate concentrations, and with polycystic changes in ovaries and menstrual disorders. A better understanding of the effects of AEDs on sex hormones is key to selecting the appropriate AEDs and is crucial for reproductive health in female patients.

Epilepsy, sex hormones and antiepileptic drugs in female patients

Women with epilepsy have a higher incidence of reproductive endocrine disorders than the general female population. These alterations include polycystic ovary syndrome, hyperandrogenemia, infertility, hypothalamic amenorrhea and hyperprolactinemia. Reproductive dysfunction is attributed both to epilepsy itself and to antiepileptic drugs (AEDs). Focal epileptic discharges from the temporal lobe may have a direct influence on the function of the hypothalamic-pituitary axis, thus altering the release of sex steroid hormones, including the production of luteinizing hormone, follicle-stimulating hormone, gonadotropin-releasing hormone and prolactin. AEDs may modulate hormone release from the hypothalamic-pituitary-gonadal axis and they may alter the metabolism of sex hormones and their binding proteins. Hepatic enzyme-inducing AEDs, such as carbamazepine and phenytoin, may be most clearly linked to altered metabolism of sex steroid hormones, but valproic acid, an enzyme inhibitor, has also been associated with a frequent occurrence of polycystic ovary syndrome and hyperandrogenism in women with epilepsy. Therefore, treatment of epilepsy and selection of AEDs are important for reproductive health in female patients. The aim of the present review is to critically evaluate the recently published data concerning the interactions between sex hormones, epilepsy and AEDs.

Disorders of reproduction in patients with epilepsy: primary neurological mechanisms

Reproductive disorders are unusually common among women and men with epilepsy. They are generally associated with and may be the consequence of reproductive endocrine disorders. Both epilepsy itself and antiepileptic drug use have been implicated in their pathophysiology. This review focuses on how temporolimbic dysfunction in epilepsy may disrupt normal neuroendocrine regulation and promote the development of reproductive endocrine disorders. The particular nature of the dysregulation may relate to the laterality and focality of the epilepsy and some hormonal changes may develop in close temporal relation to the occurrence of epileptiform discharges. In women, reproductive endocrine disorders include polycystic ovary syndrome, hypothalamic amenorrhea, functional hyperprolactinemia, and premature menopause. In men, hypogonadism may be hypogonadotropic, hypergonadotropic or related to hyperprolactinemia. The significance of these reproductive endocrine disorders is that they may contribute not only to sexual dysfunction and infertility but may also have an adverse impact on seizure control.

Reversible Effects of Antiepileptic Drugs on Reproductive Endocrine Function in Men and Women with Epilepsy?A Prospective Randomized Double-Blind Withdrawal Study

PURPOSE

Epilepsy, antiepileptic drugs (AEDs), and reproductive endocrine function have complex interactions. In this study, we wanted to investigate the effects of AEDs on reproductive endocrine function after withdrawal of AEDs and look for reversible endocrine effects.

METHODS

The study was prospective, randomized, and double-blinded. A total of 160 patients were included and randomized to withdrawal or not and 150 (80 females, 53%) patients went through the intervention and was included in the study for 12 months. Complete serum samples from before and 4 months after completed withdrawal/no withdrawal were obtained from 130 patients (63 females, 48%).

RESULTS

The main finding was that reversible endocrine changes in sex steroid hormone levels could be observed in both sexes after withdrawal of AEDs. For CBZ, which was the drug used by the majority of the patients, withdrawal led to significant increases in serum testosterone concentrations and free androgen index (FAI) in both men (n = 19) and women (n = 19). Mean differences in change in FAI between the withdrawal group and nonwithdrawal group were in men 17.49 (CI 10.16-24.81, p <or= 0.001), and in women 1.61 (CI 0.62-2.61, p <or= 0.001).

CONCLUSION

Our findings provide further evidence of the potentially negative effects of CBZ treatment on reproductive endocrine functions in men and women, but also show that some of these changes may be reversible, even after years on treatment.

Reproductive endocrine function in women with epilepsy: the role of epilepsy type and medication

The purpose of the analysis described here was to assess reproductive endocrine disorders in 148 women with epilepsy (WWE) by epilepsy type and antiepileptic drug use. Women with idiopathic generalized epilepsy had a higher prevalence of reproductive endocrine disorders than control subjects. In addition, hyperandrogenism, polycystic ovaries, and polycystic ovary syndrome were more prevalent in WWE on valproate than in WWE taking other drugs or control women. The use of VPA was a predictor of the development of polycystic ovaries and polycystic ovary syndrome, and the use of valproate and younger age predicted the development of hyperandrogenism. In conclusion, both idiopathic generalized epilepsy and valproate were associated with an increased risk of reproductive endocrine disorders in WWE in this post hoc reanalysis of data on a large number of WWE. This was especially evident if the epilepsy was active and required treatment early in life.

Sex, hormones and affective arousal circuitry dysfunction in schizophrenia

Women with schizophrenia express affective disturbances disproportionately more than men. Brain regions implicated in the affective arousal circuitry also regulate the hypothalamic-pituitary-adrenal and -gonadal systems, which are dysfunctional in schizophrenia. This review will argue that understanding the etiology of affective arousal deficits in schizophrenia is intimately connected with characterizing the role of neuroendocrine dysfunction and sex effects in schizophrenia. Further, the etiology of these neuroendocrine deficits begins during fetal development, during a period of time that coincides with the sexual differentiation of the brain and the vulnerability for schizophrenia. Studying the links between deficits in neuroendocrine systems and the affective arousal system in schizophrenia will provide clues to understanding the development of sex differences in schizophrenia and thereby its etiology.

Effect of lamotrigine on sexual function in patients with epilepsy

OBJECTIVE

To assess the course of sexual function in epilepsy patients treated with lamotrigine.

MATERIAL AND METHODS

This open study included 141 patients treated with lamotrigine for a period of 8 months: 79 patients initiated treatment with lamotrigine monotherapy, and 62 were switched to lamotrigine because of lack of efficacy or adverse events to a previous antiepileptic drug (AED). Patients were assessed at baseline and after 4 and 8 months of treatment. In the baseline and final visits the Changes in Sexual Functioning Questionnaire (CSFQ) was applied. Analysis was performed in an intent-to-treat population.

RESULTS

In women who started treatment with lamotrigine, a significant improvement was observed, both in total CSFQ score (increase of 5.39 +/- 6.95 points; p < 0.05), and in the five dimensions of the scale (desire/frequency, desire/interest, pleasure, arousal/excitement and orgasm). In men, a significant improvement was only observed in the pleasure dimension. In the group of patients in whom a previous AED was substituted by lamotrigine, significant improvement was recorded in the dimensions of pleasure and orgasm in men and desire/frequency in women, whilst in women the desire/interest dimension showed a decrease.

CONCLUSIONS

In this observational study, an improvement in sexual dysfunction was observed in association with lamotrigine. This could have been the result of improvement of the epilepsy, changes in quality of life, elimination of side effects from other AEDs, or a mood-stabilizing effect of lamotrigine.

Effect of antiepileptic drugs on reproductive endocrine function in individuals with epilepsy

It is well known that epilepsy, antiepileptic drugs (AEDs), and the reproductive system have complex interactions. Fertility is lower in both men and women with epilepsy than in the general population. Moreover, reproductive endocrine disorders are more common among patients with epilepsy than among the population in general. These disorders have been attributed both to epilepsy itself and to use of AEDs. The use of the liver enzyme-inducing AEDs phenobarbital, phenytoin and carbamazepine increases serum sex hormone-binding globulin (SHBG) concentrations in both men and women with epilepsy. Over time, the increase in serum SHBG levels leads to diminished bioactivity of testosterone and estradiol, which may result in diminished potency in men and menstrual disorders in some women, and thus to reduced fertility. Liver enzyme-inducing AEDs also reduce the efficacy of oral contraceptives. Valproic acid medication may have effects on serum androgen concentrations and it reduces serum follicle stimulating hormone levels in men with epilepsy. However, the clinical significance of valproic acid-related reproductive endocrine changes in men is unknown. On the other hand, in women, use of valproic acid appears to be associated with a frequent occurrence of reproductive endocrine disorders characterised by polycystic changes in the ovaries, high serum testosterone concentrations (hyperandrogenism) and menstrual disorders. These disorders are especially common among women who have gained weight during valproic acid treatment. There are some discrepancies regarding the reported occurrence of reproductive endocrine disorders in women taking valproic acid for epilepsy. However, most studies also including patients receiving valproic acid for other reasons than epilepsy, and studies in different non-epileptic animal models, have shown an association between valproic acid medication and hyperandrogenism and related reproductive endocrine disorders. From a practical point of view, the length of the menstrual cycles and bodyweight should be monitored in women with epilepsy after commencement of treatment with valproic acid. A serum testosterone assay is helpful in following the possible biochemical endocrine changes. Ultrasonography of the ovaries (preferably transvaginal) is indicated if clinical assessment and serum testosterone measurement imply that there is a clinically significant valproic acid-related reproductive endocrine problem. That would be the case if the menstrual cycles were irregular or prolonged (usually >35 days) and serum testosterone levels elevated, especially with associated weight gain. The endocrine effects of the new AEDs have not been widely studied. However, it seems they may offer an alternative if reproductive endocrine problems emerge during treatment with the older AEDs.

Epilepsy and erectile dysfunction: a review

The association between epilepsy and erectile dysfunction (ED) has often been described but not clearly defined. This is a review of the literature regarding the current theories on the causes of ED in epilepsy, as well as the evaluation and treatment options available.

Interictal EEG discharges, reproductive hormones, and menstrual disorders in epilepsy

We evaluated reproductive endocrine function in women with unilateral temporolimbic epilepsy and normal control subjects to assess the effects of epilepsy, epilepsy laterality, and antiepileptic drug use on the cerebral regulation of hormonal secretion. The findings indicate that reproductive endocrine function differs between women with epilepsy and normal control subjects. Significant differences exist at all levels of the reproductive neuroendocrine axis, that is, hypothalamus, pituitary, and peripheral gland. Differences show significant relationships to the epilepsy itself as well as to medication use. Reproductive neuroendocrine changes occur in a stochastic manner such that the laterality of unilateral temporolimbic discharges is associated with predictable directional changes in hormonal secretion at all levels of the reproductive neuroendocrine axis. These directional changes are consistent with the finding that different reproductive disorders may develop in relation to left- and right-sided temporolimbic epilepsy. Hormonal changes can show close temporal relationship to the occurrence of interictal epileptiform discharges and may vary in relation to the laterality of the discharges. Antiepileptic drugs differ in their effects on reproductive hormone levels. There are notable differences between enzyme-inducing and noninducing drugs. Menstrual disorders are more common among women with interictal discharges as well as women with abnormal hormonal findings.

ECT of major depressed patients in relation to biological and clinical variables: a brief overview

The knowledge that spontaneous or induced convulsions can improve mental disorders has been present for several centuries. electroconvulsive therapy (ECT) has undergone fundamental changes since its introduction, and in the last 15-20 years there has been a legitimate renewal of interest for this therapy. Today the indications for use of ECT seem well codified, and its technique and practices have evolved considerably. It is now firmly established as an important and effective method of treating certain severe forms of depression. However, still very little is known about the mechanism of ECT. In this paper, first, we will give a short overview as to how far we have got concerning ECT in relation to various clinical and biological variables. Second, we will describe ECT in relation to electroencephalographic (EEG) technique and clinical outcome as well as give some proposals as to how to go on with the data analysis of EEG. In conclusion, the superior effect of ECT compared to other antidepressives in severe depression may depend on neurochemical and neurobiological cascade effects initiated by repeated treatments. Above all, ECT offers a unique experimental opportunity to study how neuromodulation of the major transmitter systems may be involved in brain dynamics and alteration of connectivity.

Prolactin levels in cerebrospinal fluid of patients with infantile spasms

Infantile spasms are an age-related epileptic syndrome of infancy and are characterized by the combination of clusters of epileptic spasms and specific electroencephalographic findings. The etiology and the pathogenesis of the disease is still unclear. Prolactin has been thought to be specifically related to epileptic seizures. To investigate the possible mechanism of prolactin secretion in infantile spasms cerebrospinal fluid prolactin levels were examined. Fifteen patients with infantile spasms (10 females and five males), 3-16 months of age, were evaluated and compared with age- and sex-matched control subject. Cerebrospinal fluid samples for prolactin were obtained before and after treatment. The mean prolactin levels in the cerebrospinal fluid of the patients before therapy (3.25 +/- 1.48 ng/mL) was higher than the control group (2.38 +/- 0.89 ng/mL), and the difference between the two groups was statistically significant (P < 0.001). The mean prolactin level in the cerebrospinal fluid of the patients after therapy (4.69 +/- 1.47 ng/mL) was demonstrated to be higher than the mean prolactin level before therapy (3.25 +/- 1.48 ng/mL) and the difference between the two groups was statistically significant (P = 0.037). Elevation of cerebrospinal fluid prolactin levels before and after treatment in patients with infantile spasms provided evidence that the cerebrospinal fluid prolactin level is related with neuronal injury.

Interictal and postictal alterations of pulsatile secretions of luteinizing hormone in temporal lobe epilepsy in men

Mesial temporal lobe epilepsy has been associated with abnormalities of reproductive physiology, but the mechanisms of hormonal dysregulation are not clear. Chronic effects of the epileptic state and the acute impact of seizures could alter hypothalamic function, which is represented by the downstream pulsatile secretion of luteinizing hormone. This study evaluates the interictal and postictal secretion of luteinizing hormone in mesial temporal lobe epilepsy. We characterized luteinizing hormone secretion in patients with mesial temporal lobe epilepsy during two 24-hour epochs: an interictal baseline and a postictal interval initiated by an electrographically confirmed spontaneous seizure. Males, rather than females, were studied so that menstrual cycles could not account for differences between epochs. Blood luteinizing hormone and prolactin (as a positive control) were measured every 10 minutes. Deconvolution analysis defined luteinizing hormone secretion in terms of interpulse interval, amplitude, and mass. Approximate entropy quantitated relative degradation in the orderliness of serial luteinizing hormone release. Interictal baseline epochs were compared to those of healthy controls with unpaired Student's t tests and between interictal and postictal epochs within epileptic patients with paired t tests. Ten epileptic men completed both interictal and postictal epochs. Interictally, seizure patients had lower mean concentrations, slower pulse rates, and higher peak amplitudes than healthy male controls. Within epileptic patients, mean interpulse interval, pulse amplitude, and pulse mass were not affected by the occurrence of seizures, whereas the orderliness of pulse mass decreased postictally. Acute seizures induced timing irregularity in luteinizing hormone secretion, whereas chronic epilepsy was associated with changes in luteinizing hormone pulse frequency, amplitude, and mass. Altered timing and regularity of neuroendocrine pulse patterns may underlie other disorders of homeostasis in mesial temporal lobe epilepsy.

Seizures, hormones and sexuality

Sexual disorders (both hyposexuality and sexual dysfunction) are common in people with epilepsy, occurring in up to two-thirds of patients. However, characteristically, patients do not spontaneously report these problems. Nocturnal penile tumescence testing suggests that the erectile dysfunction has a neurophysiological component. The aetiology remains uncertain but is likely to be multifactorial, involving neurological, endocrine, iatrogenic, cognitive, psychiatric and psychosocial factors. Epilepsy-related factors include the age of onset/duration of epilepsy along with the seizure type and focus. In addition, seizure frequency might be relevant as successful epilepsy surgery can result in an improvement in sexual functioning despite remaining on anticonvulsant medication. Endocrine changes (raised sex hormone binding globulin and reduced free testosterone) have been reported in men with epilepsy, especially when treated with hepatic-enzyme inducing antiepileptic drugs. Studies have not been performed evaluating anticonvulsants that do not induce hepatic enzymes such as lamotrigine. The association between these endocrine changes and hyposexuality is not known. The relationship between seizures, hormones and anticonvulsant medication in women is explored, focusing on issues such as catamenial epilepsy, the menopause, hormone replacement therapy and the polycystic ovarian syndrome. Suggestions for future research and treatment issues are discussed.

Circadian rhythms: interactions with seizures and epilepsy

Circadian rhythms are endogenously-mediated 24 h cycles of behavioral or physiological activity. The interactions among the mammalian circadian clock, acute seizures, and chronic epilepsy are not well-characterized. Evidence suggests that seizures are susceptible to circadian modulation, and that this modulation varies with epilepsy syndrome and location of seizure foci. The circadian timing system and secondary circadian cycles of hormone secretion, sleep and wakefulness, and recurrent environmental factors are discussed as potential systems that effect spontaneous seizure recurrence. Experimental designs should take into account time-of-day effects on seizure threshold and occurrence. Further work is required to determine what mechanisms account for daily variation in seizure susceptibility.

Prolactin levels in sudden unexpected death in epilepsy

PURPOSE

To assess serum prolactin levels in sudden unexpected death in epilepsy (SUDEP) and control groups to test the hypothesis that if seizures occur routinely as a terminal event in SUDEP, then raised prolactin levels may be an indicator of terminal seizure.

METHODS

Blood was taken for measurement of prolactin levels from subjects with SUDEP and three control groups. The control groups were those with epilepsy dying from causes other than epilepsy (e.g., ischemic heart disease or injuries), physiologically stressed individuals without epilepsy (they were admitted to the hospital after an acute illness and died after several hours to 3 days), and nonepileptic rapid deaths (these people collapsed suddenly and died at the scene). In the SUDEP group, evidence for terminal seizure was considered to be at least one of the following: body found half on, half off the bed, or urinary incontinence at the scene, or bitten lips or tongue at autopsy.

RESULTS

There was evidence for terminal seizure at the scene or at autopsy in four of the 10 SUDEP cases. Serum prolactin levels were not significantly increased in the SUDEP group compared with the controls. None of the SUDEP subjects, including those with clinical evidence of a terminal seizure, had high prolactin levels characteristic of those observed after seizures in living subjects.

CONCLUSIONS

Prolactin levels are not raised in SUDEP, even if there is evidence of terminal seizure. As prolactin takes 15-20 min to peak after a seizure in life, there may be insufficient time for a prolactin increase to occur in SUDEP. Thus prolactin levels cannot be used to determine if a deceased individual with epilepsy had a seizure or to answer the broad question whether SUDEP is always associated with a terminal seizure.

Hypothalamic neuronal loss and altered circadian rhythm of temperature in a rat model of mesial temporal lobe epilepsy

PURPOSE

Numerous dysfunctions in endogenous hypothalamic function have been associated with mesial temporal lobe epilepsy (MTLE). One endogenous activity is the circadian rhythm of temperature (CRT). In this study we examined whether hypothalamically mediated function is altered in the electrically induced, self-sustained, limbic status epilepticus model of MTLE. We then wished to determine whether there was a structural basis for regulatory alterations.

METHODS

We measured CRT with peritoneal temperature telemetry obtained in light-entrained (LD) and in free-running, constant-dark (DD) conditions. CRT from epileptic and controls of normal animals and kindled animals were quantized by fast Fourier transform-nonlinear least squares analysis to determine rhythmic complexity.

RESULTS

The circadian component of CRT was preserved in all animals. In DD, CRTs of epileptic animals were more complex than those of normal animals. CRT of kindled animals showed no increased complexity after electrically induced seizures. Neuronal density was decreased in regions of the anterior and posterior hypothalamus but not in the suprachiasmatic nuclei from the epileptic rats.

CONCLUSIONS

Alterations in CRT due to the epileptic state were independent of isolated seizures. Altered circadian thermoregulation in epileptic rats corresponded to regional hypothalamic neuronal loss. Structural changes of the hypothalamus may explain alterations in endogenous rhythms in MTLE.

Prolactin response to electroconvulsive therapy: effects of electrode placement and stimulus dosage

BACKGROUND

It is unclear whether the serum prolactin (PRL) surge following electroconvulsive therapy (ECT) is a marker of optimal ECT administration. We investigated the relations among PRL surge, stimulus parameters, and outcome in major depressive disorder (MDD).

METHODS

Seventy-nine patients with MDD were randomized in a double-blind trial to right unilateral (RUL) or bilateral (BL), and to low-dose (just above seizure threshold) or high-dose (2.5 x threshold) ECT.

RESULTS

Change in PRL (delta PRL) varied among treatment groups, with significant effects of electrode placement (BL > RUL, p < .006), electrical dosage (high > low, p < .04), and gender (female > male, p < .005). There was no evidence that clinical improvement was associated with greater PRL surge.

CONCLUSIONS

Although delta PRL varied with parameters impacting on response rates, these data indicate the PRL surge cannot serve as a useful index of clinically effective treatment. This finding does not support the view that diencephalic seizure propagation is necessary for ECT to exert therapeutic effects.

Using age-appropriate prolactin levels to diagnose children with seizures in the emergency department

OBJECTIVE

To assess the utility of serum and cerebrospinal fluid (CSF) prolactin levels for identifying children who have experienced seizures.

METHODS

A prospective cohort study was performed in a pediatric ED at an urban children's hospital. A convenience sample of children underwent blood and CSF analyses in the ED over a 2-year period.

RESULTS

Thirty-five children (aged 3 months-15 years) with generalized tonic-clonic seizures and 48 ill control patients were studied. Both groups included febrile and afebrile patients. The patient characteristics in the seizure and control groups were similar with respect to age, fever, current medications, and blood, urine, and CSF cultures. When serum prolactin levels were assigned age-adjusted dichotomous values of "elevated" or "normal," the rates of elevation between the seizure and control patients were different (p < 0.001). The positive and negative predictive values of these age-adjusted levels were 68% (95% CI 47-85%) and 76% (95% CI 61-87%), respectively. The mean CSF prolactin levels of the seizure and control groups were not significantly different. In addition, there was no single threshold CSF prolactin level that could delineate seizure patients from control patients.

CONCLUSIONS

Age-adjusted serum prolactin levels are useful only as an adjunct in the prospective evaluation of the individual pediatric patient for epileptic seizure activity. CSF prolactin levels are not useful in the diagnosis of generalized seizures in children in the acute care setting.

Maximizing the health of women with epilepsy: science and ethics in new drug development

Issues of unique concern to women with epilepsy largely arise from gender-based physiological differences. Female sex steroid hormones may alter the expression of epilepsy and the efficacy of antiepileptic drugs (AEDs). Seizures and AEDs in turn affect the hypothalamic-pituitary axis and can adversely impact reproductive function and bone health. Maternal seizures and exposure to AEDs may compromise fetal development. At this time, women with epilepsy and their medical caretakers do not have access to all the information necessary to formulate a treatment plan that will have the least impact on reproductive and general health. In part, this is because reproductive aged women are excluded from the earliest phases of drug testing and pregnant and lactating women are excluded from all aspects of new drug development. Therefore, as new AEDs enter the marketplace, women with epilepsy must decide whether a new AED is appropriate for therapy based on very limited information. Postmarketing surveillance of gender-specific adverse effects, as with all adverse effects, depends on voluntary reporting. Only a small percentage of significant adverse events are believed to be captured by the present system. Consumers, ethicists, and some physician groups are now arguing that women should be included in all aspects of the development of drugs they will ultimately use-even pregnant and lactating women. Some of the issues of concern for women with epilepsy regarding epilepsy treatment, reproductive function and general health will be reviewed, followed by a discussion of the drug development process and how it does, and could better, address the concerns of women.

Serum prolactin in neonates with seizures

We studied serum prolactin (PRL) in 28 newborn infants with acute encephalopathy. Six patients had electrographically confirmed seizures. Twenty-two patients comprised the nonictal group. In the seizure group, PRL was determined at the first onset of the seizure (baseline) and at 15 and 30 min postictal. In the nonseizure group, PRL was determined at the end of the EEG and 15 min later. EEGs were visually analyzed for the presence of seizures and background abnormality (normal or mildly, moderately, or markedly abnormal). Etiologic diagnoses included congenital heart disease (12), hypoxic-ischemic encephalopathy (4), sepsis (4), respiratory distress syndrome (5) meconium aspiration (1), and metabolic disease (2). Serum PRL was significantly higher (p < 0.05) at baseline and 15 min postictally in the patients with seizures than in the nonictal group. However, PRL levels 15 and 30 min postictally were not statistically different from baseline values. Baseline PRL correlated significantly (p < 0.001) with EEG background abnormality in both groups; therefore, patients with the most abnormal EEG backgrounds had higher levels of PRL than those with a relatively normal EEG background. We conclude that newborns with EEG-confirmed seizures, particularly if seizures are not associated with clinical signs, have high baseline serum PRL levels that do not increase significantly in the immediate postictal period. Serum PRL levels correlate with the severity of the brain insult as evaluated by EEG background. Further studies are needed to enhance our understanding of the dynamics of PRL secretion in newborns with seizures and acute encephalopathy.

Fasting studies in cerebrospinal fluid and blood in children with epilepsy of unknown origin

Alterations in the cerebral energy supply are likely to cause cerebral function disturbances. Fasting is a suitable method for studying the energy metabolism. As the cerebrospinal fluid (CSF) compartment reflects the brain metabolism, data in CSF might give information about the metabolism of fuel substrates in brain. We compared the biochemical data on several fuel-related components in blood and CSF at the end of a 40-hours fast of epileptic children with unknown origin of epilepsy (aged 6-15 years) with the values of a reference group of children. In children with primary generalized epilepsy no abnormalities were found. In children with complex partial epilepsy many significant abnormalities were found, such as low blood lactate and alanine and low CSF ketones and CSF blood ratio for ketones. The possible significance of the observed abnormalities are discussed.

Serum prolactin levels and neonatal seizures

To assess the effects of neonatal seizures on the hypothalamus and to test clinical use of prolactin as a neonatal seizure marker, we studied postictal and recovery baseline serum prolactin levels in 19 neonates whose seizures were classified according to their clinical and EEG features. Postictal prolactin levels were obtained 30 min after the seizure, and recovery levels were ascertained 2-4 days later. The ratio of postictal prolactin level to recovery baseline level (prolactin ratio) was used as an indicator of postictal prolactin increase. The specificity and sensitivity of a prolactin ratio of > 2 was compared with the current standard of diagnosis (seizure discharges recorded by ictal EEG). Infants with electroclinical seizures had significantly higher prolactin ratios than control infants or infants with seizures without EEG correlation. Marked prolactin increases were noted only in infants with focal tonic seizures and temporal electrode involvement. A prolactin ratio of > 2 had a specificity of 100% and a sensitivity of 40%. We conclude that neonatal seizures have variable effects on the hypothalamus and that the low sensitivity and the need to await recovery levels limit the clinical value of prolactin ratio as a neonatal seizure marker.

Plasma concentrations of prolactin, noradrenaline, vasopressin and oxytocin during and after a prolonged epileptic seizure

The time course and extent of changes in plasma prolactin, noradrenaline, vasopressin and oxytocin levels is reported following serial observations of a prolonged epileptic seizure arising in the temporal lobe, recorded by video-EEG-telemetry, in which the epileptic activity evolved from a simple partial to complex partial to secondarily generalised attack. The prolactin levels were markedly elevated during the phase of the simple partial seizure, at a time when consciousness was preserved, when motor activity was minimal and when EEG activity was highly localised. The hormonal levels continued to rise during the subsequent seizure evolution, suggesting that the duration (or intensity) of the seizure is an important, perhaps the most important, factor determining the degree of prolactin release during limbic seizures. Indeed, the prolactin elevation in this case (26 times the baseline level) is higher than any previously recorded, reflecting the unusual duration and intensity of this seizure. We did not observe the phenomenon of "exhaustion" of prolactin release and levels peaked after 49 min, and were high for over 2 h after the onset of the seizure, and after the convulsion had ceased. The concentrations of vasopressin, oxytocin and noradrenaline remained low during the aura, but rapidly increased during the phase of generalisation. The oxytocin and noradrenaline levels peaked during the phase of generalised convulsion, but the vasopressin levels peaked well into the post ictal phase, and remained high for several hours.(ABSTRACT TRUNCATED AT 250 WORDS)

Serum prolactin and cortisol in children with some paroxysmal disorders

Postictal serum prolactin and cortisol levels were estimated in 73 children having either epilepsy, febrile seizures, breath-holding spells, or fever without other manifestation and in 20 normal controls. Mean serum prolactin levels (28.6 +/- 2.3 ng/ml) were significantly higher (p < 0.001) in the epileptic group than in the group with febrile seizures (12.7 +/- 2.8 ng/ml), non-specific febrile illness (12.2 +/- 2.4 ng/ml), breath-holding spells (8.8 +/- 1.1 ng/ml) and normal controls (9.8 +/- 2.6 ng/ml). Mean serum cortisol levels were non-specifically elevated in children with epilepsy (32.8 +/- 2.2 ug/dl), febrile convulsion (34.2 +/- 4.1 ug/dl) and non-specific febril illness (30.6 +/- 2.4 ug/dl). Our observations suggest that elevated prolactin levels associated with afebrile epileptic seizures may help in differentiating epilepsy from febrile seizures and breath-holding spells. Cortisol levels appear to be non-specifically elevated in all stressful conditions.

Advances in the assessment of refractory epilepsy

The assessment of patients with refractory epilepsy presents both a challenge and an opportunity. The use of appropriate instruments to carefully and consistently measure a patient's seizure type and frequency, hormonal function, and medication side effects and the impact of those variables on quality of life ensures consistent, standardized assessment. A patient's epilepsy then can be classified as refractory based on any combination of factors that preclude a reasonably normal life-style by current practice standards, given the person's capabilities. Diagnostic studies and treatment strategies should address all significant adverse findings resulting from the assessment process. Accurate diagnosis of seizure type usually requires electroencephalographic (EEG) monitoring. Postictal hormonal assays and periodic measurements of estrogen and progesterone may be useful diagnostically in a selected group of patients. Awareness of a patient's compliance history, environmental stressors, and seizure triggers may reduce seizure frequency without a change in medication. For patients with medication intolerance, the usual strategy is to modify the medication regimen or treatment schedule to minimize side effects while maximizing seizure control and compliance. For most patients, monotherapy provides a greater therapeutic window than combination therapy. Devising an effective and safe therapeutic regimen is an ongoing process and can be lengthy depending on seizure type(s), frequency, and temporal pattern; anticonvulsant pharmacokinetics; drug interactions and side effects; patient's life-style; and other factors. Serial measurements of quality-of-life variables may assist in the process. Rapid strides have been recently made, and as the pace of new antiepileptic drug development quickens and surgical centers become more widely available, clinicians will need to redefine refractoriness as the expectations improve for patients with epilepsy.

Predictivity of plasma prolactin levels in differentiating epilepsy from pseudoseizures: a prospective study

The predictivity of raised plasma prolactin (PRL) concentrations in differentiating seizure from syncopal attack was prospectively assessed in all patients consecutively admitted to the Clinica Neurologica of Brescia, Italy in a 12-month period who fulfilled the criteria for either a seizure or syncopal attack. Postictal plasma prolactin concentration (P1) was assessed as soon as possible after the event. Three further assessments were performed: P2 was sampled 1 h after P1, P3, and P4 were sampled in the morning for the next 2 days. Patients who had had a seizure showed significantly increased P1 concentrations, when P1 was sampled within 60 min of the attack. In seizure patients assessed > 1 h after the event, P1 was not significantly different from either P2, P3, or P4. In patients who had had a syncopal attack, PRL concentration never increased. In patients assessed < or = 60 min after the seizure, cutoff criterion of P1 exceeding by +3 SD the mean calculated on P2, P3, and P4 yielded a positive predictive value of 89% and a negative predictive value of 61%. These findings confirm that plasma prolactin concentration is highly predictive of true epilepsy but barely predictive of pseudoseizures.

Serum prolactin response to thyrotropin-releasing hormone during status epilepticus

Determination of serum prolactin can help distinguish between epileptic and pseudo-epileptic attacks since generalized tonic-clonic and complex partial seizures frequently are accompanied by a transient rise in prolactin. In status epilepticus, however, serum prolactin levels are well within the normal range: cellular depletion due to the prolonged seizure activity has been suggested as a mechanism for this finding. The control of prolactin secretion is complex. Among several possible regulators, inhibitory dopamine and stimulatory thyrotropin-releasing hormone (TRH) may take part in the regulation of prolactin levels in connection with epileptic activity. There may be subpopulations of prolactin-producing cells that react differently in response to various regulators. A dopamine receptor blocker given during status epilepticus brings forth a distinct increase in prolactin levels. In order to add to the understanding of prolactin changes in connection with status epilepticus, we injected TRH i.v. during status epilepticus in seven consecutive patients. All patients had prolactin levels within the normal range (< 25 micrograms/l) before injection of TRH which resulted in at least a two-fold increase in prolactin levels. Our results contradict the hypothesis of cellular depletion of prolactin in connection with status epilepticus. The mechanism behind prolactin values within the normal range after prolonged seizure activity remains unknown.

Serum prolactin response to metoclopramide during status epilepticus

Transient elevation of serum prolactin frequently follows generalised tonic-clonic and complex partial seizures. However, the levels of prolactin during status epilepticus are not increased above the normal range. Exhaustion of central prolactin supplies has been proposed as a possible mechanism for the absence of prolactin increase during status epilepticus. To test this hypothesis we injected intravenous metoclopramide (10 mg) in eight consecutive patients with status epilepticus. One patient had generalised tonic-clonic status epilepticus. Seven patients had EEG-verified non-convulsive status epilepticus, consisting of one typical absence status, one atypical absence status and five complex partial status epilepticus. Metoclopramide raised the mean (SD) prolactin levels at least five-fold in all patients, from 5.8 (8.0) micrograms/l to 87.0 (39.0) micrograms/l, within 60 minutes after the injection. Thus the mechanism for low prolactin values in status epilepticus is not cellular depletion of stored prolactin, but more likely an altered regulation, presumably induced by prolonged seizure activity.

Calcification of the pineal gland: relationship to laterality of the epileptic foci in patients with complex partial seizures

The right and left temporal lobes differ from each other with respect to the rate of intrauterine growth, the timing of maturation, rate of aging, anatomical organization, neurochemistry, metabolic rate, electroencephalographic measures, and function. These functional differences between the temporal lobes underlies the different patterns of psychopathology and endocrine reproductive disturbances noted in patients with temporolimbic epilepsy. The right hemisphere has greater limbic and reticular connections than the left. Since the pineal gland receives direct innervation from the limbic system and the secretion of melatonin is influenced by an input from the reticular system, I propose that lesions in the right temporal lobe have a greater impact on pineal melatonin functions as opposed to those in the left dominant temporal lobe. Consequently, since calcification of the pineal gland is thought to reflect past secretory activity of the gland, I predicted a higher prevalence of pineal calcification (PC) in epileptic patients with right temporal lobe as opposed to those with left temporal lobe foci. To investigate this hypothesis, the prevalence of PC on CT scan was studied in a sample of 70 patients (43 men, 27 women, mean age: 29.2 years, range 9-58; SD = 10.1) with complex partial seizures, of whom 49 (70.0%) had a right temporal lobe focus. PC was present in 51 patients (72.8%) and was unrelated to any of the historical and demographic data surveyed. In the patients with a focus in the right temporal lobe, PC was present in 46 cases (93.8%) as compared to 5 of 21 patients (23.8%) with left temporal lobe foci.(ABSTRACT TRUNCATED AT 250 WORDS)

Hormones and epilepsy through the lifetime

Hormones influence brain function from gestation throughout life and may affect the seizure threshold by altering neuronal excitability. Estrogen enhances and progesterone diminishes neuronal excitability experimentally, whereas testosterone and corticosteroids have less consistent effects. Hormonal effects in the CNS also depend on the region of brain in which the hormone acts. Sites of action for most steroid hormones include the hypothalamus and limbic cortex, providing a mechanism for modulating behavior and endocrine function. Seizure patterns may change at certain life stages, perhaps as a result of alterations in hormones. At puberty, epilepsy and benign rolandic epilepsy often remit, while juvenile myoclonic and photosensitive epilepsy may arise. Other types of epilepsy do not respond predictably to events in the reproductive life or to advancing age. In some women, fluctuations in hormones over the menstrual cycle appear to increase seizure vulnerability, probably reflecting changes in relative amounts of estrogen and progesterone. Seizure patterns can be altered, for better or worse, during pregnancy. Whether this reflects the effects of hormones or changes in levels of antiepileptic drugs is not resolved. More information is needed about changes in established epilepsy at menopause and in the elderly. Better understanding of endocrine effects on seizures over a lifetime should lead to more effective epilepsy therapies.

Serum prolactin concentrations and epilepsy. A study which compares healthy subjects with a group of patients in presurgical evaluation and circadian variations with those related to seizures

In 20 healthy subjects (10 female and 10 male) and 17 patients undergoing presurgical epilepsy evaluation with intracranial EEG electrodes, circadian variations of serum prolactin (PRL) were measured. A comparison between the peak values found in normals with the postictal rises in patients, led us to consider 700 microU/ml to be the threshold of diagnostic value and the observed rises above this level to be all induced by seizures. In order to assess the clinical value of this threshold, PRL was measured postictally in a further 30 patients with epilepsy and in 11 patients with psychogenic seizures. In none of the latter group did PRL rises exceed 700 microU/ml, while they did so in 39% of the complex partial seizures and in 80% of the tonic-clonic seizures. There was no significant difference with respect to sex (a rise over 700 microU/ml in 42% in male and in 55% in female patients). Based on the findings in 17 patients investigated by means of intracranial electrodes, we were not able to establish different criteria for different focus localisations: in 66% of both temporal as well as frontal lobe seizures the 700 microU/ml level was exceeded. As a trend, in the period preceding an epileptic seizure we found a slightly decreasing PRL level, whereas in healthy persons the PRL concentrations gradually increased in the 40 minutes before the maximum spontaneous peak was reached.