A scoping review of hormonal clinical trials in menstrual cycle-related brain disorders: Studies in premenstrual mood disorder, menstrual migraine, and catamenial epilepsy

Cyclic variations in hormones during the normal menstrual cycle underlie multiple central nervous system (CNS)-linked disorders, including premenstrual mood disorder (PMD), menstrual migraine (MM), and catamenial epilepsy (CE). Despite this foundational mechanistic link, these three fields operate independently of each other. In this scoping review (N = 85 studies), we survey existing human research studies in PMD, MM, and CE to outline the exogenous experimental hormone manipulation trials conducted in these fields. We examine a broad range of literature across these disorders in order to summarize existing diagnostic practices and research methods, highlight gaps in the experimental human literature, and elucidate future research opportunities within each field. While no individual treatment or study design can fit every disease, there is immense overlap in study design and established neuroendocrine-based hormone sensitivity among the menstrual cycle-related disorders PMD, MM, and CE.

SCOPING REVIEW STRUCTURED SUMMARY

Background. The menstrual cycle can be a biological trigger of symptoms in certain brain disorders, leading to specific, menstrual cycle-linked phenomena such as premenstrual mood disorders (PMD), menstrual migraine (MM), and catamenial epilepsy (CE). Despite the overlap in chronicity and hormonal provocation, these fields have historically operated independently, without any systematic communication about methods or mechanisms.

OBJECTIVE

Online databases were used to identify articles published between 1950 and 2021 that studied hormonal manipulations in reproductive-aged females with either PMD, MM, or CE. We selected N = 85 studies that met the following criteria: 1) included a study population of females with natural menstrual cycles (e.g., not perimenopausal, pregnant, or using hormonal medications that were not the primary study variable); 2) involved an exogenous hormone manipulation; 3) involved a repeated measurement across at least two cycle phases as the primary outcome variable.

CHARTING METHODS

After exporting online database query results, authors extracted sample size, clinical diagnosis of sample population, study design, experimental hormone manipulation, cyclical outcome measure, and results from each trial. Charting was completed manually, with two authors reviewing each trial.

RESULTS

Exogenous hormone manipulations have been tested as treatment options for PMD (N = 56 trials) more frequently than MM (N = 21) or CE (N = 8). Combined oral contraceptive (COC) trials, specifically those containing drospirenone as the progestin, are a well-studied area with promising results for treating both PMDD and MM. We found no trials of COCs in CE. Many trials test ovulation suppression using gonadotropin-releasing hormone agonists (GnRHa), and a meta-analysis supports their efficacy in PMD; GnRHa have been tested in two MM-related trials, and one CE open-label case series. Finally, we found that non-contraceptive hormone manipulations, including but not limited to short-term transdermal estradiol, progesterone supplementation, and progesterone antagonism, have been used across all three disorders.

CONCLUSIONS

Research in PMD, MM, and CE commonly have overlapping study design and research methods, and similar effects of some interventions suggest the possibility of overlapping mechanisms contributing to their cyclical symptom presentation. Our scoping review is the first to summarize existing clinical trials in these three brain disorders, specifically focusing on hormonal treatment trials. We find that PMD has a stronger body of literature for ovulation-suppressing COC and GnRHa trials; the field of MM consists of extensive estrogen-based studies; and current consensus in CE focuses on progesterone supplementation during the luteal phase, with limited estrogen manipulations due to concerns about seizure provocation. We argue that researchers in any of these respective disciplines would benefit from greater communication regarding methods for assessment, diagnosis, subtyping, and experimental manipulation. With this scoping review, we hope to increase collaboration and communication among researchers to ultimately improve diagnosis and treatment for menstrual-cycle-linked brain disorders.

Progesterone and its derivatives for the treatment of catamenial epilepsy: A systematic review

OBJECTIVE

Catamenial epilepsy (CE) is defined as an increase in seizure frequency during specific phases of the menstrual cycle in women with epilepsy. The treatment usually includes a combination of non-hormonal and hormonal therapies. This systematic review summarizes the available data on the efficacy of progesterone and its derivates to treat CE.

METHODS

We performed a systematic search of the literature to identify studies reporting data on the use of progesterone and its derivatives (any type and dose) for the treatment of CE. The main outcome included the efficacy of progesterone and its derivatives on seizure frequency.

RESULTS

Nineteen articles (457 patients) were included; four were randomized controlled trials (two comparing progesterone vs placebo and two comparing norethisterone vs placebo). Progesterone was generally administered during the luteal phase (from day 15 to 25) or during perimenstrual exacerbations (from day 23 to 25), with an average dose of 10-30 mg/day to a maximum of 300 mg/day. The therapy, usually well tolerated, was ineffective in the randomized controlled trials; conversely, it was associated with an overall reduction in seizure frequency in case reports and uncontrolled studies.

CONCLUSIONS

Although data from uncontrolled studies suggest that hormone therapy with progesterone may be useful in the treatment of CE, its efficacy has not been demonstrated in controlled trials. The possible antiseizure effect of progesterone could be mediated by its active metabolite allopregnanolone, making the plasmatic measurement of these hormones mandatory to evaluate efficacy. Further randomized controlled trials should investigate the efficacy of progesterone and its derivatives, addressing these pharmacological issues.

Ferulic acid inhibits catamenial epilepsy through modulation of female hormones

Approximately 40% of women with epilepsy experience perimenstrual seizure exacerbation, referred to as catamenial epilepsy. These seizures result from cyclic changes in circulating progesterone and estradiol levels and there is no effective treatment for this form of intractable epilepsy. We artificially increased progesterone levels and neurosteroid levels (pseudo-pregnancy) in adult Swiss albino female mice (19-23 g) by injecting them with pregnant mares' serum gonadotropin (5 IU s.c.), followed by human chorionic gonadotropin (5 IU s.c.) after 46 h. After this, ferulic acid (25, 50, 100 mg/kg i.p.) treatment was given for 10 days. During treatment, progesterone, estradiol, and corticosterone levels were estimated in blood on days 1, 5, and 10. Neurosteroid withdrawal was induced by finasteride (50 mg/kg, i.p.) on treatment day 9. Twenty-four hours after finasteride administration (day 10 of treatment), seizure susceptibility was evaluated with the sub-convulsant pentylenetetrazol (PTZ) dose (40 mg/kg i.p.). Four to six hours after PTZ, animals were assessed for depression like phenotypes using tail-suspension test (TST). Four to six hours following TST, animals were euthanized, and discrete brain parts (cortex and hippocampus) were separated for estimation of norepinephrine, serotonin, and dopamine as well as glutamic acid decarboxylase (GAD) enzyme activity. PMSG and HCG treatment elevated progesterone and estradiol levels, assessed on days 1, 5, and 10 causing a state of pseudo-pregnancy. Treatment with finasteride increased seizure susceptibility and depression-like characteristics possibly due to decreased progesterone and elevated estrogen levels coupled with decreased monoamine and elevated corticosterone levels. Ferulic acid treatment, on the other hand, significantly decreased seizure susceptibility and depression like behavior, possibly because of increased progesterone, restored estradiol, corticosterone, monoamines, and GAD enzyme activity. We concluded anticonvulsant effect of ferulic acid in a mouse model of catamenial epilepsy, evidenced by favourable seizure attenuation and curative effect on the circulating progesterone, estradiol, and corticosterone levels along with restorative effect on GAD enzyme activity and monoamine levels.

Anticonvulsant Effect of Asparagus racemosus Willd. in a Mouse Model of Catamenial Epilepsy

Asparagus racemosus Willd. (Family Liliaceae), also known as female reproductive tonic, is traditionally used across the Sub-Himalayan region in Uttarakhand, India for treatment of epilepsy and disorders of female reproductive system. Therefore, in this study, we investigated the anticonvulsant effect of A. racemosus in a mouse model of catamenial epilepsy. We artificially increased progesterone and neurosteroid levels (a state of pseudo-pregnancy) in adult Swiss albino female mice by injecting pregnant mares' serum gonadotropin (PMSG) (5 IU s.c.), followed by human chorionic gonadotropin (HCG) (5 IU s.c.) after 46 h. In the following 10 days, A. racemosus treatment was given along with measurement of progesterone, estradiol, and corticosterone levels in the blood. Neurosteroid withdrawal was induced by finasteride (50 mg/kg, i.p.) on treatment day 9. Twenty-four hours after finasteride administration (day 10 of treatment), seizure susceptibility was evaluated with the sub-convulsant pentylenetetrazole (PTZ) dose (40 mg/kg i.p.). Four hours after PTZ, animals were assessed for depression like phenotypes followed by euthanasia and separation of brain parts (cortex and hippocampus). The results showed that PMSG and HCG treatment elevated progesterone and estradiol levels. Treatment with finasteride increased seizure susceptibility and depression due to decreased progesterone and elevated estrogen levels coupled with decreased monoamine and elevated corticosterone levels. A. racemosus treatment, on the other hand, significantly decreased seizure susceptibility and depression like behaviors, possibly because of increased progesterone, restored estradiol, corticosterone, and monoamine levels. We concluded that herbal formulations using A. racemosus root extracts may be used as monotherapy or adjuvant therapy along with available AEDs for the better and safe management of catamenial epilepsy as well as comorbid depression.

Effects of the Menstrual Cycle on Neurological Disorders

PURPOSE OF REVIEW

The menstrual cycle involves recurrent fluctuations in hormone levels and temperature via neuroendocrine feedback loops. This paper reviews the impact of the menstrual cycle on several common neurological conditions, including migraine, seizures, multiple sclerosis, stroke, and Parkinson's disease.

RECENT FINDINGS

The ovarian steroid hormones, estrogen and progesterone, have protean effects on central nervous system functioning that can impact the likelihood, severity, and presentation of many neurological diseases. Hormonal therapies have been explored as a potential treatment for many neurological diseases with varying degrees of evidence and success. Neurological conditions also impact women's reproductive health, and the cessation of ovarian function with menopause may also alter the course of neurological diseases. Medication selection must consider hormonal effects on metabolism and the potential for adverse drug reactions related to menstruation, fertility, and pregnancy outcomes. Novel medications with selective affinity for hormonal receptors are desirable. Neurologists and gynecologists must collaborate to provide optimal care for women with neurological disorders.

Features of Menstruation and Menstruation Management in Individuals with Rett Syndrome

STUDY OBJECTIVE

To describe features of menstruation, menstrual-related symptoms, and menstrual management in females with Rett syndrome (RTT) to help develop a clinical approach to these parameters in RTT.

DESIGN

Retrospective cross-sectional chart review and prospective survey.

SETTING

Cincinnati Children's Hospital Medical Center, Rett Syndrome and Related Spectrum Disorders Clinic.

PARTICIPANTS

Females with RTT (12-55 years of age) and their caregivers.

MAIN OUTCOME MEASURES

Descriptive data on features of menstruation and menstrual-related symptoms in individuals with Rett syndrome; prevalence, types, reason for use/discontinuation, and efficacy of hormonal treatment in females with RTT.

RESULTS

Age at menarche, menstrual cycle length, and menstrual period length in females with RTT are comparable to those in typically developing females and females with other neurodevelopmental disabilities. Dysmenorrhea and emotional lability are common menstrual cycle-related changes among females with RTT; 22.1% of participants also reported catamenial seizures. Oral progestin, combined oral contraceptive pill, and depot-medroxyprogesterone acetate (DMPA) were effectively used to suppress or regulate menstruation and to manage menstrual-related symptoms.

CONCLUSIONS

Characteristics of menstruation in females with RTT are comparable to those of typically developing females, with the exception of increase in catamenial seizure activity. Hormonal treatments are used for management of menstruation, dysmenorrhea, and seizures. Choice of hormonal treatment is influenced by bone health and immobility in females with RTT.

Progesterone modulates neuronal excitability bidirectionally

Progesterone acts on neurons directly by activating its receptor and through metabolic conversion to neurosteroids. There is emerging evidence that progesterone exerts excitatory effects by activating its cognate receptors (progesterone receptors, PRs) through enhanced expression of α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptors (AMPARs). Progesterone metabolite 5α,3α-tetrahydro-progesterone (allopregnanolone, THP) mediates its anxiolytic and sedative actions through the potentiation of synaptic and extrasynaptic γ-aminobutyric acid type-A receptors (GABAARs). Here, we review progesterone's neuromodulatory actions exerted through PRs and THP and their opposing role in regulating seizures, catamenial epilepsy, and seizure exacerbation associated with progesterone withdrawal.

The interactions between reproductive hormones and epilepsy

There are complex interactions between hormones, epilepsy, and antiepileptic drugs (AEDs). While there is ample evidence that hormones influence epilepsy, it is also apparent that epileptic activity influences hormones in both women and men. In addition, AEDs may disturb endocrine function. The clinical importance of these interactions is primarily related to the effects on reproductive hormones, which is the focus of this article. Reproductive endocrine dysfunction is common among women and men with epilepsy. Menstrual disorders, polycystic ovaries, and infertility have been described among women with epilepsy, while reduced potency and sperm abnormalities have been found in men. Sexual problems and endocrine changes have been frequently described in both sexes. Epilepsy and AEDs can target a number of substrates to impact hormone levels. These include the limbic system, hypothalamus, pituitary, peripheral endocrine glands, liver, and adipose tissue. AEDs may also alter the synthesis of steroids and binding proteins, as well as hormone metabolism, and produce direct gonadal effects.

Neurosteroid regulation of GABAA receptors: A role in catamenial epilepsy

The female reproductive hormones progesterone and estrogen regulate network excitability. Fluctuations in the circulating levels of these hormones during the menstrual cycle cause frequent seizures during certain phases of the cycle in women with epilepsy. This seizure exacerbation, called catamenial epilepsy, is a dominant form of drug-refractory epilepsy in women of reproductive age. Progesterone, through its neurosteroid derivative allopregnanolone, increases γ-aminobutyric acid type-A receptor (GABAR)-mediated inhibition in the brain and keeps seizures under control. Catamenial seizures are believed to be a neurosteroid withdrawal symptom, and it was hypothesized that exogenous administration of progesterone to maintain its levels high during luteal phase will treat catamenial seizures. However, in a multicenter, double-blind, phase III clinical trial, progesterone treatment did not suppress catamenial seizures. The expression of GABARs with reduced neurosteroid sensitivity in epileptic animals may explain the failure of the progesterone clinical trial. The expression of neurosteroid-sensitive δ subunit-containing GABARs is reduced, and the expression of α4γ2 subunit-containing GABARs is upregulated, which alters the inhibition of dentate granule cells in epilepsy. These changes reduce the endogenous neurosteroid control of seizures and contribute to catamenial seizures.

Catamenial epilepsy: A missed cause of refractory seizure in young women

Catamenial epilepsy refers to changes in the frequency of seizures over the course of the menstrual cycle. A thorough history and detailed review of the patient's seizure diary are imperative to classify the seizures accurately and select the most appropriate antiepileptic treatment. As catamenial epilepsy rarely responds to antiepileptic medications, the physician should regularly revise the treatment plan of the women with epilepsy that is refractory to the current treatment. We describe the case of a 34-year-old single woman who presented with refractory seizures.

The Effect of Menstrual Issues on Young Women with Angelman Syndrome

STUDY OBJECTIVE

To characterize menstrual health issues and their effect in young women with Angelman syndrome (AS). Our secondary objective was to compare them with young women with autism spectrum disorders (ASDs).

DESIGN

Cross-sectional convenience sample survey.

SETTING

An institutional review board-approved Web-based survey of young female members of the Angelman Syndrome Foundation.

PARTICIPANTS

Caregivers of young women with AS, aged 12-25 years.

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

Symptom characterization and effect of menses on young women with AS.

RESULTS

Menstrual and premenstrual symptoms were common among young women with AS, but infrequently caused problems at home or school. Less than half of the subjects used hormones to control their flow. Of those who used hormones, 75% used them continuously. Caregivers were satisfied with their method to control periods. Girls with seizures were more likely to use hormonal methods to control menses than those without seizures. Menstrual-associated morbidity in young women with ASD and AS was fairly similar, but with greater morbidity in the ASD group than in the AS group. However, girls with AS had more problems with menstrual hygiene with almost all of them requiring full assistance for managing hygiene.

CONCLUSION

In this group of young women with AS, who have moderate to severe neurodevelopmental disabilities and cannot manage their own hygiene, menstruation is not associated with significant problems. Menstrual management by hormones is used by less than half. When hormonal therapy is used, it is most commonly used continuously to suppress menses.

The neuroendocrine basis of sex differences in epilepsy

Epilepsy affects people of all ages and both genders. Sex differences are well known in epilepsy. Seizure susceptibility and the incidence of epilepsy are generally higher in men than women. In addition, there are gender-specific epilepsies such as catamenial epilepsy, a neuroendocrine condition in which seizures are most often clustered around the perimenstrual or periovulatory period in adult women with epilepsy. Changes in seizure sensitivity are also evident at puberty, pregnancy, and menopause. Sex differences in seizure susceptibility and resistance to antiseizure drugs can be studied in experimental models. An improved understanding of the neuroendocrine basis of sex differences or resistance to protective drugs is essential to develop targeted therapies for sex-specific seizure conditions. This article provides a brief overview of the current status of sex differences in seizure susceptibility and the potential mechanisms underlying the gender differences in seizure sensitivity.

A Treatment Approach to Catamenial Epilepsy

OPINION STATEMENT

The cyclic hormonal underpinnings of catamenial seizure exacerbations are consistent with the neurophysiologic activity of estrogen and progesterone. For women with catamenial epilepsy who have regular menses, intermittent treatment approaches may be utilized. These interventions are targeted at adding or increasing anti-seizure treatments during established vulnerable days of the menstrual cycle, such as perimenstrually (C1 pattern), at ovulation (C2 pattern), and during the luteal phase (C3 pattern). The single large study of natural progesterone treatment showed benefit for women with clear perimenstrual seizure exacerbations (C1 pattern), but not for subjects with other catamenial patterns or for randomized women with epilepsy of reproductive age who did not have catamenial seizure exacerbations. In this protocol, natural progesterone was given at a high dose during the luteal phase and was generally well tolerated. Other intermittent cyclic treatments include benzodiazepine use, increasing the dose of an anti-seizure drug already in use, or acetazolamide. For women with irregular menses, or those in which the intermittent cyclic treatments are not effective, pharmacologically stopping the menstrual cycle altogether by using synthetic hormones such as medroxyprogesterone (Depo-Provera) or sustained oral contraceptives may be considered.

Association between estrus and onset of seizures in dogs with idiopathic epilepsy

BACKGROUND

Catamenial epilepsy in humans is defined as changes in seizure frequency over the course of the menstrual cycle. Three hormonally based patterns of seizure exacerbation have been determined.

OBJECTIVES

The aim of this study was to evaluate whether there is an association between onset of seizures and the estrous cycle in intact bitches with presumptive idiopathic epilepsy and whether a pattern to the onset of seizures could be recognized.

ANIMALS

Forty-five intact female dogs from a hospital population with a presumptive diagnosis of idiopathic epilepsy.

METHODS

In a retrospective study, the database of a small animal hospital in Sweden was searched for medical records of intact female dogs diagnosed with epilepsy or seizures. The stage of the estrous cycle as reported either by the owner or the veterinarian at the time of the first seizure was noted.

RESULTS

Of the 45 dogs with idiopathic epilepsy, 17 (38%) had their first seizure when in heat and six dogs (13%) had their first seizure 1-3 months after heat. Nine dogs (20%) had seizures reoccurring in relation to their estrous cycle.

CONCLUSIONS AND CLINICAL IMPORTANCE

These findings suggest an association between estrus and onset of seizures in intact bitches with presumptive idiopathic epilepsy. Two hormonally based patterns could be recognized: one during heat and one during a specific time point at the end of diestrus. This could be explained by the proconvulsive effects of estrogen or loss of protective effect against seizures of progesterone, respectively.

Neurosteroids and their role in sex-specific epilepsies

Neurosteroids are involved in sex-specific epilepsies. Allopregnanolone and related endogenous neurosteroids in the brain control excessive neuronal excitability and seizure susceptibility. Neurosteroids activate GABA-A receptors, especially extrasynaptic αγδ-GABA-A receptor subtypes that mediate tonic inhibition and thus dampen network excitability. Our studies over the past decade have shown that neurosteroids are broad-spectrum anticonvulsants and confer seizure protection in various animal models. Neurosteroids also exert antiepileptogenic effects. There is emerging evidence on a critical role for neurosteroids in the pathophysiology of the sex-specific forms of epilepsies such as catamenial epilepsy, a menstrual cycle-related seizure disorder in women. Catamenial epilepsy is a neuroendocrine condition in which seizures are clustered around specific points in the menstrual cycle, most often around the perimenstrual or periovulatory period. Apart from ovarian hormones, fluctuations in neurosteroid levels could play a critical role in this gender-specific epilepsy. Neurosteroids also regulate the plasticity of synaptic and extrasynaptic GABA-A receptors in the hippocampus and other regions involved in epilepsy pathology. Based on these studies, we proposed a neurosteroid replacement therapy for catamenial epilepsy. Thus, neurosteroids are novel drug targets for pharmacotherapy of epilepsy.

Progesterone therapy in women with intractable catamenial epilepsy

Background:

Catamenial epilepsy is a kind of epilepsy, known in this name, when the periodicity of the exacerbation of the seizure is in association with menstural cycle. The present study examined the progesterone effectiveness as a complementary treatment in women with intractable catamenial epilepsy.

Materials and Methods:

The present study was conducted as a double-blind randomized controlled trial on 38 women with intractable catamenial epilepsy. Patients were assessed in two groups: The case group received in addition to AEDs, two (Mejestrol) 40 mg progesterone tablets in the second half of the cycle from 15^th to 25^th day. And the control group received in addition to AEDs, two placebo tablets daily. Age, BMI, epilepsy duration, types of the drugs used, progesterone level, and the number of the seizures in 3 months before and after the study were compared.

Results:

Based on the results of which there was no statistically significant difference in regard to age, BMI, epilepsy duration, types of the drugs used, progesterone level between the case and the control groups (P-value > 0.05). The number of the seizures after treatment has significantly decreased compared to before-treatment state. The degree of decreasing in the case group receiving the progesterone was higher than in the control group receiving the placebo. The difference, thus, is significant, based on statistical tests (P-value = 0.024).

Conclusion:

Based on the findings of this study using progesterone in women with intractable catamenial epilepsy has a significant effect on the degree of decreasing in the number of the seizures.