Stress sensitivity of childhood epilepsy is related to experienced negative life events

Child with epilepsy in school environment - The development of a conceptual model

OBJECTIVE

The aim of this qualitative study is to develop a conceptual model for the school life of the children with epilepsy based on grounded theory methodological framework.

METHODOLOGY

A total of 20 children with epilepsy participated in the semi-structured interviews. Inclusion criteria were age of 8-15 years, IQ higher than 70, duration of epilepsy of at least of two years and attendance of mainstream schools. 15 children had never seizure in school and 16 of them have not had a seizure in last 12 months. Qualitative research data was processed based on grounded theory with open coding leading consecutively to several main categories, axial coding establishing connections between individual categories, and finally selective coding resulting in one central category which was the core of the developed conceptual model.

RESULTS

Eight main categories were identified during open coding: type of epilepsy and its management, sources of stress at school, adaptive responses to stressors, safe school environment in relation to (a) epilepsy and (b) learning, family support, stability of experience and behavior, and positive self-concept. Axial and selective coding resulted in establishment of Adaptive responses to stressors as the central category which is in the developed conceptual model determined by relevant external and internal factors as well as the sources enabling effective adaptation.

CONCLUSIONS

The presented research emphasize the importance of adaptive responses to stressors in the school environment among children with epilepsy which may be useful in counselling focused on how to avoid or successfully manage possible traumatizing experience related with epilepsy in this group.

Factors associated with stress-related symptoms among people with epilepsy in Ethiopia, a cross-sectional study

Introduction

Stress is a common psychological problem present in people with epilepsy and has a serious impact on the health-related satisfaction of people with epilepsy and their cohabiters. This study aimed to assess the magnitude and related factors of stress.

Methods

A hospital-based cross-sectional study was carried out among 301 systematically chosen people with epilepsy. The seven stress-related items of the Depression, Anxiety, and Stress -21 questionnaire was used to measure stress. Data were entered using Epi Info and analyzed by SPSS version 25. Predictors with a p-value < 0.20 in the bivariate logistic regression were transferred into the multivariate model. A p-value of less than 0.05 was viewed as statistically significant.

Result

The prevalence of stress symptoms in this study was 23.9%. Daily labor occupational status with Adjusted Odds ratio [(AOR) = 0.042, 95% CI: 0.004, 0.469], onset of illness at the age of 18 years and above (AOR = 0.188, 95% CI: 0.046, 0.771), perceived stigma (AOR = 3.320, 95% CI: 1.345, 8.200), the presence of anxiety symptoms (AOR = 8.275, 95% CI: 3.345, 20.471), and belief that the condition is untreatable (AOR = 6.360, 95% CI: 1.647, 24.562) were significantly associated factors.

Conclusion

The occurrence of stress was high, and it reinforced that there is a requisite for the identification and handling of stress-related symptoms among people with epilepsy.

Noradrenergic stimulation of α1 adrenoceptors in the medial prefrontal cortex mediates acute stress-induced facilitation of seizures in mice

Stress is one of the critical facilitators for seizure induction in patients with epilepsy. However, the neural mechanisms underlying this facilitation remain poorly understood. Here, we investigated whether noradrenaline (NA) transmission enhanced by stress exposure facilitates the induction of medial prefrontal cortex (mPFC)-originated seizures. In mPFC slices, whole-cell current-clamp recordings revealed that bath application of picrotoxin induced sporadic epileptiform activities (EAs), which consisted of depolarization with bursts of action potentials in layer 5 pyramidal cells. Addition of NA dramatically shortened the latency and increased the number of EAs. Simultaneous whole-cell and field potential recordings revealed that the EAs are synchronous in the mPFC local circuit. Terazosin, but not atipamezole or timolol, inhibited EA facilitation, indicating the involvement of α₁ adrenoceptors. Intra-mPFC picrotoxin infusion induced seizures in mice in vivo. Addition of NA substantially shortened the seizure latency, while co-infusion of terazosin into the mPFC inhibited the effect of NA. Finally, acute restraint stress shortened the latency of intra-mPFC picrotoxin infusion-induced seizures, whereas prior infusion of terazosin reversed this stress-induced shortening of seizure latency. Our findings suggest that stress facilitates the induction of mPFC-originated seizures via NA stimulation of α₁ adrenoceptors.

The impact of early-life environment on absence epilepsy and neuropsychiatric comorbidities

This review discusses the long-term effects of early-life environment on epileptogenesis, epilepsy, and neuropsychiatric comorbidities with an emphasis on the absence epilepsy. The WAG/Rij rat strain is a well-validated genetic model of absence epilepsy with mild depression-like (dysthymia) comorbidity. Although pathologic phenotype in WAG/Rij rats is genetically determined, convincing evidence presented in this review suggests that the absence epilepsy and depression-like comorbidity in WAG/Rij rats may be governed by early-life events, such as prenatal drug exposure, early-life stress, neonatal maternal separation, neonatal handling, maternal care, environmental enrichment, neonatal sensory impairments, neonatal tactile stimulation, and maternal diet. The data, as presented here, indicate that some early environmental events can promote and accelerate the development of absence seizures and their neuropsychiatric comorbidities, while others may exert anti-epileptogenic and disease-modifying effects. The early environment can lead to phenotypic alterations in offspring due to epigenetic modifications of gene expression, which may have maladaptive consequences or represent a therapeutic value. Targeting DNA methylation with a maternal methyl-enriched diet during the perinatal period appears to be a new preventive epigenetic anti-absence therapy. A number of caveats related to the maternal methyl-enriched diet and prospects for future research are discussed.

Scorpion Envenomation of Lactating Rats Decreases the Seizure Threshold in Offspring

Few data are available in the literature describing the long-term effects of envenoming in the perinatal period. In this study, the relationship between envenoming of lactating rats and possible behavioral changes in the mother and in her offspring were investigated. Lactating Wistar rats received a single dose of T. serrulatus crude venom on postnatal days 2 (V2), 10 (V10) or 16 (V16), and had their maternal behavior evaluated. The seizure threshold was evaluated in adulthood offspring. A decrease in maternal care during envenoming was observed in V2 and V10 groups. The retrieval behavior was absent in the V2 group, and a lower seizure threshold in the adult offspring of all groups was observed. During envenoming, mothers stayed away from their offspring for a relatively long time. Maternal deprivation during the early postnatal period is one of the most potent stressors for pups and could be responsible, at least in part, for the decrease in the convulsive threshold of the offspring since stress is pointed to as a risk factor for epileptogenesis. Furthermore, the scorpionic accident generates an intense immune response, and inflammation in neonates increases the susceptibility to seizures in adulthood. Therefore, maternal envenoming during lactation can have adverse effects on offspring in adulthood.

Psychological Distress, Somatic Complaints, and Their Relation to Negative Psychosocial Factors in a Sample of Swedish High School Students

Background: Adolescence is a period in life characterized by major neurobiological, physiological, and psychological changes. Those changes may give rise to worsened mental health and an increased prevalence of somatic complaints combined with a negative psychosocial environment. Rapid changes in society, which may also affect young people in several ways, call for a renewed screening of today's adolescents' mental and somatic well-being. Aim: The present study's primary aim was to measure the level of self-rated psychological distress and the prevalence of somatic complaints in a sample of Swedish high school students. As a secondary aim, it identifies gender-specific patterns and examines mental and somatic health in relation to negative psychosocial factors (such as parental alcohol use problems or the experience of physical or psychological abuse). Method: Two hundred and eighty-seven Swedish high school students completed a survey including the Brief Symptom Inventory (BSI) and a questionnaire about the presence of defined somatic complaints. In order to examine the relationship between negative psychosocial factors and mental and somatic health, three groups were formed: those reporting (i) parental substance use problems, (ii) previous experience of abuse, (iii) none of these problems. Results: The majority of the Swedish high-school students (>80%) reported no or only a few problems with psychological distress and no or only one somatic complaint. Female students disclosed a significantly higher psychological distress level captured by each BSI domain. The number of somatic complaints was similarly distributed between the genders. The students rarely reported parental substance use problems, but almost 40% of the male and 50% of the female students indicated the experience of physical and/or psychological abuse. Such negative psychosocial circumstances were related to an increased level of anxiety in the male and an increased general level of psychological distress in female students. Conclusions: The study confirmed female students' higher psychological distress level. Gender differences in the type of somatic complaints, but not in the number were detected. The experience of physical and/or psychological abuse was found to significantly worsen psychological distress in students of both genders.

Past Trauma Is Associated With a Higher Risk of Experiencing an Epileptic Seizure as Traumatic in Patients With Pharmacoresistant Focal Epilepsy

Objective: The present study aimed to evaluate the prevalence of traumatic experienced seizures (TES) and of postepileptic seizure PTSD (PS-PTSD) in patients with pharmacoresistant focal epilepsy and to explore the determining factors of TES.

Methods: We conducted an observational study enrolling 107 adult refractory epilepsy patients. We used the DSM-5 criteria of traumatic events and PTSD to define TES and PS-PTSD. We assessed all traumatic life events unrelated to epilepsy, general and specific psychiatric comorbidities, and quality of life.

Results: Nearly half (n = 48) of the 107 participants reported at least one TES (44.85%). Among these, one-third (n = 16) developed PS-PTSD. The TES group was more likely to experience traumatic events unrelated to epilepsy (p < 0.001), to have generalized anxiety disorder (p = 0.019), and to have specific psychiatric comorbidities [e.g., interictal dysphoric disorder (p = 0.024) or anticipatory anxiety of seizures (p = 0.005)]. They reported a severe impact of epilepsy on their life (p = 0.01). The determining factors of TES according to the multifactorial model were the experience of trauma (p = 0.008), a history of at least one psychiatric disorder (p = 0.03), and a strong tendency toward dissociation (p = 0.03).

Significance: Epileptic seizures may be a traumatic experience in some patients who suffer from pharmacoresistant epilepsy and may be the source of the development of PS-PTSD. Previous trauma unrelated to epilepsy and psychiatric history are determining factors of TES. These clinical entities should be explored systematically.

Factors Associated with Good Seizure Control in Patients on Valproic Acid

Objective

This study aims to generate a reference range for valproic acid (VPA) in this cohort and determine the factors associated with good seizure control in patients taking this drug.

Materials and Methods

We conducted a prospective, cohort, observational study among patients with epilepsy who received VPA treatment at Hospital Kuala Lumpur. The patients were considered to have good control if they had a 50% or higher seizure reduction in the one-year study period compared with the previous year. The VPA reference range was generated from those patients who had good control and whose drug concentration values were available. Multiple logistic regression analysis with a backward likelihood ratio method was applied to assess the predicting factors for good seizure control.

Results

A total of 242 patients were recruited and followed up for one year. The VPA reference range was determined to be 40-85 mg/L. After multivariate analysis, significant predictive variables for good control were monotherapy [adjusted OR 4.74, 95% CI: 2.258, 9.947, p<0.001], non-smoking [adjusted OR 3.23, 95% CI: 1.099, 9.473, p=0.033], normal brain imaging results [adjusted OR 5.83, 95% CI: 2.507, 13.552, p<0.001], and the absence of stress [adjusted OR 19.98, 95% CI: 9.255, 42.764, p<0.001].

Conclusion

Monotherapy, non-smoking, normal brain imaging results, and the absence of stress are predictive of good seizure control in patients on VPA. However, a serum concentration of VPA in the reference range failed to predict good seizure control.

Mechanisms of Psychiatric Comorbidities in Epilepsy

Psychiatric illnesses, including depression and anxiety, are highly comorbid with epilepsy (for review see Josephson and Jetté (Int Rev Psychiatry 29:409-424, 2017), Salpekar and Mula (Epilepsy Behav 98:293-297, 2019)). Psychiatric comorbidities negatively impact the quality of life of patients (Johnson et al., Epilepsia 45:544-550, 2004; Cramer et al., Epilepsy Behav 4:515-521, 2003) and present a significant challenge to treating patients with epilepsy (Hitiris et al., Epilepsy Res 75:192-196, 2007; Petrovski et al., Neurology 75:1015-1021, 2010; Fazel et al., Lancet 382:1646-1654, 2013) (for review see Kanner (Seizure 49:79-82, 2017)). It has long been acknowledged that there is an association between psychiatric illnesses and epilepsy. Hippocrates, in the fourth-fifth century B.C., considered epilepsy and melancholia to be closely related in which he writes that "melancholics ordinarily become epileptics, and epileptics, melancholics" (Lewis, J Ment Sci 80:1-42, 1934). The Babylonians also recognized the frequency of psychosis in patients with epilepsy (Reynolds and Kinnier Wilson, Epilepsia 49:1488-1490, 2008). Despite the fact that the relationship between psychiatric comorbidities and epilepsy has been recognized for thousands of years, psychiatric illnesses in people with epilepsy still commonly go undiagnosed and untreated (Hermann et al., Epilepsia 41(Suppl 2):S31-S41, 2000) and systematic research in this area is still lacking (Devinsky, Epilepsy Behav 4(Suppl 4):S2-S10, 2003). Thus, although it is clear that these are not new issues, there is a need for improvements in the screening and management of patients with psychiatric comorbidities in epilepsy (Lopez et al., Epilepsy Behav 98:302-305, 2019) and progress is needed to understand the underlying neurobiology contributing to these comorbid conditions. To that end, this chapter will raise awareness regarding the scope of the problem as it relates to comorbid psychiatric illnesses and epilepsy and review our current understanding of the potential mechanisms contributing to these comorbidities, focusing on both basic science and clinical research findings.

A longitudinal study on the effects of psychological stress on proteinuria in childhood steroid-sensitive nephrotic syndrome

OBJECTIVE

Steroid-sensitive nephrotic syndrome (SSNS) in children is often complicated by one or more relapses, as manifested by the appearance of proteinuria. Besides health-related triggers, psychological stress might be related to relapse. This longitudinal study examined the link between perceived stress, emotional valence (feeling happy vs. unhappy) and daily reported proteinuria, and investigated the temporal relation between stressful events and proteinuria.

METHOD

Sixteen children (4-13 years) diagnosed with SSNS were included. Patients kept an online diary for an average of 124 days, wherein they reported proteinuria (n = 1985 urine samples), perceived stress, emotional valence, medication use and health complaints. Stressful days were determined at the start of the study. Using multilevel analysis, the following associations were tested: (1) the relation between perceived stress, emotional valence and proteinuria, and (2) the temporal relation between stressful days and proteinuria.

RESULTS

Appearance of proteinuria was reported in 410/1985 urine samples. Perceived stress and not emotional valence significantly predicted proteinuria (95% CI [0.11, 0.27]), even five days later. There was a significant temporal association between stressful days and proteinuria (95% CI [0.22, 1.14]). The effect sizes of these associations were small, f = 0.04 and f = 0.12, respectively.

CONCLUSIONS

Our findings suggest that psychological stress may trigger proteinuria in children with SSNS. Future research in larger samples is needed to support our findings.

Somatic health and its association with negative psychosocial factors in a sample of Moroccan adolescents

Background:

Adolescence is a distinct developmental phase characterized by multiple physical and psychological changes and by an increased vulnerability to somatic and mental health problems. These risk and vulnerability factors are part of a complex biopsychosocial matrix, encompassing multiple factors, such as inherited biological determinants and psychological, societal, and cultural influences, which affect an adolescent’s overall wellbeing. In Morocco, similar to other developing countries, adolescents (young people aged from 15 to 19 years) constitute a substantial proportion of the population (almost 9%). However, studies about adolescents’ health in developing countries are scarce. In this study, we describe adolescents’ somatic health in a sample of high school students from the city of Tetouan, Morocco, and investigate how negative psychosocial factors, such as parental alcohol use problems and/or the experience of abuse, may influence them.

Methods:

The study sample included 655 adolescents (315 boys and 340 girls, M = 16.64 years, range = 15–18 years) from conviniently selected classes of four high schools in the city of Tetouan in Morocco. The students responded to a survey that assessed the prevalence of somatic complaints/disorders. They also indicated whether they had ever experienced physical and/or psychological abuse and whether they had parents with alcohol use problems.

Results:

More than half of the adolescents suffered from headaches and one-third had substantial problems with diarrhea or constipation. Both problems were more common in female students. The third most frequent somatic problem, affecting one in four in both genders, was allergy. Almost one-third of Moroccan adolescents (significantly more boys than girls; p = 0.004) reported no somatic complaints. In adolescents who reported parental alcohol use problems and/or experience of physical and/or psychological abuse, the prevalence of several somatic complaints (epilepsy, migraine, headache, diarrhea/constipation, gluten intolerance, allergy, and skin or thyroid disease) increased highly significantly compared to the adolescents who reported no such psychosocial environmental factors.

Conclusion:

The results suggest that only 3 in 10 urban-living Moroccan adolescents are free of somatic complaints, while the majority suffer from some somatic problems, most often headaches and diarrhea/constipation. The association of certain negative psychosocial factors with adolescents’ somatic health suggests the need of a holistic approach to the treatment of affected adolescents.

Hyperthermia-induced seizures followed by repetitive stress are associated with age-dependent changes in specific aspects of the mouse stress system

Stress is among the most frequently self-reported factors provoking epileptic seizures in children and adults. It is still unclear, however, why some people display stress-sensitive seizures and others do not. Recently, we showed that young epilepsy patients with stress-sensitive seizures exhibit a dysregulated hypothalamic-pituitary-adrenal (HPA)-axis. Most likely, this dysregulation gradually develops, and is triggered by stressors occurring early in life (early-life stress [ELS]). ELS may be particularly impactful when overlapping with the period of epileptogenesis. To examine this in a controlled and prospective manner, the present study investigated the effect of repetitive variable stressors or control treatment between postnatal day (PND) 12 and 24 in male mice exposed on PND10 to hyperthermia (HT)-induced prolonged seizures (control: normothermia). A number of peripheral and central indices of HPA-axis activity were evaluated at pre-adolescent and young adult age (ie, at PND25 and 90, respectively). At PND25 but not at PND90, body weight gain and absolute as well as relative (to body weight) thymus weight were reduced by ELS (vs control), whereas relative adrenal weight was enhanced, confirming the effectiveness of the stress treatment. Basal and stress-induced corticosterone levels were unaffected, though, by ELS at both ages. HT by itself did not affect any of these peripheral markers of HPA-axis activity, nor did it interact with ELS. However, centrally we did observe age-specific interaction effects of HT and ELS with regard to hippocampal glucocorticoid receptor mRNA expression, neurogenesis with the immature neurone marker doublecortin and the number of hilar (ectopic) granule cells using Prox1 staining. This lends some support to the notion that exposure to repetitive stress after HT-induced seizures may dysregulate central components of the stress system in an age-dependent manner. Such dysregulation could be one of the mechanisms conferring higher vulnerability of individuals with epilepsy to develop seizures in the face of stress.

Corticosteroids and the brain

The brain is continuously exposed to varying levels of adrenal corticosteroid hormones such as corticosterone in rodents and cortisol in humans. Natural fluctuations occur due to ultradian and circadian variations or are caused by exposure to stressful situations. Brain cells express two types of corticosteroid receptors, i.e. mineralocorticoid and glucocorticoid receptors, which differ in distribution and affinity. These receptors can mediate both rapid non-genomic and slow gene-mediated neuronal actions. As a consequence of these factors, natural (e.g. stress-induced) shifts in corticosteroid level are associated with a complex mosaic of time- and region-dependent changes in neuronal activity. A series of experiments in humans and rodents have revealed that these time- and region-dependent cellular characteristics are also reflected in distinct cognitive patterns after stress. Thus, directly after a peak of corticosteroids, attention and vigilance are increased, and areas involved in emotional responses and simple behavioral strategies show enhanced activity. In the aftermath of stress, areas involved in higher cognitive functions become activated allowing individuals to link stressful events to the specific context and to store information for future use. Both phases of the brain's response to stress are important to face a continuously changing environment, promoting adaptation at the short as well as long term. We argue that a balanced response during the two phases is essential for resilience. This balance may become compromised after repeated stress exposure, particularly in genetically vulnerable individuals and aggravate disease manifestation. This not only applies to psychiatric disorders but also to neurological diseases such as epilepsy.

A Comprehensive Overview on Stress Neurobiology: Basic Concepts and Clinical Implications

Stress is recognized as an important issue in basic and clinical neuroscience research, based upon the founding historical studies by Walter Canon and Hans Selye in the past century, when the concept of stress emerged in a biological and adaptive perspective. A lot of research after that period has expanded the knowledge in the stress field. Since then, it was discovered that the response to stressful stimuli is elaborated and triggered by the, now known, stress system, which integrates a wide diversity of brain structures that, collectively, are able to detect events and interpret them as real or potential threats. However, different types of stressors engage different brain networks, requiring a fine-tuned functional neuroanatomical processing. This integration of information from the stressor itself may result in a rapid activation of the Sympathetic-Adreno-Medullar (SAM) axis and the Hypothalamus-Pituitary-Adrenal (HPA) axis, the two major components involved in the stress response. The complexity of the stress response is not restricted to neuroanatomy or to SAM and HPA axes mediators, but also diverge according to timing and duration of stressor exposure, as well as its short- and/or long-term consequences. The identification of neuronal circuits of stress, as well as their interaction with mediator molecules over time is critical, not only for understanding the physiological stress responses, but also to understand their implications on mental health.

Stress, seizures, and epilepsy: Patient narratives

In epilepsy, individual seizures can be triggered by a variety of external and internal stimuli. One of the most common trigger factors reported by patients is stress. However prevalent, stress-related triggering of episodes seems underappreciated in epilepsy for various reasons, and its misinterpretation often leads to other diagnoses, e.g., psychogenic nonepileptic seizures (PNES) or normal reactions. This article illustrates the significant role of stress as a seizure-provoking factor by referring to nine patient narratives. From this perspective, it appears that there are characteristic patterns of stress triggering, e.g., stress-induced sleep disruption, forms of acute stress, or relaxation after stress. Sometimes seizures are mistaken as symptoms of stress. Patient narratives contain interesting clues relating reports about stress and seizure histories to different epilepsy syndromes as well as nonepileptic episodes in a way that can strongly support the diagnostic process. A narrative approach is particularly valuable in this context. Therefore, accounts of stress triggering in seizures and other episodes should not be neglected, but rather taken seriously, sought and actively explored as a crucial element when taking clinical histories in patients with episodic attacks.

Clinical characterization of the pre-ictal state in the pediatric population: A caretaker's perspective

The unpredictability of seizures causes distress to patients with epilepsy and their caretakers. To date, no studies have explored seizure prediction specifically in the pediatric population. If the period of time preceding a seizure can be reliably identified, either by child or caretaker, there may be a role for pre-emptive interventions. The aim of this study was to investigate caretaker seizure prediction. A questionnaire was distributed to caretakers of patients with epilepsy. The patients were 0-21years old and experienced ≥1 seizure within the past year. We excluded patients with non-epileptic seizures or daily seizures. One hundred and fifty of 240 questionnaires met criteria. Of these, 32 (21.6%) caretakers indicated a positive report of seizure prediction. Age of seizure onset was earlier in the positive predictive group (3.3±3.3years) than in the non-predictor group (5.3±4.8years) (p=0.01). The most common pre-ictal symptoms reported were being tired, hazy look, and sleepiness. A total of 76.6% of caretakers reported at least one seizure precipitant. The prevalence of positive caretaker seizure prediction in this study is similar to that of seizure self-prediction in adult studies. These findings will be used to design prospective online or electronic diary studies to further investigate the caretaker's, as well as children's, perspectives on seizure prediction. We anticipate that this investigation may lead to novel treatments during times of high seizure risk.

Increased hair cortisol and antecedent somatic complaints in children with a first epileptic seizure

OBJECTIVE

Stress is the most frequent seizure-precipitating factor reported by patients with epilepsy, while stressful life events may increase seizure susceptibility in humans. In this study, we investigated the relations between both biological and behavioral measures of stress in children with a first epileptic seizure (hereafter called seizure). We hypothesized that hair cortisol, a biomarker of chronic stress reflecting approximately 3months of preceding exposure, might be increased in children with a first seizure. We also employed standardized questionnaires to examine presence of stress-related behavioral markers.

METHODS

This was a cross-sectional clinical study investigating stress-related parameters in children with a first seizure (First Epileptic Seizure Group (FESG), n=22) in comparison to healthy children without seizures (Control Group, n=29). Within 24h after a first seizure, hair samples were collected from children for the determination of cortisol. In parallel, perceived stress and anxiety and depressive symptoms were examined with appropriate self- and parent-completed questionnaires, and history of stressful life events during the past year was recorded. Emotional and behavioral problems were also assessed by parent-reported validated and widely-used questionnaires.

RESULTS

Higher hair cortisol measurements were observed in the FESG than control children (7.5 versus 5.0pg/mg respectively, p=0.001). The former were more likely to complain of somatic problems than the latter (59.8 vs. 55.4 according to DSM-oriented Scale, p=0.021); however, there were no differences in perceived stress and anxiety or depressive symptoms between the two groups. Using ROC analysis of hair cortisol measurements for predicting disease status, the maximum sensitivity and specificity were observed for a cut-off point of 5.25pg/mg.

SIGNIFICANCE

Increased hair cortisol indicates chronic hyperactivity of the hypothalamic-pituitary-adrenal (HPA) axis prior to the first seizure. This might have contributed to the epileptogenesis process and may help explain the higher incidence of antecedent somatic complaints in the first seizure group.

Seizure occurrence and the circadian rhythm of cortisol: a systematic review

PURPOSE

Stress is the seizure precipitant most often reported by patients with epilepsy or their caregivers. The relation between stress and seizures is presumably mediated by stress hormones such as cortisol, affecting neuronal excitability. Endogenous cortisol is released in a circadian pattern. To gain insight into the relation between the circadian rhythm of cortisol and seizure occurrence, we systematically reviewed studies on the diurnal distribution of epileptic seizures in children and adults and linked the results to the circadian rhythm of cortisol.

METHODS

A structured literature search was conducted to identify relevant articles, combining the terms 'epilepsy' and 'circadian seizure distribution', plus synonyms. Articles were screened using predefined selection criteria. Data on 24-hour seizure occurrence were extracted, combined, and related to a standard circadian rhythm of cortisol.

RESULTS

Fifteen relevant articles were identified of which twelve could be used for data aggregation. Overall, seizure occurrence showed a sharp rise in the early morning, followed by a gradual decline, similar to cortisol rhythmicity. The occurrence of generalized seizures and focal seizures originating from the parietal lobe in particular followed the circadian rhythm of cortisol.

CONCLUSIONS

The diurnal occurrence of epileptic seizures shows similarities to the circadian rhythm of cortisol. These results support the hypothesis that circadian fluctuations in stress hormone level influence the occurrence of epileptic seizures.

Seizure precipitants in Dravet syndrome: What events and activities are specifically provocative compared with other epilepsies?

OBJECTIVES

This study aimed to describe seizure precipitants in Dravet syndrome (DS) compared with other epilepsies.

METHODS

Seizure precipitants as reported in a Dutch cohort of patients with DS with pathogenic SCN1A mutations (n=71) were compared with those of a cohort with childhood epilepsy (n=149) and of a community-based cohort with epilepsy (n=248); for all three Dutch cohorts, the same type of questionnaire was used. Seizure precipitants were categorized as 'fever', 'visual stimuli', 'sleep deprivation', 'stress, including physical exercise', 'auditory stimuli', and 'other'.

RESULTS

For 70 (99%) of 71 patients with DS, at least one seizure precipitant was recalled by parents. Seizure precipitants that were reported in more than half of the cohort with DS were as follows: having a fever (97%), having a cold (68%), taking a bath (61%), having acute moments of stress (58%), and engaging in physical exercise (56%). Seizure precipitants freely recalled by parents were often related to ambient warmth or cold-warmth shifts (41%) and to various visual stimuli (18%). Patients with DS had more positive seizure precipitant categories (median 4) compared with the cohort with childhood epilepsy (median 2) and the community-based cohort with epilepsy (median 0) (p<0.001) and showed the highest percentage in each category (all p<0.001). Within the category 'stress, including physical exercise', physical exercise was more often reported to provoke seizures in stress-sensitive patients in the cohort with DS than in the cohort with childhood epilepsy (78% vs. 35%, p<0.001). In the cohort with childhood epilepsy, physical exercise was more often reported in fever-sensitive children than in other children (25% vs. 12%, p=0.042).

CONCLUSIONS

Our study shows a high prevalence of a range of seizure precipitants in DS. Our results underscore elevated body temperature as an important seizure precipitant, whether caused by fever, warm bath, ambient warmth, or physical exercise. Knowledge of these seizure precipitants may improve preventive strategies in the otherwise difficult treatment of DS.

Hyper-excitability and epilepsy generated by chronic early-life stress

Epilepsy is more prevalent in populations with high measures of stress, but the neurobiological mechanisms are unclear. Stress is a common precipitant of seizures in individuals with epilepsy, and may provoke seizures by several mechanisms including changes in neurotransmitter and hormone levels within the brain. Importantly, stress during sensitive periods early in life contributes to ‘brain programming’, influencing neuronal function and brain networks. However, it is unclear if early-life stress influences limbic excitability and promotes epilepsy. Here we used an established, naturalistic model of chronic early-life stress (CES), and employed chronic cortical and limbic video-EEGs combined with molecular and cellular techniques to probe the contributions of stress to age-specific epilepsies and network hyperexcitability and identify the underlying mechanisms.

In control male rats, EEGs obtained throughout development were normal and no seizures were observed. EEGs demonstrated epileptic spikes and spike series in the majority of rats experiencing CES, and 57% of CES rats developed seizures: Behavioral events resembling the human age-specific epilepsy infantile spasms occurred in 11/23 (48%), accompanied by EEG spikes and/or electrodecrements, and two additional rats (9%) developed limbic seizures that involved the amygdala. Probing for stress-dependent, endogenous convulsant molecules within amygdala, we examined the expression of the pro-convulsant neuropeptide corticotropin-releasing hormone (CRH), and found a significant increase of amygdalar--but not cortical--CRH expression in adolescent CES rats.

In conclusion, CES of limited duration has long-lasting effects on brain excitability and may promote age-specific seizures and epilepsy. Whereas the mechanisms involved require further study, these findings provide important insights into environmental contributions to early-life seizures.

Early life stress in epilepsy: a seizure precipitant and risk factor for epileptogenesis

Stress can influence epilepsy in multiple ways. A relation between stress and seizures is often experienced by patients with epilepsy. Numerous questionnaire and diary studies have shown that stress is the most often reported seizure-precipitating factor in epilepsy. Acute stress can provoke epileptic seizures, and chronic stress increases seizure frequency. In addition to its effects on seizure susceptibility in patients with epilepsy, stress might also increase the risk of epilepsy development, especially when the stressors are severe, prolonged, or experienced early in life. Although the latter has not been fully resolved in humans, various preclinical epilepsy models have shown increased seizure susceptibility in naïve rodents after prenatal and early postnatal stress exposure. In the current review, we first provide an overview of the effects of stress on the brain. Thereafter, we discuss human as well as preclinical studies evaluating the relation between stress, epileptic seizures, and epileptogenesis, focusing on the epileptogenic effects of early life stress. Increased knowledge on the interaction between early life stress, seizures, and epileptogenesis could improve patient care and provide a basis for new treatment strategies for epilepsy.

Childhood-onset primary generalized epilepsy--impacts on children's preferences for participation in out-of-school activities

The purpose of this study was to compare preferences for participation in out-of-school activities between children with childhood-onset primary generalized epilepsy and their healthy peers. Overall, participants were 56 children aged 6-11 years. The study group included 26 children with childhood-onset primary generalized epilepsy. The controls were 30 healthy children. Parents of all participants completed a demographic and health status questionnaire. All children completed the Preference Assessment of Children (PAC) that profiles the out-of-school activities the child wishes to participate in. Scores are calculated for five activity types, namely, recreational, active physical, social, skill-based, and self-improvement and for two domains of formal and informal activities. Children with generalized epilepsy showed a similar preference for participation in out-of-school activities as did their healthy peers. The study group showed a lower preference for participation in social activities but showed a higher preference for participation in self-improvement activities. In both groups, younger children (aged 6-8 years) showed a lower preference for participation in most PAC scales. Older children (aged 9-11 years) showed a higher preference for participation in social activities. Difference between genders was close to being statistically significant in the skill-based activities (F(1,21)=3.84, p=.06), where girls showed a higher preference compared with boys. Intervention policies need to be undertaken in order to encourage children with epilepsy to participate in activities together with their healthy peers, aiming to enhance the well-being of children with primary generalized epilepsy.

Does Saint Nicholas provoke seizures? Hints from Google Trends

PURPOSE

Stress is the most often reported seizure-precipitant in epilepsy. As most evidence for the relation between stress and epilepsy is derived from human self-reports, observational studies including a larger part of the population could provide additional proof. A stressor often reported to increase seizure frequency in children with epilepsy in the Netherlands is the national celebration of Saint Nicholas' eve (December 5) and the weeks before; this is the main period of festivities for children in this country. To study the relation between stress and epilepsy, we analyzed epilepsy information-seeking behavior on the Internet, an indirect measure of seizure frequency, around this national children's celebration.

METHODS

Google Trends was used to extract relative search percentages for 'epilepsy' on Google in the Netherlands, the United States, and the United Kingdom between 2004 and 2013. Relative search percentages during the Saint Nicholas period were compared with baseline.

RESULTS

Epilepsy searches increased by 14% in the Saint Nicholas period compared with baseline (p<0.001). This effect was not found for searches performed in the same period in the United States or the United Kingdom, countries where this holiday is not celebrated.

CONCLUSIONS

The increase in epilepsy information-seeking behavior in the Saint Nicholas period is possibly caused by an increased occurrence of epileptic seizures. This underscores the potential of health information-seeking behavior on the Internet to answer clinically relevant research questions and provides circumstantial evidence for a relation between stress and the occurrence of epileptic seizures.

Early-life stress impacts the developing hippocampus and primes seizure occurrence: cellular, molecular, and epigenetic mechanisms

Early-life stress includes prenatal, postnatal, and adolescence stress. Early-life stress can affect the development of the hypothalamic-pituitary-adrenal (HPA) axis, and cause cellular and molecular changes in the developing hippocampus that can result in neurobehavioral changes later in life. Epidemiological data implicate stress as a cause of seizures in both children and adults. Emerging evidence indicates that both prenatal and postnatal stress can prime the developing brain for seizures and an increase in epileptogenesis. This article reviews the cellular and molecular changes encountered during prenatal and postnatal stress, and assesses the possible link between these changes and increases in seizure occurrence and epileptogenesis in the developing hippocampus. In addititon, the priming effect of prenatal and postnatal stress for seizures and epileptogenesis is discussed. Finally, the roles of epigenetic modifications in hippocampus and HPA axis programming, early-life stress, and epilepsy are discussed.