Psychiatric Comorbidities in Epilepsy: Identification and Treatment

Impact of Post-Traumatic Epilepsy on Mental Health and Multidimensional Outcome and Quality of Life: An NIDILRR TBIMS Study

Traumatic brain injury (TBI) and subsequent post-traumatic epilepsy (PTE) often impair daily activities and mental health (MH), which contribute to long-term TBI-related disability. PTE also affects driving capacity, which impacts functional independence, community participation, and satisfaction with life (SWL). However, studies evaluating the collective impact of PTE on multidimensional outcomes are lacking. Thus, we generated a model to investigate how PTE after moderate-to-severe (ms)TBI affects TBI-associated impairments, limits activities and participation, and influences SWL. Of 5108 participants with msTBI enrolled into the National Institute for Disability, Independent Living, and Rehabilitation Research TBI Model Systems between 2010 and 2018 and with seizure-event data available at year-1 post-TBI, 1214 had complete outcome data and 1003 had complete covariate data used for analysis. We constructed a conceptual framework illustrating hypothesized interrelationships between year-1 PTE, driving status, functional independence measure (FIM), depression and anxiety, as well as year-2 participation, and SWL. We performed univariate and multivariable linear and logistic regressions. A covariate-adjusted structural equation model (SEM), using the lavaan package (R), assessed the conceptual framework's suitability in establishing PTE links with outcomes 1-2 years post-injury. Multiple parameters were evaluated to assess SEM fit. Year-1 PTE was correlated with year-1 FIM motor (standardized coefficient, βstd = -0.112, p = 0.007) and showed a trend level association with year-1 FIM cognition (βstd = -0.070, p = 0.079). Individuals with year-1 PTE were less likely to drive independently at year 1 (βstd = -0.148, p < 0.001). In addition, FIM motor (βstd = 0.323, p < 0.001), FIM cognition (βstd = 0.181, p = 0.012), and anxiety (βstd = -0.135, p = 0.024) influenced driving status. FIM cognition was associated with year-1 depression (βstd = 0.386, p < 0.001) and year-1 anxiety (βstd = 0.396, p < 0.001), whereas year-1 FIM motor (βstd = 0.186, p = 0.003), depression (βstd = -0.322, p = 0.011), and driving status (βstd = 0.233, p < 0.001) directly affected year-2 objective life participation metrics. Moreover, year-1 depression (βstd = -0.382, p = 0.001) and year-2 participation (βstd = 0.160, p < 0.001) had direct effects on year-2 SWL. SWL was influenced indirectly by year-1 variables, including functional impairment, anxiety, and driving status-factors that impacted year-2 participation directly or indirectly, and consequently year-2 SWL, forming a complex relationship with year-1 PTE. A sensitivity analysis SEM showed that the number of MH disorders was associated with participation and SWL (p < 0.001), and this combined MH variable was directly related to driving status (p < 0.02). Developing PTE during year-1 after msTBI affects multiple aspects of life. PTE effects extend to motor and cognitive abilities, driving capabilities, and indirectly, to life participation and overall SWL. The implications underscore the crucial need for effective PTE management strategies during the first year post-TBI to minimize the adverse impact on factors influencing multidimensional year-2 participation and SWL outcomes. Addressing transportation barriers is warranted to enhance the well-being of those with PTE and msTBI, emphasizing a holistic approach. Further research is recommended for SEM validation studies, including testing causal inference pathways that might inform future prevention and treatment trials.

Unravelling the critical role of neuroinflammation in epilepsy-associated neuropsychiatric comorbidities: A review

Epilepsy is a complex neurological disorder characterized not only by seizures but also by significant neuropsychiatric comorbidities, affecting approximately one-third of those diagnosed. This review explores the intricate relationship between epilepsy and its associated psychiatric and cognitive disturbances, with a focus on the role of inflammation. Recent definitions of epilepsy emphasize its multifaceted nature, linking it to neurobiological, psychiatric, cognitive, and social deficits. Inflammation has emerged as a critical factor influencing both seizure activity and neuropsychiatric outcomes in epilepsy patients. This paper critically examines how dysregulated inflammatory pathways disrupt neurotransmitter transmission and contribute to depression, mood disorders, and anxiety prevalent among individuals with epilepsy. It also evaluates current therapeutic approaches and underscores the potential of anti-inflammatory therapies in managing epilepsy and related neuropsychiatric conditions. Additionally, the review highlights the importance of the anti-inflammatory effects of anti-seizure medications, antidepressants, and antipsychotics and their therapeutic implications for mood disorders. Also, the role of ketogenic diet in managing epilepsy and its psychiatric comorbidities is briefly presented. Furthermore, it briefly discusses the role of the gut-brain axis in maintaining neurological health and how its dysregulation is associated with epilepsy. The review concludes that inflammation plays a pivotal role in linking epilepsy with its neuropsychiatric comorbidities, suggesting that targeted anti-inflammatory interventions may offer promising therapeutic strategies. Future research should focus on longitudinal studies comparing outcomes between epileptic patients with and without neuropsychiatric comorbidities, the development of diagnostic tools, and the exploration of novel anti-inflammatory treatments to better manage these complex interactions.

Development and validation of the Japanese version of the Public Attitudes Toward Epilepsy (PATE-J) Scale

Aim

This study aimed to develop and validate a Japanese version of the Public Attitudes Toward Epilepsy (PATE-J) Scale to measure attitudes towards epilepsy among the general Japanese population.

Methods

The study employed a cross-sectional design using an online survey of 537 participants from the general public in Japan, with follow-up surveys at 2 weeks and 3 months. The PATE Scale was translated following standard guidelines and validated by conducting confirmatory factor analysis (CFA) on the complete data set to assess the original two-factor structure of the PATE Scale. Internal consistency assessment, and convergent validity testing with the Modified Epilepsy Stigma Scale (M-ESS), Perceived Devaluation Discrimination Scale (PDDS), and Epilepsy Knowledge Scale (EKS) were carried out.

Results

CFA confirmed the two-factor structure of the PATE-J, comprising "Personal Domain" and "General Domain." The model showed acceptable fit indices (χ²(76) = 607.974, comparative fit index = 0.849, Tucker-Lewis index = 0.820, root-mean-square error of approximation = 0.114, standardized root-mean-square residual = 0.078) and high reliability (Cronbach's α = 0.87 for Personal Domain and 0.75 for General Domain). Strong correlations with the M-ESS (r = 0.713, p < 0.001), and weaker correlations with the PDDS, along with a negative correlation with the EKS (r = -0.306, p < 0.001), highlighted the PATE-J's distinctiveness. No significant associations were found between demographic factors and PATE-J scores.

Conclusion

The PATE-J demonstrates strong psychometric properties and cultural relevance for measuring public attitudes toward epilepsy in Japan. Its validated two-factor structure supports cross-cultural comparisons and provides a reliable tool for assessing public attitudes, informing interventions, and guiding education campaigns.

Age-Dependent Phenomena of 6-Hz Corneal Kindling Model in Mice

Although numerous studies have acknowledged disparities in epilepsy-related disease processes between young and aged animals, little is known about how epilepsy changes from young adulthood to middle age. This study investigates the impact of aging on 6-Hz corneal kindling in young-adult mice and middle-aged mice. We found that the kindling acquisition of the 6-Hz corneal kindling model was delayed in middle-aged mice when compared to young-adult mice. While the seizure stage and incidence of generalized seizures (GS) were similar between the two age groups, the duration of GS in the kindled middle-aged mice was shorter than that in the kindled young-adult mice. Besides, all kindled mice, regardless of age, were resistant to phenytoin sodium (PHT), valproate sodium (VPA), and lamotrigine (LGT), whereas middle-aged mice exhibited higher levetiracetam (LEV) resistance compared to young-adult mice. Both age groups of kindled mice displayed hyperactivity and impaired memory, which are common behavioral characteristics associated with epilepsy. Furthermore, middle-aged mice displayed more pronounced astrogliosis in the hippocampus. Additionally, the expression of Brain-Derived Neurotrophic Factor (BDNF) was lower in middle-aged mice than in young-adult mice prior to kindling. These data demonstrate that both the acquisition and expression of 6-Hz corneal kindling are attenuated in middle-aged mice, while hippocampal astrogliosis and pharmacological resistance are more pronounced in this age group. These results underscore the importance of considering age-related factors when utilizing the 6-Hz corneal kindling model in mice of varying age groups.

Peri-ictal psychiatric manifestations in people with epilepsy: An umbrella review

OBJECTIVE

We aimed to conduct an umbrella review to summarize the existing evidence regarding the prevalence of peri-ictal psychiatric manifestations (PM) in people with epilepsy (PWE) including pre-ictal, ictal, and postictal stages.

METHODS

Databases were searched up to June 2023 for systematic reviews (SR) of observational studies that included patients with epilepsy peri-ictal PM. Data selection, data extraction, and risk of bias assessment (with the AMSTAR-2 instrument) were performed by two independent reviewers. We performed a narrative synthesis using previous guidelines. We used a self-developed decision table according to the GRADE system adapted for narrative outcomes if the certainty of outcomes was not determined by systematic review authors.

RESULTS

Four SRs were included comprising 66 primary studies (n = 10 217). Three SRs evaluated one period (pre-ictal, ictal, and postictal), and one did not determine it. During the pre-ictal period, the more prevalent symptom was confusion, although with a low certainty (due to the heterogeneity and serious risk of bias). One systematic review that only included case reports evaluated the ictal period, finding mood/anxiety disorders, psychosis, and personality changes. The postictal period included the most PM (anxiety: 45.0% and depressive symptoms: 43.0%), with very low certainty, due to risk of bias, potential publication bias, heterogeneity, and failure to report the confidence intervals.

SIGNIFICANCE

With very low certainty, epileptic periods are characterized by a wide spectrum of PM, being postictal symptoms the most prevalent, predominantly anxiety, and depressive symptoms. Further understanding of these PM of epilepsy could improve the attention of the people with epilepsy.

PLAIN LANGUAGE SUMMARY

In this review of reviews, we summarize the frequency in which psychiatric manifestations occur in relation to an epileptic seizure. A total of 10 217 patients were reported in the reviews. The most common manifestations included symptoms of anxiety and depression, as well as changes in the normal behavior of the patient. These manifestations occurred most frequently right after the seizure finished.

Abnormal patterns of sleep and waking behaviors are accompanied by neocortical oscillation disturbances in an Ank3 mouse model of epilepsy-bipolar disorder comorbidity

ANK3 is a leading bipolar disorder (BD) candidate gene in humans and provides a unique opportunity for studying epilepsy-BD comorbidity. Previous studies showed that deletion of Ank3-1b, a BD-associated variant of Ank3 in mice leads to increased firing threshold and diminished action potential dynamic range of parvalbumin (PV) interneurons and absence epilepsy, thus providing a biological mechanism linking epilepsy and BD. To explore the behavioral overlap of these disorders, we characterized behavioral patterns of Ank3-1b KO mice during overnight home-cage activity and examined network activity during these behaviors using paired video and EEG recordings. Since PV interneurons contribute to the generation of high-frequency gamma oscillations, we anticipated changes in the power of neocortical EEG signals in the gamma frequency range (> 25 Hz) during behavioral states related to human BD symptoms, including abnormal sleep, hyperactivity, and repetitive behaviors. Ank3-1b KO mice exhibited an overall increase in slow gamma (~25-45 Hz) power compared to controls, and slow gamma power correlated with seizure phenotype severity across behaviors. During sleep, increased slow gamma power correlated with decreased time spent in the rapid eye movement (REM) stage of sleep. Seizures were more common during REM sleep compared to non-REM (NREM) sleep. We also found that Ank3-1b KO mice were hyperactive and exhibited a repetitive behavior phenotype that co-occurred with increased slow gamma power. Our results identify a novel EEG biomarker associating Ank3 genetic variation with BD and epilepsy and suggest modulation of gamma oscillations as a potential therapeutic target.

Psychiatric outcomes after temporal lobe surgery in patients with temporal lobe epilepsy and comorbid psychiatric illness: A systematic review and meta-analysis

BACKGROUND

The currently available evidence is unclear in regard to psychiatric outcomes of temporal lobe epilepsy (TLE) in patients with comorbid psychiatric disorders (PD).

AIM

To identify and synthesize psychiatric outcomes in patients with TLE and comorbid psychiatric illnesses before and after TLE surgery.

METHODS

Studies were included if participants were adults and/or children with temporal epilepsy and comorbid psychiatric illness. Surgical interventions included focal resection (e.g., lobectomy, selective amygdalohippocampectomy) or stereotactic laser ablation. Included studies reported on pre- and post- surgery data of comorbid psychiatric illness (e.g., mood and anxiety disorders, depression, psychosis, adjustment disorders, non-epileptic seizures, and personality disorders).

RESULTS

Ten studies were included in the review. The proportion of patients achieving PD resolution or improvements after surgery varied widely between studies, ranging from 15 % to 57 % at the reported follow-up time. Three studies reported on PD symptom worsening after surgery, with considerable variations of patient proportions across studies. Meta-analysis suggests that 43 % of patients demonstrated improvement and 33 % of patients showed a worsening in psychiatric scores across all studies. Preliminary data from three studies suggest that seizure control may be associated with favourable psychiatric outcomes.

CONCLUSION

A considerable proportion of reported TLE patients with comorbid psychiatric illnesses have improvement in their psychiatric symptoms after temporal lobe epilepsy surgery. There is scarcity of detailed outcome reporting including symptom scores, and to date, predictive factors for favourable vs unfavourable outcomes in this patient population are not clear. Further research on the topic is warranted.

Anxiety and hippocampal neuronal activity: Relationship and potential mechanisms

The hippocampus has been implicated in modulating anxiety. It interacts with a variety of brain regions, both cortical and subcortical areas regulating emotion and stress responses, including prefrontal cortex, amygdala, hypothalamus, and the nucleus accumbens, to adjust anxiety levels in response to a variety of stressful conditions. Growing evidence indicates that anxiety is associated with increased neuronal excitability in the hippocampus, and alterations in local regulation of hippocampal excitability have been suggested to underlie behavioral disruptions characteristic of certain anxiety disorders. Furthermore, studies have shown that some anxiolytics can treat anxiety by altering the excitability and plasticity of hippocampal neurons. Hence, identifying cellular and molecular mechanisms and neural circuits that regulate hippocampal excitability in anxiety may be beneficial for developing targeted interventions for treatment of anxiety disorders particularly for the treatment-resistant cases. We first briefly review a role of the hippocampus in fear. We then review the evidence indicating a relationship between the hippocampal activity and fear/anxiety and discuss some possible mechanisms underlying stress-induced hippocampal excitability and anxiety-related behavior.

Assessment of Anxiety in Patients With Epilepsy: A Literature Review

Objective

Approximately 20% of people with epilepsy (PWE) suffer from anxiety. These fears are quite diverse and may manifest periictally or interictally, be part of the seizure's semiology, or an expression of reactive psychological distress from seizures themselves. Our review addresses the question of what screening tools are used in clinical care and epileptological research to capture the complexity of epilepsy-specific anxieties.

Method

On 2021/11/11, we entered a search string in PubMed that covered our research interest as completely as possible. We also screened the bibliographies of our findings and followed PubMed's recommendations. From the assessments we found in the included studies, we extracted domains that represent the range of manifestations of anxiety, in order to compare the tools and to discuss to what extent they are suitable for assessing epilepsy-specific anxieties.

Results

We screened 1,621 abstracts. In total, we identified 24 different anxiety assessments. In addition to the psychiatric assessments in use, we found 7 tools that were designed to assess epilepsy-specific anxieties. The latter focus on different aspects of epilepsy-specific anxieties. In some cases, the conceptual frameworks are not sufficiently transparent or divergent.

Conclusion

Because a diagnosis of epilepsy can result in, or seizures may appear as, anxiety, it is important to better understand this psychological burden and address it therapeutically, if necessary. There is a need for screening tools that integrate specific points of a variety of assessments, so as to cover the broad range of epilepsy-specific fears. None of the assessments we found meets this integrative perspective. At the same time, the appropriate design of such a required tool presupposes a conceptual framework of what should be considered as epilepsy-specific anxiety.

Evaluation of suicide probability in children and adolescents with epilepsy

BACKGROUND

We aimed to examine suicide probability, factors affecting suicide, and personality traits of children and adolescents diagnosed with epilepsy, and to compare their results with those of children without epilepsy.

METHODS

Fifty-six children diagnosed with epilepsy and 56 control children, aged 11-16 years, were evaluated by using the Diagnostic and Statistical Manual of Mental Disorders diagnostic criteria, the Kiddie Schedule for Affective Disorders and Schizophrenia Present and Lifetime Version, the Child Depression Inventory, the Suicide Probability Scale (SPS), and the Personality Inventory for DSM-5 - Brief Form - Children (PID-5-BF) scales. Factors predicting suicide risk in children with epilepsy were analyzed.

RESULTS

The mean age, SPS total score, and hopelessness subscale score, PID-5-BF total score as well as disinhibition and psychoticism subscale scores of the epilepsy group were significantly higher than those of the control group (P < 0.05). There was no significant difference between the groups in terms of the Child Depression Inventory, and other subscales of the Suicide Probability Scales and PID-5-BF scales. The SPS total score was higher in patients with comorbid psychiatric diseases, those using psychiatric drugs, and girls (P < 0.05). An ANCOVA analysis indicated that the most important factor that predicted the probability of suicide and its subscale scores was the level of depression, and the presence of epilepsy was not predictive.

CONCLUSIONS

We found a high probability of suicide and personality pathology in children with epilepsy but the main predictor of suicide probability was the level of depression, not the presence of epilepsy.

Multipronged Attack of Stem Cell Therapy in Treating the Neurological and Neuropsychiatric Symptoms of Epilepsy

Epilepsy stands as a life-threatening disease that is characterized by unprovoked seizures. However, an important characteristic of epilepsy that needs to be examined is the neuropsychiatric aspect. Epileptic patients endure aggression, depression, and other psychiatric illnesses. Therapies for epilepsy can be divided into two categories: antiepileptic medications and surgical resection. Antiepileptic drugs are used to attenuate heightened neuronal firing and to lessen seizure frequency. Alternatively, surgery can also be conducted to physically cut out the area of the brain that is assumed to be the root cause for the anomalous firing that triggers seizures. While both treatments serve as viable approaches that aim to regulate seizures and ameliorate the neurological detriments spurred by epilepsy, they do not serve to directly counteract epilepsy's neuropsychiatric traits. To address this concern, a potential new treatment involves the use of stem cells. Stem cell therapy has been employed in experimental models of neurological maladies, such as Parkinson's disease, and neuropsychiatric illnesses like depression. Cell-based treatments for epilepsy utilizing stem cells such as neural stem cells (NSCs), mesenchymal stem cells (MSCs), and interneuron grafts have been explored in preclinical and clinical settings, highlighting both the acute and chronic stages of epilepsy. However, it is difficult to create an animal model to capitalize on all the components of epilepsy due to the challenges in delineating the neuropsychiatric aspect. Therefore, further preclinical investigation into the safety and efficacy of stem cell therapy in addressing both the neurological and the neuropsychiatric components of epilepsy is warranted in order to optimize cell dosage, delivery, and timing of cell transplantation.

Chronic Valproic Acid Administration Increases Plasma, Liver, and Brain Ammonia Concentration and Suppresses Glutamine Synthetase Activity

Asymptomatic valproic acid (VPA)-induced hyperammonemia in the absence of liver impairment is fairly common. However, the underlying mechanisms through which VPA causes elevation in plasma ammonia (NH4) remains under investigation. Male Sprague Dawley rats (n = 72) were randomly allocated to receive VPA 400 mg/kg, 200 mg/kg, or vehicle IP daily for either 8, 14, or 28 consecutive days. The behavioral effects of VPA were assessed. Plasma, liver, and prefrontal cortex (PFC), striatum (Str), and cerebellum (Cere) were collected 1 h post last injection and assayed for NH4 concentration and glutamine synthetase (GS) enzyme activity. Chronic VPA treatment caused attenuation of measured behavioral reflexes (p < 0.0001) and increase in plasma NH4 concentration (p < 0.0001). The liver and brain also showed significant increase in tissue NH4 concentrations (p < 0.0001 each) associated with significant reduction in GS activity (p < 0.0001 and p = 0.0003, respectively). Higher tissue NH4 concentrations correlated with reduced GS activity in the liver (r = -0.447, p = 0.0007) but not in the brain (r = -0.058, p = 0.4). Within the brain, even though NH4 concentrations increased in the PFC (p = 0.001), Str (p < 0.0001), and Cere (p = 0.01), GS activity was reduced only in the PFC (p < 0.001) and not in Str (p = 0.2) or Cere (p = 0.1). These results suggest that VPA-induced elevation in plasma NH4 concentration could be related, at least in part, to the suppression of GS activity in liver and brain tissues. However, even though GS is the primary mechanism in brain NH4 clearance, the suppression of brain GS does not seem to be the main factor in explaining the elevation in brain NH4 concentration. Further research is urgently needed to investigate brain NH4 dynamics under chronic VPA treatment and whether VPA clinical efficacy in treating seizure disorders and bipolar mania is impacted by its effect on GS activity or other NH4 metabolizing enzymes.

Psychiatric disorders as predictors of epilepsy surgery outcome

OBJECTIVES

Our aim was to determine if a history of a mental disorder predicts a worst neurological outcome for patients undergoing epilepsy surgery.

METHODS

We conducted an ambispective observational study including people with refractory epilepsy who underwent resective surgery. Demographic, psychiatric, and neurological data were collected, before and one year after surgery. Presurgical interviews included a psychiatric evaluation and the determination of prevalent and lifetime psychiatric diagnosis. The one-year postsurgical outcome was classified according to the Engel Outcome Scale. Predictors of postsurgical Engel class were determined using an ordered logistic regression model.

RESULTS

A lifetime history of any mental disorder was a significant predictor of a higher Engel Class (p = 0.017).

CONCLUSION

This study shows that psychiatric lifetime diagnoses are associated with worse surgical outcome and highlighted the importance of the inclusion of these diagnoses in the evaluation of the potential success of the surgery.

Hydrogen Alleviates Necroptosis and Cognitive Deficits in Lithium-Pilocarpine Model of Status Epilepticus

Status epilepticus without prompt seizure control always leads to neuronal death and long-term cognitive deficits, but effective intervention is still absent. Here, we found that hydrogen could alleviate the hippocampus-dependent spatial learning and memory deficit in lithium-pilocarpine model of status epilepticus in rats, as evidenced by the results in Morris water maze test. Hydrogen treatment downregulated the expression of necroptosis-related proteins, such as MLKL, phosphorylated-MLKL, and RIPK3 in hippocampus, and further protected neurons and astrocytes from necroptosis which was here first verified to occur in status epilepticus. Hydrogen also protected cells from apoptosis, which was indicated by the decreased cleaved-Caspase 3 expression. Meanwhile, Iba1+ microglial activation by status epilepticus was reduced by hydrogen treatment. These findings confirm the utility of hydrogen treatment in averting cell death including necroptosis and alleviating cognitive deficits caused by status epilepticus. Therefore, hydrogen may provide a potential and powerful clinical treatment for status epilepticus-related cognitive deficits.

Impairments in cognitive functions and emotional and social behaviors in a rat lithium-pilocarpine model of temporal lobe epilepsy

The aim of this study was to evaluate in detail behavioral patterns and comorbid disturbances in rats using the lithium-pilocarpine model. A comprehensive set of behavioral tests was used to investigate behavioral patterns, including the open field test, Morris water maze, Y-maze, fear conditioning, the elevated plus maze, the forced swimming test, and the resident-intruder paradigm. Motor and explorative activity, learning and memory, anxiety and depressive-like behavior, aggression, and communication were evaluated 8-15 d after pilocarpine-induced status epilepticus (SE) (latent phase of the model) and 41-53 d (chronic phase) after pilocarpine-induced SE. Increased motor activity and impaired memory function were the most noticeable behavioral modifications in the epileptic rats. Both the movement speed and distance traveled increased in the open field test in both the latent and chronic phases. Significant impairments were detected in short-and long-term spatial memory in the Morris water maze during the latent phase. Besides the alterations in spatial memory, behaviors indicative of short- and long-term fear-associated memory disturbances were observed in the fear conditioning test during the chronic phase of the model. In the resident-intruder paradigm, epileptic rats exhibited disturbed communicative behavior, with impaired social behaviors. In contrast, emotional disturbances were less prominent, with the rats exhibiting decreased anxiety. There were no changes in depressive-like behavior. The data suggest that the lithium-pilocarpine model of TLE in rodents is more useful for studies of comorbid disturbances in memory, hyperactivity, and social behavior than for research on psychoemotional impairments, such as anxiety and depression.

Prevalence of psychiatric disorders in Thai patients with epilepsy

BACKGROUND

Many studies have shown that the prevalence of psychiatric disorders in patients with epilepsy (PWE) appears higher than that in general population. However, most epidemiological studies regarding psychiatric comorbidities among PWE were conducted in Western countries. This work aimed to determine the prevalence of psychiatric disorders in Thai PWE, including potential variables that could be associated with psychiatric disorders.

METHODS

A cross-sectional study was conducted at Ramathibodi Hospital. A total of 170 patients (aged 18 years or older) diagnosed as having epilepsy by a neurologist were recruited at the outpatient neurology clinic. Demographic and clinical characteristics were collected. Participants were evaluated for any psychiatric disorders according to the Diagnostic and Statistical Manual of Mental Disorders, 4th edition, using a structured diagnostic interview. The prevalence of psychiatric disorders was determined. The associations between potential variables and the presence of psychiatric disorders in PWE were analyzed using chi-square or Fisher's exact tests, t-test, and logistic regression.

RESULTS

Among 170 patients, 43 (25.3%) fulfilled diagnostic criteria for one or more psychiatric disorders. The prevalence of depressive disorders was shown to be highest at 17.1%, followed by psychotic disorders (8.2%), bipolar disorder (7.1%), anxiety disorders (5.3%), and obsessive-compulsive disorder (OCD) (2.9%). Electroencephalogram (EEG) abnormalities in the temporal lobe was found to be a significant predictor of having psychiatric disorders in PWE (adjusted odds ratio (OR): 4.01, 95% confidence interval (CI): 1.47-10.92, P-value = 0.007).

CONCLUSIONS

The prevalence of psychiatric disorders among Thai PWE was higher than that in general population. Screening for psychiatric disorders in PWE is recommended, especially among those who have EEG abnormalities in the temporal lobe.

Immunity and inflammation in status epilepticus and its sequelae: possibilities for therapeutic application

Status epilepticus (SE) is a life-threatening neurological emergency often refractory to available treatment options. It is a very heterogeneous condition in terms of clinical presentation and causes, which besides genetic, vascular and other structural causes also include CNS or severe systemic infections, sudden withdrawal from benzodiazepines or anticonvulsants and rare autoimmune etiologies. Treatment of SE is essentially based on expert opinions and antiepileptic drug treatment per se seems to have no major impact on prognosis. There is, therefore, urgent need of novel therapies that rely upon a better understanding of the basic mechanisms underlying this clinical condition. Accumulating evidence in animal models highlights that inflammation ensuing in the brain during SE may play a determinant role in ongoing seizures and their long-term detrimental consequences, independent of an infection or auto-immune cause; this evidence encourages reconsideration of the treatment flow in SE patients.

Hippocampal Pathophysiology: Commonality Shared by Temporal Lobe Epilepsy and Psychiatric Disorders

Accumulating evidence points to the association of epilepsy, particularly, temporal lobe epilepsy (TLE), with psychiatric disorders, such as schizophrenia. Among these illnesses, the hippocampus is considered the regional focal point of the brain, playing an important role in cognition, psychosis, and seizure activity and potentially suggesting common etiologies and pathophysiology of TLE and schizophrenia. In the present review, we overview abnormal network connectivity between the dentate gyrus (DG) and the Cornus Ammonis area 3 (CA3) subregions of the hippocampus relative to the induction of epilepsy and schizophrenia. In light of our recent finding on the misguidance of hippocampal mossy fiber projection in the rodent model of schizophrenia, we discuss whether ectopic mossy fiber projection is a commonality in order to evoke TLE as well as symptoms related to schizophrenia.

Harnessing neural stem cells for treating psychiatric symptoms associated with fetal alcohol spectrum disorder and epilepsy

Brain insults with progressive neurodegeneration are inherent in pathological symptoms that represent many psychiatric illnesses. Neural network disruptions characterized by impaired neurogenesis have been recognized to precede, accompany, and possibly even exacerbate the evolution and progression of symptoms of psychiatric disorders. Here, we focus on the neurodegeneration and the resulting psychiatric symptoms observed in fetal alcohol spectrum disorder and epilepsy, in an effort to show that these two diseases are candidate targets for stem cell therapy. In particular, we provide preclinical evidence in the transplantation of neural stem cells (NSCs) in both conditions, highlighting the potential of this cell-based treatment for correcting the psychiatric symptoms that plague these two disorders. Additionally, we discuss the challenges of NSC transplantation and offer insights into the mechanisms that may mediate the therapeutic benefits and can be exploited to overcome the hurdles of translating this therapy from the laboratory to the clinic. Our ultimate goal is to advance stem cell therapy for the treatment of psychiatric disorders.

Ankyrin-G isoform imbalance and interneuronopathy link epilepsy and bipolar disorder

ANK3, encoding the adaptor protein Ankyrin-G (AnkG), has been implicated in bipolar disorder by genome-wide association studies. ANK3 has multiple alternative first exons, and a bipolar disorder-associated ANK3 variant has been shown to reduce the expression of exon 1b. Here we identify mechanisms through which reduced ANK3 exon 1b isoform expression disrupts neuronal excitation-inhibition balance. We find that parvalbumin (PV) interneurons and principal cells differentially express ANK3 first exon subtypes. PV interneurons express only isoforms containing exon 1b, whereas excitatory principal cells express exon 1e alone or both 1e and 1b. In transgenic mice deficient for exon 1b, PV interneurons lack voltage-gated sodium channels at their axonal initial segments and have increased firing thresholds and diminished action potential dynamic range. These mice exhibit an Ank3 gene dosage-dependent phenotype including behavior changes modeling bipolar disorder, epilepsy and sudden death. Thus ANK3's important association with human bipolar susceptibility may arise from imbalance between AnkG function in interneurons and principal cells and resultant excessive circuit sensitivity and output. AnkG isoform imbalance is a novel molecular endophenotype and potential therapeutic target.

Psychiatric symptoms after temporal epilepsy surgery. A one-year follow-up study

Psychiatric symptoms must be considered in patients with refractory temporal lobe epilepsy after epilepsy surgery. The main objectives of our study were to describe clinical and socio-demographical characteristics of a cohort of patients with pharmacoresistant temporal lobe epilepsy who underwent temporal lobe epilepsy surgery, and moreover, to evaluate possible risk factors for developing psychiatric symptoms. In order to achieve those goals, we conducted a prospective evaluation of psychopathology throughout the first year after surgery in a clinical sample of 72 patients, by means of three clinical rated measures; the Hamilton Anxiety Rating Scale (HARS), the Hamilton Depression Rating Scale (HDRS), and the Brief Psychiatric Rating Scale (BPRS). The psychopathological evaluations were performed by an experienced psychiatrist. A presurgical evaluation was done by a multidisciplinary team (that includes neurologist, psychiatrist, neurosurgeon, neurophysiologist, radiologists, and nuclear medicine specialist) in all patients. The decision to proceed to surgery was taken after a surgical meeting of all members of the Multidisciplinary Epilepsy Unit team. The psychiatrist conducted two postoperative assessments at 6months and 12months after surgery. The main finding was that past history of mental illness (patients who were receiving psychiatric treatment prior to the baseline evaluation) was a risk factor for anxiety, depression, and psychosis after temporal lobe epilepsy surgery.

To what extent does depression influence quality of life of people with pharmacoresistant epilepsy in Argentina?

INTRODUCTION

Depression is the most frequent psychiatric co-morbidity in patients with epilepsy. Lifetime prevalence of depression is reported more frequently in temporal lobe epilepsy and is estimated at 35%. This co-morbidity appears to be related with various mechanisms. The aim of this study was to determine the quality of life (QoL) of patients with pharmacoresistant epilepsy with and without co-morbid depression in an Argentinean population.

METHODS

Patients admitted to the video-EEG monitoring unit during the period 2010-2013 went through a standardized psychiatric assessment using SCID-I (Structured Clinical Interview for Axis I diagnoses of DSM-IV), BDI II (Beck Depression Inventory) GAF (Global assessment of functioning), and Q LES Q-SF (for quality of life). Patients were divided in two groups: with and without depression (according to DSM-IV). Sociodemographic data, BDI II scores, GAF, and quality of life (QoL) were compared between the two groups. Comparisons were made using Student's t-test and Mann-Whitney U test. Frequency distributions were compared by Chi-square test. Spearman correlation coefficients were determined.

RESULTS

Seventy-seven patients with pharmacoresistant epilepsy were eligible for this study, 41 patients were included in the group with depression (mean BDI II 15.93), and 36 in the group without depression (mean BDI II 3.36) (p=0.001). The overall QoL was significantly lower in the group with depression compared to the group without depression (p<0.01). The most affected areas were: physical health (p=0.013), mood (p=0.006), course activities (referring to school as well as to hobbies or classes outside of school) (p=0.003), leisure time activities (p=0.011), social activities (p=0.047), general activities (p=0.042), and medication (p=0.022). Severity of depression according to BDI II had a negative correlation with overall QoL (r - 0.339, p<0.01). No correlations were found between seizure frequency, QoL and BDI II.

CONCLUSION

Patients with pharmacoresistant epilepsy and co-morbid depression reported worst QoL. Depression disrupts daily functioning (leisure, social functioning) and is a negative influence for subjective perception of health and medication. Interdisciplinary treatment should be considered (neurology-psychiatry-psychotherapy).

Epilepsy coexisting with depression

Depression episodes in epilepsy is the most common commorbidity, affecting between 11% and 62% of patients with epilepsy. Although researchers have documented a strong association between epilepsy and psychiatric comorbidities, the nature of this relationship is poorly understood. The manifestation of depression in epilepsy is a complex issue having many interacting neurobiological and psychosocial determinants, including clinical features of epilepsy (seizure frequency, type, foci, or lateralization of foci) and neurochemical or iatrogenic mechanisms. Other risk factors are a family history of psychiatric illness, particularly depression, a lack of control over the seizures and iatrogenic causes (pharmacologic and surgical). In addition, treatment with antiepileptic drugs (AEDs) as well as social coping and adaptation skills have also been recognised as risk factors of depression associated with epilepsy. Epilepsy may foster the development of depression through being exposed to chronic stress. The uncertainty and unpredictability of seizures may instigate sadness, loneliness, despair, low self-esteem, and self-reproach in patients with epilepsy and lead to social isolation, stigmatization, or disability. Often, depression is viewed as a reaction to epilepsy's stigma and the associated poor quality of life. Moreover, patients with epilepsy display a 4-5 higher rate of depression and suicide compared with healthy population.

Contemplating stem cell therapy for epilepsy-induced neuropsychiatric symptoms

Epilepsy is a debilitating disease that impacts millions of people worldwide. While unprovoked seizures characterize its cardinal symptom, an important aspect of epilepsy that remains to be addressed is the neuropsychiatric component. It has been documented for millennia in paintings and literature that those with epilepsy can suffer from bouts of aggression, depression, and other psychiatric ailments. Current treatments for epilepsy include the use of antiepileptic drugs and surgical resection. Antiepileptic drugs reduce the overall firing of the brain to mitigate the rate of seizure occurrence. Surgery aims to remove a portion of the brain that is suspected to be the source of aberrant firing that leads to seizures. Both options treat the seizure-generating neurological aspect of epilepsy, but fail to directly address the neuropsychiatric components. A promising new treatment for epilepsy is the use of stem cells to treat both the biological and psychiatric components. Stem cell therapy has been shown efficacious in treating experimental models of neurological disorders, including Parkinson's disease, and neuropsychiatric diseases, such as depression. Additional research is necessary to see if stem cells can treat both neurological and neuropsychiatric aspects of epilepsy. Currently, there is no animal model that recapitulates all the clinical hallmarks of epilepsy. This could be due to difficulty in characterizing the neuropsychiatric component of the disease. In advancing stem cell therapy for treating epilepsy, experimental testing of the safety and efficacy of allogeneic and autologous transplantation will require the optimization of cell dosage, delivery, and timing of transplantation in a clinically relevant model of epilepsy with both neurological and neuropsychiatric symptoms of the disease as the primary outcome measures.

Psychiatric disorders comorbid with epilepsy in a prison sample

PURPOSE

Epilepsy is an extremely widespread and serious neurological disease. Although comorbidities of psychiatric disorders are prevalent in epilepsy patients, quite often this coexistence could be overlooked. Studies in this area demonstrated that depression, anxiety disorders and schizophrenia are the most common psychiatric disorders accompanying epilepsy. Mental health problems are known to be more common in prisoners compared to general population. The present study aims to demonstrate the psychiatric comorbidities in prisoners diagnosed with epilepsy.

METHOD

In this study, demographic data and the psychiatric comorbidity of 200 patients who were diagnosed with epilepsy by a neurologist at Ankara Penal Institution Campus State Hospital between January 2013 and January 2014 were analyzed retrospectively.

RESULTS

The mean age of study population was 32.6±10.1years. 181 of these patients were male (90.5%). 81 of 200 patients (40.5%) had a comorbid psychiatric disorder. The most common comorbid psychiatric disorders were depression (18.5%), anxiety (11%), and personality disorders (11%), respectively.

CONCLUSION

The most common psychiatric comorbid disorders among prisoners diagnosed with epilepsy were depression and anxiety as general population with epilepsy whereas some disorders, personality disorder, substance dependence and bipolar affective disorders, were found to be more common among prisoners compared to the general population with epilepsy. It is crucial to question psychiatric symptoms and comorbidities while evaluating the patients with epilepsy, especially among prisoners.

Direct Imaging of Hippocampal Epileptiform Calcium Motifs Following Kainic Acid Administration in Freely Behaving Mice

Prolonged exposure to abnormally high calcium concentrations is thought to be a core mechanism underlying hippocampal damage in epileptic patients; however, no prior study has characterized calcium activity during seizures in the live, intact hippocampus. We have directly investigated this possibility by combining whole-brain electroencephalographic (EEG) measurements with microendoscopic calcium imaging of pyramidal cells in the CA1 hippocampal region of freely behaving mice treated with the pro-convulsant kainic acid (KA). We observed that KA administration led to systematic patterns of epileptiform calcium activity: a series of large-scale, intensifying flashes of increased calcium fluorescence concurrent with a cluster of low-amplitude EEG waveforms. This was accompanied by a steady increase in cellular calcium levels (>5 fold increase relative to the baseline), followed by an intense spreading calcium wave characterized by a 218% increase in global mean intensity of calcium fluorescence (n = 8, range [114–349%], p < 10⁻⁴; t-test). The wave had no consistent EEG phenotype and occurred before the onset of motor convulsions. Similar changes in calcium activity were also observed in animals treated with 2 different proconvulsant agents, N-methyl-D-aspartate (NMDA) and pentylenetetrazol (PTZ), suggesting the measured changes in calcium dynamics are a signature of seizure activity rather than a KA-specific pathology. Additionally, despite reducing the behavioral severity of KA-induced seizures, the anticonvulsant drug valproate (VA, 300 mg/kg) did not modify the observed abnormalities in calcium dynamics. These results confirm the presence of pathological calcium activity preceding convulsive motor seizures and support calcium as a candidate signaling molecule in a pathway connecting seizures to subsequent cellular damage. Integrating in vivo calcium imaging with traditional assessment of seizures could potentially increase translatability of pharmacological intervention, leading to novel drug screening paradigms and therapeutics designed to target and abolish abnormal patterns of both electrical and calcium excitation.

Exploring the efficacy of a 5-day course of transcranial direct current stimulation (TDCS) on depression and memory function in patients with well-controlled temporal lobe epilepsy

INTRODUCTION

Depression and memory dysfunction significantly impact the quality of life of patients with epilepsy. Current therapies for these cognitive and psychiatric comorbidities are limited. We explored the efficacy and safety of transcranial direct current stimulation (TDCS) for treating depression and memory dysfunction in patients with temporal lobe epilepsy (TLE).

METHODS

Thirty-seven (37) adults with well-controlled TLE were enrolled in a double-blinded, sham-controlled, randomized, parallel-group study of 5 days of fixed-dose (2 mA, 20 min) TDCS. Subjects were randomized to receive either real or sham TDCS, both delivered over the left dorsolateral prefrontal cortex. Patients received neuropsychological testing and a 20-minute scalp EEG at baseline immediately after the TDCS course and at 2- and 4-week follow-up.

RESULTS

There was improvement in depression scores immediately after real TDCS, but not sham TDCS, as measured by changes in the Beck Depression Inventory (BDI change: -1.68 vs. 1.27, p<0.05) and NDDI-E (-0.83 vs. 0.9091, p=0.05). There was no difference between the groups at the 2- or 4-week follow-up. There was no effect on delayed or working memory performance. Transcranial direct current stimulation was well-tolerated and did not increase seizure frequency or interictal discharge frequency. Transcranial direct current stimulation induced an increase in delta frequency band power over the frontal region and delta, alpha, and theta band power in the occipital region after real stimulation compared to sham stimulation, although the difference did not reach statistical significance.

DISCUSSION

This study provides evidence for the use of TDCS as a safe and well-tolerated nonpharmacologic approach to improving depressive symptoms in patients with well-controlled TLE. However, there were no changes in memory function immediately following or persisting after a stimulation course. Further studies may determine optimal stimulation parameters for maximal mood benefit.

The role of seizure disorders in burn injury and outcome in Sub-Saharan Africa

Patients with epilepsy have higher incidence and severity of burn injury. Few studies describe the association between epilepsy and burns in low-income settings, where epilepsy burden is highest. The authors compared patients with and without seizure disorder in a burn unit in Lilongwe, Malawi. The authors conducted a retrospective study of patients admitted to the Kamuzu Central Hospital burn ward from July 2011 to December 2012. Descriptive analysis of patient characteristics and unadjusted and adjusted analyses of risk factors for mortality were conducted for patients with and without seizure disorder. Prevalence of seizure disorder was 10.7% in the study population. Adults with burns were more likely to have seizure disorder than children. Flame injury was most common in patients with seizure disorder, whereas scalds predominated among patients without seizure disorder. Whereas mortality did not differ between the groups, mean length of stay was longer for patients with seizure disorder, 42.1 days vs 21.6 days. Seizure disorder continues to be a significant risk factor for burn injury in adults in Malawi. Efforts to mitigate epilepsy will likely lead to significant decreases in burns among adults in Sub-Saharan Africa and must be included in an overall burn prevention strategy in our environment.

Patterns and frequency of the treatment of depression in persons with epilepsy

OBJECTIVE

Though depression is common in persons with epilepsy, it often remains undiagnosed and/or untreated. The current study aimed to determine the proportion of persons with epilepsy receiving depression-related treatment and to characterize the type of treatment received.

METHODS

Persons with epilepsy (n=185) from the only epilepsy clinic in a city of 1.2 million people completed questionnaires and the gold-standard Structured Clinical Interview for DSM Disorders (SCID) to assess current and past depression. Treatment for depression (pharmacological and nonpharmacological) was ascertained through patient self-report and chart review.

RESULTS

Of those with current depression (n=27), the majority (70.3%) were not on any depression-related treatment. In persons with current depression, nonpharmacological management was the most common treatment method, followed by treatment with psychotropic medications such as selective serotonin reuptake inhibitors. More individuals with a past history of depression but without a current episode (n=43) were treated (37.2%); it was more common for these individuals to be treated with pharmacological measures. After using an algorithm that adjusts the treated prevalence for those who are successfully treated, the adjusted proportion of depression treatment was 53.1%.

CONCLUSIONS

The proportion of people treated for current depression in this cohort was very low. Future studies should investigate barriers to treatment and how depression treatment can be optimized for those with epilepsy.

Presynaptic mechanisms of neuronal plasticity and their role in epilepsy

Synaptic communication requires constant adjustments of pre- and postsynaptic efficacies. In addition to synaptic long term plasticity, the presynaptic machinery underlies homeostatic regulations which prevent out of range transmitter release. In this minireview we will discuss the relevance of selected presynaptic mechanisms to epilepsy including voltage- and ligand-gated ion channels as well as cannabinoid and adenosine receptor signaling.

Scn8a voltage-gated sodium channel mutation alters seizure and anxiety responses to acute stress

Stress is known to trigger seizures in patients with epilepsy, highlighting the physiological stress response as a possible therapeutic target for epilepsy treatment. Nevertheless, little is currently known about how a genetic predisposition to epilepsy interacts with the stress response to influence seizure outcome. To address this question, we examined the effect of acute stress on seizure outcome in mice with mutations in the voltage-gated sodium channel (VGSC) gene Scn8a. Scn8a mutants display spontaneous spike-wave discharges (SWDs) characteristic of absence epilepsy. We saw that the baseline frequency of SWDs in Scn8a mutants correlates closely with the diurnal activity of the hypothalamic-pituitary-adrenal (HPA) axis, with a peak in seizure activity occurring at around the same time as the peak in corticosterone (1700-1900h). A 20-min acute restraint stress administered in the morning increases the frequency of spontaneous SWDs immediately following the stressor. Seizure frequency then returns to baseline levels within 3h after stressor exposure, but the subsequent evening peak in seizure frequency is delayed and broadened, changes that persist into the next evening and are accompanied by long-lasting changes in HPA axis activity. Scn8a mutants also show increased anxiety-like behavior in mildly stressful situations. A 20-min acute restraint stress can also increase the severity and duration of chemically induced seizures in Scn8a mutants, changes that differ from wild-type littermates. Overall, our data show that a voltage-gated sodium channel mutation can alter the behavioral response to stress and can interact with the stress response to alter seizure outcome.

Neuropsychological and psychiatric outcomes in poorly controlled idiopathic generalized epilepsy

The neuropsychological and psychiatric outcomes of patients with poorly controlled idiopathic generalized epilepsy (IGE) have not been well characterized. The current study aimed to compare these outcomes to a group of patients with medically refractory temporal lobe epilepsy (TLE). A retrospective review of patients admitted to the epilepsy monitoring unit identified 19 patients with IGE and 23 patients with TLE who underwent neuropsychological and psychiatric evaluations. Patients with IGE required a longer time to complete the Trail Making Tests and had lower performance IQ compared to patients with TLE. Despite a higher burden of convulsions, patients with IGE had lower depression scores on the Beck Depression Inventory-II (BDI-II) than patients with TLE. In the group with IGE, the BDI-II scores were inversely correlated with epilepsy duration. These findings indicate that patients with IGE have lower performance IQ, impaired performance on tests of executive functioning, and lower depression scores compared to patients with TLE, implicating different pathophysiological processes.

Predicting and preventing psychopathology following temporal lobe epilepsy surgery

Less than 3% of temporal lobe epilepsy (TLE) surgical outcome studies have investigated the psychiatric sequelae and morbidity associated with surgery. This is disproportionate to the extent of the problem. Variable prevalence rates have been reported for post-surgical depression, anxiety, and interictal psychosis. Until recently, very few studies distinguished de novo postoperative presentations from pre-existing conditions, making it difficult to accurately assess the impact of TLE surgery on psychiatric morbidity. Predictors of de novo postoperative presentations have proved elusive. This current review summarizes the findings from a systematic literature review of the psychiatric morbidity associated with TLE surgery including newly published follow-up data from our own series of 280 surgical patients. A framework for future research, possible pathophysiological mechanisms, and translational models are also discussed.

Epilepsy and psychiatric comorbidity: a nationally representative population-based study

PURPOSE

In a nationally representative population-based study in England, we estimated the burden of psychiatric and neurodevelopmental comorbidities in people with epilepsy. We investigated whether any overrepresentation of comorbidities could be explained by epilepsy being a chronic medical or neurologic condition, or by the confounding effect of demographic and socioeconomic factors or other health conditions.

METHODS

The Adult Psychiatric Morbidity Survey 2007 comprised detailed interviews with 7,403 individuals living in private households in England. Doctor-diagnosed epilepsy (and asthma, diabetes, and migraine, chronic conditions for comparison) was ascertained by self-report, and extensive diagnostic and screening interviews were used to assess psychiatric and neurodevelopmental conditions.

KEY FINDINGS

The estimated lifetime prevalence of epilepsy in the adult (≥ 16 years old) population of England was 1.2% (95% confidence interval [CI] 1.0-1.5). Almost one-third of the people with epilepsy had an International Classification of Diseases, Tenth Revision (ICD-10) anxiety or depressive disorder (compared with one in six people without epilepsy). Among these, social phobia and agoraphobia, generalized anxiety disorder, depression, and measures of suicidality had strong associations with epilepsy, which remained robust after accounting for potential confounders. These associations were consistently stronger than those in people with asthma or diabetes, and similar to those in people reporting migraine or chronic headaches. Epilepsy was also strongly associated with autism spectrum disorders (odds ratio [OR] 7.4, 95% CI 1.5-35.5) and possible eating disorders, and these associations were not evident in people with asthma, diabetes, or migraine.

SIGNIFICANCE

Psychiatric and neurodevelopmental conditions were overrepresented in people with epilepsy. These associations were stronger than with other nonneurologic chronic conditions, and not explained by confounding. Some overlap in the psychopathology observed in epilepsy and migraine cannot rule out the presence of common pathways of psychiatric comorbidity in neurologic conditions. However, associations of epilepsy with conditions such as autism spectrum disorders point to comorbidities specific to epilepsy that may not be shared by other neurologic conditions.

Evidence for shared susceptibility to epilepsy and psychosis: a population-based family study

BACKGROUND

There is emerging evidence of an etiological overlap between a range of neurodevelopmental disorders, including schizophrenia and epilepsy. Here we investigate shared familial vulnerability to psychotic illness and epilepsy in a family-based study.

METHODS

The study population consisted of parents and their children born in Helsinki between 1947 and 1990. The Finnish Hospital Discharge Register was used to determine psychiatric and neurological outcomes in adulthood for all offspring. Parental history of psychosis and epilepsy was determined by linking the Hospital Discharge Register and the Finnish Population Register.

RESULTS

Our total sample comprised 9653 families and 23,404 offspring. Individuals with epilepsy had a 5.5-fold increase in the risk of having a broadly defined psychotic disorder, an almost 8.5-fold increase in the risk of having schizophrenia, and a 6.3-fold increase in the risk of having bipolar disorder. There was strong evidence of clustering of the association between epilepsy and psychosis within families. Individuals with a parental history of epilepsy had a 2-fold increase in the risk of developing psychosis, compared with individuals without a parental history of epilepsy. Individuals with a parental history of psychosis had, reciprocally, a 2.7-fold increase in the risk of having a diagnosis of generalized epilepsy, compared with individuals without a parental history of psychosis. Post hoc analyses showed that these associations were not driven by the comorbidity of epilepsy and psychosis in the parents.

CONCLUSIONS

These findings support recent evidence of overlapping etiological factors between epilepsy and schizophrenia, especially recent evidence of a genetic overlap between these disorders.

Rapamycin attenuates aggressive behavior in a rat model of pilocarpine-induced epilepsy

Psychiatric disorders are fairly common comorbidities of epilepsy in humans. Following pilocarpine-induced status epilepticus (SE), experimental animals not only developed spontaneous recurrent seizures, but also exhibited significantly elevated levels of aggressive behavior. The cellular and molecular mechanism triggering these behavioral alterations remains unclear. In the present study, we found that aggression is positively correlated with development of spontaneous seizures. Treatment with rapamycin, a potent mTOR (mammalian target of rapamycin pathway)-pathway inhibitor, markedly diminished aggressive behavior. Therefore, the mTOR pathway may have significance in the underlying molecular mechanism leading to aggression associated with epilepsy.

Electrical, molecular and behavioral effects of interictal spiking in the rat

OBJECTIVE

Epilepsy is a disease characterized by chronic seizures, but is associated with significant comorbidities between seizures including cognitive impairments, hyperactivity, and depression. To study this interictal state, we characterized the electrical, molecular, and behavior effects of chronic, neocortical interictal spiking in rats.

METHODS

A single injection of tetanus toxin into somatosensory cortex generated chronic interictal spiking measured by long-term video EEG monitoring and was correlated with motor activity. The cortical pattern of biomarker activation and the effects of blocking MAPK signaling on interictal spiking and behavior were determined.

RESULTS

Interictal spiking in this model increases in frequency, size, and becomes repetitive over time, but is rarely associated with seizures. Interictal spiking was sufficient to produce the same molecular and cellular pattern of layer 2/3-specific CREB activation and plasticity gene induction as is seen in the human interictal state. Increasing spike frequency was associated with hyperactivity, demonstrated by increased ambulatory activity and preferential circling toward the spiking hemisphere. Loud noises induced epileptic discharges, identical to spontaneous discharges. Treatment with a selective MAPK inhibitor prevented layer 2/3 CREB activation, reduced the frequency of epileptic discharges, and normalized behavioral abnormalities, but had no effect on seizures induced by electrical kindling.

INTERPRETATION

These results provide insights into the development of interictal epileptic spiking, their relationship to behavior, and suggest that interictal and ictal activities utilize distinct molecular pathways. This model, that parallels recent observations in humans, will be useful to develop therapeutics against interictal spiking and its behavioral comorbidities.

Epilepsy, mental health disorder, or both?

Temporal lobe epilepsy (TLE), a subset of the seizure disorder family, represents a complex neuropsychiatric illness, where the neurological presentation may be complemented by varying severity of affective, behavioral, psychotic, or personality abnormalities, which, in turn, may not only lead to misdiagnosis, but also affect the management. This paper outlines a spectrum of mental health presentations, including psychosis, mood, anxiety, panic, and dissociative states, associated with epilepsy that make the correct diagnosis a challenge.

Epilepsy and brain inflammation

During the last decade, experimental research has demonstrated a prominent role of glial cells, activated in brain by various injuries, in the mechanisms of seizure precipitation and recurrence. In particular, alterations in the phenotype and function of activated astrocytes and microglial cells have been described in experimental and human epileptic tissue, including modifications in potassium and water channels, alterations of glutamine/glutamate cycle, changes in glutamate receptor expression and transporters, release of neuromodulatory molecules (e.g. gliotransmitters, neurotrophic factors), and induction of molecules involved in inflammatory processes (e.g. cytokines, chemokines, prostaglandins, complement factors, cell adhesion molecules) (Seifert et al., 2006; Vezzani et al., 2011; Wetherington et al., 2008). In particular, brain injury or proconvulsant events can activate microglia and astrocytes to release a number of proinflammatory mediators, thus initiating a cascade of inflammatory processes in brain tissue. Proinflammatory molecules can alter neuronal excitability and affect the physiological functions of glia by paracrine or autocrine actions, thus perturbing the glioneuronal communications. In experimental models, these changes contribute to decreasing the threshold to seizures and may compromise neuronal survival (Riazi et al., 2010; Vezzani et al., 2008). In this context, understanding which are the soluble mediators and the molecular mechanisms crucially involved in glio-neuronal interactions is instrumental to shed light on how brain inflammation may contribute to neuronal hyperexcitability in epilepsy. This review will report the clinical observations in drug-resistant human epilepsies and the experimental findings in adult and immature rodents linking brain inflammation to the epileptic process in a causal and reciprocal manner. By confronting the clinical evidence with the experimental findings, we will discuss the role of specific soluble inflammatory mediators in the etiopathogenesis of seizures, reporting evidence for both their acute and long term effects on seizure threshold. The possible contribution of these mediators to co-morbidities often described in epilepsy patients will be also discussed. Finally, we will report on the anti-inflammatory treatments with anticonvulsant actions in experimental models highlighting possible therapeutic options for treating drug-resistant seizures and for prevention of epileptogenesis.

Antiepileptic drugs in the treatment of psychiatric disorders

The clinical interface between psychiatry and neurology is epilepsy; the pharmacological expression of this interface is antiepileptic drugs (AEDs), as they are used to treat both epilepsy and psychiatric disorders, especially bipolar disorders. The prevalence of psychiatric comorbidity and the risk of suicidal behavior/ideation/suicide are markedly increased in patients with epilepsy (PWE). Though AEDs receive initial indications for the treatment of epilepsy, currently the majority of AEDs are used to treat pain and psychiatric disorders. Thus in selecting the appropriate AEDs for treatment of PWE, consideration should be given to which AEDs best treat the epileptic disorder and the psychiatric comorbidity. This review is an overview of 21 AEDs in which negative psychotropic properties, approved indications in psychiatry, off-label studied uses in psychiatry, and principal uses in psychiatry are presented with literature review. A total of 40 psychiatric uses have been identified. Of the 21 AEDs reviewed, only 5 have U.S. Food and Drug Administration and/or European Medicines Agency psychiatric approval for limited uses; the majority of AEDs are used off-label. Many of these off-label uses are based on case reports, open-label studies, and poorly controlled or small-sample-size studies. In some instances, off-label use persists in the face of negative pivotal trials. Further placebo-controlled (augmentation and monotherapy) parallel-arm research with active comparators is required in the complex field of AED treatment of psychiatric disorders to minimize the treatment gap not only for PWE with psychiatric disorders, but also for psychiatric patients who would benefit from properly studied AEDs while minimizing adverse effects.

Psychogenic nonepileptic seizures and suicidal behavior on a video/EEG telemetry unit: the need for psychiatric assessment and screening for suicide risk

Patients with epilepsy and psychogenic nonepileptic seizures (PNES) have an increased prevalence of psychiatric illness and risk for suicidal ideation/suicidal behavior/suicide compared with the general population. Recent literature suggests that antiepileptic drugs (AEDs) used to treat epilepsy, pain, and psychiatric disorders increase the risk of suicide and that this increased risk may be AED selective. This case analyzes a suicide attempt on a video/EEG telemetry unit. Specific risk factors associated with increased risk of suicidal behaviors pertinent to this case are reviewed: epilepsy, multiple psychiatric diagnoses including affective disorder, AEDs, PNES, prior medically serious suicide attempt, and suicide attempt within the past month. Specific psychometric rating scales to screen for both psychiatric illness and suicide risk and psychiatric assessment should be integral components of the evaluation and treatment of patients on video/EEG telemetry units.

Psychometric Attributes of the DISC Predictive Scales

Introduction:

This study was designed to evaluate the psychometric attributes and screening efficiency of a Spanish version of the Children Predictive Scales (DPS) against the Spanish Diagnostic Interview Schedule for Children (DISC-IV).

Method:

This pilot cross-sectional study included 61 children aged 9 to 14 years in a mainstream school. The following psychometric attributes were analyzed: acceptability, scale assumptions, internal consistency, and precision, as well the predictive validity (AUC).

Results:

The scale did not show ceiling or floor effects (6.4%, 1.3%, respectively). The internal consistency was high (α=0.92), and the standard error of measurement was adequate (SEM=1.54). The overall DPS AUC was 0.72 against DISC IV corresponding diagnosis.

Conclusion:

The Spanish version of the DPS-4.32 seems to be a reliable and precise tool for screening mental health disorders in a school-age population.