Epilepsy in patients with schizophrenia: Pathophysiology and basic treatments

Clozapine Use Among Individuals With Schizophrenia Occurring on the Background of Intellectual Disability and Rare Genetic Variation: A Retrospective Chart Review

BACKGROUND

Treatment resistance in schizophrenia is associated with both intellectual disability and rare genetic variation. Information pertaining to the use of clozapine in this context has primarily come from case reports and small case series. Given the frequent occurrence of comorbid medical issues in various genetic disorders and the heightened sensitivity to antipsychotic medications among intellectually disabled individuals, additional information regarding the effectiveness and tolerability of clozapine in this population is needed, particularly in light of its unique side effect profile.

METHODS

This retrospective review of 1200 charts, which took place at a subspecialty psychiatry clinic, sought to characterize the use of clozapine in individuals with schizophrenia (or psychotic symptoms, generally speaking) and intellectual disability occurring on the background of rare genetic variation, a difficult to study and underserved patient population.

RESULTS

Twelve hundred charts were reviewed and 10 eligible individuals were identified, all of whom had been prescribed clozapine and carried a diagnosis of schizophrenia on the background of intellectual disability and rare genetic variation. Six of these 10 individuals harbored presumed pathogenic variants.

IMPLICATIONS

This study affirms what is known about clozapine treatment in 22q11.2 deletion syndrome, adds to the scarce literature on Usher syndrome in this context, and provides the first accounts of clozapine use in 22q11.2 microduplication syndrome and DCX variant-related heterotopia.

Safety of rTMS for Schizophrenia: A Systematic Review and Meta-analysis

BACKGROUND AND HYPOTHESIS

Current treatments for schizophrenia are only partially effective, and there are no medications for negative symptoms or cognitive impairment. Neuromodulation, such as repetitive transcranial magnetic stimulation (rTMS), has potential as a novel intervention for schizophrenia. Prior to clinical use, rTMS should have demonstrated safety in a large schizophrenia population. However, the safety profile of rTMS in schizophrenia is not well characterized, and regulatory agencies have expressed concern about safety in this population.

STUDY DESIGN

We conducted a systematic review with meta-analysis of rTMS studies in schizophrenia. We searched PubMed, the Cochrane Library, PsycINFO, and Science Citation Index Expanded for rTMS studies in schizophrenia that reported adverse effects. We extracted the number of participants who experienced an adverse effect and calculated the prevalence of each adverse effect for active or sham rTMS. We tested the difference between the prevalence of events in the active and sham conditions. We assessed risk of bias using the Cochrane Handbook.

STUDY RESULTS

The initial search identified 1472 studies. After screening, 261 full-text studies were assessed, and 126 met inclusion criteria (N = 4122 total subjects). The prevalence of headache or scalp pain, dizziness or syncope, facial twitching, and nausea was higher for active rTMS compared to sham (P < .05). The prevalence of all other adverse effects, including seizure, was not different between active and sham rTMS.

CONCLUSIONS

rTMS is safe and well tolerated for people with schizophrenia. Individuals with schizophrenia are not at increased risk for adverse effects, including seizure, compared to the general population.

Proposal for a Novel Classification of Patients With Enlarged Ventricles and Cognitive Impairment Based on Data-Driven Analysis of Neuroimaging Results in Patients With Psychiatric Disorders

One of the challenges in diagnosing psychiatric disorders is that the results of biological and neuroscience research are not reflected in the diagnostic criteria. Thus, data-driven analyses incorporating biological and cross-disease perspectives, regardless of the diagnostic category, have recently been proposed. A data-driven clustering study based on subcortical volumes in 5604 subjects classified into four brain biotypes associated with cognitive/social functioning. Among the four brain biotypes identified in controls and patients with schizophrenia, bipolar disorder, major depressive disorder, autism spectrum disorder, and other psychiatric disorders, we further analyzed the brain biotype 1 subjects, those with an extremely small limbic region, for clinical utility. We found that the representative feature of brain biotype 1 is enlarged lateral ventricles. An enlarged ventricle, defined by an average z-score of left and right lateral ventricle volumes > 3, had a sensitivity of 99.1% and a specificity of 98.1% for discriminating brain biotype 1. However, the presence of an enlarged ventricle was not sufficient to classify patient subgroups, as 1% of the controls also had enlarged ventricles. Reclassification of patients with enlarged ventricles according to cognitive impairment resulted in a stratified subgroup that included patients with a high proportion of schizophrenia diagnoses, electroencephalography abnormalities, and rare pathological genetic copy number variations. Data-driven clustering analysis of neuroimaging data revealed subgroups with enlarged ventricles and cognitive impairment. This subgroup could be a new diagnostic candidate for psychiatric disorders. This concept and strategy may be useful for identifying biologically defined psychiatric disorders in the future.

Effectiveness of antipsychotic drug therapy for treating psychosis in people with epilepsy: A systematic review

Individuals with epilepsy are at risk of developing preictal, ictal, postictal and interictal psychoses. Antipsychotic drugs (APDs) are the main class of drugs used to treat psychosis and schizophrenia. The efficacy and safety of APDs as a treatment for epileptic psychosis is not well understood. This systematic review aimed to assess the effectiveness and adverse effects of APDs for treating psychosis in people with epilepsy. We adhered to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. We searched MEDLINE, Embase, PsycInfo, and AMED (Allied and Complementary Medicine) from database inception to June 20, 2023. We contacted experts in the field and performed citation searches to identify additional records. Title, abstract, full-text review, and data analysis were conducted in duplicate, with conflicts resolved by discussion among authors. Given the considerable heterogeneity of study designs, meta-analysis was not deemed appropriate; instead, the results were tabulated in a narrative synthesis. The Joanna Briggs Institute Risk of Bias tool and GRADE (Grading of Recommendations Assessment, Development, and Evaluation) framework were used to assess study quality. We identified 13 studies with a total of 1180 participants. In the four case series included, the psychotic symptoms of 25 of 28 patients treated with APDs partially improved or fully resolved. Three of the four cohort studies reported an association between antipsychotic use and longer duration of psychotic episodes, two found similar results in both APD and non-APD groups, and two did not report control psychosis outcomes. When reported, seizure frequency was observed to remain unchanged or decrease following APD treatment. The evidence on the effectiveness of antipsychotics in the treatment of psychosis in epilepsy is inconclusive and may reflect confounding by indication. However, most studies suggest that antipsychotics were not associated with a marked worsening in seizure frequency. It remains unclear whether antipsychotics should be used in epilepsy, and well-controlled cohort studies and randomized controlled trials are necessary to draw definitive conclusions.

Associations between neurolinguistic deficits and personality traits in people with epilepsy

Introduction

People with epilepsy (PWE) have been hypothesized to have higher prevalence of personality disorders and cognitive disorders. The objective of this study was to investigate the controversial notion of "epileptic personality," a series of supposedly specific personality traits of people with epilepsy (PWE).

Methods

For this purpose, 29 individuals with Mesial Temporal lobe Epilepsy (MTLE) and 23 with Juvenile myoclonic epilepsy (JME) as confirmed by electroencephalography (EEG), MRI scans and clinical examination, underwent a thorough neuropsychological and personality assessment. The resulting neuropsychological profiles were statistically analyzed considering possible personality disorders, character traits, cognitive and linguistic deviations from 20 healthy controls (HC).

Results

Our findings suggest accumulative cognitive and linguistic deficits in individuals with epilepsy compared to controls. It is possible that these might be misinterpreted as personality disorders. Specifically, personality traits (p = 0.049) and verbal fluency (p = 0.013), were significantly different between PWEs and controls. Also, the type of epilepsy and lateralization seem to affect executive function (p = 0.049) and pragmatology scores (p < 0.001), exhibiting differences in subgroup analysis.

Discussion

Different theories are considered as plausible pathophysiological explanations for the aforementioned differences. This research might serve as a basis to further investigate the cognitive aspects of epilepsy and possible pharmacological interventions, which are currently lacking.

Catatonia and epilepsy: An underappreciated relationship

Catatonia is currently conceived in the major diagnostic manuals as a syndrome with a range of possible psychiatric and general medical underlying conditions. It features diverse clinical signs, spanning motor, verbal and behavioural domains and including stupor, catalepsy, mutism, echolalia, negativism and withdrawal. The existing literature suggests that seizure activity may underlie catatonia in approximately 2% of cases. There are three possible temporal relationships between catatonia and seizure activity: (1) ictal catatonia, in which catatonia is a presentation of non-convulsive status epilepticus; (2) postictal catatonia, in which catatonia follows a seizure, and (3) interictal catatonia, in which catatonia and seizures occur in the same individual without any clear temporal relationship between them. Electroencephalographic (EEG) abnormalities are common in catatonia, even in those cases with a presumed primary psychiatric origin, and often consist of generalised background slowing. Paradoxically, electroconvulsive therapy is an effective treatment for catatonia. There are several converging pieces of evidence suggesting that there may be underlying seizure activity in more cases of catatonia than has hitherto been recognised, though identification of these seizures may require intracranial EEG recording.

The neuropsychological presentation of women with epilepsy: Clinical considerations and future directions

Objective: Cognitive, mood, and behavioral changes are common among persons with epilepsy (PWE), resulting in a complex neuropsychological presentation. Women with epilepsy (WWE) represent a distinct cohort within the broader epilepsy population due to sex and gender-specific factors impacting epilepsy semiology and treatment. However, unique neuropsychological profiles among WWE have not been established. This narrative review aims to further define neuropsychological correlates in WWE and promote meaningful discussion related to enhancing the provision of neuropsychological care within this clinical population. Method: Current literature in PWE examining differences in cognitive function, mental health, and quality of life (QoL) between women and men was critically reviewed, emphasizing considerations for neuropsychological practice. Results: WWE demonstrate a preservation of verbal learning and memory compared to men both pre- and post-surgically, with sex-based, neurobiological mechanisms likely contributing to this association. WWE also have elevated risk for affective disorder psychopathology, suicidality, and traumatic experiences. Epidemiology related to psychotic and bipolar spectrum disorders is less clear, and findings are mixed regarding sex-specific behavioral side effects of antiseizure and psychotropic medication. Finally, hormonal and obstetric factors are highlighted as important contributors to neuropsychological symptoms in WWE, with elevated risk for low QoL and increased stigma associated with greater medical and psychiatric comorbidities compared to men. Conclusions: While emerging literature has begun to characterize the neuropsychological presentation of WWE, future research is needed to define sex and gender differences in neuropsychological sequalae among PWE to ensure consistency and quality of care for WWE.

Systems Genetics Analyses Reveals Key Genes Related to Behavioral Traits in the Striatum of CFW Mice

The striatum plays a central role in directing many complex behaviors ranging from motor control to action choice and reward learning. In our study, we used 55 male CFW mice with rapid decay linkage disequilibrium to systematically mine the striatum-related behavioral functional genes by analyzing their striatal transcriptomes and 79 measured behavioral phenotypic data. By constructing a gene coexpression network, we clustered the genes into 13 modules, with most of them being positively correlated with motor traits. Based on functional annotations as well as Fisher's exact and hypergeometric distribution tests, brown and magenta modules were identified as core modules. They were significantly enriched for striatal-related functional genes. Subsequent Mendelian randomization analysis verified the causal relationship between the core modules and dyskinesia. Through the intramodular gene connectivity analysis, Adcy5 and Kcnma1 were identified as brown and magenta module hub genes, respectively. Knock outs of both Adcy5 and Kcnma1 lead to motor dysfunction in mice, and KCNMA1 acts as a risk gene for schizophrenia and smoking addiction in humans. We also evaluated the cellular composition of each module and identified oligodendrocytes in the striatum to have a positive role in motor regulation.

Integrating Electronic Health Records and Polygenic Risk to Identify Genetically Unrelated Comorbidities of Schizophrenia That May Be Modifiable

Background

Patients with schizophrenia have substantial comorbidity that contributes to reduced life expectancy of 10 to 20 years. Identifying modifiable comorbidities could improve rates of premature mortality. Conditions that frequently co-occur but lack shared genetic risk with schizophrenia are more likely to be products of treatment, behavior, or environmental factors and therefore are enriched for potentially modifiable associations.

Methods

Phenome-wide comorbidity was calculated from electronic health records of 250,000 patients across 2 independent health care institutions (Vanderbilt University Medical Center and Mass General Brigham); associations with schizophrenia polygenic risk scores were calculated across the same phenotypes in linked biobanks.

Results

Schizophrenia comorbidity was significantly correlated across institutions (r = 0.85), and the 77 identified comorbidities were consistent with prior literature. Overall, comorbidity and polygenic risk score associations were significantly correlated (r = 0.55, p = 1.29 × 10-118). However, directly testing for the absence of genetic effects identified 36 comorbidities that had significantly equivalent schizophrenia polygenic risk score distributions between cases and controls. This set included phenotypes known to be consequences of antipsychotic medications (e.g., movement disorders) or of the disease such as reduced hygiene (e.g., diseases of the nail), thereby validating the approach. It also highlighted phenotypes with less clear causal relationships and minimal genetic effects such as tobacco use disorder and diabetes.

Conclusions

This work demonstrates the consistency and robustness of electronic health record-based schizophrenia comorbidities across independent institutions and with the existing literature. It identifies known and novel comorbidities with an absence of shared genetic risk, indicating other causes that may be modifiable and where further study of causal pathways could improve outcomes for patients.

Delineating mechanisms underlying parvalbumin neuron impairment in different neurological and neurodegenerative disorders: the emerging role of mitochondrial dysfunction

Given the current paucity of effective treatments in many neurological disorders, delineating pathophysiological mechanisms among the major psychiatric and neurodegenerative diseases may fuel the development of novel, potent treatments that target shared pathways. Recent evidence suggests that various pathological processes, including bioenergetic failure in mitochondria, can perturb the function of fast-spiking, parvalbumin-positive neurons (PV+). These inhibitory neurons critically influence local circuit regulation, the generation of neuronal network oscillations and complex brain functioning. Here, we survey PV+ cell vulnerability in the major neuropsychiatric, and neurodegenerative diseases and review associated cellular and molecular pathophysiological alterations purported to underlie disease aetiology.

Schizophrenia and epileptic comorbidity

Epileptic seizures have been widely considered as a complication of external or iatrogenic factors in schizophrenia. However, epidemiologic, neurodevelopmental and genetic data have changed regards on this topic considering the complexity of the bidirectional link between epilepsy and schizophrenia. We will examine these data constituting the pathophysiological aspects of this particular association and detail the particular impact of antipsychotics on the occurence of epileptic seizure in schizophrenia as well as the management strategies.

Medication compliance of children with epilepsy: a cross-sectional survey

BACKGROUND

Good medication compliance is very important for the prognosis of children with epilepsy. We aimed to evaluate the status and influencing factors of medication compliance in children with epilepsy and to provide insights to the clinical nursing care of children with epilepsy.

METHODS

We selected epileptic children admitted to Children's Hospital of Nanjing Medical University from February 1, 2022 to August 31, 2022. Self-designed questionnaire and medication compliance scale were used to evaluate the characteristics and medication compliance of children with epilepsy. Pearson correlation analysis and multivariate logistic regression were used to analyze the influencing factors of medication compliance.

RESULTS

A total of 156 children with epilepsy were included, the incidence of poor compliance in children with epilepsy was 37.18%. Pearson correlation analysis indicated that age(r = 0.622), courses of epilepsy(r = 0.553), parental education level(r = 0.506), monthly household income(r = 0.652) and number of drugs taken(r = 0.577) were correlated with the compliance(all P<0.05). Logistic regression analyses indicated that age ≤ 6 y(OR = 2.104, 95%CI: 1.712 ~ 2.527), courses of epilepsy ≤ 3 years(OR = 2.661, 95%CI: 2.089 ~ 2.941), low parental education level(OR = 1.977, 95%CI: 1.314 ~ 2.351), monthly household income ≤ 5000 RMB(OR = 2.812, 95%CI: 2.194 ~ 3.181), number of drugs taken ≥ 3(OR = 3.025, 95%CI: 2.336 ~ 3.475) were the influencing factors of medication compliance in children with epilepsy(all P<0.05).

CONCLUSIONS

The medication compliance of children with epilepsy needs to be improved, and the medication compliance of children is affected by age, courses of epilepsy, parental education level, monthly household income and number of drugs taken. Clinical medical personnel take targeted nursing measures against these factors to improve the medication compliance of children with epilepsy.

Animal Models of Hypertension (ISIAH Rats), Catatonia (GC Rats), and Audiogenic Epilepsy (PM Rats) Developed by Breeding

Research into genetic and physiological mechanisms of widespread disorders such as arterial hypertension as well as neuropsychiatric and other human diseases is urgently needed in academic and practical medicine and in the field of biology. Nevertheless, such studies have many limitations and pose difficulties that can be overcome by using animal models. To date, for the purposes of creating animal models of human pathologies, several approaches have been used: pharmacological/chemical intervention; surgical procedures; genetic technologies for creating transgenic animals, knockouts, or knockdowns; and breeding. Although some of these approaches are good for certain research aims, they have many drawbacks, the greatest being a strong perturbation (in a biological system) that, along with the expected effect, exerts side effects in the study. Therefore, for investigating the pathogenesis of a disease, models obtained using genetic selection for a target trait are of high value as this approach allows for the creation of a model with a "natural" manifestation of the pathology. In this review, three rat models are described: ISIAH rats (arterial hypertension), GC rats (catatonia), and PM rats (audiogenic epilepsy), which are developed by breeding in the Laboratory of Evolutionary Genetics at the Institute of Cytology and Genetics (the Siberian Branch of the Russian Academy of Sciences).

Identifying modifiable comorbidities of schizophrenia by integrating electronic health records and polygenic risk

Patients with schizophrenia have substantial comorbidity contributing to reduced life expectancy of 10-20 years. Identifying which comorbidities might be modifiable could improve rates of premature mortality in this population. We hypothesize that conditions that frequently co-occur but lack shared genetic risk with schizophrenia are more likely to be products of treatment, behavior, or environmental factors and therefore potentially modifiable. To test this hypothesis, we calculated phenome-wide comorbidity from electronic health records (EHR) in 250,000 patients in each of two independent health care institutions (Vanderbilt University Medical Center and Mass General Brigham) and association with schizophrenia polygenic risk scores (PRS) across the same phenotypes (phecodes) in linked biobanks. Comorbidity with schizophrenia was significantly correlated across institutions (r = 0.85) and consistent with prior literature. After multiple test correction, there were 77 significant phecodes comorbid with schizophrenia. Overall, comorbidity and PRS association were highly correlated (r = 0.55, p = 1.29×10-118), however, 36 of the EHR identified comorbidities had significantly equivalent schizophrenia PRS distributions between cases and controls. Fifteen of these lacked any PRS association and were enriched for phenotypes known to be side effects of antipsychotic medications (e.g., "movement disorders", "convulsions", "tachycardia") or other schizophrenia related factors such as from smoking ("bronchitis") or reduced hygiene (e.g., "diseases of the nail") highlighting the validity of this approach. Other phenotypes implicated by this approach where the contribution from shared common genetic risk with schizophrenia was minimal included tobacco use disorder, diabetes, and dementia. This work demonstrates the consistency and robustness of EHR-based schizophrenia comorbidities across independent institutions and with the existing literature. It identifies comorbidities with an absence of shared genetic risk indicating other causes that might be more modifiable and where further study of causal pathways could improve outcomes for patients.

Comparison of Oncogenes, Tumor Suppressors, and MicroRNAs Between Schizophrenia and Glioma: The Balance of Power

The risk of cancer in schizophrenia has been controversial. Confounders of the issue are cigarette smoking in schizophrenia, and antiproliferative effects of antipsychotic medications. The author has previously suggested comparison of a specific cancer like glioma to schizophrenia might help determine a more accurate relationship between cancer and schizophrenia. To accomplish this goal, the author performed three comparisons of data; the first a comparison of conventional tumor suppressors and oncogenes between schizophrenia and cancer including glioma. This comparison determined schizophrenia has both tumor-suppressive and tumor-promoting characteristics. A second, larger comparison between brain-expressed microRNAs in schizophrenia with their expression in glioma was then performed. This identified a core carcinogenic group of miRNAs in schizophrenia offset by a larger group of tumor-suppressive miRNAs. This proposed "balance of power" between oncogenes and tumor suppressors could cause neuroinflammation. This was assessed by a third comparison between schizophrenia, glioma and inflammation in asbestos-related lung cancer and mesothelioma (ALRCM). This revealed that schizophrenia shares more oncogenic similarity to ALRCM than glioma.

Bidirectionality of antiseizure and antipsychotic treatment: A population-based study

PURPOSE

To study the prevalence and directionality of comorbid epilepsy and psychosis in Norway.

METHODS

The Norwegian Prescription Database (NorPD) provided individual-based information on all antiseizure medications (ASMs) and antipsychotic drugs (APDs) dispensed during 2004-2017. Subjects were ≥18 years of age at the end of the study period. Diagnosis-specific reimbursement codes from the 10th revision of the International Classification of Diseases/2nd edition of the International Classification of Primary Care (ICD-10/ICPC-2) combined with ATC codes were used as indicators of diagnosis. Subjects had collected ASMs for epilepsy or APDs for psychosis at least four times, at least once issued with an ICD-10 code from the specialist healthcare service. Directionality was analyzed in subjects receiving both treatments. To reduce prevalent comorbidity bias, we employed a four-year comorbidity-free period (2004-2007). The use of specific ASMs and APDs was analyzed.

RESULTS

A total of 31,289 subjects had collected an ASM for epilepsy at least four times, 28,889 an APD for psychosis. Both the prevalence of treatment for epilepsy and of treatment for psychosis was 0.8%. Further, 891 subjects had been treated for both conditions; 2.8% with epilepsy had been treated for psychosis, and 3.1% with psychosis had been treated for epilepsy. Among 558 subjects included in the analyses of directionality, 56% had collected the first APD before an ASM, whereas 41% had collected an ASM first. During the last year prior to comorbidity onset, levetiracetam, topiramate, or zonisamide had been used for epilepsy by approximately 40%, whereas olanzapine and quetiapine were most used in patients with psychosis, and clozapine in 13%.

CONCLUSION

The proportion of patients with prior antipsychotic treatment at onset of epilepsy is higher than previously acknowledged, as demonstrated in this nation-wide study. Apart from a shared neurobiological susceptibility, the bidirectionality of epilepsy and psychosis may be influenced by various environmental factors, including the interaction of pharmacodynamic effects. APDs may facilitate seizures; ASMs may induce psychiatric symptoms. In patients with combined treatment, these potential drug effects should receive ample attention, along with the psychosocial consequences of the disorders. A prudent multi-professional approach is required.