A prospective study of smoking, caffeine, and alcohol as risk factors for seizures or epilepsy in young adult women: data from the Nurses' Health Study II

Alterations in DNA 5-hydroxymethylation patterns in the hippocampus of an experimental model of chronic epilepsy

Temporal lobe epilepsy (TLE) is a type of focal epilepsy characterized by spontaneous recurrent seizures originating from the hippocampus. The epigenetic reprogramming hypothesis of epileptogenesis suggests that the development of TLE is associated with alterations in gene transcription changes resulting in a hyperexcitable network in TLE. DNA 5-methylcytosine (5-mC) is an epigenetic mechanism that has been associated with chronic epilepsy. However, the contribution of 5-hydroxymethylcytosine (5-hmC), a product of 5-mC demethylation by the Ten-Eleven Translocation (TET) family proteins in chronic TLE is poorly understood. 5-hmC is abundant in the brain and acts as a stable epigenetic mark altering gene expression through several mechanisms. Here, we found that the levels of bulk DNA 5-hmC but not 5-mC were significantly reduced in the hippocampus of human TLE patients and in the kainic acid (KA) TLE rat model. Using 5-hmC hMeDIP-sequencing, we characterized 5-hmC distribution across the genome and found bidirectional regulation of 5-hmC at intergenic regions within gene bodies. We found that hypohydroxymethylated 5-hmC intergenic regions were associated with several epilepsy-related genes, including Gal, SV2, and Kcnj11 and hyperdroxymethylation 5-hmC intergenic regions were associated with Gad65, TLR4, and Bdnf gene expression. Mechanistically, Tet1 knockdown in the hippocampus was sufficient to decrease 5-hmC levels and increase seizure susceptibility following KA administration. In contrast, Tet1 overexpression in the hippocampus resulted in increased 5-hmC levels associated with improved seizure resiliency in response to KA. These findings suggest an important role for 5-hmC as an epigenetic regulator of epilepsy that can be manipulated to influence seizure outcomes.

Caffeine and Its Interactions with Antiseizure Medications-Is There a Correlation between Preclinical and Clinical Data?

Experimental studies reveal that caffeine (trimethylxanthine) at subconvulsive doses, distinctly reduced the anticonvulsant activity of numerous antiseizure medications (ASMs) in rodents, oxcarbazepine, tiagabine and lamotrigine being the exceptions. Clinical data based on low numbers of patients support the experimental results by showing that caffeine (ingested in high quantities) may sharply increase seizure frequency, considerably reducing the quality of patients' lives. In contrast, this obviously negative activity of caffeine was not found in clinical studies involving much higher numbers of patients. ASMs vulnerable to caffeine in experimental models of seizures encompass carbamazepine, phenobarbital, phenytoin, valproate, gabapentin, levetiracetam, pregabalin and topiramate. An inhibition of R-calcium channels by lamotrigine and oxcarbazepine may account for their resistance to the trimethylxanthine. This assumption, however, is complicated by the fact that topiramate also seems to be a blocker of R-calcium channels. A question arises why large clinical studies failed to confirm the results of experimental and case-report studies. A possibility exists that the proportion of patients taking ASMs resistant to caffeine may be significant and such patients may be sufficiently protected against the negative activity of caffeine.

Alterations in DNA 5-hydroxymethylation Patterns in the Hippocampus of an Experimental Model of Refractory Epilepsy

Temporal lobe epilepsy (TLE) is a type of focal epilepsy characterized by spontaneous recurrent seizures originating from the hippocampus. The epigenetic reprogramming hypothesis of epileptogenesis suggests that the development of TLE is associated with alterations in gene transcription changes resulting in a hyperexcitable network in TLE. DNA 5-methylcytosine (5-mC) is an epigenetic mechanism that has been associated with chronic epilepsy. However, the contribution of 5-hydroxymethylcytosine (5-hmC), a product of 5-mC demethylation by the Ten-Eleven Translocation (TET) family proteins in chronic TLE is poorly understood. 5-hmC is abundant in the brain and acts as a stable epigenetic mark altering gene expression through several mechanisms. Here, we found that the levels of bulk DNA 5-hmC but not 5-mC were significantly reduced in the hippocampus of human TLE patients and in the kainic acid (KA) TLE rat model. Using 5-hmC hMeDIP-sequencing, we characterized 5-hmC distribution across the genome and found bidirectional regulation of 5-hmC at intergenic regions within gene bodies. We found that hypohydroxymethylated 5-hmC intergenic regions were associated with several epilepsy-related genes, including Gal , SV2, and Kcnj11 and hyperdroxymethylation 5-hmC intergenic regions were associated with Gad65 , TLR4 , and Bdnf gene expression. Mechanistically, Tet1 knockdown in the hippocampus was sufficient to decrease 5-hmC levels and increase seizure susceptibility following KA administration. In contrast, Tet1 overexpression in the hippocampus resulted in increased 5-hmC levels associated with improved seizure resiliency in response to KA. These findings suggest an important role for 5-hmC as an epigenetic regulator of epilepsy that can be manipulated to influence seizure outcomes.

Causal relationship between addictive behaviors and epilepsy risk: A mendelian randomization study

BACKGROUND

Previous studies have reported inconsistent results regarding the potential relationships between addictive behaviors and the risk of epilepsy.

OBJECTIVE

To assess whether genetically predicted addictive behaviors are causally associated with the risk of epilepsy outcomes.

METHODS

The causation between five addictive behaviors (including cigarettes per day, alcoholic drinks per week, tea intake, coffee intake, and lifetime cannabis use) and epilepsy was evaluated by using a two-sample Mendelian Randomization (MR) analysis. The inverse-variance weighted (IVW) method was used as the primary outcome. The other MR analysis methods (MR Egger, weighted median, simulation extrapolation corrected MR-Egger, and Mendelian Randomization Pleiotropy Residual Sum and Outlier (MR-PRESSO)) were performed to complement IVW. In addition, the robustness of the MR analysis results was assessed by leave-one-out analysis.

RESULTS

The IVW analysis method indicated an approximately 20% increased risk of epilepsy per standard deviation increase in lifetime cannabis use (odds ratio [OR], 1.20; 95% confidence interval [CI]), 1.02-1.42, P = 0.028). However, there is no causal association between the other four addictive behaviors and the risk of epilepsy (cigarettes per day: OR, 1.04; 95% CI, 0.92-1.18, P = 0.53; alcoholic drinks per week: OR, 1.31; 95% CI, 0.93-1.84, P = 0.13; tea intake: OR, 1.15; 95% CI, 0.84-1.56, P = 0.39; coffee intake: OR, 0.86; 95% CI, 0.59-1.23, P = 0.41). The other MR analysis methods and further leave-one-out sensitivity analysis suggested the results were robust.

CONCLUSION

This MR study indicated a potential genetically predicted causal association between lifetime cannabis use and higher risk of epilepsy. As for the other four addictive behaviors, no evidence of a causal relationship with the risk of epilepsy was found in this study.

Third-Generation Antiseizure Medication in the Treatment of Benzodiazepine-Refractory Status Epilepticus in Poststroke Epilepsy: A Retrospective Observational Register-Based Study

BACKGROUND AND OBJECTIVE

Status epilepticus in poststroke epilepsy is a challenging condition because of multiple vascular comorbidities and the advanced age of patients. Data on third-generation antiseizure medication (ASM) in this condition are limited. The aim of this study was to evaluate the efficacy of third-generation ASMs in the second- or third-line therapy of benzodiazepine-refractory status epilepticus in poststroke epilepsy following acute ischemic stroke.

METHODS

Data on the effectiveness of third-generation ASMs in patients with status epilepticus in poststroke epilepsy were gathered from two German Stroke Registries and the Mainz Epilepsy Registry. We included only cases with epilepsy remote to the ischemic event. No patients with acute symptomatic seizures were included. The following third-generation ASMs were included: brivaracetam, lacosamide, eslicarbazepine, perampanel, topiramate, and zonisamide. The assessment of effectiveness was based on seizure freedom within 48 h since the start of therapy with the respective ASM. Seizure freedom was evaluated both clinically (clinical evaluation at least three times per day) and by daily electroencephalogram records.

RESULTS

Of the 138 patients aged 70.8 ± 8.1 years with benzodiazepine-refractory status epilepticus in ischemic poststroke epilepsy, 33 (23.9%) were treated with lacosamide, 24 (17.4%) with brivaracetam, 23 (16.7%) with eslicarbazepine, 21 (15.2%) with perampanel, 20 (14.5%) with topiramate, and 17 (12.3%) with zonisamide. Seizure freedom within 48 h was achieved in 66.7% of patients with lacosamide, 65.2% with eslicarbazepine, 38.1% with perampanel, 37.5% with brivaracetam, 35.0% with topiramate, and 35.3% with zonisamide (p < 0.05 for comparison of lacosamide or eslicarbazepine to other ASMs).

CONCLUSIONS

Based on these data, lacosamide and eslicarbazepine might be more favorable in the treatment of refractory status epilepticus in poststroke epilepsy, when administered as second- or third-line ASMs before anesthesia. Because of the fact that these ASMs share the same mechanism of action (slow inactivation of sodium channels), our findings could motivate further research on the role that this pharmaceutical mechanism of action has in the treatment of poststroke epilepsy.

CLINICAL TRIAL REGISTRATION

This study was registered at ClinicalTrials.gov (NCT05267405).

How do smoking, vaping, and nicotine affect people with epilepsy and seizures? A scoping review protocol

BACKGROUND

Epilepsy is a prevalent disease that requires personalized care to control seizures, reduce side effects, and ameliorate the burden of comorbidities. Smoking is a major cause of preventable death and disease. There is evidence that patients with epilepsy smoke at high rates and that smoking may increase seizure frequency. However, there is a lack systematically synthesized evidence on the interactions between epilepsy and seizures and smoking, tobacco use, vaping, and smoking cessation.

METHODS AND ANALYSIS

This scoping review protocol guided by the Joanna Briggs Institute Manual for Evidence Synthesis and the PRISMA Extension for Scoping Reviews will investigate what is known about the interactions between smoking and epilepsy. This review will include the population of persons with all types of epilepsy or seizures and examine an inclusive list of concepts including tobacco use, vaping, nicotine replacement, and smoking cessation. The MEDLINE, Embase, APA Psycinfo, CINAHL, Cochrane, Scopus, and Web of Science databases will be searched. Following systematic screening of records, data will be charted, synthesized, and summarized for presentation and publication.

ETHICS AND DISSEMINATION

No ethical approval is required for this literature-based study. The results of this scoping review will be submitted for publication in a peer-reviewed journal. This synthesis will be informative to clinicians and direct further research that may improve health outcomes for people with epilepsy.

REGISTRATION

This protocol is registered with the Open Science Framework (DOI: https://doi.org/10.17605/OSF.IO/D3ZK8).

Effect of Carbon Monoxide Poisoning on Epilepsy Development: A Nationwide Population-Based Cohort Study

STUDY OBJECTIVE

Carbon monoxide (CO) poisoning causes central nervous system toxicity resulting in delayed neurologic sequelae. This study aims to evaluate the risk of epilepsy in patients with a history of CO intoxication.

METHODS

We conducted a retrospective population-based cohort study using the Taiwan National Health Insurance Research Database and enrolled patients with and without CO poisoning matched for age, sex, and index year in a 1:5 ratio, between 2000 and 2010. Multivariable survival models were used to assess the risk of epilepsy. The primary outcome was newly developed epilepsy after the index date. All patients were followed until a new diagnosis of epilepsy, death, or December 31, 2013. Stratification analyses by age and sex were also conducted.

RESULTS

This study included 8,264 patients with CO poisoning and 41,320 without. Patients with a history of CO poisoning were strongly associated with subsequent epilepsy (adjusted hazard ratio [HR] 8.40; 95% confidence interval [CI], 6.48 to 10.88). In the age-stratified analysis, intoxicated patients aged 20 to 39 years had the highest HR (adjusted HR 11.06; 95% CI, 7.17 to 17.08). In the sex-stratified analysis, adjusted HRs for male and female patients were 8.00 (95% CI, 5.86 to 10.92) and 9.53 (95% CI, 5.95 to 15.26), respectively.

CONCLUSION

Patients with CO poisoning were associated with an increased risk of developing epilepsy compared with those without CO poisoning. This association was more prominent in the young population.

Morbidity and rehospitalization postpartum among women with epilepsy and their infants: A population-based study

OBJECTIVE

We compared the relative occurrence of selected pregnancy outcomes and postpartum rehospitalizations among women with and without epilepsy and their infants. Using linked vital-hospital discharge records of women with deliveries in Washington State 1987-2014, comparisons were made overall, by epilepsy type, and by time periods related to antiepileptic drug (AED) marketing changes.

METHODS

This population-based retrospective cohort study identified women with, and without epilepsy per diagnosis codes in the hospital discharge record from among all deliveries during 1987-2014 to examine maternal and infant outcomes, rehospitalization and mortality <2 years postpartum. Relative risks (RRs) and 95 % confidence intervals (CI) overall, and by epilepsy type were calculated using Poisson regression. We assessed the validity of epilepsy identification based on diagnosis codes by conducting a medical chart review for a sample of women.

RESULTS

Women with epilepsy had increased risks of preeclampsia (RR 1.23; 95 % CI 1.08-1.41) and gestational diabetes (RR 1.18; 95 % CI 1.02-1.36). Their infants had increased malformation (RR 1.23; 95 % C: 1.08-1.42) and small for gestational age (SGA, RR 1.39; 95 % CI 1.25-1.54) risks, and were nearly three times as likely to not be breastfed. Affected mothers (RR 5.25; 95 % CI 2.46-11.23) and their infants (RR 1.64, 95 % CI 1.41-1.89) required more ICU admissions during the delivery hospitalizations, and more postpartum rehospitalization, with greatest risk in the first six months. Maternal mortality < 2 years after delivery was increased (RR 7.11; 95 % CI 2.47-20.49). Increased risks were observed for all epilepsy subtypes for nearly all outcomes examined. Risks of preterm delivery and low birthweight increased over time (p <.05). Suggestive, but not statistically significant temporal decreases in risks of gestational diabetes and malformations and increased risk of preterm labor were noted. We observed high sensitivity of diagnosis codes for identifying pregnant women with epilepsy.

CONCLUSION

These population-based results emphasize the need for frequent postpartum monitoring of women with epilepsy. Increases in risks of low birthweight and preterm delivery over time are of concern. Possible temporal changes in other outcomes warrant further investigation.

Investigation on the Influencing Factors Related to Quality of Life of Adult Epilepsy Patients in Wenzhou, China, Based on Structural Equation Model

Objective. The aim of the study is to investigate the influencing factors of quality of life in adult patients with epilepsy in Wenzhou in China. Methods. A total of 190 patients who visited our hospital from July 2019 to February 2021 were included in the study. Demographic data and disease status were collected. Moreover, QOLIE-31, PSQI, ESS, HAMD-17, and GAD-7 were used in the questionnaire survey. Structural equation model fitting was used to analyze the influencing factors of quality of life in adult patients with epilepsy. Results. The scores of the dimension of onset worry in men were greater than those of women (P = 0.049), and the scores of the dimension of life satisfaction were lower than women (P = 0.047). The scores of cognitive function decreased with age (P = 0.047). The scores of quality of life of unemployed and drinking patients significantly decreased $\left(P<\mathit{0.05}\right)$ . The score of quality of life positively correlated with good economic status and family relations $\left(P<\mathit{0.05}\right)$ . The score of emotional health increased first and then decreased with the course of the disease. With the decrease in seizure frequency and the extension of months without a seizure, the score of quality of life gradually increased. Furthermore, the structural equation model showed that health status was directly correlated to the quality of life of patients with epilepsy. Conclusion. Male, unemployment, drinking, older age, and disease are negatively related to the quality of life in patients with epilepsy. However, good economic status, good family relations, and good colleague relationships are positively related to the quality of life.

Tardive Seizures After Electroconvulsive Therapy

OBJECTIVES

Seizures that occur spontaneously after termination of an electroconvulsive therapy (ECT) seizure are termed tardive seizures. They are thought to be a rare complication of ECT, influenced by risk factors that affect seizure threshold. However, there has been limited review of tardive seizures with modified ECT. We aimed to review the literature to provide clinical guidance for the use of ECT after tardive seizures.

METHODS

PubMed, EMBASE, PsycInfo, and CINAHL databases were searched from inception to May 2021 to identify cases of modified ECT, with evidence of a seizure occurring within 7 days of a terminated ECT seizure. Data for demographic, medical, pharmacological, anesthetic, and ECT variables as well as management strategies were collected.

RESULTS

There have been 39 episodes of modified ECT-related tardive seizures published over a period of 40 years. In 97.4% of cases, there was at least 1 identified potential risk factor for seizures, including use of a seizure-lowering medication and/or preexisting neurological injury. Major complications were uncommon (<15% of cases); however, 1 fetal death and 1 subsequent suicide were reported. No case was diagnosed with epilepsy, although around 20% continued on antiepileptic medications. More than half of the included patients were retrialed on ECT, with only 15% developing further tardive seizures.

CONCLUSIONS

Seizures that occurred spontaneously after the termination of an ECT seizure are a rare complication of modified ECT. Recommencing ECT after a tardive seizure may occur after review of modifiable seizure risk factors and with consideration of antiepileptic medication and extended post-ECT monitoring.

Alcohol, Coffee, and Milk Intake in Relation to Epilepsy Risk

Alcohol, coffee and milk intakes have been explored in relation to epilepsy risk in observational studies; however, the results were not consistent. We performed a Mendelian randomisation (MR) study to evaluate the causality of these relationships. Genetic variants associated with alcohol, coffee and milk intake were adopted as instrumental variables. We obtained the summary data of epilepsy from the International League Against Epilepsy (ILAE) Consortium (15,212 cases and 29,677 controls) and FinnGen consortium (4588 cases and 144,780 controls). Genetically predicted alcohol intake was associated with a higher risk of epilepsy in the ILAE Consortium (odds ratio (OR): 1.22, 95% confidence intervals (CI): 1.02-1.45). The association in the FinnGen consortium remained consistent in direction. Combined analysis of ILAE and FinnGen databases further indicated that genetically predicted alcohol intake was associated with a higher risk of epilepsy (OR = 1.24; 95% CI, 1.06-1.47, p = 0.009). Genetically predicted coffee intake was not related to epilepsy risk, while higher genetically predicted milk intake was related to a lower risk of epilepsy (OR = 0.957; 95% CI, 0.917-0.999, p = 0.044). Our results suggest a detrimental effect of alcohol intake on the risk of epilepsy, while milk intake might be associated with a decreased risk of epilepsy.

Current Cigarette Smoking Is Associated With a High Seizure Frequency and Anxiety Symptoms in People With Epilepsy

Purpose

This study aims to answer the following questions: how many people with epilepsy (PWE) have cigarette smoking habits? Which demographic or clinical characteristics are associated with cigarette smoking? Is cigarette smoking related to depressive and anxiety symptoms in PWE?

Methods

A total of 524 PWE were included in the final analysis. Demographic and clinical data were gathered and recorded. Smoking status was identified. The associations of smoking status with the clinical features of epilepsy and depressive and anxiety symptoms were evaluated by logistic regression models.

Results

The overall prevalence of cigarette smoking was 23.5% (123 PWE) in this sample. In the multivariate logistic regression model, men (adjusted OR = 10.414, 95% CI: 5.552–19.535, P &lt; 0.001), high seizure frequency (adjusted OR = 1.474, 95% CI: 1.043–2.084, P = 0.028), and anxiety symptoms (adjusted OR = 2.473, 95% CI: 1.483–4.112, P = 0.001) were shown to have independent associations with cigarette smoking in PWE.

Conclusion

Our findings suggested that the overall prevalence of cigarette smoking was 23.5% in adults with epilepsy, which is slightly lower than that (26.6%) in general adults in China. In the present study, cigarette smoking was associated with men, high seizure frequency, and anxiety symptoms in PWE. Further prospective clinical studies with larger sample sizes are required to confirm our findings.

Alcohol consumption on unprovoked seizure and epilepsy: An updated meta-analysis

BACKGROUND

Epilepsy is one of the most common neurological disorders, affecting approximately 50 million people worldwide. Although a positive association between alcohol consumption and epilepsy has been demonstrated in previous meta-analyses of case-control studies, the results of several recently published large cohort studies are contradictory. Therefore, we conducted an updated meta-analysis that included more recent data to clarify the association between alcohol consumption and epilepsy.

METHODS

The search was performed on 25 January 2021 using the Embase and MEDLINE databases. Cohort or case-control studies were eligible for inclusion in this study. We used restricted cubic spline analysis to perform a dose-response meta-analysis.

RESULTS

A total of eight studies, including three cohort and five case-control studies, were included in our meta-analysis. The pooled risk of epilepsy was 1.70 (1.16-2.49) in alcohol users compared to non-drinkers. Subgroup analysis of 50 g units showed that the epilepsy risk increased as alcohol intake increased. The pooled risk of cohort studies was 1.00 (0.65-1.54), and the pooled risk of case-control studies was 2.61 (1.29-5.29). According to the dose-response analysis, the regression coefficient was 1.009 (1.004-1.014), indicating a significant positive dose-response relationship.

CONCLUSION

Unlike the case-control studies, the cohort studies did not reveal a significant association between alcohol consumption and epilepsy. Further large cohort studies for the general population are required to assert a definite causal relationship between alcohol consumption and epilepsy and to identify a potential threshold.

Coffee consumption and seizure frequency in patients with drug-resistant focal epilepsy

OBJECTIVE

To assess the relation between coffee consumption and seizure frequency in patients with drug-resistant focal epilepsy.

METHODS

Cross-sectional analysis of data collected in the SAVE study, which included patients with drug-resistant focal epilepsy during long-term EEG monitoring. Patients in whom both coffee consumption and data about seizure frequency, including focal to bilateral tonic-clonic seizures (FBTCS), were available were selected. Coffee consumption was collected using a standardized self-report questionnaire and classified into four groups: none, rare (from less than 1 cup/week to up 3 cups/week), moderate (from 4 cups/week to 3 cups/day), and high (more than 4 cups/day).

RESULTS

Six hundred and nineteen patients were included. There was no relation between coffee consumption and total seizure frequency (p = 0.902). In contrast, the number of FBTCS reported over the past year was significantly associated with usual coffee consumption (p = 0.029). Specifically, number of FBCTS in patients who reported moderate coffee consumption was lower than in others. In comparison with patients with moderate coffee consumption, the odds ratio (95%CI) for reporting at least 1 FBTCS per year was 1.6 (1.03-2.49) in patients who never take coffee, 1.62 (1.02-2.57) in those with rare consumption and 2.05 (1.24-3.4) in those with high consumption. Multiple ordinal logistic regression showed a trend toward an association between coffee consumption and number of FBTCS (p = 0.08).

CONCLUSIONS AND RELEVANCE

Our data suggest that effect of coffee consumption on seizures might depend on dose with potential benefits on FBTCS frequency at moderate doses. These results will have to be confirmed by prospective studies.

Vascular risk factors as predictors of epilepsy in older age: The Framingham Heart Study

OBJECTIVE

Stroke is the most common cause of epilepsy in older age. Subclinical cerebrovascular disease is believed to underlie some of the 30%-50% of late-onset epilepsy without a known cause (Li et al. Epilepsia. 1997;38:1216; Cleary et al. Lancet. 2004;363:1184). We studied the role of modifiable vascular risk factors in predicting subsequent epilepsy among participants ages 45 or older in the Framingham Heart Study (FHS), a longitudinal, community-based study.

METHODS

Participants of the Offspring Cohort who attended FHS exam 5 (1991-1995) were included who were at least 45-years-old at that time, had available vascular risk factor data, and epilepsy follow-up (n = 2986, mean age 58, 48% male). Adjudication of epilepsy cases included review of medical charts to exclude seizure mimics and acute symptomatic seizures. The vascular risk factors studied included hypertension, diabetes mellitus, smoking, and hyperlipidemia. The role of the Framingham Stroke Risk Profile score was also investigated. Cox proportional hazards regression models were used for the analyses.

RESULTS

Fifty-five incident epilepsy cases were identified during a mean of 19 years of follow-up. Hypertension was associated with a near 2-fold risk (hazard ratio [HR]: 1.93, 95% confidence interval [CI]: 1.10-3.37, p = .022) of developing epilepsy, even after adjustment for prevalent and interim stroke. In secondary analysis, excluding patients with normal blood pressure who were receiving anti-HTN (anti-hypertensive) treatment (n = 2613, 50 incident epilepsy cases) the association was (HR: 2.44, 95% CI: 1.36-4.35, p = .003).

SIGNIFICANCE

Our results offer further evidence that hypertension, a potentially modifiable and highly prevalent vascular risk factor in the general population, increases 2- to 2.5-fold the risk of developing late-onset epilepsy.

Smoking and Neuropsychiatric Disease-Associations and Underlying Mechanisms

Despite extensive efforts to combat cigarette smoking/tobacco use, it still remains a leading cause of global morbidity and mortality, killing more than eight million people each year. While tobacco smoking is a major risk factor for non-communicable diseases related to the four main groups—cardiovascular disease, cancer, chronic lung disease, and diabetes—its impact on neuropsychiatric risk is rather elusive. The aim of this review article is to emphasize the importance of smoking as a potential risk factor for neuropsychiatric disease and to identify central pathophysiological mechanisms that may contribute to this relationship. There is strong evidence from epidemiological and experimental studies indicating that smoking may increase the risk of various neuropsychiatric diseases, such as dementia/cognitive decline, schizophrenia/psychosis, depression, anxiety disorder, and suicidal behavior induced by structural and functional alterations of the central nervous system, mainly centered on inflammatory and oxidative stress pathways. From a public health perspective, preventive measures and policies designed to counteract the global epidemic of smoking should necessarily include warnings and actions that address the risk of neuropsychiatric disease.

Modifiable risk factors for epilepsy: A two-sample Mendelian randomization study

INTRODUCTION

We conducted a two-sample Mendelian randomization study to determine the associations of modifiable risk factors with epilepsy.

METHODS

Fourteen potential risk factors for epilepsy were selected based on a systematic review of risk factors for epilepsy. Single-nucleotide polymorphisms associated with each exposure at the genome-wide significance threshold (p < 5×10^-8 ) were proposed as instrumental variables from corresponding genome-wide association studies. Summary-level data for epilepsy were obtained from the FinnGen consortium (4,588 cases and 144 780 noncases). Potential causal associations (p < .05) were attempted for replication using UK Biobank data (901 cases and 395 209 controls).

RESULTS

Among 14 potential risk factors, 4 showed significant associations with epilepsy in FinnGen. All associations were directionally similar in UK Biobank and associated with epilepsy at p ≤ .004 in meta-analyses of FinnGen and UK Biobank data. The odds ratios of epilepsy were 1.46 (95% CI, 1.18, 1.82) for one unit increase in log odds ratio of having depression, 1.44 (95% CI, 1.13, 1.85) for one standard deviation increase in serum ferritin, 1.12 (95% CI, 1.04, 1.21) for one standard deviation increase in transferrin saturation, and 1.25 (95% CI, 1.09, 1.43) for one standard deviation increase in the prevalence of smoking initiation. There were suggestive associations of serum iron and magnesium with epilepsy. No association was observed for insomnia, blood pressure, alcohol consumption, or serum vitamin B12, 25-hydroxyvitamin D and calcium levels.

CONCLUSION

This MR study identified several modifiable risk factors for adulthood epilepsy. Reducing prevalence of depression and smoking initiation should be considered as primary prevention strategies for epilepsy.

Nicotine: A Targeted Therapy for Epilepsy Due to nAChR Gene Variants

OBJECTIVE

Genetic variants of the neuronal nicotinic acetylcholine receptor (nAChR) cause autosomal dominant sleep-related hypermotor epilepsy. Approximately 30% of autosomal dominant sleep-related hypermotor epilepsy patients are medically intractable. In preclinical models, pathogenic nAChR variants cause a gain of function mutation with sensitivity to acetylcholine antagonists and agonists. Nicotine modifies the activity of nAChRs and can be used as targeted therapy.

METHODS

We reviewed next-generation sequencing epilepsy panels from a single laboratory (GeneDx) from patients at Children's Medical Center Dallas between 2011 and 2015 and identified patients with nAChR variants. Retrospective review of records included variant details, medical history, neuroimaging findings, and treatment history.

RESULTS

Twenty-one patients were identified. Four patients were prescribed nicotine patches for intractable seizures. Three of 4 patients had a clinical response, with >50% seizure reduction.

CONCLUSIONS

Treatment with a nicotine patch can be an effective therapy in epilepsy patients with nAChR gene variants. We propose consideration of transdermal nicotine treatment in intractable epilepsy with known nAChR variants as an experimental therapy. Further clinical trials are needed to fully define therapeutic effects.

Predictors of New-Onset Epilepsy in People With Younger-Onset Neurocognitive Disorders

Objective: People with neurocognitive disorders (NCDs) have an increased risk of epilepsy. However, most studies investigating the risk of seizures in people with NCDs are limited to those with Alzheimer's disease (AD) and vascular dementia (VD), and those who developed dementia after age 65 years. A knowledge gap exists regarding factors associated with development of epilepsy in people with younger-onset NCD, and those with non-AD and non-VD dementia subtypes. In this study, we aimed to identify the factors associated with the development of epilepsy in people with younger-onset NCDs of varied etiologies, the majority of whom had symptom onset prior to age 65 years. Participants and Methods: This was a retrospective study reviewing the medical records of consecutive people admitted with cognitive impairment to a tertiary neuropsychiatry unit between 1 January 2004 and 30 April 2019. People diagnosed with primary NCDs were included in the analysis. The prevalence and characteristics of epilepsy were described. The factors associated with developing epilepsy were identified in a binary logistic regression model. Results: A total of 427 people were included. One hundred fourteen had Alzheimer's disease, 104 frontotemporal dementia, 51 vascular dementia, 69 movement disorder-associated dementia, and 89 unspecified NCD. The median age on admission was 59 years (range 33-86) and 75.2% (n = 321/427) had young-onset NCD with onset before 65 years of age. 40/427 (9.4%) people had epilepsy, and epilepsy onset clustered between 2 years before and 6 years after the onset of cognitive decline in 80% (n = 32/40). The most frequent seizure type was focal to bilateral tonic-clonic seizure (35%, n = 14/40). Most of the people (94.7%, n = 36/38) achieved seizure freedom with one or two antiseizure medications. People with unspecified NCD (compared to frontotemporal dementia and movement disorder-associated dementia, age of onset of NCDs ≤50 years, and current smoking status were independently associated with higher risk of developing epilepsy. Conclusion: Epilepsy is common in people with younger-onset NCDs, and a high index of suspicion is warranted particularly for those with unspecified subtype and smoking status. Smoking reduction or cessation should be further investigated as a potentially modifiable factor for risk reduction.

Change in the Frequency of Seizure Attacks and Associated Factors Among Adult Epilepsy Patients at Amanuel Mental Specialized Hospital (AMSH): A Generalized Linear Mixed Model (GLMM)

BACKGROUND

While getting anti-epileptic drugs (AEDs) treatment around two-thirds of the patients with epilepsy enter a seizure-free state, but some of them continue to experience seizures which increase the risk of accident, disability, death, and treatment side effects. Therefore, this study aimed to identifychanges in the frequency of seizure attacks overtime and associated factors among adult patients with epilepsy.

METHODS

A retrospective two year follow-up study was conducted among adult patients with epilepsy who initiated AEDs between July 2017 and June 2019. A simple random sampling technique was applied to select 394 patient charts. The data were entered into Epi-data and then exported to R software for further analysis. A generalized linear mixed model under a negative binomial family was applied to identify determinants of the frequency of seizure attacks.

RESULTS

The median number of seizure attacks at baseline were 3 with the IQR of 2 and on average the frequency of seizure attacks decrease in a linear pattern over time. Age group 25-34 years (AIRR = 0.81 and 95% CI: 0.69-0.94), smoking (AIRR = 1.28 and 95% CI: 1.11-1.48), khat use (AIRR = 1.39 and 95% CI: 1.19-1.62), sleep deprivation (AIRR = 1.49 and 95% CI: 1.32-1.69), head injury (AIRR = 1.30 and 95% CI: 1.11-1.53), depression (AIRR = 1.39 and 95% CI: 1.17-1.65), treatment mode (AIRR= 1.22 and 95% CI: 1.07-1.39), and clumsiness (AIRR= 1.85 and 95% CI: 1.24-2.75) were statistically significant seizure predicting factors.

CONCLUSION

The number of seizure attack changes over time was decreased by a linear function that might reflect treatment effects of AEDs. Smokers, khat chewers, suffering a head injury, depression, experienced sleep deprivation, and clumsiness increases the number of seizure attacks. Conversely, the age group 25-34 years saw a decrease in the number of seizure attacks. This underscores that special attention should be given to substance users and those with related mental health disorders.

Expression profile of cytochrome P450s and effects of polycyclic aromatic hydrocarbons and antiepileptic drugs on CYP1 expression in MOG-G-CCM cells

AIMS

This study was performed to investigate the expression profile of cytochrome P450 (CYP) isoforms and effects of polycyclic aromatic hydrocarbons (PAHs) and antiepileptic drugs on CYP1 expression in human astrocytoma MOG-G-CCM cells.

MAIN METHODS

CYP1A1 and CYP1B1 expression were determined by quantitative real-time polymerase chain reaction, Western blotting, and immunocytochemistry.

KEY FINDINGS

MOG-G-CCM cells expressed various CYP isoforms. Among the CYP isoforms analyzed, CYP1B1 showed the highest expression level, followed by CYP1A1. Furthermore, CYP1B1 was localized in both the endoplasmic reticulum and mitochondria. 3-Methylcholanthrene (3-MC), benz[a]anthracene (B[a]A), benzo[a]pyrene (B[a]P), and valproic acid (VPA) increased the expression of CYP1B1 and CYP1A1. The potent aryl hydrocarbon receptor antagonist GNF351 significantly suppressed the 3-MC- and VPA-mediated upregulation of CYP1B1 and CYP1A1. In addition, VPA potentiated the induction of CYP1B1 and CYP1A1 by 3-MC, B[a]A, and B[a]P, although the augmentation of CYP1A1 was more remarkable than that of CYP1B1. In contrast, other antiepileptic drugs (carbamazepine, lamotrigine, levetiracetam, phenytoin) did not affect the 3-MC-mediated upregulation of CYP1B1 and CYP1A1. VPA is known to act as a histone deacetylase (HDAC) inhibitor. Therefore, the effects of trichostatin A, a representative HDAC inhibitor, on CYP1 induction by 3-MC were examined. Trichostatin A enhanced the 3-MC-mediated upregulation of CYP1A1 but not CYP1B1.

SIGNIFICANCE

These results partially indicated that VPA may augment the PAH-mediated induction of CYP1B1 and CYP1A1 through the activation of transcription by HDAC inhibition.

Identification of susceptibility variants to benign childhood epilepsy with centro-temporal spikes (BECTS) in Chinese Han population

BACKGROUND

Benign Childhood Epilepsy with Centro-temporal Spikes (BECTS) is the most common form of idiopathic epilepsy in children, accounting for up to 23% of pediatric epilepsy. The pathogenesis of BECTS is unknown, but it is thought that genetic factors play a role in susceptibility to the disease.

METHODS

To investigate the role of common genetic variants in BECTS pathogenesis, a 2-stage genome-wide association study (GWAS) was performed in 1,800 Chinese Han BECTS patients, and 7,090 healthy controls. Genetic findings were used in a Mendelian Randomization study in the UK Biobank dataset to investigate the potential role of smoking in BECTS.

FINDINGS

Definitive evidence of a role for common-variant heritability was demonstrated, with heritability of BECTS of >10% observed even with conservative disease prevalence assumptions. Although no individual locus achieved genome-wide significance, twelve loci achieved suggestive evidence of association (5 × 10^-8<P<10^-5). Using combined genetic and brain tissue gene expression data analyzed by Summary-data-based Mendelian Randomization (SMR), causative association of BECTS was demonstrated with SNP rs1948 and the CHRNA5 t3603436 transcript (P_eqtl = 2·10 × 10^-12, P_smr = 7·9 × 10^-5). This finding indicates rs1948 is significantly associated with BECTS through effects on expression of CHRNA5 in brain tissue. The identification of novel loci suggests involvements of KALRN and the CHRNA5-A3-B4 cluster in BECTS. Using a generalized SMR approach we demonstrate that maternal smoking around birth is significantly associated with increased risk of BECTS (odds ratio = 3·90, P = 0·0099).

INTERPRETATION

This study shows that BECTS risk is at least partially heritable and due to common genetic variants. Additionally, we demonstrate that BECTS risk is substantially increased by maternal smoking around birth.

Factors Associated with Good Seizure Control in Patients on Valproic Acid

Objective

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

Materials and Methods

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

Results

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

Conclusion

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

Seizure recurrence risk in persons with epilepsy undergoing antiepileptic drug tapering

OBJECTIVES

Antiepileptic drug (AED) tapering in persons with epilepsy (PWE) after 2-3 years of seizure freedom is still debatable because of the risk of seizure recurrence. Tapering patterns have wide variability and could impact seizure recurrence; this study aimed to find out the correlation between them.

MATERIAL AND METHODS

This prospective, observational independent assessor study enrolled PWE undergoing AED tapering in a tertiary care hospital. Data collected included demography, seizure history, AED treatment, and investigational findings. Tapering pattern was assessed based on seizure-free period and AED dose before onset of tapering, dose reduction percentage and frequency, duration of tapering, and follow-up. These variables were compared among the PWE with seizure recurrence and no seizure recurrence.

RESULTS

Among 408 enrolled PWE, 181 were on AED monotherapy: levetiracetam (73), valproate (45), carbamazepine (44), phenytoin (16), and clobazam (3). With a minimum 19 (maximum 41 months) follow-up, seizure recurrence was reported in 119 (29.2%) PWE. The seizure recurrence was not significantly different in-between mono and polytherapy groups; however, among monotherapy groups seizure recurrence was significantly higher (P = .023) in valproate (35.5%) followed by levetiracetam (28.8%) group. Parameters having significant association with seizure recurrence were duration of epilepsy (P = .03), frequency of seizures before control (P = .002), history of previously failed tapering (P = .04), and history of smoking/alcoholic/tobacco intake (P = .003).

CONCLUSIONS

There is a wide variation in AEDs tapering pattern and seizure recurrence risk can be minimized by considering the risk factors like history of smoking/alcoholic/tobacco, longer duration of epilepsy, frequency of seizures before control, and previously failed tapering.

Common mental disorders and its determinants among epileptic patients at an outpatient epileptic clinic in Felegehiwot Referral Hospital, Bahirdar, Ethiopia: cross-sectional study

Background

Epilepsy is a chronic neurological condition that is highly predisposed to a variety of mental health problems due to its huge biological, social and psychological burdens. Despite this, there is a paucity of research in this area. Therefore, assessing common mental disorders and its determinants among epileptic patients would be of great importance.

Objective

This study was aimed to asses prevalence and associated factors of common mental disorders among people with epilepsy attending Felegehiwot Referral Hospital, Bahirdar, Ethiopia, 2019.

Methods

Institutional based analytic cross-sectional study design was utilized from January to February 2019 at Felegehiwot Referral Hospital among 422 epileptic patients who were diagnosed clinically and on follow up treatment. Systematic random sampling was applied to recruit participants. Interviewer based and pretested Self Reporting Questionnaire‐20 was used to screen common mental illness with a cut-off point 7 and above as having a common mental disorder. Bivariate and multivariable logistic regression analysis with 95% CI were computed and variables with p < 0.05 in the final model were considered as associated factors for common mental disorders.

Result

Four hundred twenty-two patients with epilepsy were included in our study with a response rate of 100% and 64.5% were males. The mean age of participants was 59 ± 13.37 years. Common mental disorder among epileptic patients was found to be 35.8%. There was a statistically significant association between marital status, comorbid medical illness, nicotine dependence, alcohol misuse, and medication non-adherence with common mental disorders at p < 0.05.

Conclusion

The prevalence of common mental distress was high (35.8%) suggesting that it is a public health issue. Marital status, comorbid medical illness, nicotine dependence, alcohol misuse, and medication non-adherence were the factors having an association with a common mental disorder. Therefore, early screening and recognition of mental distress symptoms should be a routine activity while managing epileptic patients.

The Use of Caffeine by People with Epilepsy: the Myths and the Evidence

PURPOSE OF REVIEW

Caffeine is the most widely consumed central nervous stimulant. For people with epilepsy, it is often unclear whether drinking coffee carries a risk of triggering seizures.

RECENT FINDINGS

The relationship between caffeine, seizures, epilepsy, and anti-seizure drugs is not fully understood. Clinical studies are scarce. In animal models, caffeine can increase seizure susceptibility but can also protect from seizures. Effects seem dose-dependent and are influenced by the duration of intake and the developmental stage at which caffeine exposure started. Caffeine reduces the efficacy of several anti-seizure medications, especially topiramate. It is unclear how these findings, mainly from animal studies, can be translated to the clinical condition. At present, there is no evidence to advise people with epilepsy against the use or overuse of caffeine. Until clinical studies suggest otherwise, caffeine intake should be considered as a factor in achieving and maintaining seizure control in epilepsy.

The role of cigarette smoking in epilepsy severity and epilepsy-related quality of life

Empirical evidence suggests that cigarette smoking is common among individuals with epilepsy. However, little is known about relationship between smoking and clinical features of epilepsy. Thus, the aim of the current study was to examine the differences between smokers (n = 43; 58.1% female, M_age = 43.4 years, SD = 11.6) and nonsmokers (n = 49; 63.3% female, M_age = 48.5 years, SD = 15.9) with epilepsy in terms of epilepsy severity (i.e., presence of seizures in the past year, refractory epilepsy status) and epilepsy-related quality of life. As hypothesized, smokers with epilepsy, compared with nonsmokers with epilepsy, were at an increased risk to have experienced seizures in the past year after controlling for the effect of Medicaid status as a proxy for socioeconomic status (odds ratio [OR] = 3.61). Positive smoking status was also associated with lower levels of epilepsy-related quality of life; however, this finding did not remain significant when Medicaid status was taken into consideration. Contrary to the hypotheses, smokers with epilepsy were not at an increased risk of having refractory epilepsy compared with nonsmokers with epilepsy. These findings suggest that cigarette smoking is associated with at least one aspect of epilepsy severity. Thus, in addition to the broader health benefits, smokers with epilepsy should be advised of the increased seizure risk associated with current cigarette smoking. Future work should examine the longitudinal impact of smoking on epilepsy severity, including whether successful smoking cessation ameliorates the seizure risk found in this cross-sectional study.

Epilepsy and associated mortality in patients with multiple sclerosis

BACKGROUND AND PURPOSE

We aimed to determine the prevalence of epilepsy in patients with multiple sclerosis (MS) at diagnosis, the risk of developing epilepsy after the diagnosis of MS and the relative risk of mortality associated with epilepsy.

METHODS

We used the UK Clinical Practice Research Data-link to identify 2526 patients with incident MS and 9980 age-, sex- and index year-matched non-MS controls from 1997 to 2006. Logistic regression was used to estimate odds ratios [95% confidence interval (CI)] for epilepsy and Cox regression was used to estimate hazard ratios (HRs) (95% CI) for epilepsy and mortality.

RESULTS

Patients with incident MS were on average 45 years old and 70.9% were female. At diagnosis, the prevalence of epilepsy in patients with MS was 1.30% compared with 0.57% in non-MS controls. At diagnosis, MS was associated with an adjusted odds ratio (95% CI) of 2.11 (1.36-3.27) for pre-existing epilepsy. Among epilepsy-free patients, the cumulative probabilities of developing epilepsy, first recorded within 10 years of the index date, were 2.77% for patients with MS and 0.90% for controls. MS was associated with an adjusted HR (95% CI) of 6.01 (2.94-12.29) for epilepsy. Among patients with MS, epilepsy was associated with an HR (95% CI) of 2.23 (1.02-4.84) for all-cause mortality.

CONCLUSIONS

This population-based study found an increased prevalence of epilepsy in patients with MS at diagnosis when compared with non-MS controls and the risk of developing epilepsy was also higher following the MS diagnosis. Patients with MS with epilepsy had a higher risk of mortality compared with those without.

Alcohol Use and Alcohol-Related Seizures in Patients With Epilepsy

Purpose: This study aimed to assess alcohol consumption and the occurrence of alcohol-related seizures in patients with epilepsy within the last 12 months.

Methods: In an epilepsy outpatient clinic, a standardized questionnaire was used to collect data retrospectively from consecutive adult epilepsy patients who had been suffering from the disease for at least 1 year. Logistic regression analyses were performed to identify independent predictors.

Results: A total of 310 patients with epilepsy were included. Of these, 204 subjects (65.8%) consumed alcohol within the last 12 months. Independent predictors for alcohol use were antiepileptic drug monotherapy (OR 1.901) and physicians' advice that a light alcohol intake is harmless (OR 4.102). Seizure worsening related to alcohol consumption was reported by 37 of the 204 patients (18.1%) who had used alcohol. All 37 subjects had consumed large quantities of alcohol prior to the occurrence of alcohol-related seizures regardless of their usual alcohol-drinking behavior. The amount of alcohol intake prior to alcohol-related seizures was at least 7 standard drinks, which is equivalent to 1.4 L of beer or 0.7 L of wine. In 95% of cases, alcohol-related seizures occurred within 12 h after cessation of alcohol intake. Independent predictors for alcohol-related seizures were generalized genetic epilepsy (OR 5.792) and chronic heavier alcohol use (OR 8.955).

Conclusions: Two-thirds of interviewed subjects had consumed alcohol within the last 12 months. This finding may be an underestimate due to patients' self-reporting and recall error. In all cases, the occurrence of alcohol related-seizures was associated with timely consumption of considerably large amounts of alcohol. Thus, a responsible alcohol intake seems to be safe for most patients with epilepsy. However, subjects with epilepsy and especially those with generalized genetic epilepsy should be made aware of an increased risk for seizures related to heavy alcohol consumption. Factors accompanying acute heavy alcohol intake such as altered sleep architecture, impaired adherence to antiepileptic medication, and metabolic disturbances may further facilitate the occurrence of seizures.

Conditions Associated with Essential Tremor in Veterans: A Potential Role for Chronic Stress

Background

Increased depression, hearing loss, dementia, alcoholism, and mortality in essential tremor patients remain unexplained. We investigated whether conditions associated with tremor are linked to chronic stress.

Methods

The FY2013 Veterans Affairs database was queried for 38 selected dual diagnosis combinations in 5,854,223 veterans aged 21–95 years.

Results

Post-traumatic stress disorder, anxiety, and depression were the most common psychiatric diagnoses in tremor patients, with the odds ratio exceeding 2 in all 15-year cohorts. Depending on age, patients with essential tremor were more likely than those without to have obsessive–compulsive disorder, bipolar illness, schizophrenia, use tobacco and abuse alcohol, have hypertension, obesity, hyperlipidemia, diabetes, vitamin D deficiency, coronary and cerebrovascular diseases, congestive heart failure, stroke, asthma, hypothyroidism, irritable bowel syndrome, renal insufficiency, alcoholic liver disease, hearing loss, glaucoma, macular degeneration, migraine, epilepsy, idiopathic polyneuropathy, history of head trauma, and ‘Alzheimer’s dementia. In contrast, lung and colorectal cancer, amyotrophic lateral sclerosis, psychostimulant abuse, and rheumatoid arthritis were not more common.

Discussion

Post-traumatic stress disorder, anxiety, and depression, strongly associated with essential tremor, are known risk factors for poor health habits, tobacco use and alcohol abuse; collectively these are risk factors for vascular disease, with further negative health consequences for multiple organ systems. As essential tremor is associated with all these conditions, we propose that chronic stress is not only responsible for the conditions associated with tremor but in some cases itself directly and indirectly induces essential tremor, so that tremor and poor health share a common cause.

Amelioration of Pentylenetetrazole-Induced Seizures by Modulators of Sigma, N-Methyl-D-Aspartate, and Ryanodine Receptors in Mice

BACKGROUND

Sigma receptors, N-methyl-D-aspartate (NMDA) antagonist, and modulators of intracellular calcium may be useful for seizure control. Therefore, we aimed to evaluate the antiepileptic effects of opipramol, a sigma receptor agonist, against pentylenetetrazole (PTZ)-induced seizures in mice and assess ketamine and caffeine interaction with the antiepileptic effects of opipramol.

METHODS

PTZ (100 mg/kg) was used for the induction of seizure in 72 male albino Swiss strain of mice (n=8). Opipramole (10, 20, and 50 mg/kg), ketamine (50 mg/kg), caffeine (200 mg/kg), opipramole (20 mg/kg) plus ketamine (50 mg/kg), opipramole (20 mg/kg) plus caffeine (200 mg/kg), diazepam (5 mg/kg as a positive control), and the vehicle were administered interaperitoneally 30 minutes before the injection of PTZ. The latency was recorded for the clonic, tonic-clonic seizures, and death of animals after the injection of PTZ. Kruskal-Wallis test followed by Dunn's test was used for the analysis of data. Statistical analysis was performed with the SPSS software version 23.0 and P<0.05 was considered as the significant level.

RESULTS

Opipramol (20 mg/kg) increased the latency for the PTZ-induced clonic (44%, P=0.021) and tonic-clonic (130.80%, P=0.043) seizures compared with the vehicle-treated group. Animals treated with opipramol (20 mg/kg) plus caffeine (200 mg/kg) had a significantly higher onset of PTZ-induced clonic and tonic-clonic seizures compared with the control (P=0.046 and <0.001, respectively). Ketamine combined with opipramol increased the onset of tonic-clonic seizure compared with the vehicle-treated groups (P<0.001).

CONCLUSION

Opipramol attenuated the seizures induced by the PTZ. Ketamine and caffeine had no effect on the anticonvulsant activity of opipramol.

Caffeine Controls Glutamatergic Synaptic Transmission and Pyramidal Neuron Excitability in Human Neocortex

Caffeine is the most widely used psychoactive drug, bolstering attention and normalizing mood and cognition, all functions involving cerebral cortical circuits. Whereas studies in rodents showed that caffeine acts through the antagonism of inhibitory A₁ adenosine receptors (A₁R), neither the role of A₁R nor the impact of caffeine on human cortical neurons is known. We here provide the first characterization of the impact of realistic concentrations of caffeine experienced by moderate coffee drinkers (50 μM) on excitability of pyramidal neurons and excitatory synaptic transmission in the human temporal cortex. Moderate concentrations of caffeine disinhibited several of the inhibitory A₁R-mediated effects of adenosine, similar to previous observations in the rodent brain. Thus, caffeine restored the adenosine-induced decrease of both intrinsic membrane excitability and excitatory synaptic transmission in the human pyramidal neurons through antagonism of post-synaptic A₁R. Indeed, the A₁R-mediated effects of endogenous adenosine were more efficient to inhibit synaptic transmission than neuronal excitability. This was associated with a distinct affinity of caffeine for synaptic versus extra-synaptic human cortical A₁R, probably resulting from a different molecular organization of A₁R in human cortical synapses. These findings constitute the first neurophysiological description of the impact of caffeine on pyramidal neuron excitability and excitatory synaptic transmission in the human temporal cortex, providing adequate ground for the effects of caffeine on cognition in humans.

Smoking prevalence and seizure control in Chinese males with epilepsy

Smoking has a negative effect on most diseases, yet it is under-investigated in people with epilepsy; thus its role is not clear in the general population with epilepsy. We performed a retrospective pilot study on males with epilepsy to determine the smoking rate and its relationship with seizure control using univariate analysis to calculate odds ratios (ORs) and also used a multi-variate logistic regression model. The smoking rate in our sample of 278 individuals was 25.5%, which is lower than the general Chinese population smoking rate among males of 52.1%. We used two classifications: the first classified epilepsy as generalized, or by presumed topographic origin (temporal, frontal, parietal and occipital). The second classified the dominant seizure type of an individual as generalized tonic clonic seizure (GTCS), myoclonic seizure (MS), complex partial seizure (CPS), simple partial seizure (SPS), and secondary GTCS (sGTCS). The univariable analysis of satisfactory seizure control profile and smoking rate in both classifications showed a trend towards a beneficial effect of smoking although most were not statistically significant. Considering medication is an important confounding factor that would largely influence seizure control, we also conducted multi-variable analysis for both classifications with drug numbers and dosage. The result of our model also suggested that smoking is a protective factor. Our findings seem to suggest that smoking could have a potential role in seizure control although confounders need exploration particularly in view of the potential long term health effects. Replication in a much larger sample is needed as well as case control studies to elucidate this issue.

Key Findings on Alcohol Consumption and a Variety of Health Outcomes From the Nurses' Health Study

OBJECTIVES

To review critical contributions from the Nurses' Health Study (NHS) on alcohol consumption and health outcomes.

METHODS

We performed a narrative review of NHS (1980-2012) and NHS II (1989-2011) publications.

RESULTS

Using detailed information on self-reported alcohol drinking patterns obtained approximately every 4 years combined with extensive information on diet, lifestyle habits, and physician-diagnosed health conditions, NHS investigators have prospectively examined the risks and benefits associated with alcohol consumption. Moderate intake, defined as up to 1 drink a day, is associated with a lower risk of hypertension, myocardial infarction, stroke, sudden cardiac death, gallstones, cognitive decline, and all-cause mortality. However, even moderate intake places women at higher risk for breast cancer and bone fractures, and higher intake increases risk for colon polyps and colon cancer.

CONCLUSIONS

Regular alcohol intake has both risks and benefits. In analyses using repeated assessments of alcohol over time and deaths from all causes, women with low to moderate intake and regular frequency (> 3 days/week) had the lowest risk of mortality compared with abstainers and women who consumed substantially more than 1 drink per day.

Prevalence of Provocative Seizures in Persons with Epilepsy: A Longitudinal Study at Khon Kaen University Hospital, Thailand

Background and Objective. Provocative factors are one causative factor of seizure attacks in persons with epilepsy (PWE). There are limited data of prevalence and major provocative factors in Asian populations. Methods. This study was performed at the Epilepsy Clinic, Khon Kaen University Hospital. The patients who aged 15 years or over, who had been treated at least 3 months with at least one antiepileptic drug, and who were followed up for at least one year were included. Data of seizure control and triggers were collected retrospectively from medical records. Data analysis was performed to identify independent provocative factors. Results. A total of 382 PWE met the study criteria. The mean age was 40.4 ± 0.8 years. Approximately 44% of the patients had at least one provocative factor. By multivariate analysis, the independent provocative factors with the first three highest adjusted odds ratios were sleep deprivation (adjusted OR = 8.64, 95% CI 3.73–19.99), alcohol consumption (adjusted OR = 6.76, 95% CI 1.44–31.78), and feeling stressful (adjusted OR = 2.97, 95% CI 1.29–6.86). Conclusion. Almost half of seizure attacks may be caused by provocative factors in Thai PWEs and some factors may be preventable. Avoidance of these factors should be emphasized to epilepsy patients for improving clinical outcomes and quality of life.

Tobacco smoking, epilepsy, and seizures

Tobacco smoking is considered the greatest risk factor for death caused by noncommunicable diseases. In contrast to extensive research on the association between tobacco smoking and diseases such as heart attack, stroke, and cancers, studies on the association between tobacco smoking and seizures or epilepsy are insufficient. The exact roles tobacco smoking and nicotine use play in seizures or epilepsy have not been well reviewed. We reviewed available literature and found that 1) there are vast differences between tobacco smoke and nicotine based on their components and their effects on seizures or epilepsy; 2) the seizure risk in acute active tobacco smokers, women who smoke during pregnancy, electronic cigarette smokers, and the role of smoking in sudden unexplained/unexpected death in epilepsy remain unclear; 3) seizure risks are higher in acute secondhand smokers, chronic active smokers, and babies whose mothers smoke; 4) tobacco smoke protects against seizures in animal models whereas nicotine exerts mixed effects in animals; and 5) tobacco smoking agents can be noneffective, proconvulsant, or anticonvulsant. Finally, the opportunities for future research on this topic is discussed.

Nicotine decreases the activity of glutamate transporter type 3

Nicotine, the main ingredient of tobacco, elicits seizures in animal models and cigarette smoking is regarded as a behavioral risk factor associated with epilepsy or seizures. In the hippocampus, the origin of nicotine-induced seizures, most glutamate uptake could be performed primarily by excitatory amino acid transporter type 3 (EAAT3). An association between temporal lobe epilepsy and EAAT3 downregulation has been reported. Therefore, we hypothesized that nicotine may elicit seizures through the attenuation of EAAT3 activity. We investigated chronic nicotine exposure (72 h) cause reduction of the activity of EAAT3 in a Xenopus oocyte expression system using a two-electrode voltage clamp. The roles of protein kinase C (PKC) and phosphatidylinositol 3-kinase (PI3K) were also determined. Nicotine (0.001-1 μM) resulted in a time- and dose-dependent decrease in EAAT3 activity with maximal inhibition at nicotine concentrations of 0.03 μM or higher and at an exposure time of 72 h. Vmax on the glutamate response was significantly reduced in the nicotine group (0.03 μM for 72 h), but the Km value of EAAT3 for glutamate was not altered. When nicotine-exposed oocytes (0.03 μM for 72 h) were pretreated with phorbol-12-myristate-13-acetate (PMA, a PKC activator), the nicotine-induced reduction in EAAT3 activity was abolished. PKC inhibitors (staurosporine, chelerythrine, and calphostin C) significantly reduced basal EAAT3 activity, but there were no significant differences among the PKC inhibitors, nicotine, and PKC inhibitors+nicotine groups. Similar response patterns were observed among PI3K inhibitors (wortmannin and LY294002), nicotine, and PI3K inhibitors+nicotine. In conclusion, this study suggests that nicotine decreases EAAT3 activity, and that this inhibition seems to be dependent on PKC and PI3K. Our results may provide an additional mechanism for nicotine-induced seizure.

Is dietary caffeine involved in seizure precipitation?

Caffeine acts as a central nervous stimulant by blocking A1 and A2A adenosine receptors. Its effect on seizures is complex. Animal studies and case reports indicate that acute caffeine exposure may induce seizures, whereas chronic exposure might have an opposite effect. Patients acutely hospitalized for seizures (n = 174) were asked for their consumption of caffeinated beverages 24 h prior to admission as well as their habitual caffeine intake. Twenty-four-hour caffeine consumption was also recorded in a later telephone interview on a seizure-free day (n = 154). Thus, the patients served as their own controls. Categorized data were analyzed using the Wilcoxon's signed-ranks test. No difference was found between the intake of caffeine 24 h prior to the seizure and the habitual consumption (p = 0.37) or the consumption on a seizure-free day (p = 0.13). Thus, caffeine does not appear to be a common seizure precipitant.

Young adult ischaemic stroke related acute symptomatic and late seizures: risk factors

BACKGROUND AND PURPOSE

After first-ever ischaemic stroke, to assess the risk and baseline factors associated with acute symptomatic seizure (ASS) (occurring within 7 days) and late post-stroke seizure (LPS) (>7 days).

METHODS

All consecutive patients aged 15-49 with first-ever ischaemic stroke between 1994 and 2007 treated at the Helsinki University Central Hospital were included, using Cox proportional hazard models to identify factors associated with seizures. Adjustment was for age, gender, vascular risk factors, admission hyperglycemia (>6.1 mm) and hyponatremia (<137 mm), use of psychiatric medication, stroke severity (NIH Stroke Scale) and anatomical (Bamford criteria) and etiological (Trial of Org in Acute Stroke Treatment) stroke subtype.

RESULTS

ASSs emerged in 35 (3.5%) patients. LPSs (n = 102) occurred at a cumulative rate of 6.1% at 1 year, 9.5% at 5 years and 11.5% at 10 years. In multivariate analysis, anxiolytic use at time of index stroke (hazard ratio 13.43, 95% confidence interval 3.91-46.14), moderate stroke severity (3.95, 1.86-8.41), cortical involvement (3.69, 1.66-8.18) and hyponatremia (3.26, 1.41-7.57) were independently associated with ASSs. Risk factors for LPSs were total anterior circulation infarct (15.94, 7.62-33.33), partial anterior circulation infarct (3.48, 1.52-7.93), history of ASS (3.94, 2.07-7.48), antidepressant use at the time of LPS (3.88, 2.46-6.11), hemorrhagic infarct (1.94, 1.19-3.15), male gender (1.79, 1.10-2.92) and hyperglycemia (1.62, 1.05-2.51).

CONCLUSIONS

In young ischaemic stroke patients, the magnitude of seizure risk and the major risk factors were similar to older ischaemic stroke patients but risk factors for ASSs and LPSs differed.

[Convulsive crisis in Tramadol and caffeine abusers: about 8 cases and review of the literature]

Nous rapportons Huit cas de crises convulsives diagnostiquées comme maladie épileptique après ingestion de Tramadol et d'autres substances psychotropes dont la Caféine dans une région ou maladie épileptique et addiction au café sont fréquentes. L'objectif de ce travail était d'informer les praticiens sur le risque de convulsion lié à la consommation du Tramadol seul ou en association avec d'autres psychotropes en s'appuyant sur les données de la littérature. Il s'agissait d'une étude rétrospective et exhaustive de patients vus en consultation ambulatoire pour crise convulsive et consommation de Tramadol et de caféine de janvier à mai 2012. Les données collectées étaient les caractéristiques sociodémographiques et de la consommation de Tramadol. Le diagnostic de crise convulsive a été posé sur les renseignements obtenus à l'anamnèse. Tous les patients ont été soumis à un examen neurologique et aux critères de dépendance du Diagnostic and Statistical Manual of Mental Disorders (DSMIV)-R par rapport à leur consommation de Tramadol. Nous n'avons pas trouvé dans la littérature médicale de cas de consommation concomitante de Tramadol et de Caféine. Les données expérimentales suggèrent une action synergique du Tramadol et de la Caféine sur la douleur et le seuil épileptogène. Nos observations plaident également en faveur d'une synergie d'action de ces deux molécules dans la survenue des crises convulsives. La fréquence des crises convulsives suite à une intoxication par le Tramadol et la caféine est susceptible d'augmenter en Afrique en raison du mésusage croissant de ces substances. Une étude comparative usagers de Tramadol associé à la Caféine et usagers du Tramadol seul devrait permettre d’évaluer le risque.