Poststroke epilepsy: update and future directions

Exploratory study of blood biomarkers in patients with post-stroke epilepsy

INTRODUCTION

In addition to clinical factors, blood-based biomarkers can provide useful information on the risk of developing post-stroke epilepsy (PSE). Our aim was to identify serum biomarkers at stroke onset that could contribute to predicting patients at higher risk of PSE.

PATIENTS AND METHODS

From a previous study in which 895 acute stroke patients were followed-up, 51 patients developed PSE. We selected 15 patients with PSE and 15 controls without epilepsy. In a biomarker discovery setting, 5 Olink panels of 96 proteins each, were used to determine protein levels. Biomarkers that were down-regulated and overexpressed in PSE patients, and those that showed the strongest interactions with other proteins were validated using an enzyme-linked immunosorbent assay in samples from 50 PSE patients and 50 controls. A ROC curve analysis was used to evaluate the predictive ability of significant biomarkers to develop PSE.

RESULTS

Mean age of the PSE discovery cohort was 68.56 ± 15.1, 40% women and baseline NIHSS 12 [IQR 1-25]. Nine proteins were down-expressed: CASP-8, TNFSF-14, STAMBP, ENRAGE, EDA2R, SIRT2, TGF-alpha, OSM and CLEC1B. VEGFa, CD40 and CCL4 showed greatest interactions with the remaining proteins. In the validation analysis, TNFSF-14 was the single biomarker showing statistically significant downregulated levels in PSE patients (p = 0.006) and it showed a good predictive capability to develop PSE (AUC 0.733, 95% CI 0.601-0.865).

DISCUSSION AND CONCLUSION

Protein expression in PSE patients differs from that of non-epileptic stroke patients, suggesting the involvement of several different proteins in post-stroke epileptogenesis. TNFSF-14 emerges as a potential biomarker for predicting PSE.

Characteristics of Stroke-related Seizures and their Predictive Factors: A Tertiary Care Center Experience

BACKGROUND AND PURPOSE

Various risk factors have been described in the literature that increase the risk of seizures associated with stroke. This study was aimed to determine the occurrence rate of poststroke seizures (PSSs) and the associated risk factors in Arab population.

MATERIALS AND METHODS

Study included all stroke patients aged >18 years with a minimum follow-up of 24 months following stroke to identify seizure occurrence. Patient's hospital records for all admissions and clinic visits were reviewed. Seizures were classified into early PSS if they occur within 1 week of stroke, and late PSS if they occur after 1 week of stroke.

RESULTS

Out of 594 patients, 380 were males. Seizure occurrence was higher in anterior circulation infarctions (94.8%, P < 0.05), cortical location (80.5%, P < 0.05), large artery atherosclerosis (63.8%, P < 0.05), lower activated partial thromboplastin time (APTT) (P = 0.0007), patients with ischemic heart disease (IHD) (P = 0.01), and those who underwent craniotomy (P = 0.001). Nonhigh-density lipoprotein cholesterol was inversely related to PSS (P = 0.01). Higher stroke severity (89%) and confusion (67%) at the time of presentation were independently related to PSS.

CONCLUSIONS

Eighty-two (13.8%) patients had PSS. Greater stroke severity at presentation with altered sensorium was independent risk factors for the development of PSS. Patients with underlying IHD, lower APTT, and undergoing neurosurgical intervention require vigilant monitoring for PSS.

Late onset epilepsy and stroke: Diagnosis, pathogenesis and prevention

The association of stroke and late-onset epilepsy (LOE) is discussed with special regard to its diagnosis, pathogenesis, and prevention. In addition to epidemiological data, including those from different age groups, the mechanisms for the development of acute symptomatic and remote symptomatic seizures are reviewed. The risk factors associated with seizures and post-stroke epilepsy (PSE) are considered, along with the methodological limitations of the study. For future research, the distinction between acute and remote symptomatic seizure before or after seven days from stroke onset should be reviewed because different acute symptomatic seizures (ASSs) themselves can entail a variable PSE risk. The definition of LOE by age is hitherto inconsistent. Comparing adult lifespan epochs, it is evident that stroke and seizures exhibit similar prevalence profiles. Young adulthood, old adulthood, and elderly epochs may be relevant for the differentiation of LOE subtype by age, vascular comorbidity, and other characteristics. A step-scheme strategy as a possible contribution to cerebrovascular prevention approaches is proposed.

Clinical approaches for poststroke seizure: a review

Poststroke seizure is a potential complication of stroke, which is the most frequent acute symptomatic seizure in adults. Patients with stroke may present with an abnormal or aggressive behavior accompanied by altered mental status and symptoms, such as hemiparesis, dysarthria, and sensory deficits. Although stroke manifestations that mimic seizures are rare, diagnosing poststroke seizures can be challenging when accompanied with negative postictal symptoms. Differential diagnoses of poststroke seizures include movement disorders, syncope, and functional (nonepileptic) seizures, which may present with symptoms similar to seizures. Furthermore, it is important to determine whether poststroke seizures occur early or late. Seizures occurring within and after 7 d of stroke onset were classified as early and late seizures, respectively. Early seizures have the same clinical course as acute symptomatic seizures; they rarely recur or require long-term antiseizure medication. Conversely, late seizures are associated with a risk of recurrence similar to that of unprovoked seizures in a patient with a focal lesion, thereby requiring long-term administration of antiseizure medication. After diagnosis, concerns regarding treatment strategies, treatment duration, and administration of primary and secondary prophylaxis often arise. Antiseizure medication decisions for the initiation of short-term primary and long-term secondary seizure prophylaxis should be considered for patients with stroke. Antiseizure drugs such as lamotrigine, carbamazepine, lacosamide, levetiracetam, phenytoin, and valproate may be administered. Poststroke seizures should be diagnosed systematically through history with differential diagnosis; in addition, classifying them as early or late seizures can help to determine treatment strategies.

Risk Factors and Temporal Patterns of Poststroke Epilepsy across Stroke Subtypes: Insights from a Nationwide Cohort Study in Korea

INTRODUCTION

We aimed to investigate the risk factors associated with poststroke epilepsy (PSE) among patients with different subtypes of stroke, focusing on age-related risk and time-varying effects of stroke subtypes on PSE development.

METHODS

A retrospective, nationwide, population-based cohort study was conducted using Korean National Health Insurance Service-National Sample Cohort data. Patients hospitalized with newly diagnosed stroke from 2005 to 2015 were included and followed up for up to 10 years. The primary outcome was the development of PSE, defined as having a diagnostic code and a prescription for anti-seizure medication. Multivariable Cox proportional hazard models were used to estimate PSE hazard ratios (HRs), and time-varying effects were also assessed.

RESULTS

A total of 8,305 patients with ischemic stroke, 1,563 with intracerebral hemorrhage (ICH), and 931 with subarachnoid hemorrhage (SAH) were included. During 10 years of follow-up, 4.6% of patients developed PSE. Among patients with ischemic stroke, significant risk factors for PSE were younger age (HR = 1.47), living in rural areas (HR = 1.35), admission through the emergency room (HR = 1.33), and longer duration of hospital stay (HR = 1.45). Time-varying analysis revealed elevated HRs for ICH and SAH, particularly in the first 2 years following the stroke. The age-specific HRs also showed an increased risk for those under the age of 65, with a noticeable decrease in risk beyond that age.

CONCLUSION

The risk of developing PSE varies according to stroke subtype, age, and other demographic factors. These findings underscore the importance of tailored poststroke monitoring and management strategies to mitigate the risk of PSE.

Clinical Implications of Various Electroencephalographic Patterns in Post-Stroke Seizures. The Utility of Routine Electroencephalogram

Objective: Post-stroke seizures (PSS) are one of the major stroke-related complications. Early therapeutic interventions are critical therefore using electroencephalography (EEG) as a predictive tool for future recurrence may be helpful. We aimed to assess frequencies of different EEG patterns in patients with PSS and their association with seizure recurrence and functional outcomes. Methods: All patients admitted with PSS were included and underwent interictal EEG recording during their admission and monitored for seizure recurrence for 24 months. Results: PSS was reported in 106 patients. Generalized slow wave activity (GSWA) was the most frequent EEG pattern observed (n  =  62, 58.5%), followed by Focal sharp wave discharges (FSWDs) (n  =  57, 55.8%), focal slow wave activity (FSWA) (n  =  56, 52.8%), periodic discharges (PDs) (n  =  13, 12.3%), and ictal epileptiform abnormalities (n  =  6, 5.7%). FSWA and ictal EAs were positively associated with seizure recurrence (p < .001 and p  =  .015 respectively) and it remained significant even after adjusting for age, sex, stroke severity, stroke subtype, or use of anti-seizure medications (ASMs). Other positive associations were status epilepticus (SE) (p  =  .015), and use of older ASM (p < .001). FSWA and GSWA in EEG were positively associated with severe functional disability (p  =  .055, p  =  .015 respectively). Other associations were; Diabetes Mellitus (p  =  .034), Chronic Kidney Disease (p  =  .002), use of older ASMs (p  =  .037), presence of late PSS (p  =  .021), and those with Ischemic stroke (p  =  .010). Conclusions: Recognition and documentation of PSS-related EEG characteristics are important, as certain EEG patterns may help to identify the patients who are at risk of developing recurrence or worse functional outcomes.

The added value of risk assessment and subsequent targeted treatment for epileptic seizures after stroke: An early-HTA analysis

INTRODUCTION

The development of post-stroke epilepsy (PSE) is related to a worse clinical outcome in stroke patients. Adding a biomarker to the clinical diagnostic process for the prediction of PSE may help to establish targeted and personalized treatment for high-risk patients, which could lead to improved patient outcomes. We assessed the added value of a risk assessment and subsequent targeted treatment by conducting an early Health Technology Assessment.

METHODS

Interviews were conducted with four relevant stakeholders in the field of PSE to obtain a realistic view of the current healthcare and their opinions on the potential value of a PSE risk assessment and subsequent targeted treatment. The consequences on quality of life and costs of current care of a hypothetical care pathway with perfect risk assessment were modeled based on information from a literature review and the input from the stakeholders. Subsequently, the maximum added value (the headroom) was calculated. Sensitivity analyses were performed to test the robustness of this result to variation in assumed input parameters, i.e. the accuracy of the risk assessment, the efficacy of anti-seizure medication (ASM), and the probability of patients expected to develop PSE.

RESULTS

All stakeholders considered the addition of a predictive biomarker for the risk assessment of PSE to be of value. The headroom amounted to €12,983. The sensitivity analyses demonstrated that the headroom remained beneficial when varying the accuracy of the risk assessment, the ASM efficacy, and the number of patients expected to develop PSE.

DISCUSSION

We showed that a risk assessment for PSE development is potentially valuable. This work demonstrates that it is worthwhile to undertake clinical studies to evaluate biomarkers for the prediction of patients at high risk for PSE and to assess the value of targeted prophylactic treatment.

Common Pathways of Epileptogenesis in Patients With Epilepsy Post-Brain Injury: Findings From a Systematic Review and Meta-analysis

BACKGROUND AND OBJECTIVES

Epilepsy may result from various brain injuries, including stroke (ischemic and hemorrhagic), traumatic brain injury, and infections. Identifying shared common biological pathways and biomarkers of the epileptogenic process initiated by the different injuries may lead to novel targets for preventing the development of epilepsy. We systematically reviewed biofluid biomarkers to test their association with the risk of post-brain injury epilepsy.

METHODS

We searched articles until January 25, 2022, in MEDLINE, Embase, PsycInfo, Web of Science, and Cochrane. The primary outcome was the difference in mean biomarker levels in patients with and without post-brain injury epilepsy. We used the modified quality score on prognostic studies for risk of bias assessment. We calculated each biomarker's pooled standardized mean difference (SMD) and 95% CI. Molecular interaction network and enrichment analyses were conducted in Cytoscape (PROSPERO CRD42021297110).

RESULTS

We included 22 studies with 1,499 cases with post-brain injury epilepsy and 7,929 controls without post-brain injury epilepsy. Forty-five biomarkers in the blood or CSF were investigated with samples collected at disparate time points. Of 22 studies, 21 had a moderate-to-high risk of bias. Most of the biomarkers (28/45) were investigated in single studies; only 9 provided validation data, and studies used variable definitions for early-onset and late-onset seizures. A meta-analysis was possible for 19 biomarkers. Blood glucose levels in 4 studies were significantly higher in patients with poststroke epilepsy (PSE) than those without PSE (SMD 0.44; CI 0.19-0.69). From individual studies, 15 biomarkers in the blood and 7 in the CSF were significantly associated with post-brain injury epilepsy. Enrichment analysis identified that the significant biomarkers (interleukin [IL]-6, IL-1β]) were predominantly inflammation related.

DISCUSSION

We cannot yet recommend using the reported biomarkers for designing antiepileptogenesis trials or use in the clinical setting because of methodological heterogeneity, bias in the included studies, and insufficient validation studies. Although our analyses indicate the plausible role of inflammation in epileptogenesis, this is likely not the only mechanism. For example, an individual's genetic susceptibilities might contribute to his/her risk of epileptogenesis after brain injury. Rigorously designed biomarker studies with methods acceptable to the regulatory bodies should be conducted.

The Primary Prevention of Poststroke Epilepsy in Patients With Middle Cerebral Artery Infarct: Protocol for a Randomized Controlled Trial

BACKGROUND

Poststroke epilepsy poses a significant clinical challenge for individuals recovering from strokes, leading to a less favorable long-term outlook and increased mortality rates. Existing studies have primarily concentrated on administering antiseizure or anticonvulsant treatments only after the onset of late-onset seizures, without intervening during the epileptogenesis phase following a stroke.

OBJECTIVE

This research protocol is designed to conduct a randomized controlled trial to assess whether the early, preventive introduction of low-dose antiepileptic drug therapy (levetiracetam [LEV] or perampanel [PER]) in patients who have experienced middle cerebral artery (MCA) infarction can reduce the risk of developing poststroke epilepsy (primary prevention).

METHODS

Participants with MCA infarction, either with or without reperfusion treatments, will be recruited and promptly receive preventive intervention within 72 hours of the stroke occurrence. These participants will be randomly assigned to receive either PER (4 mg per day), LEV (1000 mg per day), or a placebo that matches the active drugs. This treatment will continue for 12 weeks after allocation. Brain magnetic resonance imaging will be used to confirm the presence of MCA territory infarction, and an electroencephalography will be used to ensure the absence of epileptiform discharges or electrographic seizures at the time of the stroke. All participants will undergo follow-up assessments for 72 weeks after allocation.

RESULTS

The primary outcome under evaluation will be the incidence of poststroke epilepsy in the 3 groups following the 18-month study period. Secondary outcomes will encompass the time to the occurrence of the first seizure, the severity of seizures, any treatment-related adverse events, and the modified Rankin scale score at 3 and 18 months. Exploratory outcomes will involve comparing the effectiveness and safety of PER and LEV.

CONCLUSIONS

We anticipate that the intervention groups will experience a lower incidence and reduced severity of poststroke epilepsy compared to the control group after 18 months. We aim to establish evidence supporting the potential preventive effects of LEV and PER on poststroke seizures and epilepsy in patients with MCA infarction, as well as to explore the antiepileptogenic potential of both LEV and PER in patients with major ischemic strokes.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04858841; https://clinicaltrials.gov/study/NCT04858841.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/49412.

Clinical characteristics and outcomes of patients with post-stroke epilepsy: protocol for an individual patient data meta-analysis from the International Post-stroke Epilepsy Research Repository (IPSERR)

INTRODUCTION

Despite significant advances in managing acute stroke and reducing stroke mortality, preventing complications like post-stroke epilepsy (PSE) has seen limited progress. PSE research has been scattered worldwide with varying methodologies and data reporting. To address this, we established the International Post-stroke Epilepsy Research Consortium (IPSERC) to integrate global PSE research efforts. This protocol outlines an individual patient data meta-analysis (IPD-MA) to determine outcomes in patients with post-stroke seizures (PSS) and develop/validate PSE prediction models, comparing them with existing models. This protocol informs about creating the International Post-stroke Epilepsy Research Repository (IPSERR) to support future collaborative research.

METHODS AND ANALYSIS

We utilised a comprehensive search strategy and searched MEDLINE, Embase, PsycInfo, Cochrane, and Web of Science databases until 30 January 2023. We extracted observational studies of stroke patients aged ≥18 years, presenting early or late PSS with data on patient outcome measures, and conducted the risk of bias assessment. We did not apply any restriction based on the date or language of publication. We will invite these study authors and the IPSERC collaborators to contribute IPD to IPSERR. We will review the IPD lodged within IPSERR to identify patients who developed epileptic seizures and those who did not. We will merge the IPD files of individual data and standardise the variables where possible for consistency. We will conduct an IPD-MA to estimate the prognostic value of clinical characteristics in predicting PSE.

ETHICS AND DISSEMINATION

Ethics approval is not required for this study. The results will be published in peer-reviewed journals. This study will contribute to IPSERR, which will be available to researchers for future PSE research projects. It will also serve as a platform to anchor future clinical trials.

TRIAL REGISTRATION NUMBER

NCT06108102.

Incidence and risk factors of post-stroke seizures and epilepsy: systematic review and meta-analysis

OBJECTIVE

Due to variability in reports, the aim of this meta-analysis was to evaluate the incidence and risk factors of post-stroke early seizures (ES) and post-stroke epilepsy (PSE).

METHODS

The MEDLINE, EMBASE and Web of Science databases were searched for post-stroke ES/PSE articles published on any date up to November 2020. Post-stroke ES included seizures occurring within 7 days of stroke, and PSE included at least one unprovoked seizure. Using random effects models, the incidence and risk factors of post-stroke ES and PSE were evaluated. The study was retrospectively registered with INPLASY (INPLASY2023100008).

RESULTS

Of 128 included studies in total, the incidence of post-stroke ES was 0.07 (95% confidence interval [CI] 0.05, 0.10) and PSE was 0.10 (95% CI 0.08, 0.13). The rates were higher in children than adults. Risk factors for post-stroke ES included hemorrhagic stroke (odds ratio [OR] 2.14, 95% CI 1.44, 3.18), severe strokes (OR 2.68, 95% CI 1.73, 4.14), cortical involvement (OR 3.09, 95% CI 2.11, 4.51) and hemorrhagic transformation (OR 2.70, 95% CI 1.58, 4.60). Risk factors for PSE included severe strokes (OR 4.92, 95% CI 3.43, 7.06), cortical involvement (OR 3.20, 95% CI 2.13, 4.81), anterior circulation infarcts (OR 3.28, 95% CI 1.34, 8.03), hemorrhagic transformation (OR 2.81, 95% CI 1.25, 6.30) and post-stroke ES (OR 7.24, 95% CI 3.73, 14.06).

CONCLUSION

Understanding the risk factors of post-stroke ES/PSE may identify high-risk individuals who might benefit from prophylactic treatment.

Clinical risk factors related to post-stroke epilepsy patients in Indonesia: a hospital-based study

Background

Stroke had been accounted to cause almost 50% of epilepsy in the elderly and may lead to poor functional outcomes. Many studies examining the risk factors have been conducted despite showing inconsistent results and currently still difficult to predict the occurrence of post-stroke epilepsy. The study aimed to determine risk factors related to post-stroke epilepsy that influence clinical seizure, electroencephalography (EEG), and functional outcome of patients. Analytic retrospective case–control study was conducted with a total sampling of 62 samples of post-stroke epilepsy and 62 samples of control from all stroke patients in the Neurology Clinic from January 2019 to December 2021. Epilepsy was classified according to the criteria of the International League Against Epilepsy (ILAE) in 2017. The relevant demographic and clinical data were collected.

Result

The study involved 62 patients in the case group (average age of onset = 57.69; 42 men, 20 women; 51 ischemic stroke, 11 hemorrhagic stroke) and 62 patients in the control group (average age of onset = 56.90; 24 men, 38 women; 52 ischemic stroke, 10 hemorrhagic stroke). We found that 31 patients had focal-to-bilateral seizures, 26 patients had generalized seizures and 5 patients had focal seizures. Men (p = 0.001; OR 3.325) and NIHSS Score (p = 0.027; OR 5.094) had significant correlations with post-stroke epilepsy. Ischemic stroke had a significant correlation (p = 0.008) with seizure onset. Women also had a significant correlation (p = 0.012) with EEG abnormalities. The study found that 59 of 62 post-stroke epilepsy patients had poor functional outcomes (mRS > 2).

Conclusion

Our study confirmed that most patients had focal-to-bilateral seizure patterns that occurred in 1–2 years after stroke, and had poor functional outcomes. Men had 3.325 times more likely to develop post-stroke epilepsy than women. Also, NIHSS score ≥ 15 correlated and 5.094 times more likely to develop post-stroke epilepsy. Ischemic stroke had a peak of epilepsy onset at 1–2 years after stroke and women had significant showing abnormalities on EEG recording than men.

Comparative Effectiveness and Safety of Seizure Prophylaxis Among Adults After Acute Ischemic Stroke

BACKGROUND

Older adults occasionally receive seizure prophylaxis in an acute ischemic stroke (AIS) setting, despite safety concerns. There are no trial data available about the net impact of early seizure prophylaxis on post-AIS survival.

METHODS

Using a stroke registry (American Heart Association's Get With The Guidelines) individually linked to electronic health records, we examined the effect of initiating seizure prophylaxis (ie, epilepsy-specific antiseizure drugs) within 7 days of an AIS admission versus not initiating in patients ≥65 years admitted for a new, nonsevere AIS (National Institutes of Health Stroke Severity score ≤20) between 2014 and 2021 with no recorded use of epilepsy-specific antiseizure drugs in the previous 3 months. We addressed confounding by using inverse-probability weights. We performed standardization accounting for pertinent clinical and health care factors (eg, National Institutes of Health Stroke Severity scale, prescription counts, seizure-like events).

RESULTS

The study sample included 151 patients who received antiseizure drugs and 3020 who did not. The crude 30-day mortality risks were 219 deaths per 1000 patients among epilepsy-specific antiseizure drugs initiators and 120 deaths per 1000 among noninitiators. After standardization, the estimated mortality was 251 (95% CI, 190-307) deaths per 1000 among initiators and 120 (95% CI, 86-144) deaths per 1000 among noninitiators, corresponding to a risk difference of 131 (95% CI, 65-200) excess deaths per 1000 patients. In the prespecified subgroup analyses, the risk difference was 52 (95% CI, 11-72) among patients with minor AIS and 138 (95% CI, 52-222) among moderate-to-severe AIS patients. Similarly, the risk differences were 86 (95% CI, 18-118) and 157 (95% CI, 57-219) among patients aged 65 to 74 years and ≥75 years, respectively.

CONCLUSIONS

There was a higher risk of 30-day mortality associated with initiating versus not initiating seizure prophylaxis within 7 days post-AIS. This study does not support the role of seizure prophylaxis in reducing 30-day poststroke mortality.

Diagnosis and Treatment of Poststroke Epilepsy: Where Do We Stand?

Purpose of Review

Stroke is the most common cause of seizures and epilepsy in older adults. This educational paper aims to give an update on current clinical aspects of diagnosis and treatment of poststroke epilepsy.

Recent Findings

Regarding epileptic seizures related to stroke, it is important to distinguish between acute symptomatic seizures and unprovoked seizures as they differ in their risk for seizure recurrence. In fact, after a single unprovoked poststroke seizure, a diagnosis of epilepsy can be made because there is a greater than 60% risk for further seizures. Clinical models that can predict the development of epilepsy after a stroke have been successfully established. However, treatment with anti-seizure medications is advised only after a first unprovoked poststroke seizure, as current treatments are not known to be effective for primary prevention. The management of poststroke epilepsy requires consideration of aspects such as age, drug-drug interactions and secondary vascular prophylaxis, yet evidence for the use of anti-seizure medications specifically in poststroke epilepsy is limited.

Summary

This text reviews the epidemiology and risk factors for poststroke epilepsy, explains the role of EEG and neuroimaging in patients with stroke and seizures and provides an overview on the clinical management of stroke-related acute symptomatic seizures and poststroke epilepsy.

Post-stroke epilepsy and risk of all-cause mortality: A systematic review and meta-analysis of cohort studies

OBJECTIVE

Post-stroke epilepsy (PSE) has been suggested as a predictor of poor prognosis. We aimed to evaluate the association between PSE and all-cause mortality via a meta-analysis.

METHODS

Relevant cohort studies were identified by search of electronic databases including PubMed, Embase, and Web of Science. Two authors independently performed database search, data collection, and study quality evaluation. A randomized-effect model incorporating the possible between-study heterogeneity was used to pool the results.

RESULTS

Overall, ten cohort studies including 177,929 patients with stroke contributed to the meta-analysis. Of them, 15,836 (8.9%) had PSE during a mean follow-up of 4 years. Compared to stroke survivors without PSE, patients with PSE had a significantly increased risk of all-cause death (odds ratio [OR]: 1.68, 95% confidence interval: 1.51-1.87, p < 0.001; I² = 80%). Subgroup analyses showed consistent association in patients with ischemic and hemorrhagic stroke, in prospective and retrospective studies, in PSE diagnosed as unprovoked seizure occurred more than 7 days and 14 days after stroke, in studies with follow-up durations within or over 5 years, and in studies with different quality scores (p for subgroup effect all < 0.05). The Galbraith plot identified three outlier studies which may contribute to the heterogeneity of the meta-analysis, and all of the three studies were database-linked studies. The between-study heterogeneity was significantly reduced after removing the three database-linked studies (OR: 1.39, 95% CI: 1.18-1.62, p < 0.001; I² = 0%).

CONCLUSION

PSE was associated with a higher risk of all-cause mortality.

Incidence and Antiseizure Medications of Post-stroke Epilepsy in Umbria: A Population-Based Study Using Healthcare Administrative Databases

Introduction: Post-stroke epilepsy (PSE) requires long-term treatment with antiseizure medications (ASMs). However, epidemiology of PSE and long-term compliance with ASM in this population are still unclear. Here we report, through population-level healthcare administrative data, incidence, risk factors, ASM choice, and ASM switch over long-term follow-up. Materials and Methods: This is a population-based retrospective study using Umbria healthcare administrative database. Population consisted of all patients with acute stroke, either ischaemic or hemorrhagic, between 2013 and 2018. ICD-9-CM codes were implemented to identify people with stroke, while PSE was adjudicated according to previously validated algorithm, such as EEG and ≥1 ASM 7 days after stroke. Results: Overall, among 11,093 incident cases of acute stroke (75.9% ischemic), 275 subjects presented PSE, for a cumulative incidence of 2.5%. Patients with PSE were younger (64 vs. 76 years), more frequently presented with hemorrhagic stroke, and had longer hospital stay (15.5 vs. 11.2 days) compared with patients without PSE. Multivariable Cox proportional hazards models confirmed that PSE associated with hemorrhagic stroke, younger age, and longer duration of hospital stay. Levetiracetam was the most prescribed ASM (55.3%), followed by valproate and oxcarbazepine. Almost 30% of patients prescribed with these ASMs switched treatment during follow-up, mostly toward non-enzyme-inducing ASMs. About 12% of patients was prescribed ASM polytherapy over follow-up. Conclusions: Post-stroke epilepsy is associated with hemorrhagic stroke, younger age, and longer hospital stay. First ASM is switched every one in three patients, suggesting the need for treatment tailoring in line with secondary prevention.

Seizures and epilepsy in patients with ischaemic stroke

BACKGROUND

With the increased efficacy of stroke treatments, diagnosis and specific treatment needs of patients with post-stroke seizures (PSS) and post-stroke epilepsy have become increasingly important. PSS can complicate the diagnosis of a stroke and the treatment of stroke patients, and can worsen post-stroke morbidity. This narrative review considers current treatment guidelines, the specifics of antiseizure treatment in stroke patients as well as the state-of-the-art in clinical and imaging research of post-stroke epilepsy. Treatment of PSS needs to consider indications for antiseizure medication treatment as well as individual clinical and social factors. Furthermore, potential interactions between stroke and antiseizure treatments must be carefully considered. The relationship between acute recanalizing stroke therapy (intravenous thrombolysis and mechanical thrombectomy) and the emergence of PSS is currently the subject of an intensive discussion. In the subacute and chronic post-stroke phases, important specific interactions between necessary antiseizure and stroke treatments (anticoagulation, cardiac medication) need to be considered. Among all forms of prevention, primary prevention is currently the most intensively researched. This includes specifically the repurposing of drugs that were not originally developed for antiseizure properties, such as statins. PSS are presently the subject of extensive basic clinical research. Of specific interest are the role of post-stroke excitotoxicity and blood-brain barrier disruption for the emergence of PSS in the acute symptomatic as well as late (> 1 week after the stroke) periods. Current magnetic resonance imaging research focussing on glutamate excitotoxicity as well as diffusion-based estimation of blood-brain barrier integrity aim to elucidate the pathophysiology of seizures after stroke and the principles of epileptogenesis in structural epilepsy in general. These approaches may also reveal new imaging-based biomarkers for prediction of PSS and post-stroke epilepsy.

CONCLUSION

PSS require the performance of individual risk assessments, accounting for the potential effectiveness and side effects of antiseizure therapy. The use of intravenous thrombolysis and mechanical thrombectomy is not associated with an increased risk of PSS. Advances in stroke imaging may reveal biomarkers for PSS.

Childhood strokes in China describing clinical characteristics, risk factors and performance indicators: a case-series study

AIM

To investigate clinical characteristics, risk factors (RFs), neurologic deficits and medical care provided in children who had a stroke in China.

METHODS

We conducted a retrospective case-series study using the medical records of children aged 1 month to 18 years with arterial ischaemic stroke (AIS) or haemorrhagic stroke (HS) (with the entry codes I60, I61, I62, I63 (ICD-10)), who were admitted to different hospitals in Beijing, between January 2018 and December 2018. We obtained the following information from the charts: demographic characteristics, clinical presentations, RFs for paediatric stroke, laboratory examination, neuroimaging records and neurologic sequelae.

RESULTS

We identified 312 first admissions for stroke (172 AIS and 140 HS). The mean age at onset was 8.6±3.9 years for patients who had an AIS and 8 (5-13) years for patients who had an HS. There were more males than females in both groups (AIS: 59.88% vs 40.12%; HS: 52.14% vs 47.86%). A known aetiology was identified in 92.44% and 86.43% of patients who had an AIS and HS, respectively. The leading cause of AIS was cerebrovascular diseases including moyamoya (68.6%), while that for HS was arteriovenous malformation (51.43%). The most common initial clinical presentation was hemiplegia (86.05%) in patients who had an AIS and headache (67.86%) in patients who had an HS. The use of healthcare, including acute treatment (antithrombotic in 17.44%, anticoagulant in 5.23%) and secondary prevention (antithrombotic in 6.39%, anticoagulant in 1.16%), varied and was significantly lower among patients who had an AIS. The most common complications were epilepsy (22.09%) and pneumonia (4.65%) in patients who had an AIS and epilepsy (17.14%) and hydrocephalus (12.14%) in patients who had an HS. Neurological deficits occurred in 62.8% of patients who had an AIS and 72.86% of patients who had an HS.

CONCLUSION

Cerebral arteriopathy was a major RF for both AIS and HS in children living in China. Large epidemiological studies are required to identify RFs to prevent stroke as well as appropriate interventions.

Early Post-Stroke Seizures in Acute Ischemic Stroke: A Prospective Cohort Study

Introduction

Stroke is the most common cause of epilepsy in the adult population. Post-stroke seizures (PSSs) are classified into early-onset seizures (ES) and late-onset (LS). ES can significantly affect the clinical outcome and occurrence of LS.

Methods

We analyzed data from a prospective cohort of acute ischemic stroke patients between June 2018 and May 2020 in a neurology unit at a tertiary hospital. We screened all acute stroke patients and included consecutive patients older than 18 years of age, presenting with acute, first-ever neuroimaging-confirmed ischemic stroke. We excluded patients with a previous stroke, transient ischemic attacks, hemorrhagic stroke, cerebral venous thrombosis, prior history of seizures, or any other epileptogenic comorbidity. ES were classified as spontaneous seizures occurring within 1 week of the stroke. The main outcome assessed was the occurrence of ES. The secondary outcome was to determine predictors of ES and create an ES prediction score.

Results

We screened 432 patients; of them, 291 were enrolled. ES occurred in 37 patients (12.7%). Cortical location (OR: 4.2), large artery disease subtype (OR: 2.9), mRS at presentation (OR: 1.4), use of anticoagulants (OR: 2.6), and hypertension (OR: 0.3) were significantly associated with the occurrence of ES. Patients with ES had a statistically significant worse clinical outcome at 3 months follow-up (P = 0.0072).

Conclusion

We could formulate an ES prediction tool using the following components: (a) cortical location, (b) large vessel stroke, (c) mRS at admission, (d) anticoagulant use, and (e) presence of hypertension. This tool might help in treating patients at high risk for ES with prophylactic ASD, thereby preventing seizures and their complications.

Impact of drug treatment and drug interactions in post-stroke epilepsy

Stroke is a huge burden on our society and this is expected to grow in the future due to the aging population and the associated co-morbidities. The improvement of acute stroke care has increased the survival rate of stroke patients, and many patients are left with permanent disability, which makes stroke the main cause of adult disability. Unfortunately, many patients face other severe complications such as post-stroke seizures and epilepsy. Acute seizures (ASS) occur within 1 week after the stroke while later occurring unprovoked seizures are diagnosed as post-stroke epilepsy (PSE). Both are associated with a poor prognosis of a functional recovery. The underlying neurobiological mechanisms are complex and poorly understood. There are no universal guidelines on the management of PSE. There is increasing evidence for several risk factors for ASS/PSE, however, the impacts of recanalization, drugs used for secondary prevention of stroke, treatment of stroke co-morbidities and antiseizure medication are currently poorly understood. This review focuses on the common medications that stroke patients are prescribed and potential drug interactions possibly complicating the management of ASS/PSE.

[Risk factors for post stroke epilepsy]

Stroke is the leading cause of death and disability in the world. The prevalence of post-stroke epilepsy increases with the increase in the number of stroke cases. Epilepsy may develop in 10% of post-stroke cases and first-diagnosed seizures may develop in 55%. Most often they occur in people who have had intracerebral or subarachnoid haemorrhage. A huge number of factors influence the development of post-stroke seizures and epilepsy. The role of some of them is not in doubt. However, in most cases, the influence of a factor remains controversial and participation in the development of post-stroke epilepsy is not fully proven. The management of post-stroke epilepsy is of great clinical importance, since patients with seizures after a stroke have a higher mortality and disability than those without seizures. Attacks worsen the quality of life of patients, can slow the recovery of functions damaged as a result of a stroke, and aggravate cognitive impairment. Social consequences of post-stroke epilepsy play an important role as well.

Antiseizure medications for post-stroke epilepsy: A real-world prospective cohort study

BACKGROUND AND PURPOSE

The management of post-stroke epilepsy (PSE) should ideally include prevention of both seizure and adverse effects; however, an optimal antiseizure medications (ASM) regimen has yet been established. The purpose of this study is to assess seizure recurrence, retention, and tolerability of older-generation and newer-generation ASM for PSE.

METHODS

This prospective multicenter cohort study (PROgnosis of Post-Stroke Epilepsy [PROPOSE] study) was conducted from November 2014 to September 2019 at eight hospitals. A total of 372 patients admitted and treated with ASM at discharge were recruited. Due to the non-interventional nature of the study, ASM regimen was not adjusted and followed standard hospital practices. The primary outcome was seizure recurrence in patients receiving older-generation and newer-generation ASM. The secondary outcomes were the retention and tolerability of ASM regimens.

RESULTS

Of the 372 PSE patients with ASM at discharge (median [IQR] age, 73 [64-81] years; 139 women [37.4%]), 36 were treated with older-generation, 286 with newer-generation, and 50 with mixed-generation ASM. In older- and newer-generation ASM groups (n = 322), 98 patients (30.4%) had recurrent seizures and 91 patients (28.3%) switched ASM regimen during the follow-up (371 [347-420] days). Seizure recurrence was lower in newer-generation, compared with the older-generation, ASM (hazard ratio [HR], 0.42, 95%CI 0.27-0.70; p = .0013). ASM regimen withdrawal and change of dosages were lower in newer-generation ASM (HR, 0.34, 95% CI 0.21-0.56, p < .0001).

CONCLUSIONS

Newer-generation ASM possess advantages over older-generation ASM for secondary prophylaxis of post-stroke seizures in clinical practice.

Statins for the Prevention of Post-Stroke Seizure and Epilepsy Development: A Systematic Review and Meta-Analysis

OBJECTIVES

Cerebrovascular disease is the leading cause of seizures and incident epilepsy of known etiology in older adults. Statins have increasingly garnered attention as a potential preventive strategy due to their pleiotropic effects beyond lipid-lowering, which may include neuroprotective and anti-epileptogenic properties. We aim to assess the evidence on statin use for prevention of post-stroke early-onset seizures and post-stroke epilepsy.

MATERIALS AND METHODS

We conducted a systematic review and meta-analysis in accordance with PRISMA guidelines, which was prospectively registered with PROSPERO (CRD42019144916). PubMed and Embase were searched from database inception to 05/2020 for English-language, full-text studies examining the association between statin use in adults and development of early-onset seizures (≤7 days post-stroke) or post-stroke epilepsy. Pooled analyses were based on random-effects models using the inverse-variance method.

RESULTS

Of 182 citations identified, 175 were excluded due to duplication or ineligibility. The 7 eligible publications were all cohort studies from East Asia or South America, with a total of 53,579 patients. Pre-stroke statin use was not associated with post-stroke epilepsy (3 studies pooled: OR 1.14, CI 0.91-1.42). However, post-stroke statin use was associated with lower risk of both early-onset seizures (3 studies pooled: OR 0.36, CI 0.25-0.53), and post-stroke epilepsy (6 studies pooled: OR 0.64, CI 0.46-0.88).

CONCLUSIONS

Review of 7 cohort studies suggested post-stroke, but not pre-stroke, statin use may be associated with reduced risk of early-onset seizures and post-stroke epilepsy. Further research is warranted to validate these findings in broader populations and better parse the temporal components of the associations.

Amazon rainforest rodents (Proechimys) are resistant to post-stroke epilepsy

There are no clinical interventions to prevent post-injury epilepsy, a common and devastating outcome after brain insults. Epileptogenic events that run from brain injury to epilepsy are poorly understood. Previous studies in our laboratory suggested Proechimys, an exotic Amazonian rodent, as resistant to acquired epilepsy development in post-status epilepticus models. The present comparative study was conducted to assess (1) stroke-related brain responses 24-h and 30 days after cortical photothrombosis and (2) post-stroke epilepsy between Proechimys rodents and Wistar rats, a traditional animal used for laboratory research. Proechimys group showed smaller volume of ischemic infarction and lesser glial activation than Wistar group. In contrast to Wistar rats, post-stroke decreased levels of pro-inflammatory cytokines and increased levels of anti-inflammatory mediators and growth factors were found in Proechimys. Electrophysiological signaling changes assessed by cortical spreading depression, in vitro and in vivo, showed that Wistar's brain is most severely affected by stroke. Chronic electrocorticographic recordings showed that injury did not lead to epilepsy in Proechimys whereas 88% of the Wistar rats developed post-stroke epilepsy. Science gains insights from comparative studies on diverse species. Proechimys rodents proved to be a useful animal model to study antiepileptogenic mechanisms after brain insults and complement conventional animal models.

Acute Seizures in Cerebral Venous Sinus Thrombosis: Risk Factors and Prognosis

BACKGROUND

Cerebral venous sinus thrombosis (CVST) often presents with acute seizures, and recurrent seizures may also be seen in the long term in some patients. The purpose of this retrospective study was to investigate the frequency and type of acute seizures and to define the risk factors.

METHODS

Sixty-two patients diagnosed with CVST between September 2007 and October 2018 were retrospectively evaluated for the occurrence of acute seizures. Seizures which developed as a presenting symptom or occurred within 2 weeks of diagnosis were defined as acute seizures. Demographic, clinical, and radiologic characteristics were compared between patients with or without acute seizures.

RESULTS

Twenty (32.3%) of the 62 CVST patients had acute seizures. Univariate analysis revealed a significant association between acute seizures and aphasia (P=0.03), motor deficit (P<0.001), sensory deficit (P=0.018), severe (≥3) modified Rankin Scale scores on admission (P=0.017), sagittal sinus thrombosis (P=0.037), cortical vein thrombosis (P<0.001), supratentorial lesions (P<0.001), and hemorrhagic lesions (P<0.001). Multivariate regression analysis identified supratentorial lesions (P=0.015, odds ratio: 9.131, 95% confidence interval: 1.525-54.687) and cortical vein thrombosis (P=0.034, odds ratio: 5.802, 95% confidence interval: 1.146-29.371) as independent factors for acute seizures. Although 25% of patients with acute seizures had recurrent seizures during hospitalization, only 2.6% of the 38 patients with long-term follow-up had recurrent seizures.

CONCLUSIONS

Approximately one third of patients with CVST had acute seizures. Cortical vein thrombosis, supratentorial, and especially hemorrhagic lesions were the most significant risk factors associated with acute seizures. Although seizure recurrence may occur early in the course, long-term recurrence is rare in CVST.

Poststroke epilepsy incidence, risk factors and treatment: German claims analysis

Objectives

To describe incidence, risk factors, and treatment of poststroke epilepsy (PSE) in Germany based on claims data.

Methods

Retrospective analysis of claims data from a German public sickness fund (AOK PLUS). Patients with acute stroke hospitalizations from January 01, 2011 and December 31, 2015 (index hospitalization) were followed for 12–72 months. Outcomes included incidence of PSE (patients with ≥2 seizure claims [during/after index hospitalization], or ≥1 seizure claim after index hospitalization), multivariate Cox‐regression analyses of time to seizure claim and death after index stroke hospitalization discharge, and antiepileptic drug (AED) treatment.

Results

Among 53 883 patients with stroke (mean follow‐up of 829.05 days [median 749]), 6054 (11.24%) had ≥1 seizure claim (mean age 73.95 years, 54.18% female). 2130 (35.18%) patients had a seizure claim during index hospitalization (indicative of acute symptomatic seizures). Estimated incidence of PSE (cases/1000 patient‐years) was 94.49 within 1 year. Risk of seizure claim following hospital discharge was higher in patients with hemorrhagic stroke (hazard ratio [HR] =1.13; p <.001) vs those with cerebral infarction. Seizure claim during index hospitalization was a risk factor for seizure claims after hospital discharge (HR =6.97; p <.001) and early death (HR =1.78; p <.001). In the first year of follow‐up, AEDs were prescribed in 73.75% of patients with seizure claims.

Conclusions

Incidence of PSE was in line with previous studies. Hemorrhagic stroke and seizure claim during index hospitalization were risk factors for seizure claims after hospital discharge. Most patients with seizure claims received AED treatment.

Seizures and Epilepsy After Stroke: Epidemiology, Biomarkers and Management

Stroke is the leading cause of seizures and epilepsy in older adults. Patients who have larger and more severe strokes involving the cortex, are younger, and have acute symptomatic seizures and intracerebral haemorrhage are at highest risk of developing post-stroke epilepsy. Prognostic models, including the SeLECT and CAVE scores, help gauge the risk of epileptogenesis. Early electroencephalogram and blood-based biomarkers can provide information additional to the clinical risk factors of post-stroke epilepsy. The management of acute versus remote symptomatic seizures after stroke is markedly different. The choice of an ideal antiseizure medication should not only rely on efficacy but also consider adverse effects, altered pharmacodynamics in older adults, and the influence on the underlying vascular co-morbidity. Drug-drug interactions, particularly those between antiseizure medications and anticoagulants or antiplatelets, also influence treatment decisions. In this review, we describe the epidemiology, risk factors, biomarkers, and management of seizures after an ischaemic or haemorrhagic stroke. We discuss the special considerations required for the treatment of post-stroke epilepsy due to the age, co-morbidities, co-medication, and vulnerability of stroke survivors.

Predictive Values of the SeLECT Score and IL-1β for Post-Stroke Epilepsy

PURPOSE

To establish a new prognostic tool for the prediction of post-stroke epilepsy (PSE) through combining the SeLECT score with IL-1β.

PATIENTS AND METHODS

This prospective observational study included 915 patients with acute ischemic stroke. The SeLECT score was calculated, and serum IL-1β levels were measured within 24 h of their admission. One unprovoked late seizure following the acute phase of stroke was diagnosed as PSE. All patients were divided into PSE group and non-PSE group according to the occurrence of PSE. Multivariate analysis was performed to determine the independent associations between the SeLECT score, IL-1β and PSE. Receiver operating characteristic (ROC) curve was employed to assess the predictive values of the SeLECT score, IL-1β and their combination for PSE.

RESULTS

Fifty-three patients occurred PSE within 1 year after stroke onset (5.8%). Multivariate analysis demonstrated that the SeLECT score [odds ratio (OR): 1.416, 95% confidence interval (CI): 1.191-1.863, P=0.013] and IL-1β (OR: 1.457, 95% CI: 1.215-1.894, P<0.001) were independent risk factors for PSE after adjusting for more than one comorbidity, stroke laterality, large-artery atherosclerosis, thrombolysis, age and use of statins. The AUC of the SeLECT score and IL-1β for predicting PSE was 0.756 (SE: 0.033, 95% CI: 0.692-0.819) and 0.811 (SE: 0.032, 95% CI: 0.748-0.875), respectively. The AUC of their combination was 0.933 (SE: 0.027, 95% CI: 0.880-0.985). Z test showed that the AUC of their combination was significantly higher than that of the SeLECT score or IL-1β alone (0.933 vs 0.756, Z=4.151, P<0.01; 0.933 vs 0.811, Z=2.914, P<0.01). Combination prediction of the SeLECT score and IL-1β for PSE had a high predictive value with a sensitivity of 88.06% and specificity of 82.37%.

CONCLUSION

The combination of the SeLECT score and IL-1β had a potential to act as a new prognostic tool for the prediction of PSE.

Risk Factors of Post-Stroke Epilepsy in Children; Experience from a Tertiary Center and a Brief Review of the Literature

OBJECTIVES

Acute seizures and post-stroke epilepsy have been reported more frequently in patients with pediatric stroke than adults. Acute seizures in the first days of a stroke may deteriorate stroke and ischemia-related neurodegeneration and contribute to the development of post-stroke epilepsy. In this study, we aimed to investigate risk factors for the development of post-stroke epilepsy in children with arterial ischemic stroke.

MATERIALS AND METHODS

We recruited 86 children with arterial ischemic stroke. We analyzed variables, including age at admission, gender, complaints at presentation, focal or diffuse neurologic signs, neurologic examination findings, laboratory investigations that were conducted at admission with stroke (complete blood cell count, biochemical-infectious-metabolic-immunological investigations, vitamin B12 levels, vitamin D levels), neuroimaging results, etiologies, time of the first seizure, time of remote seizures, and development of neurologic deficit retrospectively. Seizures during the first six hours after stroke onset were defined as 'very early seizures'. 'Early seizures' were referred to seizures during the first 48 h. Patients who experienced two or more seizures that occurred after the acute phase of seizures were classified as 'epileptic.' A binary logistic regression analysis was used to estimate risk factors.

RESULTS

An acute seizure was detected in 59% and post-stroke epilepsy developed in 41% of our cohort. Binary logistic regression analysis demonstrated that 'very early seizures' increased epilepsy risk six-fold. Epilepsy was 16 times higher in patients with 'early seizures'. Low vitamin D levels were defined as a risk factor for post-stroke epilepsy.

CONCLUSION

Seizures in the very early period (within the first six hours) are the most significant risk factors for the development of post-stroke epilepsy Further studies regarding seizure prevention and neuroprotective therapies are needed because post-stroke epilepsy will affect long term prognosis in patients with pediatric stroke.

Meta-analyzing count events over varying durations using the piecewise Poisson model: The case for poststroke seizures

Meta-analyzing count data can be challenging when follow-up time varies across studies. Simply pooling aggregate data over time-periods would result in biased estimates, which may erroneously inform clinical decision-making. In this study, we exploit the convolution property of the Poisson distribution to develop a likelihood for observed cumulative counts over varying follow-up periods, where different Poisson distributions are used to represent the data generating processes for the latent counts in pre-defined successive intervals of follow-up. We illustrate this approach using an example of poststroke seizures, a case in which risk may change over time, and mimic its survival duration with time-varying hazard. Data were extracted from observational studies (1997-2016) reporting poststroke seizures over a maximum of 10 years of follow-up. Three clinically meaningful follow-up time intervals were considered: 0 to 7 days, 8 to 365 days, and 1 to 10 years poststroke. External validation was performed using claims data. Results suggest the incidence rate of seizures was 0.0452 (95% confidence interval: 0.0429, 0.0475), 0.0001 (0, 0.016), and 0.0647 (0.0441, 0.0941) for the three time intervals, respectively, indicating that the risk of seizures changes over time poststroke. We found that the model performed well against the incidence rate of seizures among actual retrospective cohort from claims data. The piecewise Poisson model presents a flexible way to meta-analyze count data over time and mimic survival curves. The results of the piecewise Poisson model are readily interpretable and may spur meaningful clinical action. The method may also be applied to other diseases. HIGHLIGHTS: It is challenging to perform a meta-analysis when follow-up time varies across studies. Ideally, outcomes over different time-periods should be pooled with individual patient-level data (IPD). A new model was developed to meta-analyze count data over time using aggregate-level data from previous published studies. The piecewise Poisson model could be a useful tool to estimate time-vary hazards given available data, and mimic survival curves over time which would be readily interpretable.

[Electroencephalography in acute stroke]

OBJECTIVE

To determine the incidence of non-convulsive status epilepticus, epileptiform activity, rhythmic and periodic patterns in patients with acute stroke.

MATERIAL AND METHOD

An analysis of electroencephalography (EEG) in 86 stroke patients in the neurointensive care unit of the tertiary medical center was performed. Criteria for starting EEG recording were epileptic seizures or clinical suspicion of uncontrolled epileptic status. The ictal-interictal continuum biomarkers and the diagnostic value of EEG for prediction of survival and recovery were assessed.

RESULTS

Pathological changes on EEG were recorded in 84% of patients. These patients showed the absence of the dominant occipital rhythm (66%) and hemispheric slowing (42%). Diffuse slowing below the theta range was observed in 41% of patients. EEG reactivity was absent in 20%. Sporadic epileptiform discharges were recorded in 36% of patients and rhythmic and periodic patterns in 26%. Reliable predictors of the unfavorable outcome were the absence of dominant occipital rhythm, lack of reactivity, and low amplitude of the background EEG. No association between the recording of epileptiform activity and the probability of death was shown.

CONCLUSION

The most useful EEG biomarkers for predicting survival are amplitude, dominant frequency of background EEG activity and reactivity to external stimulus. Sporadic epileptiform discharges, rhythmic, and periodic patterns are not mandatory associated with a negative prognosis in stroke patients.

Long-term efficacy and safety of eslicarbazepine acetate monotherapy for adults with newly diagnosed focal epilepsy: An open-label extension study

Objective

To assess the efficacy, safety, and tolerability of eslicarbazepine acetate (ESL) monotherapy during long‐term treatment.

Methods

An open‐label extension (OLE) study was conducted in adults completing a phase 3, randomized, double‐blind, noninferiority trial, during which they had received monotherapy with either once‐daily ESL or twice‐daily controlled‐release carbamazepine (CBZ‐CR) for newly diagnosed focal epilepsy. In the OLE study, all patients received ESL (800‐1600 mg/d) for 2 years. Primary efficacy outcome was retention time (from baseline of the OLE study). Secondary efficacy assessments included seizure freedom rate (no seizures during the OLE study) and responder rate (≥50% seizure frequency reduction from baseline of double‐blind trial). Safety assessments included evaluation of treatment‐emergent adverse events (TEAEs).

Results

Of 206 randomized patients, 96 who received ESL in the double‐blind trial (ESL/ESL) and 88 who received CBZ‐CR in the double‐blind trial (CBZ‐CR/ESL) were treated with ESL monotherapy (89.3% overall). Treatment retention time was similar between groups, with low probability of ESL withdrawal overall (<0.07 at any time). After 24 months, the probability of ESL withdrawal was 0.0638 (95% confidence interval [CI] = 0.0292‐0.1366) in the ESL/ESL group and 0.0472 (95% CI = 0.0180‐0.1210) in the CBZ‐CR/ESL group. Seizure freedom rates were 90.6% (ESL/ESL) and 80.7% (CBZ‐CR/ESL; P = .0531). Responder rates remained >80% in both groups throughout the study. Incidence of serious TEAEs was similar between groups (7.3% vs 5.7%; 0% vs 1.1% possibly related), as were the incidences of TEAEs considered at least possibly related to treatment (17.7% vs 18.2%) and TEAEs leading to discontinuation (3.1% vs 4.5%). The types of TEAEs were generally consistent with the known safety profile of ESL.

Significance

ESL monotherapy was efficacious and generally well tolerated over the long term, including in patients who transitioned from CBZ‐CR monotherapy. No new safety concerns emerged.

Blood biomarkers predictive of epilepsy after an acute stroke event

OBJECTIVE

Blood biomarkers have not been widely investigated in poststroke epilepsy. In this study, we aimed to describe clinical factors and biomarkers present during acute stroke and analyze their association with the development of epilepsy at long term.

METHODS

A panel of 14 blood biomarkers was evaluated in patients with ischemic and hemorrhagic stroke. Biomarkers were normalized and standardized using Z-scores. Stroke and epilepsy-related variables were also assessed: stroke severity, determined by National Institutes of Health Stroke Scale (NIHSS) score, stroke type and cause, time from stroke to onset of late seizures, and type of seizure. Multiple Cox regression models were used to identify clinical variables and biomarkers independently associated with epilepsy.

RESULTS

From a cohort of 1115 patients, 895 patients were included. Mean ± standard deviation (SD) age was 72.0 ± 13.1 years, and 57.8% of patients were men. Fifty-one patients (5.7%) developed late seizures, with a median time to onset of 232 days (interquartile range [IQR] 86-491). NIHSS score ≥8 (P < .001, hazard ratio [HR] 4.013, 95% confidence interval [CI] 2.123-7.586) and a history of early onset seizures (P < .001, HR 4.038, 95% CI 1.802-9.045) were factors independently associated with a risk of developing epilepsy. Independent blood biomarkers predictive of epilepsy were high endostatin levels >1.203 (P = .046, HR 4.300, 95% CI 1.028-17.996) and low levels of heat shock 70 kDa protein-8 (Hsc70) <2.496 (P = .006, HR 3.795, 95% CI 1.476-9.760) and S100B <1.364 (P = .001, HR 2.955, 95% CI 1.534-5.491). The risk of epilepsy when these biomarkers were combined increased to 17%. The area under the receiver-operating characteristic (ROC) curve of the predictive model was stronger when clinical variables were combined with blood biomarkers (74.3%, 95% CI 65.2%-83.3%) than when they were used alone (68.9%, 95% CI 60.3%-77.6%).

SIGNIFICANCE

Downregulated S100B and Hsc70 and upregulated endostatin may assist in prediction of poststroke epilepsy and may provide additional information to clinical risk factors. In addition, these data are hypothesis-generating for the epileptogenic process.

Cardiogenic cerebral infarction in the parietal lobe predicts the development of post-stroke epilepsy

PURPOSE

Post-stroke epilepsy (PSE) is a major late complication of cardioembolic cerebral infarction. However, few studies have examined the epileptogenicity and characteristics of first-occurrence cardioembolic cerebral infarctions.

METHODS

This retrospective study included 93 consecutive patients with old cardioembolic cerebral infarctions who were classified into two groups based on their epileptic history: patients presenting with PSE or stroke without seizure (SWS). Each patient was diagnosed with an epileptic seizure subtype and treated with appropriate anti-epileptic therapy after admission. We evaluated clinical characteristics, laboratory results, and intracranial infarct areas. The sizes of these areas were measured using MRI diffusion-weighted image (DWI) of each patient after their first stroke. The volume was calculated by multiplying the total slice area with the slice thickness.

RESULTS

PSE was diagnosed in 43 (46.2 %) of 93 patients. The mean (± SD) time from infarction onset to the first seizure in the PSE group was 22.5 ± 31.6 months. The PSE group exhibited significantly more atrial fibrillation (p = 0.022) and higher glucose levels (p < 0.001) compared with the SWS group. The most common PSE seizure type was focal to bilateral tonic-clonic seizure (61.0 %). Although DWI did not reveal any significant differences in the volume of infarctions between the two groups, the involvement of the parietal lobe in infarction of the PSE group (69.8 %) upon first admission was significantly higher (p = 0.006) than that of the SWS group (40.0 %). Multiple logistic regression analysis revealed that parietal lobe involvement in infarction (OR 4.95; 95 % CI 1.25-19.60; p = 0.023) was a significant independent predictor of PSE.

CONCLUSION

The involvement of the parietal lobe in infarction was a significant independent predictor of PSE. Dysfunction of the parietal lobe might play a critical role in the epileptogenesis of PSE.

Lacosamide in patients with epilepsy of cerebrovascular etiology

OBJECTIVES

To assess tolerability and efficacy of lacosamide in adults with cerebrovascular epilepsy etiology (CVEE).

MATERIALS AND METHODS

Exploratory post hoc analyses of a double-blind, initial monotherapy trial of lacosamide vs carbamazepine-controlled release (carbamazepine-CR) (SP0993; NCT01243177); a double-blind conversion to lacosamide monotherapy trial (SP0902; NCT00520741); and an observational study of adjunctive lacosamide added to one antiepileptic drug (SP0973 VITOBA; NCT01098162). Patients with CVEE were identified based on epilepsy etiology recorded at baseline.

RESULTS

In the initial monotherapy trial, 61 patients had CVEE (lacosamide: 27; carbamazepine-CR: 34). 20 (74.1%) patients on lacosamide (27 [79.4%] on carbamazepine-CR) reported treatment-emergent adverse events (TEAEs), most commonly (≥10%) headache, dizziness, and fatigue (carbamazepine-CR: headache, dizziness). A numerically higher proportion of patients on lacosamide than carbamazepine-CR completed 6 months (22 [81.5%]; 20 [58.8%]) and 12 months (18 [66.7%]; 17 [50.0%]) treatment without seizure at last evaluated dose. In the conversion to monotherapy trial, 26/30 (86.7%) patients with CVEE reported TEAEs, most commonly (≥4 patients) dizziness, convulsion, fatigue, headache, somnolence, and cognitive disorder. During lacosamide monotherapy, 17 (56.7%) patients were 50% responders and six (20.0%) were seizure-free. In the observational study, 36/83 (43.4%) patients with CVEE reported TEAEs, most commonly (≥5%) fatigue and dizziness. Effectiveness was assessed for 75 patients. During the last 3 months, 60 (80%) were 50% responders and 42 (56.0%) were seizure-free.

CONCLUSIONS

These exploratory post hoc analyses suggested lacosamide was generally well tolerated and effective in patients with CVEE, with data from the initial monotherapy trial suggesting numerically better efficacy than carbamazepine-CR.

Modeling poststroke epilepsy and preclinical development of drugs for poststroke epilepsy

Stroke is a severe clinical issue for global public health, representing the third leading cause of death and a major cause of disability in developed countries. Progresses in the pharmacological treatment of the acute stroke have given rise to a significant decrease in its mortality rate. However, as a result, there has been an increasing number of stroke survivors living with disability worldwide. Poststroke epilepsy (PSE) is a common clinical complication following stroke. Seizures can arise in close temporal association with stroke damage and/or after a variably longer interval. Overall, PSE have a good prognosis; in fact, its responding rate to antiepileptic drugs (AEDs) is higher than other types of epilepsy. However, regarding pharmacological treatment, some issues are still unresolved. To this aim, a deeper understanding of mechanisms underlying the transformation of infarcted tissue into an epileptic focus or better from a nonepileptic brain to an epileptic brain is also mandatory for PSE. However, studying epileptogenesis in patients with PSE clearly has several limitations and difficulties; therefore, modeling PSE is crucial. Until now, different experimental models have been used to study the etiopathology of cerebrovascular stroke with or without infarction, but few studies focused on poststroke epileptogenesis and PSE. In this review, we show a brief overview on the features emerging from preclinical research into experimental PSE, which could affect the discovery of biomarkers and therapy strategies for poststroke epileptogenesis. This article is part of the Special Issue "Seizures & Stroke".

Post-stroke epilepsy in an ischemic stroke cohort-Incidence and diagnosis

OBJECTIVES

Stroke is a common cause of adult-onset epilepsy (post-stroke epilepsy, PSE). Despite an increasing awareness, there is a concern for underdiagnosis of the condition. We aimed to study the adherence to the latest updated epilepsy definition, as well as the incidence and diagnosis of PSE in an ischemic stroke cohort admitted to a tertiary University Hospital.

MATERIALS AND METHODS

We retrospectively investigated the occurrence and diagnosis of unprovoked seizures and PSE in all ischemic stroke patients admitted to Karolinska University Hospital in Stockholm during 2015 and registered in the Swedish Stroke Register. Patient records were scrutinized for the presence of post-stroke seizures/epilepsy.

RESULTS

A total of 240 patients fulfilling the inclusion criteria were surveyed. Median follow-up time was 1062 days (IQR 589-1195 days). Thirteen patients were diagnosed with PSE according to the study criteria, the incidence of PSE 23/1000 person-years (95% CI 13-38/1000 person-years). Median time to PSE from stroke-onset was 237 days (IQR 33-688). Eleven of 13 PSE patients received an epilepsy diagnosis, eight patients after one unprovoked seizure, and three patients after two.

CONCLUSIONS

The majority of PSE patients were given a correct epilepsy diagnosis and treated with antiepileptic drugs. However, this study suggests that there still is potential for improvement in the adherence to the latest updated epilepsy definition. The incidence of PSE in a Swedish ischemic stroke cohort using updated epilepsy definitions is similar to previous studies. Larger studies are needed to confirm our findings on the incidence of PSE.

Effect of single-session transcranial direct current stimulation on cognition in Parkinson's disease

AIMS

Nonmotor symptoms (NMS) such as cognitive impairment and impulse-control disorders in Parkinson's disease (PD) remain a therapeutic challenge. Transcranial direct current stimulation (tDCS) has emerged as a promising alternative, although its immediate effects on NMS have been less well defined. In this randomized, sham-controlled, crossover study, we aimed to explore the single-session tDCS effects on cognitive performance in PD.

METHODS

Ten nondemented patients with PD completed two sessions in counterbalanced order, receiving 20 minutes of either 2 mA anodal or sham tDCS over the left dorsolateral prefrontal cortex (DLPFC). During stimulation, they performed the visual working memory and go/no-go tasks. Performance of the tasks was compared between the two conditions.

RESULTS

Single-session anodal tDCS over the left DLPFC did not significantly improve cognitive tasks in PD compared with sham (P > .05).

CONCLUSION

Single-session tDCS is ineffective in improving visual working memory and inhibitory control in PD. Further research may worth exploring alternative tDCS parameters, ideally with repeated sessions and concomitant training.

Poststroke epilepsy: current perspectives on diagnosis and treatment

Seizures and epilepsy are quite a common outcome of arterial ischemic stroke (AIS) both in pediatric and adult patients, with distinctly higher occurrence in children. These poststroke consequences affect patients' lives, often causing disability. Poststroke seizure (PSS) may also increase mortality in patients with AIS. Early PSS (EPSS) occurring up to 7 days after AIS, late PSS (LPSS) occurring up to 2 years after the onset of AIS, as well as poststroke epilepsy (PSE) can be distinguished. However, the exact definition and cutoff point for PSE should be determined. A wide range of risk factors for seizures and epilepsy after AIS are still being detected and analyzed. More accurate knowledge on risk factors for PSS and PSE as well as possible prediction of epileptic seizures after the onset of AIS may have an impact on improving the prevention and treatment of PSE. The aim of the present review was to discuss current perspectives on diagnosis and treatment of PSS and PSE, both in adult and paediatric patients.

Poststroke seizure: optimising its management

Seizure after stroke or poststroke seizure (PSS) is a common and very important complication of stroke. It can be divided into early seizure and late seizure, depending on seizure onset time after the stroke. It has been reported that ischaemic and haemorrhagic stroke accounts for about 11% of all adult epilepsy cases and 45% of epilepsy cases over 60 years of age. However, there are no reliable guidelines in clinical practice regarding most of the fundamental issues of PSS management. In recent years there has been an increased interest in the study of PSS which may give clinical practitioners a better picture of how to optimise PSS management. Studies have indicated two peaks in PSS occurrence—the first day and 6–12 months after a stroke. Haemorrhagic stroke, cortical involvement, severity of initial neurological deficit, younger patients (<65 years of age), family history of seizures and certain genetic factors carry a higher risk of PSS. The use of continuous electroencephalogram has demonstrated significant benefits in capturing interictal or ictal abnormalities, especially in cases of non-convulsive seizures and non-convulsive status epilepticus. Current available data indicated that there was no significant difference in antiepileptic efficacy among most of the antiepileptic drugs (AEDs) in PSS. Levetiracetam and lamotrigine are the most studied newer generation AEDs and have the best drug tolerance. The purpose of this review is to summarise the recent advances in PSS research and focus on the most important practice issues of PSS management.

Transient and permanent arterial occlusions modeling poststroke epilepsy in aging rats

The pathophysiological mechanisms of epileptogenesis following ischemic stroke in the aged brain are not well understood, largely due to limited developments in animal modeling of poststroke epilepsy (PSE). A recent study in our laboratory (Kelly et al., 2018) using transient (3 h) unilateral middle cerebral artery (MCA) and common carotid artery (CCA) occlusion (MCA/CCAo) in 4- and 20-month-old Fischer (F344) rats resulted in epileptic seizures in both age groups; age and infarction factors independently had effects on seizure frequency. We hypothesized that permanent unilateral MCA/CCAo, a simpler model, was capable of producing results comparable to those of transient MCA/CCAo. In this study, we performed permanent MCA/CCAo and compared it to transient MCA/CCAo in 76 4-, 12-, and 20-month-old F344 rats; 41 (54%) animals experienced early, unexpected mortality. The remaining 35 (46%) animals had depth electrodes implanted. Prior to implantation of depth electrodes, 9 (26%) of these 35 animals (26%) were monitored periodically by video alone before video-EEG monitoring (17,837 h total) to assess the potential development of PSE. No EEG recordings were obtained from 12- or 20-month-old transient occlusion or 20-month-old permanent occlusion animals due to premature deaths. Five animals (14%) demonstrated epileptic seizure activity after MCA/CCAo: one 4-month-old transient occlusion animal, one 4-month-old permanent occlusion animal, and three 12-month-old permanent occlusion animals. Of these 5 animals, all but the 4-month-old permanent animal demonstrated 1-4 Hz spike-wave discharges variably associated with inactivity or frank motor arrest, and 2 animals (4- and 12-month-old permanent) demonstrated generalized ictal EEG discharges associated with grade 5 convulsive activity. All animals monitored with video-EEG demonstrated generalized 7-9 Hz spike-wave discharges, innate in F344 animals and distinct from lesion-induced epileptic seizures. Gross inspection of brains revealed variability in lesion presence and size among age groups and occlusion types. Comparison of infarct volumes of permanent MCA/CCAo animals (2.9 ± 1.29 mm³, n = 6) with those of transient MCA/CCAo animals (1.7 ± 0.31 mm³, n = 3) was not significant (p = 0.44) due to the small sample size. Timm staining revealed no evidence of mossy fiber sprouting in 7 animals tested, only one of which was known to be epileptic (4-month-old transient). These results provide evidence of focal nonconvulsive electrographic ictal discharges and behavioral seizures in both permanent and transient MCA/CCAo animals lesioned at 4- or 12-months-of-age and support the use of arterial ligation as a viable method for modeling PSE.

Treatment with antiepileptic drugs in patients with stroke. A change in clinical practice may be required

BACKGROUND

Stroke prevention is an important socio-economic aim. Epilepsy and antiepileptic drugs (AEDs), roughly divided into enzyme-inducers and non-enzyme-inducers, have been associated with increased risk of stroke.

METHODS

A retrospective review of patients admitted with a diagnosis of anytime stroke and taking at least one AED was performed. A subgroup of subjects admitted for acute strokes was separately studied. Potential interactions between AEDs and other consumed medications were identified using MicroMedex and Lexi-Interact.

RESULTS

The study included 827 patients, 59% of them using 5-10 medications. Two thirds of the patients received at least one enzyme-inducer AED, with phenytoin being the most commonly used AED (38% of the patients). Among the subgroup of 82 patients admitted for stroke, 61% were prescribed AEDs after the stroke. More patients had large vessel and embolic strokes among these than among the patients that had strokes while on AEDs. Statins, antiplatelet drugs, antidiabetics and calcium channel blockers (CCBs) were the most frequently used non-AED drugs, by 56, 55, 30 and 28%, respectively. The most common combinations between AEDs and non-AED medications bearing risk for potential major interactions were those of AEDs with statins, warfarin, calcium channel blockers and anti-depressants.

CONCLUSIONS

A change in the AEDs prescription practice in stroke patients should be implemented, to avoid interactions with major groups of other medications prescribed to these patients.

Outcome and predictive factors in post-stroke seizures: A retrospective case-control study

PURPOSE

To evaluate clinical, radiographic, and electrophysiological features in the development and prognosis of ischemic post-stroke seizures (PSS).

METHOD

A retrospective study of 1119 patient records was performed between January 2006 and December 2016. After selection, 42 patients with seizures due to ischemic stroke were matched to a control group of 60 patients where seizures were absent. Stroke size and severity were analyzed using ASPECTS and NIHSS, respectively. Hemorrhagic transformation graded by ECASS III classification. Outcomes were assessed using the modified Rankin Scale. Fisher's exact test assessed categorical variables, and Mann-Whitney tested continuous variables.

RESULTS

Forty-two patients experienced PSS (22 females; median age 72.5 years) and were matched with 60 control subjects that had ischemic stroke without seizures. Focal seizures were present in 42.9% (18/42), and focal to bilateral convulsions in 57.1% (24/42). Stroke localization and severity did not differ (p = 0.6 and 0.21, respectively). Stroke size in anterior circulation was larger in PSS patients (median ASPECTS 6 vs 8 [p = 0.01]). Posterior circulation stroke size was similar in both groups. The presence of hemorrhage was the primary risk factor for PSS (61.9%) compared to controls (36.7%), p = 0.01. The presence of laminar necrosis (LN) (47.6% vs 21.6%, p = 0.005) and hemosiderin deposition (38.1% vs 18.3%, p = 0.02) were most predictive. PSS patients demonstrated worse outcomes than the controls (median mRS 3 vs 2, [p=<0.001]) with a median follow up of 14.8 and 20.7 months, respectively.

CONCLUSIONS

The size of anterior infarction, presence of blood products within the infarct bed, and especially LN predicted PSS.

Treatment of epilepsy in multiple sclerosis

PURPOSE

The prevalence of epilepsy is increased in multiple sclerosis (MS), but information on AED treatment and seizure outcome is scarce. We describe epilepsy characteristics including the use of AEDs and proportion of seizure-free patients at two tertiary hospitals in Sweden.

METHOD

We retrospectively studied electronic medical records of all patients with a diagnosis of MS and seizures at Sahlgrenska university hospital and Uppsala university hospital. Clinical data were reviewed until 2017.

RESULTS

We identified a total of 62 MS patients with at least one seizure. Median age at the first seizure (before or after MS) was 41 years (range 0-80). The most common MS disease course at the first seizure was secondary progressive MS, the neurological disability was considerable, and most patients had several MRI lesions at their first seizure. The first EEG demonstrated epileptiform discharges in 38% and unspecific pathology in 40%. Current seizure status could be determined for 37 patients. Out of these, 46% had been seizure free for more than one year at last follow-up. The majority of patients (65%) were on monotherapy at last follow-up. Carbamazepine was the most commonly used first AED, with a retention rate of 52%. No individual AED was associated with a particularly high rate of seizure freedom. The most common reason for discontinuation of the first AED was side-effects.

CONCLUSION

Seizure freedom rates were low, perhaps indicating a need for higher ambitions in management. Side effects of AEDs may be a particular concern when treating epilepsy in patients with MS.