Seizures in acute stroke: incidence, risk factors and prognosis

Post-stroke epilepsy: From clinical predictors to possible mechanisms

BACKGROUND

Stroke is the most common cause of newly diagnosed epilepsy in the elderly, ahead of degenerative disorders, brain tumors, and head trauma. Stroke accounts for 30-50% of unprovoked seizures in patients aged ≥ 60 years. This review discusses the current understanding of epidemiology, risk factors, mechanisms, prevention, and treatment opportunities for post-stroke epilepsy (PSE).

METHODS

We performed a literature search in the PubMed and Cochrane Library databases. The keywords "stroke, epilepsy", "stroke, seizure", "post-stroke seizure", "post-stroke epilepsy" were used to identify the clinical and experimental articles on PSE. All resulting titles and abstracts were evaluated, and any relevant article was considered. The reference lists of all selected papers and reference lists of selected review papers were manually analyzed to find other potentially eligible articles.

RESULTS

PSE occurs in about 6% of stroke patients within several years after the event. The main risk factors are cortical lesion, initial stroke severity, young age and seizures in acute stroke period (early seizures, ES). Other risk factors, such as a cardioembolic mechanism or circulation territory involvement, remain debated. The role of ES as a risk factor of PSE could be underestimated especially in young age. Mechanism of epileptogenesis may involve gliosis scarring, alteration in synaptic plasticity, etc.; and ES may enhance these processes. Statins especially in the acute period of stroke are possible agents for PSE prevention presumably due to their anticonvulsant and neuroprotection effects. Antiepileptic drugs (AED) monotherapy is enough for seizure prevention in most cases of PSE; but no evidence was found for its efficiency against epileptic foci formation. The growing interest in PSE has led to a notable increase in the number of published articles each year. To aid in navigating this expanding body of literature, several tables are included in the manuscript.

CONCLUSION

Further studies are needed for better understanding of the pathophysiology of PSE and searching the prevention strategies.

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.

Outcomes in Patients With Poststroke Seizures: A Systematic Review and Meta-Analysis

Importance

Published data about the impact of poststroke seizures (PSSs) on the outcomes of patients with stroke are inconsistent and have not been systematically evaluated, to the authors' knowledge.

Objective

To investigate outcomes in people with PSS compared with people without PSS.

Data Sources

MEDLINE, Embase, PsycInfo, Cochrane, LILACS, LIPECS, and Web of Science, with years searched from 1951 to January 30, 2023.

Study Selection

Observational studies that reported PSS outcomes.

Data Extraction and Synthesis

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses checklist was used for abstracting data, and the Joanna Briggs Institute tool was used for risk-of-bias assessment. Data were reported as odds ratio (OR) and standardized mean difference (SMD) with a 95% CI using a random-effects meta-analysis. Publication bias was assessed using funnel plots and the Egger test. Outlier and meta-regression analyses were performed to explore the source of heterogeneity. Data were analyzed from November 2022 to January 2023.

Main Outcomes and Measures

Measured outcomes were mortality, poor functional outcome (modified Rankin scale [mRS] score 3-6), disability (mean mRS score), recurrent stroke, and dementia at patient follow-up.

Results

The search yielded 71 eligible articles, including 20 110 patients with PSS and 1 166 085 patients without PSS. Of the participants with PSS, 1967 (9.8%) had early seizures, and 10 605 (52.7%) had late seizures. The risk of bias was high in 5 studies (7.0%), moderate in 35 (49.3%), and low in 31 (43.7%). PSSs were associated with mortality risk (OR, 2.1; 95% CI, 1.8-2.4), poor functional outcome (OR, 2.2; 95% CI, 1.8-2.8), greater disability (SMD, 0.6; 95% CI, 0.4-0.7), and increased dementia risk (OR, 3.1; 95% CI, 1.3-7.7) compared with patients without PSS. In subgroup analyses, early seizures but not late seizures were associated with mortality (OR, 2.4; 95% CI, 1.9-2.9 vs OR, 1.2; 95% CI, 0.8-2.0) and both ischemic and hemorrhagic stroke subtypes were associated with mortality (OR, 2.2; 95% CI, 1.8-2.7 vs OR, 1.4; 95% CI, 1.0-1.8). In addition, early and late seizures (OR, 2.4; 95% CI, 1.6-3.4 vs OR, 2.7; 95% CI, 1.8-4.1) and stroke subtypes were associated with poor outcomes (OR, 2.6; 95% CI, 1.9-3.7 vs OR, 1.9; 95% CI, 1.0-3.6).

Conclusions and Relevance

Results of this systematic review and meta-analysis suggest that PSSs were associated with significantly increased mortality and severe disability in patients with history of stroke. Unraveling these associations is a high clinical and research priority. Trials of interventions to prevent seizures may be warranted.

Epilepsy in cerebral amyloid angiopathy: an observational retrospective study of a large population

OBJECTIVE

Cerebral amyloid angiopathy (CAA) is a major cause of spontaneous intracranial hemorrhage in older adults. Epilepsy represents a possible sequela of the disease. To date, studies on epilepsy in CAA are lacking, and the few data available mainly focus on CAA-related inflammation (CAA-ri), the inflammatory form of the disease.

METHODS

In this retrospective observational study, we consecutively recruited CAA patients observed over a time span of 10 years, collecting demographic, clinical, and instrumental data. Significant baseline characteristics were evaluated as potential risk factors for the development of epilepsy in the CAA population, and in the subgroups of CAA-ri and CAA without inflammatory reaction (CAA-nri). The effect of potential risk factors for epilepsy was measured as odds ratio with 95% confidence interval.

RESULTS

Within 96 recruited CAA cases, 33 (34.4%) developed epilepsy during follow-up (median = 13.5 months). The prevalent type of seizure was focal (81.3%); 12.1% of the epileptic patients presented status epilepticus, and 6.1% developed drug-resistant epilepsy. Electroencephalographic traces revealed slow and epileptic discharge activity in the majority of epileptic patients, but also in those without epilepsy. The presence of focal or disseminated cortical superficial siderosis (cSS) was associated with an increased risk of epilepsy in the CAA-nri group, and the association with CAA-ri and epilepsy was present in the overall population.

SIGNIFICANCE

Epilepsy is a common manifestation during the course of CAA, where CAA-ri and cSS represent predisposing factors for the development of seizures. These data suggest the importance of a deep characterization of CAA patients, to better select those more prone to develop epilepsy.

Post-stroke seizures: risk factors and management after ischemic stroke

Stroke is the leading cause of epilepsy in the elderly, ahead of degenerative diseases, tumors and head injuries. It constitutes a significant complication and a considerable comorbidity. The aim of our study was to describe the main factors implicated in the occurrence of post-stroke seizures and to identify the predictors of seizure recurrence. We conducted a descriptive, retrospective, monocentric study from January 2010 to December 2019, including patients who presented seizures following an ischemic stroke. We classified these seizures according to the International League Against Epilepsy (ILAE) into acute symptomatic seizures (ASS) if they occur within seven days of stroke, and unprovoked seizures (US) if they occur after more than one week. Clinical, para-clinical, therapeutic and follow-up data were statistically analyzed and compared. A total of 52 patients were included (39 men, 13 women; median age 55.1 years). 21 cases (40%) had ASS and the remaining 31 cases (60%) presented US. Young age below 65 years (71%), middle cerebral artery infarcts (83%), and cortical localization (87%) were the main factors depicted in our series. Parietal lobe infarction was more associated with US than ASS (p = 0.035). 24 patients (46%) have presented a recurrence of seizures (8/21 of ASS and 16/31 of US). The use of sodium valproate in monotherapy was identified as a recurrence risk factor (p = 0.013). In patients with post-stroke seizures, parietal lobe infarcts are more associated with US. We identified a higher risk of seizure recurrence in patients treated with sodium valproate monotherapy.

Epilepsy in Cerebrovascular Diseases: A Narrative Review

BACKGROUND

Epilepsy is a common comorbidity of cerebrovascular disease and an increasing socioeconomic burden.

OBJECTIVE

We aimed to provide an updated comprehensive review on the state of the art about seizures and epilepsy in stroke, cerebral haemorrhage, and leukoaraiosis.

METHODS

We selected English-written articles on epilepsy, stroke, and small vessel disease up until December 2021. We reported the most recent data about epidemiology, pathophysiology, prognosis, and management for each disease.

RESULTS

The main predictors for both ES and PSE are the severity and extent of stroke, the presence of cortical involvement and hemorrhagic transformation, while PSE is also predicted by younger age at stroke onset. Few data exist on physiopathology and seizure semiology, and no randomized controlled trial has been performed to standardize the therapeutic approach to post-stroke epilepsy.

CONCLUSION

Some aspects of ES and PSE have been well explored, particularly epidemiology and risk factors. On the contrary, few data exist on physiopathology, and existing evidence is mainly based on studies on animal models. Little is also known about seizure semiology, which may also be difficult to interpret by non-epileptologists. Moreover, the therapeutic approach needs standardization as regards indications and the choice of specific ASMs. Future research may help to better elucidate these aspects.

Silencing TLR4 using an ultrasound-targeted microbubble destruction-based shRNA system reduces ischemia-induced seizures in hyperglycemic rats

The toll-like receptor 4 (TLR4) pathway is involved in seizures. We investigated whether ultrasound-targeted microbubble destruction (UTMD)-mediated delivery of short hairpin RNA (shRNA) targeting the TLR4 gene (shRNA-TLR4) can reduce ischemia-induced seizures in rats with hyperglycemia. A total of 100 male Wistar rats were randomly assigned to five groups: (1) Sham; (2) normal saline (NS); (3) shRNA-TLR4, where rats were injected with shRNA-TLR4; (4) shRNA-TLR4 + US, where rats were injected with shRNA-TLR4 followed by ultrasound (US) irradiation; and (5) shRNA-TLR4 + microbubbles (MBs) + US, where rats were injected with shRNA-TLR4 mixed with MBs followed by US irradiation. Western blot and immunohistochemical staining were used to measure TLR4-positive cells. Half of the rats in the NS group developed tonic-clonic seizures, and TLR4 expression in the CA3 region of the hippocampus was increased in these rats. In addition, the NS group showed an increased number of TLR4-positive cells compared with the Sham group, while there was a decreased number of TLR4-positive cells in the shRNA, shRNA + US, and shRNA + MBs + US groups. Our findings indicate that the TLR4 pathway is involved in the pathogenesis of ischemia-induced seizures in hyperglycemic rats and that UTMD technology may be a promising strategy to treat brain diseases.

Cortical Involvement of a Recent Infarct Contralateral to Early Focal Seizures in Ischemic Stroke

Objective To investigate the frequency and clinical characteristics of ischemic stroke patients with early seizures, especially with cortical involvement contralateral to their focal seizures. Methods We retrospectively studied patients with ischemic stroke admitted to our hospital. We compared the clinical characteristics of patients with and without early seizures (occurring within seven days of the stroke onset). In addition, we divided the patients with early focal seizures into two groups (patients with and without cortical involvement of a recent infarct contralateral to their focal seizure) and compared the clinical characteristics of the groups. Results Of the 5,806 patients with ischemic stroke, 65 (1.2%) were diagnosed with early seizures. A history of ischemic stroke (odds ratio [OR] 1.71), a history of seizures (OR 27.58), and a National Institutes of Health Stroke Scale score on admission (OR 1.07) were significant and independent factors associated with the presence of early seizures. Of these 65 patients, 56 had focal seizures, while the others had generalized or undetermined seizures. Cortical involvement of a recent infarct contralateral to their focal seizures was observed in 24 of these 56 patients (43%). Glucose and hemoglobin A1c levels were significantly higher in patients with cortical involvement of a recent infarct contralateral to their focal seizures than in those with infarcts in other regions. Conclusion These findings suggest that recent infarcts play a role as systemic causes of acute symptomatic seizures as well as an epileptogenic lesion in ischemic stroke patients with early focal seizures.

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.

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.

Incidence rate and risk factors of status epilepticus after stroke

Purpose To evaluate the incidence rate and risk factors for status epilepticus (SE) after stroke (PSSE), including ischaemic stroke (IS), intracerebral hemorrhage (ICH), and subarachnoid hemorrhage (SAH). Methods A meta-analysis was performed using relevant research from databases such as PubMed, Embase, Cochrane Online Library, and Clinicaltrials.gov. The quality of the studies was evaluated by using the quality evaluation criteria of the Agency for Healthcare Research and Quality (AHRQ). All data were pooled by STATA 12.0 software for meta-analysis. Results The review considered 1650 articles, and 17 articles with 2821 instances of SE among 1088087 instances of stroke were included. The incidence rate of SE after stroke was 6.90 per 1000 total strokes (95% CI: 5.58-8.22). By subgroup analysis of SE, the rates were 33.85‰ (95% CI: 13.77-53.94) for non-convulsive status epilepticus (NCSE) and 2.42‰ (95%CI: 1.66-3.19) for generalized convulsive status epilepticus (GCSE). Age, sex, and presence of atrial fibrillation showed no significant difference between the SE group and the non-SE group after stroke. Hypertension and diabetes are associated with a decreased rate of SE. However, African American race, alcohol abuse, and renal disease are associated with an increased rate of SE. Significance There were approximately 6.9 patients with status epilepticus per 1000 strokes. NCSE is more common after stroke and needs more attention. African American race, alcohol abuse and renal disease may be risk factors for PSSE.

Risk factors for early-onset seizures after stroke: A systematicreview and meta-analysis of 18 observational studies

OBJECTIVES

To systematically evaluate the risk factors of early-onset seizures after stroke, in order to better provide evidence-based results for early detection, identification, targeted prevention, and treatment of this disease.

METHODS

PubMed, EMBASE, The Cochrane Library, CNKI, and WanFang databases were searched to collect relevant studies on the risk factors of early-onset seizures after stroke from January 2010 to January 2020. Meta-analysis of all included studies was performed by using RevMan version 5.3 and Stata version 14.0 software.

RESULTS

Eighteen case-control studies with a total sample size of 13,289 cases, including 813 cases with early-onset seizures after stroke, and 12,476 cases with non-early-onset seizures after stroke were included. The results of meta-analysis showed that cortical involvement [Odds Ratio (OR) = 5.00, 95%Confidence Interval (CI) (2.85, 8.74), p < .00001], cerebral infarction with hemorrhagic transformation [OR = 2.77, 95%CI (1.87, 4.11), p < .00001] and intracerebral hemorrhage [OR = 1.83, 95%CI (1.13, 2.97), p = .01]-related factors showed greater association with the occurrence of early-onset seizures after stroke.

CONCLUSIONS

These findings suggest that cortical involvement, intracerebral hemorrhage, and cerebral infarction with hemorrhagic transformation are important predictors and risk factors for early seizures after stroke, while the patient's gender, age, NHISS score, alcoholism, smoking, high blood pressure, diabetes, atrial fibrillation, dyslipidemia, receiving surgical treatment, and reperfusion therapy showed no association with the occurrence of early-onset seizures after stroke.

New-onset seizures after cranioplasty-a different view on a putatively frequently observed phenomenon

Background

New-onset seizures after cranioplasty (NOSAC) are reported to be a frequent complication of cranioplasty (CP) after decompressive hemicraniectomy (DHC). There are considerable differences in the incidence of NOSAC and contradictory data about presumed risk factors in the literature. We suggest NOSAC to be a consequence of patients’ initial condition which led to DHC, rather than a complication of subsequent CP. We conducted a retrospective analysis to verify our hypothesis.

Methods

The medical records of all patients ≥ 18 years who underwent CP between 2002 and 2017 at our institution were evaluated including incidence of seizures, time of seizure onset, and presumed risk factors. Indication for DHC, type of implant used, timing of CP, patient age, presence of a ventriculoperitoneal shunt (VP shunt), and postoperative complications were compared between patients with and without NOSAC.

Results

A total of 302 patients underwent CP between 2002 and 2017, 276 of whom were included in the outcome analysis and the incidence of NOSAC was 23.2%. Although time between DHC and CP differed significantly between DHC indication groups, time between DHC and seizure onset did not differ, suggesting the occurrence of seizures to be independent of the procedure of CP. Time of follow-up was the only factor associated with the occurrence of NOSAC.

Conclusion

New-onset seizures may be a consequence of the initial condition leading to DHC rather than of CP itself. Time of follow-up seems to play a major role in detection of new-onset seizures.

Treatment with Diazepam in Acute Stroke Prevents Poststroke Seizures: A Substudy of the EGASIS Trial

OBJECTIVE

The frequency of seizures after stroke is high, with a severe impact on the quality of life. However, little is known about their prevention. Therefore, we investigated whether early administration of diazepam prevents the development of seizures in acute stroke patients.

METHODS

We performed a substudy of the EGASIS trial, a multicenter double-blind, randomized trial in which acute stroke patients were treated with diazepam or placebo for 3 days. Follow-up was after 2 weeks and 3 months. The occurrence of seizures was registered prospectively as one of the prespecified secondary outcomes.

RESULTS

784 EGASIS patients were eligible for this substudy (389 treated with diazepam [49.6%] and 395 treated with placebo [50.4%]). Seizures were reported in 19 patients (2.4% of the total patient group). Seizures occurred less frequently in patients treated with diazepam (1.5 vs. 3.3% in the placebo group); however, this difference was only statistically significant in patients with a cortical anterior circulation infarction (0.9% in the diazepam group vs. 4.6% in the placebo group, incidence rate ratio 0.20, 95% CI: 0.05-0.78, p = 0.02, NNT = 27).

CONCLUSION

We found that a 3-day treatment with diazepam after acute cortical anterior circulation stroke prevents the occurrence of seizures in the first 3 months following stroke.

Antiepileptic Drug Management in Acute Ischemic Stroke: Are Vascular Neurologists Utilizing Electroencephalograms? An Observational Cohort Study

Introduction

This study examines the utility of electroencephalography (EEG) in clinical decision making in acute ischemic stroke (AIS) patients in regards to the prescription of antiseizure medications.

Methods

Patients were grouped as having positive EEG (+) for epileptiform activity or negative EEG (-). These studies were no more than 30 minutes in length. Patients' charts were retrospectively reviewed for antiepileptic drug (AED) use before, during, and on discharge from AIS hospitalization.

Results

Of the 509 patients meeting inclusion criteria, 24 (4.7%) had a positive EEG. Patients did not significantly differ with respect to any demographic or baseline characteristics with the exception of prior history of seizure. In the EEG- group, AEDs were discontinued in only 3.5% of patients. In the EEG+ group, only 37.5% of patients had an initiation or change to their AED regimen within 36 hours of the study. 62.5% of the EEG+ group had a cortical stroke. Significance. Our results indicate that vascular neurologists are not using spot EEGs to routinely guide inpatient AED management. EEGs may have greater utility in those with a prior history of seizures and cortical strokes. Longer or continuous EEG monitoring may have better utility in the AIS population if there is clinical suspicion of seizure.

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.

Statins in primary prevention of poststroke seizures and epilepsy: A systematic review

INTRODUCTION

Cerebrovascular disease is the most common cause of seizures in adults and the elderly. So far, no drug is recommended as primary prevention of acute symptomatic poststroke seizures (ASPSS) or poststroke epilepsy (PSE). This systematic review aimed to evaluate the association between the use of statins after stroke and the risk of developing ASPSS or PSE following cerebral infarct or hemorrhage (primary prevention).

METHODS

We included studies evaluating the poststroke use of statins as primary prevention of ASPSS or PSE, irrespective of stroke type. We excluded uncontrolled studies and studies with prestroke statin use. The main outcome included the occurrence of ASPSS or PSE and the effect of statins by type and dose. The odds ratios (ORs) or hazard ratios (HR) with 95% confidence intervals (CIs) were used as the measures of association between treatment and outcome.

RESULTS

Four studies were included. One study showed a reduced risk of ASPSS after ischemic stroke (OR: 0.25; 95% CI: 0.10-0.59; p = 0.0016). Three studies consistently reported a reduced risk of PSE after ischemic stroke, and one study a reduced risk of PSE after hemorrhagic stroke (HR: 0.62; 95% CI: 0.42-0.90; p = 0.01).

CONCLUSIONS

Data from the literature suggest an association between statin use and a reduced risk of ASPSS after ischemic stroke and a reduced risk of PSE after ischemic and hemorrhagic stroke. Although the certainty of the evidence is low, these findings appear promising and worthy of further investigation.

Correlation of blood biomarkers with early-onset seizures after an acute stroke event

INTRODUCTION

Blood biomarkers have not been widely studied in stroke-related seizures. In this study, we aimed to describe clinical factors and biomarkers present during acute stroke and to analyze their association with early-onset seizures.

METHODS

We retrospectively evaluated a panel of 14 blood biomarkers in 1115 patients with ischemic and hemorrhagic stroke. Biomarkers were normalized and standardized using Z scores. We also recorded stroke and epilepsy-related variables, including stroke severity (National Institute of Health Stroke Scale [NIHSS] scores), type, and causes, time from onset of stroke to occurrence of early seizures, and type of seizure. Adjusted logistic regression models were built to identify clinical variables and biomarkers independently associated with early seizures.

RESULTS

Mean ± standard deviation (SD) age was 72.3 ± 13.2 years, and 56.8% of the patients were men. Thirty-eight patients (3.9%) developed early seizures with a median time to onset of 1 day (interquartile range (IQR), 0-4). A higher NIHSS score (odds ratio [OR] = 1.046; 95% confidence interval (CI): 1.001-1.094; p = 0.044) and hemorrhagic stroke (OR = 2.133; 95% CI: 1.010-4.504; p = 0.047) were independently associated with a greater risk of early seizures. Independent blood biomarkers predictive of early seizures were lower levels of tumor necrosis factor receptor 1 (TNF-R1) (<0.013) (p = 0.006; OR = 3.334; 95% CI: 1.414-7.864) and higher levels of neural cell adhesion molecule (NCAM) (>0.326) (p = 0.009; OR = 2.625; 95% CI: 1.271-5.420). The predictive power of the regression model was greater when clinical variables were combined with blood biomarkers (73.5%; 95% CI: 65.1%-81.9%) than when used alone (64%; 95% CI: 55%-72.9%).

CONCLUSION

Higher NCAM and lower TNF-R1 levels may help predict the occurrence of early seizures. The combined use of these biomarkers and clinical variables could be useful for identifying patients at risk of seizures. This article is part of the Special Issue "Seizures & Stroke".

Statin treatment can reduce incidence of early seizure in acute ischemic stroke: A propensity score analysis

A previous study showed early statin administration in patients with acute ischemic stroke (AIS) was associated with a lower risk of early-onset seizure (ES), which is a high risk of epilepsy, but this retrospective study design may not have eliminated confounding factor effects. We aimed to verify the determinants and prognostic significance of ES and clarify the effects of statin administration. Consecutive AIS patients without a history of epilepsy were enrolled. The relationship between ES (within 7 days of index-stroke) and statin treatment was assessed using multivariate and propensity scores (PS). Of 2,969 patients with AIS, 1,623 (54.6%) were treated with statin, and 66 (2.2%) developed ES. In logistic regression models, cortical stroke lesion [odds ratio (OR), 2.82; 95% confidence interval (CI), 1.29–7.28) and pre-morbid modified Rankin Scale (per 1 point) (OR, 1.39; 95% CI, 1.18–1.65) were higher risks for ES, while statin significantly reduced the risk of ES (OR, 0.44; 95% CI, 0.24–0.79). In accordance with PS-matching, statin treatment produced consistent results for ES after adjusting by inverse probability of treatment-weighting PS (OR, 0.41; 95% CI, 0.22–0.75). In conclusion, as previously, statin treatment was independently associated with a lower risk of ES in AIS.

Early seizures after ischemic stroke: focus on thrombolysis

INTRODUCTION

Stroke is a significant underlying cause of epilepsy. Seizures due to ischemic stroke (IS) are generally categorized into early seizures (ESs) and late seizures (LSs). Seizures in thrombolysis situations may raise the possibility of other etiology than IS.

AIM

We overtook a systematic review focusing on the pathogenesis, prevalence, risk factors, detection, management, and clinical outcome of ESs in IS and in stroke/thrombolysis situations. We also collected articles focusing on the association of recombinant tissue-type plasminogen activator (rt-PA) treatment and epileptic seizures.

RESULTS

We have identified 37 studies with 36,775 participants. ES rate was 3.8% overall in patients with IS with geographical differences. Cortical involvement, severe stroke, hemorrhagic transformation, age (<65 years), large lesion, and atrial fibrillation were the most important risk factors. Sixty-one percent of ESs were partial and 39% were general. Status epilepticus (SE) occurred in 16.3%. 73.6% had an onset within 24 h and 40% may present at the onset of stroke syndrome. Based on EEG findings seizure-like activity could be detected only in approximately 18% of ES patients. MRI diffusion-weighted imaging and multimodal brain imaging may help in the differentiation of ischemia vs. seizure. There are no specific recommendations with regard to the treatment of ES.

CONCLUSION

ESs are rare complications of acute stroke with substantial burden. A significant proportion can be presented at the onset of stroke requiring an extensive diagnostic workup.

Epilepsy in the elderly: Unique challenges in an increasingly prevalent population

Elderly individuals (aged at least 60 or 65 years) represent a rapidly growing segment of the population. The incidence and prevalence of epilepsy is higher in this age group than in any other. Diagnosing epilepsy in the elderly can be challenging because the causes and clinical manifestations of seizures often differ as compared with younger individuals. Particular differential diagnoses, such as syncope and amyloid spells, are commonly encountered in the elderly population. A diagnosis of epilepsy has important implications in the older adult, many of which already present a variety of concomitant complex medical problems, such as cognitive impairment, comorbid cerebrovascular disease, and frailty. The treatment of epilepsy in the elderly is complicated by a variety of factors related to aging, including physiological changes, medical comorbidities, and polypharmacy. In this narrative review, we will address the descriptive epidemiology, clinical presentation, differential diagnosis, diagnostic evaluation, treatment, and prognosis of epilepsy in the elderly individual.

Seizures Do Not Affect Disability and Mortality Outcomes of Stroke: A Population-Based Study

Although seizures are frequently seen after cerebrovascular accidents, their effects on long-term outcome in stroke patients are still unknown. Therefore, the aim of this study was to investigate the relationship between post-stroke seizures and the risk of long-term disability and mortality in stroke patients. This study is part of a larger population-based study. All patients were prospectively followed up by a face-to-face interview or a structured telephone interview. We enrolled 635 patients with first-ever stroke and without a history of seizures. Prevalence of ischemic stroke (IS) was 85.2%, while the remaining 14.8% of patients were affected by intracerebral hemorrhage (ICH). During the study period, 51 subjects (8%) developed post-stroke seizures. Patients with post-stroke seizures were younger, had a higher prevalence of ICH, had a more severe stroke at admission, were more likely to have an IS involving the total anterior circulation, and were more likely to have a lobar ICH than patients without seizures. Moreover, subjects with seizures had more frequently hemorrhagic transformation after IS and cortical strokes. At 24 months, the risk of disability in patients with seizures was almost twice than in those without seizures. However, the negative effect of seizures disappeared in multivariate analysis. Kaplan-Meier survival curves at 12 years were not significantly different between patients with and without post-stroke seizures. Using the Cox multivariate analysis, age, NIHSS at admission, and pre-stroke mRS were independently associated with all-cause long-term mortality. In our sample, seizures did not impair long-term outcome in patients affected by cerebrovascular accidents. The not significant, slight difference in favor of a better survival for patients with seizures may be attributed to the slight age difference between the two groups.

Intravenous thrombolysis for suspected ischemic stroke with seizure at onset

OBJECTIVE

Seizure at onset (SaO) has been considered a relative contraindication for intravenous thrombolysis (IVT) in patients with acute ischemic stroke, although this appraisal is not evidence based. Here, we investigated the prognostic significance of SaO in patients treated with IVT for suspected ischemic stroke.

METHODS

In this multicenter, IVT-registry-based study we assessed the association between SaO and symptomatic intracranial hemorrhage (sICH, European Cooperative Acute Stroke Study II definition), 3-month mortality, and 3-month functional outcome on the modified Rankin Scale (mRS) using unadjusted and adjusted logistic regression, coarsened exact matching, and inverse probability weighted analyses.

RESULTS

Among 10,074 IVT-treated patients, 146 (1.5%) had SaO. SaO patients had significantly higher National Institutes of Health Stroke Scale score and glucose on admission, and more often female sex, prior stroke, and prior functional dependence than non-SaO patients. In unadjusted analysis, they had generally less favorable outcomes. After controlling for confounders in adjusted, matched, and weighted analyses, all associations between SaO and any of the outcomes disappeared, including sICH (odds ratio [OR]_unadjusted = 1.53 [95% confidence interval (CI) = 0.74-3.14], OR_adjusted = 0.52 [95% CI = 0.13-2.16], OR_matched = 0.68 [95% CI = 0.15-3.03], OR_weighted = 0.95 [95% CI = 0.39-2.32]), mortality (OR_unadjusted = 1.49 [95% CI = 1.00-2.24], OR_adjusted = 0.98 [95% CI = 0.5-1.92], OR_matched = 1.13 [95% CI = 0.55-2.33], OR_weighted = 1.17 [95% CI = 0.73-1.88]), and functional outcome (mRS ≥ 3/ordinal mRS: OR_unadjusted = 1.33 [95% CI = 0.96-1.84]/1.35 [95% CI = 1.01-1.81], OR_adjusted = 0.78 [95% CI = 0.45-1.32]/0.78 [95% CI = 0.52-1.16], OR_matched = 0.75 [95% CI = 0.43-1.32]/0.45 [95% CI = 0.10-2.06], OR_weighted = 0.87 [95% CI = 0.57-1.34]/1.00 [95% CI = 0.66-1.52]). These results were consistent regardless of whether patients had an eventual diagnosis of ischemic stroke (89/146) or stroke mimic (57/146 SaO patients).

INTERPRETATION

SaO was not an independent predictor of poor prognosis. Withholding IVT from patients with assumed ischemic stroke presenting with SaO seems unjustified. ANN NEUROL 2019;86:770-779.

Hypertension, seizures, and epilepsy: a review on pathophysiology and management

BACKGROUND

Epilepsy and hypertension are common chronic conditions, both showing high prevalence in older age groups. This review outlines current experimental and clinical evidence on both direct and indirect role of hypertension in epileptogenesis and discusses the principles of drug treatment in patients with hypertension and epilepsy.

METHODS

We selected English-written articles on epilepsy, hypertension, stroke, and cerebrovascular disease until December, 2018.

RESULTS

Renin-angiotensin system might play a central role in the direct interaction between hypertension and epilepsy, but other mechanisms may be contemplated. Large-artery stroke, small vessel disease and posterior reversible leukoencephalopathy syndrome are hypertension-related brain lesions able to determine epilepsy by indirect mechanisms. The role of hypertension as an independent risk factor for post-stroke epilepsy has not been demonstrated. The role of hypertension-related small vessel disease in adult-onset epilepsy has been demonstrated. Posterior reversible encephalopathy syndrome is an acute condition, often caused by a hypertensive crisis, associated with the occurrence of acute symptomatic seizures. Chronic antiepileptic treatment should consider the risk of drug-drug interactions with antihypertensives.

CONCLUSIONS

Current evidence from preclinical and clinical studies supports the vision that hypertension may be a cause of seizures and epilepsy through direct or indirect mechanisms. In both post-stroke epilepsy and small vessel disease-associated epilepsy, chronic antiepileptic treatment is recommended. In posterior reversible encephalopathy syndrome blood pressure must be rapidly lowered and prompt antiepileptic treatment should be initiated.

[Epileptic seizures and epilepsy after a stroke : Incidence, prevention and treatment]

Following stroke, 3-6% of patients develop acute symptomatic seizures within the first 7 days. The rate is higher after cerebral haemorrhage compared to ischaemia. In 10-12% of patients, after more than 7 days unprovoked seizures occur. Due to these low incidence rates, primary prophylaxis with antiepileptic drugs is generally not necessary. Following one acute symptomatic seizure, recurrence risk within the first 7 days post-stroke is 10-20%, generally arguing against secondary prophylaxis with an antiepileptic drug. In clinical practice however, antiepileptic drug treatment in this constellation is often initiated. If this is done, the antiepileptic drug should be withdrawn soon after the acute phase, as the long-term risk for manifestation of an unprovoked seizure is approximately 30%. Following one post-stroke unprovoked seizure, recurrence risk within the next 10 years is more than 70%, this defines epilepsy. In this case, antiepileptic drug treatment is regularly recommended.

Incidence, predictors, and outcome of early seizures after mechanical thrombectomy

OBJECTIVE

Despite the wide utilization of mechanical thrombectomy (MT) for acute ischemic stroke treatment, little is known about the incidence of early post-thrombectomy seizures, its predictors, and association with long-term outcome.

METHODS

Using a prospective registry of mechanical thrombectomy in ischemic stroke between January 2013 and July 2017, we identified patients who developed a seizure within 7 days (early seizure) of qualifying event. Backward stepwise regression analysis was used to assess independent predictors of seizure occurrence and the association between seizure and functional outcome (modified Rankin scale of 0-2 vs. ≥3).

RESULTS

A total of 459 patients were included in the final analysis. Mean age was 67.5 (SD 15.1), and 49.9% of patients were female. Successful recanalization (TICI≥2B) was achieved in 92.8% of patients. Eleven (2.4%) patients developed at least one seizure. Only an Alberta Stroke Program Early CT (ASPECT) score of <6 was independently associated with the occurrence of early seizures [Odds ratio, 95% confidence interval: 8.188, (2.219-30.214); P = .002]. On multivariate analysis, early seizures were associated with 90-day mortality rate [OR,6.487; 95% confidence interval, (1.481-28.405); P = .013] and poor functional outcome (OR, 4.7; 95% confidence interval (1.08-20.83); p = .039).

CONCLUSION

In the studied cohort, 2.4% of ischemic stroke patients treated with MT developed at least one seizure within 7 days of stroke onset. A low ASPECT score was associated with the occurrence of early seizures. The occurrence of seizures was associated with 90-day mortality and poor functional outcome.

Neuro-Immune Hemostasis: Homeostasis and Diseases in the Central Nervous System

Coagulation and the immune system interact in several physiological and pathological conditions, including tissue repair, host defense, and homeostatic maintenance. This network plays a key role in diseases of the central nervous system (CNS) by involving several cells (CNS resident cells, platelets, endothelium, and leukocytes) and molecular pathways (protease activity, complement factors, platelet granule content). Endothelial damage prompts platelet activation and the coagulation cascade as the first physiological step to support the rescue of damaged tissues, a flawed rescuing system ultimately producing neuroinflammation. Leukocytes, platelets, and endothelial cells are sensitive to the damage and indeed can release or respond to chemokines and cytokines (platelet factor 4, CXCL4, TNF, interleukins), and growth factors (including platelet-derived growth factor, vascular endothelial growth factor, and brain-derived neurotrophic factor) with platelet activation, change in capillary permeability, migration or differentiation of leukocytes. Thrombin, plasmin, activated complement factors and matrix metalloproteinase-1 (MMP-1), furthermore, activate intracellular transduction through complement or protease-activated receptors. Impairment of the neuro-immune hemostasis network induces acute or chronic CNS pathologies related to the neurovascular unit, either directly or by the systemic activation of its main steps. Neurons, glial cells (astrocytes and microglia) and the extracellular matrix play a crucial function in a “tetrapartite” synaptic model. Taking into account the neurovascular unit, in this review we thoroughly analyzed the influence of neuro-immune hemostasis on these five elements acting as a functional unit (“pentapartite” synapse) in the adaptive and maladaptive plasticity and discuss the relevance of these events in inflammatory, cerebrovascular, Alzheimer, neoplastic and psychiatric diseases. Finally, based on the solid reviewed data, we hypothesize a model of neuro-immune hemostatic network based on protein–protein interactions. In addition, we propose that, to better understand and favor the maintenance of adaptive plasticity, it would be useful to construct predictive molecular models, able to enlighten the regulating logic of the complex molecular network, which belongs to different cellular domains. A modeling approach would help to define how nodes of the network interact with basic cellular functions, such as mitochondrial metabolism, autophagy or apoptosis. It is expected that dynamic systems biology models might help to elucidate the fine structure of molecular events generated by blood coagulation and neuro-immune responses in several CNS diseases, thereby opening the way to more effective treatments.

Epilepsy after stroke: Definitions, problems and a practical approach for clinicians

Stroke, whether ischemic or hemorrhagic, is the main etiology of epilepsy in the elderly. However, incidences and outcomes differ according to stroke subtype and delay of onset following the stroke. While the medical literature is extensive, it is not always consistent, and many questions still remain regarding risk factors and management of vascular epilepsy. Thus, the present report here is an overview of the clinical aspects of vascular epilepsy using a practical approach that integrates data from meta-analyses and the more recently published expert recommendations.

Contributions of the Hippocampal CA3 Circuitry to Acute Seizures and Hyperexcitability Responses in Mouse Models of Brain Ischemia

The hippocampal circuitry is widely recognized as susceptible to ischemic injury and seizure generation. However, hippocampal contribution to acute non-convulsive seizures (NCS) in models involving middle cerebral artery occlusion (MCAO) remains to be determined. To address this, we occluded the middle cerebral artery in adult C57 black mice and monitored electroencephalographic (EEG) discharges from hippocampal and neocortical areas. Electrographic discharges in the absence of convulsive motor behaviors were observed within 90 min following occlusion of the middle cerebral artery. Hippocampal discharges were more robust than corresponding cortical discharges in all seizure events examined, and hippocampal discharges alone or with minimal cortical involvement were also observed in some seizure events. Seizure development was associated with ipsilateral hippocampal injuries as determined by subsequent histological examinations. We also introduced hypoxia-hypoglycemia episodes in mouse brain slices and examined regional hyperexcitable responses ex vivo. Extracellular recordings showed that the hippocampal CA3 region had a greater propensity for exhibiting single/multiunit activities or epileptiform field potentials following hypoxic-hypoglycemic (HH) episodes compared to the CA1, dentate gyrus, entorhinal cortical (EC) or neocortical regions. Whole-cell recordings revealed that CA3 pyramidal neurons exhibited excessive excitatory postsynaptic currents, attenuated inhibitory postsynaptic currents and intermittent or repetitive spikes in response to HH challenge. Together, these observations suggest that hippocampal discharges, possibly as a result of CA3 circuitry hyperexcitability, are a major component of acute NCS in a mouse model of MCAO.

Post-stroke seizure-Do the locations, types and managements of stroke matter?

Objective

To determine the incidence of post‐stroke seizures and the associated risk factors in a government‐restructured hospital in Singapore.

Methods

This retrospective study included consecutive patients (age ≥21 years) admitted to the stroke rehabilitation facility at Changi General Hospital, Singapore, between June 2008 and May 2017, with a minimum post‐discharge follow‐up of 6 months. Patients with known epilepsy central nervous system infection or tumor, a history of neurosurgery and or missing data were excluded from study. To determine the incidence of seizures, the patients’ hospital records, including those for all initial and subsequent admissions and outpatient follow‐ups, were reviewed. All prescribed medications were checked and documented. Seizures were diagnosed on the basis of clinical examination with or without electroencephalography.

Results

In total, 722 patients (women, 38%) with a mean age of 64 years were included. Of these, 48 (6.64%) experienced post‐stroke seizures during a follow‐up period of 6–108 months. The incidence of seizures was significantly higher in patients with hemorrhagic stroke (42%, p = 0.010), those with ischemic partial anterior circulation stroke (PACS) (27%, p = 0.025), those who underwent a neurosurgical procedure after stroke (p < 0.001), those with a low activated partial thromboplastin time (APTT) at admission (mean, 25.6; p = 0.015), and those using levodopa (21%, p < 0.001). Neurosurgical intervention after stroke (odds ratio [OR] 6.2, 95% confidence interval [CI] 2.9–13.1; p < 0.001), APTT (per‐unit increase; OR 0.86, 95% CI 0.76–0.98; p = 0.028), and underlying ischemic heart disease (IHD; OR 2.2, 95% CI 1.08–4.60; p = 0.029) were found to be independent predictors of seizure occurrence after stroke.

Significance

Post‐stroke seizure incidence from our study is 6.64%, with a median follow‐up of 49 months. Among patients with stroke, those with underlying IHD, those who undergo a neurosurgical procedure, and those with a low APTT at admission need careful monitoring. Levodopa should be used with caution and withdrawn as soon as possible.

Basilar Artery Occlusion with "Seizures" as a Presenting Symptom: Three Cases Treated Using Mechanical Thrombectomy

BACKGROUND

Basilar artery occlusion (BAO) is a rare, potentially fatal cause of ischemic stroke. It is often challenging to diagnose, especially when the presenting symptom is "seizures". We present 3 cases of patients with BAO presenting with seizures.

CASE DESCRIPTION

The first patient was a 53-year-old man with clonic convulsions. On angiography, BAO was detected and mechanical thrombectomy (MT) was performed. The modified Rankin Scale score at 3 months after treatment was 1. The second patient was a 64-year-old man with generalized convulsions. He was diagnosed with BAO and vertebral artery dissection and was treated with MT, percutaneous transluminal angioplasty, and stenting. The modified Rankin Scale score at 3 months after treatment was 3. The third patient was a 77-year-old man with tonic convulsions. He was diagnosed with BAO and treated with MT. However, he did not survive.

CONCLUSIONS

BAO is devastating; however, it is a treatable disease. Our report suggests that BAO should be suspected in patients presenting with initial convulsive seizures.

The occurrence of seizures after ischemic stroke does not influence long-term mortality; a 26-year follow-up study

Objective

Epileptic seizures are a common complication after stroke. The relation between occurrence of seizures after stroke and long-term mortality remains elusive. We aimed to assess whether seizures in an early or late phase after ischemic stroke are an independent determinant of long-term mortality.

Methods

We prospectively included and followed 444 ischemic stroke patients with a first-ever supratentorial brain infarct for at least 2 years after their stroke regarding the occurrence of seizures. The final follow-up for mortality is from April 2015 (follow-up duration 24.5–27.8 years, mean 26.0 years, SD 0.9 years). We compared patients with early-onset seizures with all seizure-free patients, whereas the patients with late-onset seizures were compared with the 1-week survivors without any seizures. We used Cox-regression analyses to correct for possible confounding factors.

Results

Kaplan–Meier analysis showed significantly higher mortality for the patients with early-onset seizures (p = 0.002) but after correction for known risk factors for (long term) mortality early-onset seizures had no independent influence on long-term mortality (HR 1.09; 95% CI 0.64–1.85). In patients with late-onset seizures, no significant influence from late-onset seizures on long-term mortality was found (univariate p = 0.717; multivariate HR 0.81; 95% CI 0.54–1.20).

Conclusion

Both early-onset and late-onset seizures do not influence long-term mortality after ischemic stroke.

Prevalence, risk factors, and impact on mortality of neuropsychiatric lupus: a prospective, single-center study

Objective The objective of this paper is to identify the prevalence, risk factors, and impact on mortality of neuropsychiatric systemic lupus erythematosus (NPSLE). Methods Patients from the Hanyang BAE lupus cohort were registered and followed from 1998 to 2015. NPSLE was defined using American College of Rheumatology (ACR) case definitions and Ainiala criteria. Demographics, autoantibodies, Systemic Lupus Erythematosus Disease Activity Index (SLEDAI), and Systemic Lupus International Collaborating Clinic (SLICC)/ACR Damage Index were collected at baseline and then annually. Mortality data were derived by linking data from the Korean National Statistics Office. Multivariable logistic regression and Cox regression analysis were conducted in the inception cohort to assess the risk factors and mortality impact of NPSLE. Results Of 1121 registered patients, 429 (38.3%) had NPSLE manifestations according to ACR criteria and 216 (19.3%) by Ainiala criteria. In multivariable logistic regression analysis, higher SLEDAI (OR 1.08, CI 1.01-1.16, p = 0.02) and antiphospholipid antibody positivity (OR 1.72, CI 1.03-2.87, p = 0.04) at SLE diagnosis increased NPSLE risk, while elevated anti-dsDNA antibodies (OR 0.43, CI 0.24-0.78, p < 0.01) and greater education duration (OR 0.92, CI 0.85-1.00, p = 0.04) showed reduced risk of NPSLE. Cox proportional hazard models demonstrated that presence of NPSLE had a three-fold increased risk of mortality (HR 3.09, CI 1.03-9.21, p = 0.04), especially in patients with focal CNS NPSLE (HR = 7.83, CI 2.12-28.96, p < 0.01). Conclusion Higher SLEDAI, antiphospholipid antibody positivity, absence of anti-dsDNA antibody at SLE diagnosis, and fewer years of education are risk factors for development of NPSLE. Presence of NPSLE, especially focal CNS NPSLE, increased the risk of mortality in SLE patients.

Small Hyperintensities in the Area of the Perforating Arteries in Patients with Seizure

Background/Aim: We previously observed spotty hyperintense lesions in the region of the perforating arteries on peri-ictal diffusion-weighted imaging (DWI); however, no report has formally described these findings. The aim of this study was to investigate focal intensities on peri-ictal DWI, and to evaluate the clinical significance of these lesions. Methods: We conducted a retrospective review of 677 consecutive patients with seizure who completed peri-ictal DWI within 24 h after seizure onset. Patients were grouped according to the presence or absence of diffusion hyperintense lesions (DHLs) in the region of the perforating arteries. We compared clinical and imaging characteristics between these 2 groups. Results: Among 677 patients, 23 patients (3.4%) had DHLs. Analyses of apparent diffusion coefficient values and fluid attenuated inversion recovery images suggested that DHLs were acute or subacute ischemic lesions that had appeared prior to seizure onset. Patients with DHLs were more likely to be older in age, have atrial fibrillation, and coronary artery disease, and have more severe deep white matter hyperintensity or leukoaraiosis compared to patients without DHLs. Conclusion: DHLs detected on peri-ictal DWI may represent incidental acute cerebral microinfarcts in the aging brain, especially in patients with small vessel disease.

mTOR is involved in stroke-induced seizures and the anti-seizure effect of mild hypothermia

Stroke is considered an underlying etiology of the development of seizures. Stroke leads to glucose and oxygen deficiency in neurons, resulting in brain dysfunction and injury. Mild hypothermia is a therapeutic strategy to inhibit stroke‑induced seizures, which may be associated with the regulation of energy metabolism of the brain. Mammalian target of rapamycin (mTOR) signaling and solute carrier family 2, facilitated glucose transporter member (GLUT)‑1 are critical for energy metabolism. Furthermore, mTOR overactivation and GLUT‑1 deficiency are associated with genetically acquired seizures. It has been hypothesized that mTOR and GLUT‑1 may additionally be involved in seizures elicited by stroke. The present study established global cerebral ischemia (GCI) models of rats. Convulsive seizure behaviors frequently occurred during the first and the second days following GCI, which were accompanied with seizure discharge reflected in the EEG monitor. Expression of phosphor (p)‑mTOR and GLUT‑1 were upregulated in the cerebral cortex and hippocampus, as evidenced by immunohistochemistry and western blot analyses. Mild hypothermia and/or rapamycin (mTOR inhibitor) treatments reduced the number of epileptic attacks, seizure severity scores and seizure discharges, thereby alleviating seizures induced by GCI. Mild hypothermia and/or rapamycin treatments reduced phosphorylation levels of mTOR and the downstream effecter p70S6 in neurons, and the amount of GLUT‑1 in the cytomembrane of neurons. The present study revealed that mTOR is involved in stroke‑induced seizures and the anti‑seizure effect of mild hypothermia. The role of GLUT‑1 in stroke‑elicited seizures appears to be different from the role in seizures induced by other reasons. Further studies are necessary in order to elucidate the exact function of GLUT-1 in stroke‑elicited seizures.

The Progress of Epilepsy after Stroke

BACKGROUND

Epilepsy is the second most common disease caused by multiple factors and characterized by an excessive discharge of certain neurons in the nervous system. Cerebrovascular disease, including stroke, is viewed as the most common cause of epilepsy in the elderly population, accounting for 30%-50% of the newly diagnosed cases of epilepsy cases in this age group.

METHODS

Data were collected from Web of Science, Medline, Pubmed, Scopus, through searching of these keywords: "Stroke" and "epilepsy".

RESULTS

Depending on the underlying cerebrovascular disease, 3%-30% of patients after stroke may develop post-stroke epilepsy (PSE), which has a negative effect on stroke prognosis and the quality of life.

CONCLUSION

In this review, we summarized new aspects emerging from research into PSE, including definition, epidemiology, risk factors, mechanism, accessory examination and treatment strategies for post-stroke epilepsy, which will enrich our knowledge of this disorder.

Neuro-Coagulopathy: Blood Coagulation Factors in Central Nervous System Diseases

Blood coagulation factors and other proteins, with modulatory effects or modulated by the coagulation cascade have been reported to affect the pathophysiology of the central nervous system (CNS). The protease-activated receptors (PARs) pathway can be considered the central hub of this regulatory network, mainly through thrombin or activated protein C (aPC). These proteins, in fact, showed peculiar properties, being able to interfere with synaptic homeostasis other than coagulation itself. These specific functions modulate neuronal networks, acting both on resident (neurons, astrocytes, and microglia) as well as circulating immune system cells and the extracellular matrix. The pleiotropy of these effects is produced through different receptors, expressed in various cell types, in a dose- and time-dependent pattern. We reviewed how these pathways may be involved in neurodegenerative diseases (amyotrophic lateral sclerosis, Alzheimer's and Parkinson's diseases), multiple sclerosis, ischemic stroke and post-ischemic epilepsy, CNS cancer, addiction, and mental health. These data open up a new path for the potential therapeutic use of the agonist/antagonist of these proteins in the management of several central nervous system diseases.

A Systematic Appraisal of Neurosurgical Seizure Prophylaxis: Guidance for Critical Care Management

Clinical decisions are often made in the presence of some uncertainty. Health care should be based on a combination of scientific evidence, clinical experience, economics, patient value judgments, and preferences. Seizures are not uncommon following brain injury, surgical trauma, hemorrhage, altered brain metabolism, hypoxia, or ischemic events. The impact of seizures in the immediate aftermath of injury may be a prolonged intensive care stay or compounding of the primary injury. The aim of brain injury management is to limit the consequences of the secondary damage. The original intention of seizure prophylaxis was to limit the incidence of early-onset seizures. However, clinical trials have been equivocal on this point, and there is concern about the adverse effects of antiepileptic drug therapy. This review of the literature raises concerns regarding the arbitrary division of seizures into early onset (7 d) and late onset (8 d and beyond). In many cases it would appear that seizures present within 24 hours of the injury or after 7 days, which would be outside of the scope of current seizure prophylaxis guidance. There also does not appear to be a pathophysiological reason to divide brain injury-related seizures into these timeframes. Therefore, a solution to the conundrum is to reevaluate current practice. Prophylaxis could be offered to those receiving intensive care for the primary brain injury, where the impact of seizure would be detrimental to the management of the brain injury, or other clinical judgments where prophylaxis is prudent. Neurosurgical seizure management can then focus attention on which agent has the best adverse effect profile and the duration of therapy. The evidence seems to support levetiracetam as the most appropriate agent. Although previous reviews have identified an increase cost associated with the use of levetiracetam, current cost comparisons with phenytoin demonstrate a marginal price differential. The aim of this review is to assimilate the applicable literature regarding seizure prophylaxis. The final guidance is a forum upon which further clinical research could evaluate a new seizure prophylaxis paradigm.

European Stroke Organisation guidelines for the management of post-stroke seizures and epilepsy

Background

Following stroke, acute symptomatic seizures (manifestation within seven days) and epilepsy, i.e. occurrence of at least one unprovoked seizure (manifestation after more than seven days), are reported in 3-6% and up to 12% of patients, respectively. Incidence of acute symptomatic seizures is higher in intracranial haemorrhage (10-16%) than in ischaemic stroke (2-4%). Acute symptomatic seizures and unprovoked seizure may be associated with unfavourable functional outcome and increased mortality. In view of the clinical relevance, the European Stroke Organisation has issued evidence-based guidelines on the management of post-stroke seizures and epilepsy.

Method

A writing committee of six clinicians and researchers from five European countries and Israel identified seven questions relating to prevention of (further) post-stroke seizures and epilepsy and to amelioration of functional outcome and prevention of mortality. Recommendations are based on findings in randomised controlled trials and observational studies using the grading of recommendations assessment, development and evaluation approach.

Results

In the absence of adequately powered randomised controlled trials, evidence for all recommendations is very low. Based on findings in observational studies, some weak recommendations have been made. In most instances, we suggest not to administer antiepileptic drugs. Due to high incidence of seizure recurrence after one post-stroke unprovoked seizure, secondary antiepileptic drugs prophylaxis needs to be considered.

Conclusion

Due to very low evidence, these guidelines only give some weak recommendations on prevention of occurrence and recurrence of post-stroke acute symptomatic seizures and unprovoked seizure. Adequately powered randomised controlled trials are required to assess interventions for post-stroke seizure management.

Factors associated with changes in exposure to anticholinergic and sedative medications in elderly hospitalized patients: multicentre longitudinal study

BACKGROUND AND PURPOSE

Elderly patients exposed to drugs with anticholinergic or sedative properties may have an increased risk of adverse events. This study aimed to assess the relationship between patient characteristics and changes of exposure to anticholinergic and sedative medications during their hospital stay.

METHODS

A multicentre longitudinal study was set up on hospitalized patients (aged ≥65 years) using at least one drug at admission. The primary outcome was change of exposure to anticholinergic and sedative drugs between admission and discharge. Sociodemographic characteristics of the patients, comorbidities, life habits and information about the hospital stay (origin of admission, reasons for hospitalization) were collected.

RESULTS

The study included 337 patients (mean age, 85.4 years) with an average hospital stay of 30.1 ± 37.5 days. The drug burden index increased during the hospital stay among males (P = 0.03), patients for whom the reason for hospitalization was either a stroke (P = 0.001) or inability to stay in their own home (P = 0.001), and patients with diabetes mellitus (P = 0.009). In the adjusted model, drug burden index increased among patients hospitalized for stroke, inability to stay in their own home or post-surgery, and for patients with diabetes mellitus or hypertension.

CONCLUSIONS

The drug management of elderly patients during hospital stays may increase exposure to anticholinergic and sedative drugs. Although the anticholinergic and sedative properties may be in relation to the therapeutic purpose, they also represent an unexpected risk. Physicians and clinical pharmacists should consider performing optimization of the drug prescriptions for patients at risk.

Association between seizures after ischemic stroke and stroke outcome: A systematic review and meta-analysis

A systematic review and meta-analysis were performed to investigate a potential association between post-ischemic stroke seizures (PISS) and subsequent ischemic stroke (IS) outcome.A systematic search of two electronic databases (Medline and Embase) was conducted to identify studies that explored an association between PISS and IS outcome. The primary and secondary IS outcomes of interest were mortality and disability, respectively, with the latter defined as a score of 3 to 5 on the modified Rankin Scale.A total of 15 studies that were published between 1998 and 2015 with 926,492 participants were examined. The overall mortality rates for the patients with and without PISS were 34% (95% confidence interval [CI], 27-42%) and 18% (95% CI, 12-23%), respectively. The pooled relative ratio (RR) of mortality for the patients with PISS was 1.97 (95% CI, 1.48-2.61; I = 88.6%). The overall prevalence rates of disability in the patients with and without PISS were 60% (95% CI, 32-87%) and 41% (95% CI, 25-57%), respectively. Finally, the pooled RR of disability for the patients with PISS was 1.64 (95% CI, 1.32-2.02; I = 66.1%).PISS are significantly associated with higher risks of both mortality and disability. PISS indicate poorer prognoses in patients experiencing IS.

Poststroke epilepsy: update and future directions

Stroke is among the most common causes of epilepsy after middle age. Patients with poststroke epilepsy (PSE) differ in several respects from patients with other forms of structural-metabolic epilepsy; not least in age, age-related sensitivity to side effects of antiepileptic drugs (AEDs), and specific drug-drug interaction issues related to secondary-stroke prophylaxis. Encouragingly, there has lately been remarkable activity in the study of PSE. Three developments in PSE research deserve particular focus. First, large prospective trials have established the incidence and risk factors of PSE in the setting of modern stroke care. Stroke severity, cortical location, young age, and haemorrhage remain the most important risk factors. Second, although more studies are needed, epidemiological data indicate that the risk of PSE may be influenced, for instance, by statin treatment. Third, studies are emerging regarding the treatment and prognosis of PSE. Levetiracetam and lamotrigine may be well tolerated treatment options and seizure freedom is achieved in at least a similar proportion of patients as in other epilepsies. Furthermore, new animal models such as photothrombotic stroke gives hope of a more clear understanding of PSE epileptogenesis in the near future. In summary, PSE shows indications of maturing into an independent epilepsy research field. This review summarizes recent advances in our understanding of PSE and provides an update on management issues such as diagnosis, AED selection, and prognosis. Finally, future research challenges in the field are outlined.

Reduced expression of IA channels is associated with post-ischemic seizures

PURPOSE

Post-stroke seizures are considered as a major cause of epilepsy in adults. The pathophysiologic mechanisms resulting in post-stroke seizures are not fully understood. The present study attempted to reveal a new mechanism underlying neuronal hyperexcitability responsible to the seizure development after ischemic stroke.

METHODS

Transient global ischemia was produced in adult Wistar rats using the 4-vessel occlusion (4-VO) method. The spontaneous behavioral seizures were defined by the Racine scale III-V. The neuronal death in the brain was determined by hematoxylin-eosin staining. The expression levels of A-type potassium channels were analyzed by immunohistochemical staining and western blotting.

RESULTS

We found that the incidence of spontaneous behavioral seizures increased according to the severity of ischemia with 0% after 15-min ischemia and ∼50% after 25-min ischemia. All behavioral seizures occurred with 48h after ischemia. Morphological analysis indicated that brain damage was not correlated with behavioral seizures. Immunohistochemical staining showed that the expression levels of the A-type potassium channel subunit Kv4.2 was significantly reduced in ischemic brains with behavioral seizures, but not in ischemic brains without seizures. In addition, rats failing to develop spontaneous behavioral seizures within 2days after ischemia were more sensitive to bicuculline-induced seizures at 2 months after ischemia than control rats. Meanwhile, Kv4.2 expression was decreased in brain at 2 months after ischemia.

CONCLUSION

Our results demonstrated the reduction of Kv4.2 expression might contribute to the development of post-ischemic seizures and long-term increased seizure susceptibility after ischemia. The mechanisms underlying post-stroke seizures and epilepsy is unknown so far. The down-regulation of IA channels may explained the abnormal neuronal hyperexcitability responsible for the seizure development after ischemic stroke.

Wnt/β-catenin signaling mediates the seizure-facilitating effect of postischemic reactive astrocytes after pentylenetetrazole-kindling

Ischemia not only leads to tissue damage, but also induces seizures, which in turn worsens the outcome of ischemia. Recent studies have revealed the impaired homeostatic functions of reactive astrocytes, which were thought to facilitate the development of seizures. However, how this phenotype of reactive astrocytes is regulated remains unclear. Here, using pentylenetetrazole (PTZ)-kindling model, we investigated the roles of reactive astrocytes and their intracellular Wnt/β-catenin signaling in the ischemia-increased seizure susceptibility. Our data showed that somatosensory cortical ischemia significantly increased the susceptibility to PTZ-induced seizure. Genetic ablation of Nestin-positive reactive astrocytes significantly decreased the incidence and severity of seizures. By using a Wnt signaling reporter mice line Topgal mice, we found that Wnt/β-catenin signaling was upregulated in reactive astrocytes after ischemia. Depletion of β-catenin in reactive astrocytes significantly decreased the susceptibility of seizures and the expression of c-Fos induced by PTZ in the ischemic cortex. Overexpression of β-catenin in reactive astrocytes, in contrast, significantly increased seizure susceptibility and the expression of c-Fos. Furthermore, the expression of aquaporin-4 (AQP-4) and inwardly rectifying K(+) channel 4.1 (Kir4.1), two molecules reportedly associated with seizure development, was oppositely affected in reactive astrocytes with β-catenin depletion or overexpression. Taken together, these data indicated that astrocytic Wnt/β-catenin signaling accounts, at least partially, for the ischemia-increased seizure susceptibility. Inhibiting Wnt/β-catenin signaling may be utilized in the future for preventing postischemic seizures.