Association between different acute stroke therapies and development of post stroke seizures

Frequency and predictors of poststroke epilepsy after mechanical thrombectomy for large vessel occlusion stroke: results from a multicenter cohort study

BACKGROUND

Poststroke epilepsy (PSE) represents an important complication of stroke. Data regarding the frequency and predictors of PSE in patients with large-vessel occlusion stroke receiving mechanical thrombectomy (MT) are scarce. Furthermore, information on acute and preexisting lesion characteristics on brain MRI has not yet been systematically considered in risk prediction of PSE. This study thus aims to assess PSE risk after acute ischemic stroke treated with MT, based on clinical and MRI features.

METHODS

In this multicenter study from two tertiary stroke centers, we included consecutive acute ischemic stroke patients who had received MT for acute intracranial large vessel occlusion (LVO) between 2011 and 2017, in whom post-interventional brain MRI and long term-follow-up data were available. Infarct size, affected cerebrovascular territory, hemorrhagic complications and chronic cerebrovascular disease features were assessed on MRI (blinded to clinical information). The primary outcome was the occurrence of PSE (> 7 days after stroke onset) assessed by systematic follow-up via phone interview or electronic records.

RESULTS

Our final study cohort comprised 348 thrombectomy patients (median age: 67 years, 45% women) with a median long-term follow-up of 78 months (range 0-125). 32 patients (9%) developed PSE after a median of 477 days (range 9-2577 days). In univariable analyses, larger postinterventional infarct size, infarct location in the parietal, frontal or temporal lobes and cerebral microbleeds were associated with PSE. Multivariable Cox regression analysis confirmed larger infarct size (HR 3.49; 95% CI 1.67-7.30) and presence of cerebral microbleeds (HR 2.56; 95% CI 1.18-5.56) as independent predictors of PSE.

CONCLUSION

In our study, patients with large vessel occlusion stroke receiving MT had a 9% prevalence of PSE over a median follow-up period of 6.5 years. Besides larger infarct size, presence of cerebral microbleeds on brain MRI predicted PSE occurrence.

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.

Risk assessment of mechanic thrombectomy on post-stroke seizures: a systematical review and meta-analysis

PURPOSE

We conducted a systematic review and meta-analysis to evaluate the risk of early and late onset seizures following stroke mechanic thrombectomy (MT) compared with other systematic thrombolytic strategies.

METHODS

A literature search was conducted to identify articles covering databases (PubMed, Embase, and Cochrane Library) published from 2000 to 2022. The primary outcome was the incidence of post-stroke epilepsy or seizures following MT or in combination with intravenous thrombolytics therapy. Risk of bias was assessed by recording study characteristics. The study was conducted according to the PRISMA guidelines.

RESULTS

There were 1346 papers in the search results, and 13 papers were included in the final review.We identified 29,793 patients with stroke, of which 695 had seizures. Pooled incidence of post-stroke seizures had no significant difference between mechanic thrombolytic group and other thrombolytic strategy group (OR=0.95 (95%CI= 0.75-1.21); Z=0.43; p=0.67). In subgroup analysis, mechanic group have a lower risk of post-stroke early onset of seizures (OR=0.59 (95%CI=0.36-0.95); Z=2.18; p<0.05) but showed no significant difference in post-stroke late onset of seizures (OR=0.95 (95%CI= 0.68-1.32); Z=0.32; p=0.75).

CONCLUSIONS

MT may be associated with a lower risk of post-stroke early onset of seizures, despite MT does not affect the pooled incidence of post-stroke seizures compared with other systematic thrombolytic strategies.

Epileptiform activity in the acute phase of stroke predicts the outcomes in patients without seizures

Background and purpose

The abnormalities in EEG of stroke-patients increase the risk of epilepsy but their significancy for poststroke outcome is unclear. This presented study was aimed at determining the prevalence and nature of changes in EEG recordings from the stroke hemisphere and from the contralateral hemisphere. Another objective was to determine the significance of abnormalities in EEG in the first days of stroke for the post-stroke functional status on the acute and chronic phase of disease.

Methods

In all qualified stroke-patients, EEG was performed during the first 3 days of hospitalization and at discharge. The correlation between EEG abnormalities both in the stroke hemisphere and in the collateral hemisphere with the neurological and functional state in various time points was performed.

Results

One hundred thirty-one patients were enrolled to this study. Fifty-eight patients (44.27%) had abnormal EEG. The sporadic discharges and generalized rhythmic delta activity were the most common abnormalities in the EEG. The neurological status on the first day and the absence of changes in the EEG in the hemisphere without stroke were the independent factors for good neurological state (0–2 mRS) at discharge. The age-based analysis model (OR 0.981 CI 95% 0.959–1.001, p = 0.047), neurological status on day 1 (OR 0.884 CI 95% 0.82–0.942, p &lt; 0.0001) and EEG recording above the healthy hemisphere (OR 0.607 CI 95% 0.37–0.917, p = 0.028) had the highest prognostic value in terms of achieving good status 90 days after stroke.

Conclusions

Abnormalities in EEG without clinical manifestation are present in 40% of patients with acute stroke. Changes in EEG in acute stroke are associated with a poor neurological status in the first days and poor functional status in the chronic period of stroke.

Specificity and sensitivity of the SeLECT score in predicting late seizures in patients undergoing intravenous thrombolytic treatment and the effect of diabetes mellitus and leukoaraiosis

BACKGROUND

 Seizures after stroke can negatively affect the prognosis of ischemic stroke and cause a decrease in quality of life. The efficacy of intravenous (IV) recombinant tissue plasminogen activator (rt-PA) treatment in acute ischemic stroke has been demonstrated in many studies, and IV rt-PA treatment has been increasingly used around the world. The SeLECT score is a useful score for the prediction of late seizures after stroke and includes the severity of stroke (Se), large artery atherosclerosis (L), early seizure (E), cortical involvement (C), and the territory of the middle cerebral artery (T). However, the specificity and sensitivity of the SeLECT score have not been studied in acute ischemic stroke patients that received IV rt-PA treatment.

OBJECTIVE

 In the present study, we aimed to validate and develop the SeLECT score in acute ischemic stroke patients receiving IV rt-PA treatment.

METHODS

 The present study included 157 patients who received IV thrombolytic treatment in our third-stage hospital. The 1-year seizure rates of the patients were detected. SeLECT scores were calculated.

RESULTS

 In our study, we found that the SeLECT score had low sensitivity but high specificity for predicting the likelihood of late seizure after stroke in patients administered IV rt-PA therapy. In addition to the SeLECT score, we found that the specificity and sensitivity were higher when we evaluated diabetes mellitus (DM) and leukoaraiosis.

CONCLUSION

 We found that DM was an independent risk factor for late seizures after stroke in a patient group receiving thrombolytic therapy, and late seizures after stroke were less frequent in patients with leukoaraiosis.

Risk of poststroke epilepsy after reperfusion therapies: A national cohort study

BACKGROUND AND PURPOSE

The risk of poststroke epilepsy (PSE) after endovascular treatment (EVT) is not well characterized. In this nationwide study, we assessed the risk of PSE after EVT and identified associated predictors.

METHODS

We included all individuals (n = 3319) treated with EVT (±intravenous thrombolysis [IVT]) between 2015 and 2019 in the Swedish National Quality Register for EVT. Two control groups were identified from the Swedish Stroke Register: the first treated with IVT alone (n = 3132) and the second with no treatment (n = 3184), both matched for age, sex, stroke severity, and time of stroke.

RESULTS

PSE developed in 7.9% (n = 410). The survival-adjusted 2-year risk was 6.5% (95% confidence interval [CI] = 5.28-7.70) after EVT, 10.0% (95% CI = 8.25-11.75) after IVT, and 12.3% after no revascularization (95% CI = 10.33-14.25). The hazard ratio (HR) of PSE after EVT was almost half compared to no treatment (HR = 0.51, 95% CI = 0.41-0.64). The risk of PSE after EVT was lower compared to no treatment in a multivariable Cox model that adjusted for age, sex, hemicraniectomy, and stroke severity (HR = 0.76, 95% CI = 0.60-0.96). Multivariable predictors of PSE after EVT were large infarction on computed tomography Day 1, high posttreatment National Institutes of Health Stroke Scale score, and need of assistance 3 months after stroke. IVT before EVT was associated with a lower risk of PSE (HR = 0.66, 95% CI = 0.46-0.94).

CONCLUSIONS

This nationwide study identified a reduced risk of PSE after EVT. Markers of severe infarction after EVT were associated with PSE, whereas IVT given before EVT was protective.

Incidence and association of seizures in stroke patients following endovascular treatment: A systematic review and meta-analysis

BACKGROUND AND PURPOSE

Post-stroke seizures (PSSs) are some of the most common complications of stroke and are associated with poor outcomes in patients. Endovascular treatment (EVT) is the standard of care for patients with acute ischaemic stroke related large-vessel occlusion. However, whether EVT increases the risk of PSSs remains controversial; the association between PSSs and EVT is poorly understood.

METHODS

PubMed, Embase and the Cochrane Library were searched for relevant studies published from 1995 to 6 December 2021. The overall incidence of PSSs in patients treated with EVT and the separate incidence for all included studies in each subgroup, stratified by the type of treatment or time of onset, were calculated. The pooled odds ratio and confidence interval were calculated to quantify the effects of EVT on PSS occurrence.

RESULTS

In all, 946 studies were screened and 16 articles were included, with a total sample size of 12,664 patients; 7836 patients received EVT, of whom 460 had PSS. The pooled incidence of PSS after EVT was 5.8%, which was similar to patients treated with mechanical thrombectomy (5.3%), intra-arterial thrombolysis (6.8%) or bridging therapy (5.4%). The cumulative incidence of post-stroke epilepsy (6.0%) was almost twice that of acute symptomatic seizures (3.6%). The pooled odds ratio for the relationship between EVT and PSS was 1.91 (95% confidence interval 0.98-3.73).

CONCLUSIONS

The cumulative incidence of stroke patients treated with EVT who developed seizures was 5.8%, and EVT was non-significantly associated with the occurrence of seizures after stroke.

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.

Acute symptomatic seizures and status epilepticus in older adults: A narrative review focusing on management and outcomes

A clear narrative of acute symptomatic seizures (ASyS) in older adults is lacking. Older adults (≥60 years) have the highest incidence of seizures of all age groups and necessitate a tailored approach. ASyS has a bimodal peak in infancy and old age (82.3–123.2/100,000/year after 65 years of age). ASyS can represent half of the new-onset seizures in older adults and can progress to acute symptomatic status epilepticus (ASySE) in 52–72% of the patients. Common etiologies for ASyS in older adults include acute stroke and metabolic disturbances. For ASySE, common etiologies are acute stroke and anoxic brain injury (ABI). Initial testing for ASyS should be consistent with the most common and urgent etiologies. A 20-min electroencephalogram (EEG) is less sensitive in older adults than in younger adults and might not help predict chronic epilepsy. The prolonged postictal phase is an additional challenge for acute management. Studies note that 30% of older adults with ASyS subsequently develop epilepsy. The risk of wrongly equating ASyS as the first seizure of epilepsy is higher in older adults due to the increased long-term challenges with chronic anti-seizure medication (ASM) treatment. Specific challenges to managing ASyS in older adults are related to their chronic comorbidities and polypharmacy. It is unclear if the prognosis of ASyS is dependent on the underlying etiology. Short-term mortality is 1.6 to 3.6 times higher than younger adults. ASySE has high short-term mortality, especially when it is secondary to acute stroke. An acute symptomatic etiology of ASySE had five times increased risk of short-term mortality compared to other types of etiology.

Predictive Factors of Acute Symptomatic Seizures in Patients With Ischemic Stroke Due to Large Vessel Occlusion

Introduction

Acute symptomatic seizures (ASz) after ischemic stroke are associated with increased mortality; therefore, identifying predictors of ASz is important. The purpose of this study was to analyze predictors of ASz in a population of patients with ischemic stroke due to large arterial vessel occlusion (LVO).

Materials and Methods

This retrospective study examined patients with acute ischemic stroke caused by LVO between 2016 and 2020. Identification of predictive factors was performed using univariate and subsequent multiple logistic regression analysis. In addition, subgroup analysis regarding seizure semiology and time of seizure occurrence (≤ 24 h and > 24 h after stroke) was performed.

Results

The frequency of ASz among 979 patients was 3.9 % (n = 38). Univariate logistic regression analysis revealed an increased risk of ASz in patients with higher National Institutes of Health Stroke Scale (NIHSS) score at admission or 24 h after admission, hypernatremia at admission ≥ 145 mmol/L, and pneumonia. Further multiple logistic regression analysis revealed that NIHSS 24 h after admission was the strongest predictor of ASz, particularly relating to ASz occurring later than 24 h after stroke. Patients who experienced a seizure within the first 24 h after stroke were more likely to have a generalized tonic-clonic (GTCS) and focal motor seizure; beyond 24 h, seizures with impaired awareness and non-convulsive status epilepticus were more frequent.

Conclusion

NIHSS score 24 h after admission is a strong predictive factor for the occurrence of ASz in patients with ischemic stroke caused by LVO. The semiology of ASz varied over time, with GTCS occurring more frequently in the first 24 h after stroke.

Immune Pathways in Etiology, Acute Phase, and Chronic Sequelae of Ischemic Stroke

Inflammation and immune mechanisms are crucially involved in the pathophysiology of the development, acute damage cascades, and chronic course after ischemic stroke. Atherosclerosis is an inflammatory disease, and, in addition to classical risk factors, maladaptive immune mechanisms lead to an increased risk of stroke. Accordingly, individuals with signs of inflammation or corresponding biomarkers have an increased risk of stroke. Anti-inflammatory drugs, such as IL (interleukin)-1β blockers, methotrexate, or colchicine, represent attractive treatment strategies to prevent vascular events and stroke. Lately, the COVID-19 pandemic shows a clear association between SARS-CoV2 infections and increased risk of cerebrovascular events. Furthermore, mechanisms of both innate and adaptive immune systems influence cerebral damage cascades after ischemic stroke. Neutrophils, monocytes, and microglia, as well as T and B lymphocytes each play complex interdependent roles that synergize to remove dead tissue but also can cause bystander injury to intact brain cells and generate maladaptive chronic inflammation. Chronic systemic inflammation and comorbid infections may unfavorably influence both outcome after stroke and recurrence risk for further stroke. In addition, stroke triggers specific immune depression, which in turn can promote infections. Recent research is now increasingly addressing the question of the extent to which immune mechanisms may influence long-term outcome after stroke and, in particular, cause specific complications such as poststroke dementia or even poststroke depression.

Mechanical thrombectomy does not increase the risk of acute symptomatic seizures in patients with an ischaemic stroke: a propensity score matching study

Background

Mechanical thrombectomy and systemic thrombolysis are important therapies for stroke patients. However, there is disagreement about the accompanying risk of acute symptomatic seizures.

Methods

A retrospective analysis of patients with an acute ischaemic stroke caused by large vessel occlusion was performed. The patients were divided into four groups based on whether they received either mechanical thrombectomy (MT) or systemic thrombolysis (ST; group 1: MT+/ST−; group 2: MT+/ST+; group 3: MT−/ST+; group 4: MT−/ST−). Propensity score matching was conducted for each group combination (1:3, 1:4, 2:3, 2:4, 1:2, 3:4) using the covariates “NIHSS at admission”, “mRS prior to event” and “age”. The primary endpoint was defined as the occurrence of acute symptomatic seizures.

Results

A total of 987 patients met the inclusion criteria, of whom 208, 264, 169 and 346 belonged to groups 1, 2, 3 and 4, respectively. Propensity score matched groups consisted of 160:160, 143:143, 156:156, 144:144, 204:204 and 165:165 patients for the comparisons 1:3, 1:4, 2:3, 2:4, 1:2 and 3:4, respectively. Based on chi-squared tests, there was no significant difference in the frequency of acute symptomatic seizures between the groups. Subgroups varied in their frequency of acute symptomatic seizures, ranging from 2.8 to 3.8%, 2.8–4.4%, 3.6–3.8% and 4.9–6.3% in groups 1, 2, 3 and 4, respectively.

Conclusion

There was no association between MT or ST and an increased risk of acute symptomatic seizures in patients with an acute ischaemic stroke caused by large vessel occlusion who were treated at a primary stroke centre.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00415-022-10968-5.

Asymmetric distribution of enlarged perivascular spaces in centrum semiovale may be associated with epilepsy after acute ischemic stroke

Objective

To investigate the factors influencing enlarged perivascular space (EPVS) characteristics at the onset of acute ischemic stroke (AIS), and whether the PVS characteristics can predict later post‐stroke epilepsy (PSE).

Methods

A total of 312 patients with AIS were identified, of whom 58/312 (18.6%) developed PSE. Twenty healthy participants were included as the control group. The number of PVS in the basal ganglia (BG), centrum semiovale (CS), and midbrain (MB) was manually calculated on T₂‐weighted MRI. The scores and asymmetry index (AI) of EPVS in each region were compared among the enrolled participants. Other potential risk factors for PSE were also analyzed, including NIHSS at admission and stroke etiologies.

Results

The EPVS scores were significantly higher in the bilateral BG and CS of AIS patients compared to those of the control group (both p < 0.01). No statistical differences in EPVS scores in BG, CS, and MB were obtained between the PSE group and the nonepilepsy AIS group (all p > 0.01). However, markedly different AI scores in CS were found between the PSE group and the nonepilepsy AIS group (p = 0.004). Multivariable analysis showed that high asymmetry index of EPVS (AI≥0.2) in CS was an independent predictor for PSE (OR = 3.7, 95% confidence interval 1.5–9.1, p = 0.004).

Conclusions

Asymmetric distribution of EPVS in CS may be an independent risk factor and a novel imaging biomarker for the development of PSE. Further studies to understand the mechanisms of this association and confirmation with larger patient populations are warranted.

Hospital Revisits for Post-Ischemic Stroke Epilepsy after Acute Stroke Interventions

OBJECTIVES

Improvements in acute stroke care have led to an increase in ischemic stroke survivors, who are at risk for development of post-ischemic stroke epilepsy (PISE). The impact of therapies such as thrombectomy and thrombolysis on risk of hospital revisits for PISE is unclear. We utilized administrative data to investigate the association between stroke treatment and PISE-related visits.

MATERIALS AND METHODS

Using claims data from California, New York, and Florida, we performed a retrospective analysis of adult survivors of acute ischemic strokes. Patients with history of epilepsy, trauma, infections, or tumors were excluded. Included patients were followed for a primary outcome of revisits for seizures or epilepsy. Cox proportional hazards regression was used to identify covariates associated with PISE.

RESULTS

In 595,545 included patients (median age 74 [IQR 21], 52% female), the 6-year cumulative rate of PISE-related revisit was 2.20% (95% CI 2.16-2.24). In multivariable models adjusting for demographics, comorbidities, and indicators of stroke severity, IV-tPA (HR 1.42, 95% CI 1.31-1.54, p<0.001) but not MT (HR 1.62, 95% CI 0.90-1.50, p=0.2) was associated with PISE-related revisit. Patients who underwent decompressive craniectomy experienced a 2-fold increase in odds for returning with PISE (HR 2.35, 95% CI 1.69-3.26, p<0.001). In-hospital seizures (HR 4.06, 95% CI 3.76-4.39, p<0.001) also elevated risk for PISE.

SIGNIFICANCE

We demonstrate that ischemic stroke survivors who received IV-tPA, underwent decompressive craniectomy, or experienced acute seizures were at increased risk PISE-related revisit. Close attention should be paid to these patients with increased potential for long-term development of and re-hospitalization for PISE.

Effect of Reperfusion Therapies on Incidence of Early Post-Stroke Seizures

Objective: This study aimed to determine the effect of reperfusion therapies on the occurrence of early post-stroke seizures (PSS) in patients with acute ischemic stroke (AIS). Background: Reperfusion therapies are paramount to the treatment of stroke in the acute phase. However, their effect on the incidence of early seizures after an AIS remains unclear. Design and Methods: The stroke database at Hamad Medical Corporation was used to identify all patients who received reperfusion therapies for AIS from 2016 to 2019. They were matched with patients of similar diagnosis, gender, age, and stroke severity as measured by National Institutes of Health Stroke Scale (NIHSS) who did not receive such treatment. The rates of early PSS were calculated for each group. Results: The results showed that 508 patients received reperfusion therapies (342 had IV thrombolysis only, 70 had thrombectomies only, and 96 had received both), compared with 501 matched patients receiving standard stroke unit care. Patients who received reperfusion therapies were similar to their matched controls for mean admission NIHSS score (9.87 vs. 9.79; p = 0.831), mean age (53.3 vs. 53.2 years; p = 0.849), and gender distribution (85 vs. 86% men; p = 0.655). The group receiving reperfusion therapies was found to have increased stroke cortical involvement (62 vs. 49.3%, p < 0.001) and hemorrhagic transformation rates (33.5 vs. 18.6%, p < 0.001) compared with the control group. The rate of early PSS was significantly lower in patients who received reperfusion therapies compared with those who did not (3.1 vs. 5.8%, respectively; p = 0.042). When we excluded seizures occurring at stroke onset prior to any potential treatment implementation, the difference in early PSS rates between the two groups was no longer significant (2.6 vs. 3.9%, respectively; p = 0.251). There was no significant difference in early PSS rate based on the type of reperfusion therapy either (3.2% with thrombolysis, 2.9% with thrombectomy, and 3.1% for the combined treatment, p = 0.309). Conclusions: Treatment of AIS with either thrombectomy, thrombolysis, or both does not increase the risk of early PSS.

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.

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 of Post-stroke Epilepsy Following Stroke-Associated Acute Symptomatic Seizures

Objective: Post-stroke epilepsy (PSE) is associated with increased morbidity and mortality. Stroke-associated acute symptomatic seizures are an important risk factor: 20.8–34.3% of these patients will go on to develop PSE. Identifying these “high risk” individuals may result in earlier PSE diagnosis, treatment, and avoidance of seizure-related morbidity. This study was to identify predictors of PSE development in patients with stroke-associated acute symptomatic seizures.

Participants and Methods: This was a retrospective cohort study of 167 patients with stroke-associated acute symptomatic seizures admitted to the Neurology Department of a tertiary Hospital of China, from 1 May 2006 to 30 January 2020. Both those with primary ischemic stroke and intracerebral hemorrhage were included in the study. Patient demographics, medical history, stroke-associated, and seizure-related variables were evaluated with univariable analysis and multivariable Cox regression analysis. PSE was defined as unprovoked seizures occurring > 7 days post-stroke. Data points were extracted from medical records and supplemented by tele-interview.

Results: Of the 167 patients with stroke-associated acute symptomatic seizures, 49 (29.3%) developed PSE. NIHSS score > 14 [hazard ratio (HR) 2.98, 95% CI 1.57–5.67], longer interval from stroke to acute symptomatic seizures (days 4–7 post-stroke) (HR 2.51, 95% CI 1.37–4.59) and multiple acute symptomatic seizures (HR 5.08, 95% CI 2.58–9.99) were independently associated with PSE development. This association remained in the sub-analysis within the ischemic stroke cohort. In the sub-analysis of the hemorrhagic stroke cohort, multilobar involvement (HR 4.80, 95% CI 1.49–15.39) was also independently associated with development of PSE. Further, we developed a nomogram to predict individual risk of developing PSE following stroke-associated acute symptomatic seizures. The nomogram showed a C-index of 0.73.

Conclusion: More severe neurofunctional deficits (NIHSS score > 14), longer interval from stroke to acute symptomatic seizures (days 4–7 post-stroke), and multiple acute symptomatic seizures were independently associated with development of PSE in patients with stroke-associated acute symptomatic seizures. This knowledge may increase clinical vigilance for development of PSE, facilitating rapid diagnosis and treatment initiation, and subsequently reduce seizure-related morbidity.

Seizures after Ischemic Stroke: A Matched Multicenter Study

Objective

The purpose of this study was to identify risk factors for acute symptomatic seizures and post‐stroke epilepsy after acute ischemic stroke and evaluate the effects of reperfusion treatment.

Methods

We assessed the risk factors for post‐stroke seizures using logistic or Cox regression in a multicenter study, including adults from 8 European referral centers with neuroimaging‐confirmed ischemic stroke. We compared the risk of post‐stroke seizures between participants with or without reperfusion treatment following propensity score matching to reduce confounding due to treatment selection.

Results

In the overall cohort of 4,229 participants (mean age 71 years, 57% men), a higher risk of acute symptomatic seizures was observed in those with more severe strokes, infarcts located in the posterior cerebral artery territory, and strokes caused by large‐artery atherosclerosis. Strokes caused by small‐vessel occlusion carried a small risk of acute symptomatic seizures. 6% developed post‐stroke epilepsy. Risk factors for post‐stroke epilepsy were acute symptomatic seizures, more severe strokes, infarcts involving the cerebral cortex, and strokes caused by large‐artery atherosclerosis. Electroencephalography findings within 7 days of stroke onset were not independently associated with the risk of post‐stroke epilepsy. There was no association between reperfusion treatments in general or only intravenous thrombolysis or mechanical thrombectomy with the time to post‐stroke epilepsy or the risk of acute symptomatic seizures.

Interpretation

Post‐stroke seizures are related to stroke severity, etiology, and location, whereas an early electroencephalogram was not predictive of epilepsy. We did not find an association of reperfusion treatment with risks of acute symptomatic seizures or post‐stroke epilepsy. ANN NEUROL 2021;90:808–820

Current advances on mechanisms and treatment of post-stroke seizures

Cerebrovascular diseases are among the most common causes of seizures in adults, especially in the elderly. With the increased incidence of stroke, the population with post-stroke seizures has grown, leading to the increased awareness of this disorder in the society. The most common seizure type after stroke is the focal seizure with or without evolution into bilateral convulsive seizures. Post-stroke seizures impair the quality of life, as well as the physical and mental health of those patients. Currently, the pathological and physical processes of post-stroke seizures are not quite clear yet. In this review, we summarize current advances in the pathogenesis, risk factors, and therapeutic targets of post-stroke seizures.

Acute symptomatic seizures and epilepsy after mechanical thrombectomy. A prospective long-term follow-up study

INTRODUCTION

New treatments for acute ischaemic stroke, such as mechanical thrombectomy, can achieve reperfusion of large ischaemic tissue. Some studies have suggested that reperfusion therapies can increase the risk of suffering acute symptomatic seizure (ASS) and poststroke epilepsy (PSE). The aim of the study was to determine the incidence of ASS and PSE in patients undergoing thrombectomy, and related factors.

PATIENTS AND METHODS

This was a retrospective single-centre study including patients with ischaemic stroke and NIHSS> 8 treated with thrombectomy with a follow-up ≥5 years. We evaluated several epidemiological, radiological, clinical and electroencephalographic variables.

RESULTS

Of the 344 included patients, 21 (6.1%) presented ASS, 53 (15.40%) died in the acute phase, and 13 (4.46%) died during the first year. The degree of reperfusion (p 0.029), advanced age (p 0.035), and haemorrhagic transformation (p 0.038) increased the risk of suffering ASS, with degree of reperfusion being an independent factor, OR 2.02 (1.21-4.64). The incidence of PSE was 4.12% in the first year, 3.72% in the second, and 1.61% in the fifth. The accumulated incidence at 5 years was 8.93%. Related risk factor for suffering PSE was ASS (p < 0.001), yielding an OR value of 2.00 (1.28-3.145).

CONCLUSIONS

Thrombectomy doesn´t increase the risk of ASS. A higher percentage of reperfusion, advanced age, and haemorrhagic transformation are associated with an increased risk of ASS. ASS is a risk factor for suffering PSE. In terms of mortality, having suffered ASS and/or PSE does not increase acute or long-term mortality.

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.

Multifactorial Predictors of Late Epileptic Seizures Related to Stroke: Evaluation of the Current Possibilities of Stratification Based on Existing Prognostic Models-A Comprehensive Review

Background: Epilepsy associated with strokes is a significant clinical and public health problem and has a negative impact on prognosis and clinical outcome. A late epileptic seizure occurring seven days after stroke is actually equated with poststroke epilepsy due to the high risk of recurrence. Predictive models evaluated in the acute phase of stroke would allow for the stratification and early selection of patients at higher risk of developing late seizures. Methods: The most relevant papers in this field were reviewed to establish multifactorial predictors of late seizures and attempt to standardize and unify them into a common prognostic model. Results: Clinical and radiological factors have become the most valuable and reproducible predictors in many reports, while data on electroencephalographic, genetic, and blood biomarkers were limited. The existing prognostic models, CAVE and SeLECT, based on relevant, readily available, and routinely assessed predictors, should be validated and improved in multicenter studies for widespread use in stroke units. Conclusions: Due to contradictory reports, a common and reliable model covering all factors is currently not available. Further research might refine forecasting models by incorporating advanced radiological neuroimaging or quantitative electroencephalographic analysis.

Intravenous thrombolysis or mechanical thrombectomy do not increase risk of acute symptomatic seizures in patients with ischemic stroke

Recent data have suggested that performing recanalizing therapies in ischemic stroke might lead to an increased risk of acute symptomatic seizures. This applies to both intravenous thrombolysis and mechanical thrombectomy. We therefore determined the frequency of acute symptomatic seizures attributable to these two recanalization therapies using a large, population-based stroke registry in Central Europe. We performed two matched 1:1 case–control analyses. In both analyses, patients were matched for age, stroke severity on admission and pre-stroke functional status. The first analysis compared patients treated with intravenous thrombolysis to a non-recanalization control group. To isolate the effect of mechanical thrombectomy, we compared patients with both mechanical thrombectomy and intravenous thrombolysis to those with only intravenous thrombolysis treatment in a second analysis. From 135,117 patients in the database, 13,356 patients treated with only intravenous thrombolysis, and 1013 patients treated with both intravenous thrombolysis and mechanical thrombectomy were each matched to an equivalent number of controls. Patients with intravenous thrombolysis did not suffer from clinically apparent acute symptomatic seizures significantly more often than non-recanalized patients (treatment = 199; 1.5% vs. control = 237; 1.8%, p = 0.07). Mechanical thrombectomy in addition to intravenous thrombolysis also was not associated with an increased risk of acute symptomatic seizures, as the same number of patients suffered from seizures in the treatment and control group (both n = 17; 1.7%, p = 1). In a large population-based stroke registry, the frequency of clinically apparent acute symptomatic seizures was not increased in patients who received either intravenous thrombolysis alone or in conjunction with mechanical thrombectomy.

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.

Incidence and Association of Reperfusion Therapies With Poststroke Seizures: A Systematic Review and Meta-Analysis

BACKGROUND AND PURPOSE

We performed a systematic review and meta-analysis to assess the incidence and risk of seizures following acute stroke reperfusion therapy (intravenous thrombolysis [IVT] with r-tPA [recombinant tissue-type plasminogen activator], mechanical thrombectomy or both).

METHODS

We searched major databases (MEDLINE, SCOPUS, and Cochrane Library) for articles published between 1995 and October 28, 2019. The primary outcome was the overall and treatment specific pooled incidence of poststroke seizures (PSS) following acute reperfusion therapy. We also computed the pooled incidence of early poststroke seizures and late poststroke seizures separately for all studies. We derived the risk of PSS associated with IVT in the pooled cohort of patients who received only IVT. The small number of studies (<3) that reported on the risk of PSS associated with mechanical thrombectomy alone or in combination with IVT did not allow us to compute an estimate of the risk of seizures associated with this therapy.

RESULTS

We identified 13 753 patients with stroke, of which 592 had seizures. The pooled incidence of PSS was 5.9 % (95% CI, 4.2%-8.2%). PSS incidence rates among patients with stroke treated with IVT, mechanical thrombectomy, and both were respectively 6.1% (95% CI, 3.6%-10.2%), 5.9% (95% CI, 4.1%-8.4%), and 5.8 % (95% CI, 3.0%-10.9%). The incidence of late PSS was 6.7% (95% CI, 4.01%-11.02%) and that of early PSS was 3.14% (95% CI, 2.05%-4.76%). The pooled odds ratio for the association between IVT and PSS was 1.24 (95% CI, 0.75-2.05).

CONCLUSIONS

The findings of this meta-analysis suggest that about one in 15 ischemic stroke patients treated with IVT, mechanical thrombectomy, or both develop seizures independently of the specific reperfusion treatment that they received.

Early poststroke seizures following thrombolysis and/or thrombectomy for acute stroke: Clinical and stroke characteristics

In this retrospective study, we explored the clinical and stroke characteristics of patients treated with thrombolysis and/or mechanical thrombectomy for an acute stroke and experiencing early poststroke seizures within 7 days of the cerebrovascular accident. Patients with prior epilepsy, primary intracerebral hemorrhage or transient ischemic attacks, or taking antiepileptic drugs were excluded. We retrospectively identified 32 patients admitted between 2010 and 2016 (mean age 75 years; range: 49-90; 14 females and 18 males). A cortical stroke was found in more than 70% of patients. Most epileptic seizures were focal aware (46.7%) or generalized convulsive (43.3%). The median time between stroke onset and seizure occurrence was 2 days; in 75.9% of the cases, seizures occurred within the first 3 days. This retrospective case series is the largest published so far providing details on clinical features of patients with early poststroke seizures following different reperfusion therapies, not only restricted to intravenous (i.v.) thrombolysis. Early poststroke seizures following reperfusion therapies are associated with cortical stroke involvement, are usually focal without impairment of awareness or generalized convulsive, and occur mostly within the first 3 days. Further studies are needed to clarify whether the low prevalence of focal impaired awareness seizures (and nonconvulsive seizures/status) is real or reflects the failure to recognize and correctly diagnose this seizure type in the acute poststroke period (risk of underascertainment due to the lack of systematic video-electroencephalogram (EEG) recording in patients with stroke and difficulties in recognizing these seizures). This article is part of the Special Issue "Seizures & Stroke".

Acute symptomatic seizures and epilepsy after mechanical thrombectomy

PURPOSE

The purpose of this study was to assess the incidence of acute symptomatic seizures and poststroke epilepsy (PSE) in a well-characterized cohort of patients treated with mechanical thrombectomy. In addition, we aimed to describe the dynamics of blood markers of brain injury in patients that developed PSE.

METHODS

Participants of the prospective AnStroke Trial of anesthesia method during mechanical thrombectomy were included and acute symptomatic seizures and PSE ascertained by medical records review. Blood markers neurofilament light (NFL), tau, glial fibrillary acidic protein (GFAP), S100 calcium-binding protein B (S100B), and neuron-specific enolase (NSE) were assessed.

RESULTS

A total of 90 patients with acute anterior ischemic stroke were included. Median National Institutes of Health Stroke Scale (NIHSS) at admission to hospital was 18 (IQR 15-22). Recanalization was achieved in 90%. No patients had epilepsy prior to the ischemic stroke. Four patients (4.4%) had acute symptomatic seizures and four patients (4.4%) developed PSE during the follow-up time (to death or last medical records review) of 0-4.5 years (median follow-up 1070 days IQR 777-1306), resulting in a two-year estimated PSE risk of 5.3% (95%CI: 0.2-10.4%). Blood markers of brain injury (NFL, tau, GFAP, S100B, and NSE) were generally above the cohort median in patients that developed PSE.

CONCLUSIONS

The incidence of PSE after mechanical thrombectomy was low in our cohort. All blood biomarkers displayed interesting sensitivity and specificity. However, the number of PSE cases was small and more studies are needed on risk factors for PSE after mechanical thrombectomy. The potential of blood markers of brain injury markers to contribute to assessment of PSE risk should be explored further. This article is part of the Special Issue "Seizures & Stroke".

Reperfusion therapies and poststroke seizures

Seizures are not only a frequent complication of stroke but have been associated with an unfavorable functional and vital outcome of patients who have had stroke. Facing a new paradigm of acute standard stroke care, acute symptomatic seizures in this clinical setting deserve to be rethought. Reperfusion therapies, the gold standard treatment for acute ischemic stroke, improve long-term survival and outcome of patients who have had stroke and have been associated both with clinical seizures and the occurrence of epileptiform activity in the electroencephalogram (EEG). This narrative review describes the different physiopathological mechanisms underlying the possible association between reperfusion therapies and seizures, both acute symptomatic seizures and unprovoked seizures, and the current evidence regarding the risk of poststroke seizures in treated patients. It also identifies the gaps in our knowledge to foster future studies in this field. By different mechanisms, reperfusions therapies may have opposing effects on the risk of poststroke seizures. There is a need for a better definition of the specific physiopathology of seizures in clinical practice, as many factors can be recognized. Additionally, most of the current clinical evidence refers to acute symptomatic seizures and not to unprovoked seizures or poststroke epilepsy, and our analysis does not support the existence of a strong association between thrombolysis and poststroke seizures. So far, the impact of reperfusion therapies on the frequency of poststroke seizures is unclear. To study this effect, many clinical challenges must be overcome, including a better and clear operational definition of seizures and stroke characteristics, the standard of stroke and epilepsy care and EEG monitoring, and the degree of reperfusion success. Prospective, high quality, larger, and longer follow-up multicentric studies are urgently needed. Additionally, stroke registries can also prove useful in better elucidate whether there is an association between reperfusion therapies and seizures. This article is part of the Special Issue "Seizures & Stroke".

Intravenous thrombolysis with tPA and cortical involvement increase the risk of early poststroke seizures: Results of a case-control study

The aim of this study was to identify the risk factors for early poststroke seizures (PSS) in patients with acute ischemic stroke. We undertook a case-control study at a single stroke center. Patients with seizure occurring during the first 7 days following ischemic stroke admitted between 2010 and 2016 were retrospectively identified and matched with controls (patients with stroke without early PSS) for age and sex. We included 79 cases and 158 controls. Blood sugar levels on admission, stroke localization, National Institutes of Health Stroke Scale (NIHSS) and Rankin score, and intravenous (i.v.) thrombolysis with recombinant tissue plasminogen activator (rtPA) were statistically associated with early PSS in univariate analysis. Multiple logistic regression after forward and backward variable selection identified cortical stroke localization (odds ratio (OR): 2.49; 95% confidence intervals (CI): 1.35 to 4.59; p = 0.003) and i.v. thrombolysis (OR: 2.26; 95% CI: 1.16 to 4.43; p = 0.008) as variables independently associated with early PSS. Cortical involvement and i.v. thrombolysis are independent risk factors associated with the occurrence of early PSS. This association is not explained by age or sex, concomitant drugs, diabetes or alcoholism, sodium and cholesterol levels, blood pressure on admission, stroke etiology or severity, and hemorrhage following i.v. thrombolysis. Further studies are required to fully elucidate the association between different reperfusion therapies and early PSS. This article is part of the Special Issue "Seizures & Stroke".

Risk Factors for Epilepsy After Thrombolysis for Ischemic Stroke: A Cohort Study

The effects of thrombolysis in seizure and epilepsy after acute ischemic stroke have been poorly explored. In this study, we examine risk factors and consequences of intravenous rt-PA for treatment of acute ischemic stroke. In a retrospective cohort study we evaluate risk factors for seizure and epilepsy after stroke thrombolysis, as well as the impact of seizures and epilepsy in outcome of stroke patients. In our cohort, mean age of patients was 67.2 years old (SD = 13.1) and 79 of them (51.6%) were male and. Initial NIHSS mean score were 10.95 (SD = 6.25). Three months NIHSS mean score was 2.09 (SD = 3.55). Eighty seven (56.9%) patients were mRS of 0–1 after thrombolysis. Hemorrhagic transformation was observed in 22 (14.4%) patients. Twenty-one (13.7%) patients had seizures and 15 (9.8%) patients developed epilepsy after thrombolysis. Seizures were independently associated with hemorrhagic transformation (OR = 3.26; 95% CI = 1.08–9.78; p = 0.035) and with mRS ≥ 2 at 3 months after stroke (OR = 3.51; 95% CI = 1.20–10.32; p = 0.022). Hemorrhagic transformation (OR = 3.55; 95% CI = 1.11–11.34; p = 0.033) and mRS ≥ 2 at 3 months (OR = 5.82; 95% CI = 1.45–23.42; p = 0.013) were variables independently associated with post-stroke epilepsy. In our study, independent risks factors for poor outcome in stroke thrombolysis were age (OR = 1.03; 95% CI = 1.01–1.06; p = 0.011), higher NIHSS (OR = 1.08; 95% CI = 1.03–1.14; p = 0.001), hemorrhagic transformation (OR = 2.33; 95% CI = 1.11–4.76; p = 0.024), seizures (OR = 3.07; 95% CI = 1.22–7.75; p = 0.018) and large cortical area (ASPECTS ≤ 7) (OR = 2.04; 95% CI = 1.04–3.84; p = 0.036). Concluding, in this retrospective cohort study, the neurological impairment after thrombolysis (but not before) and hemorrhagic transformation remained independent risk factors for seizures or post-stroke epilepsy after thrombolysis. Moreover, we observed that seizures emerged as an independent risk factor for poor outcome after thrombolysis therapy in stroke patients (OR = 3.07; 95% CI = 1.22–7.75; p = 0.018).

Monitoring for Poststroke Seizures

It is unpredictable which stroke survivors will experience a seizure following a stroke. Stroke is a major cause of seizures. Critical care nurses need to know the risk factors, type of stroke at risk, stroke location, and severity for the poststroke patient who is at risk for an early or late seizure. Poststroke seizures require appropriate nursing assessments, management, and support.

Role of cerebral glutamate in post-stroke epileptogenesis

Stroke is one of the most important causes of acquired epilepsy in the adult population. While factors such as cortical involvement and haemorrhage have been associated with increased seizure risk, the mechanisms underlying the development of epilepsy after stroke remain unclear. One hypothesised mechanism is an excitotoxic effect of abnormal glutamate release following a stroke. Cerebral extracellular glutamate levels are known to rise in the setting of acute stroke, and numerous studies have implicated glutamate in the pathogenesis of seizures and epilepsy, both through direct measurement of glutamate from the epileptic brain and by analysis of receptors and transporters central to glutamate homeostasis. While experimental evidence suggests the cellular injury induced by glutamate exposure may lead to development of an epileptic phenotype, there is little direct data linking the rise in glutamate during stroke with the later development of epilepsy. Clinical research in this field has been hampered by the lack of non-invasive methods to measure cerebral glutamate. However, with the increasing availability of 7T MRI technology, Magnetic Resonance Spectroscopy is able to better resolve glutamate from other chemical species at this field strength, and Glutamate Chemical Exchange Saturation Transfer (GluCEST) imaging has been applied to localise epileptic foci in non-lesional focal epilepsy. This review outlines the evidence implicating a pivotal role for cerebral glutamate in the development of post-stroke epilepsy, and exploring the role of MRI in studying glutamate as a biomarker and therefore its suitability as a molecular target for anti-epileptogenic therapies. We hypothesise that the rise in glutamate levels in the setting of acute stroke is a clinically relevant biomarker for the development of post-stroke epilepsy.

The risk of new-onset epilepsy and refractory epilepsy in older adult stroke survivors

Objective

Our study objectives were to identify factors associated with new-onset epilepsy and refractory epilepsy among older adult stroke survivors and to evaluate the receipt of diagnostic care and mortality for participants who developed epilepsy.

Methods

We conducted a population-based, retrospective cohort study using linked, administrative health care databases. The Ontario Stroke Registry was used to identify patients 67 years and older who were hospitalized for a stroke at a designated stroke center in Ontario, Canada, between April 1, 2003, and March 31, 2009, and were previously free of epilepsy. Multivariable Fine–Gray hazard models were used to examine risk factors of epilepsy and refractory epilepsy, accounting for the competing risk of death.

Results

Among 19,138 older adults hospitalized for a stroke, 210 (1.1%) developed epilepsy and 27 (12.9%) became refractory to antiepileptic drugs. Within 1 year of epilepsy diagnosis, 24 (11.4%) patients were assessed with EEG and 19 (9.0%) with MRI. In multivariable analysis, younger age and thrombolysis receipt significantly increased epilepsy risk. Lesser stroke severity and anticoagulant medication receipt also significantly increased epilepsy risk; however, these effects decreased over time. Younger age and female sex were the only risk factors of refractory epilepsy. In the 5 years following epilepsy diagnosis, 97 (46.2%) participants died of any cause.

Conclusions

Older adult stroke survivors are less likely to develop epilepsy and pharmacologically refractory epilepsy. An estimated 86.6% of deaths among older adult stroke survivors with new-onset epilepsy are attributed to causes other than stroke or epilepsy.

Incidence, Implications, and Management of Seizures Following Ischemic and Hemorrhagic Stroke

PURPOSE OF REVIEW

In this review, we summarize the recent literature regarding the incidence and treatment of seizures arising after ischemic and hemorrhagic strokes. Additionally, we identify open questions in guidelines and standard clinical care to aid future studies aiming to improve management of seizures in post-stroke patients.

RECENT FINDINGS

Studies demonstrate an increasing prevalence of seizures following strokes, probably a consequence of advances in post-stroke management and expanding use of continuous EEG monitoring. Post-stroke seizures are associated with longer hospitalization and increased mortality; therefore, prevention and timely treatment of seizures are important. The standard of care is to treat recurrent seizures with anti-epileptic drugs (AEDs) regardless of the etiology. However, there are no established guidelines currently for prophylactic use of AEDs following a stroke. The prevalence of post-stroke seizures is increasing. Further studies are needed to determine the risk factors for recurrent seizures and epilepsy after strokes and optimal treatment strategies.

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.

Stroke-related epilepsy

Stroke is the cause of about 10% of all epilepsy and 55% of newly diagnosed seizures among the elderly. Although recent advances in acute stroke therapy have improved longevity, there has been a consequent rise in the prevalence of stroke-related epilepsy (STRE). Many clinical studies make a distinction between early (within 7 days of onset of stroke) and late (beyond 7 days of onset of stroke) seizures based on presumed pathophysiological differences. Although early seizures are thought to be the consequence of local metabolic disturbances without altered neuronal networks, late seizures are thought to occur when the brain has acquired a predisposition for seizures. Overall, STRE has a good prognosis, being well controlled by antiepileptic drugs. However, up to 25% of cases become drug resistant. STRE can also result in increased morbidity, longer hospitalization, greater disability at discharge and greater resource utilization. Additional controlled trials are needed to explore the primary and secondary prevention of STRE as well as to provide high-quality evidence on efficacy and tolerability of antiepileptic drugs to guide treatment of STRE. Robust pre-clinical and clinical prediction models of STRE are also needed to develop treatments to prevent the transformation of infarcted tissue into an epileptic focus.