Non-convulsive status epilepticus after ischemic stroke: a hospital-based stroke cohort study

Status Epilepticus after mechanical thrombectomy: The role of early EEG assessment in Stroke Unit, clinical and radiological prognostication

BACKGROUND

Convulsive (CSE) and non-convulsive (NCSE) Status Epilepticus are a complication in 0.2-0.3% ischemic strokes. Large stroke and cortical involvement are the main risk factors for developing SE. This study evaluates the prevalence of SE in patients treated with endovascular thrombectomy (EVT) through EEG recording within 72- h from admission. Moreover, we compared clinical, radiological, and outcome measures in SE and no-SE patients.

MATERIALS AND METHODS

We collected retrospectively demographical and clinical characteristics of acute ischemic stroke patients who underwent EVT, admitted in the Stroke Unit (SU) of the University Hospital of Trieste between January 2018 and March 2020 who underwent EEG recording within 72- h from the symptoms' onset.

RESULTS

Out of 247 EVT patients, 138 met the inclusion criteria, of whom 9 (6.5%) showed SE with median onset time of 1 day (IQR 1-2). No difference was found between the two groups as for age, sex, risk factors, grade of recanalization, etiology of stroke, and closed vessel. The no-SE group presented higher NIHSS improvement rate (p=0.025) compared to the SE group. The sum of the lobes involved in the ischemic lesion was significantly higher in SE group (p=0.048).

CONCLUSION

SE after EVT in large strokes is a non-rare complication, with most being NCSE. Performing a rapid EEG assessment in a Stroke Unit setting may allow for a prompt recognition and treatment of SE in the acute/hyper-acute phase. SE may be correlated with worse clinical outcomes in patients with large vessel occlusion.

Ictal EEG: Etiology and Mortality in Older Adults With Nonconvulsive Status Epilepticus

Clinical-electroencephalogram (EEG), as well as etiological and prognostic data on subtypes of nonconvulsive status epilepticus (NCSE) are yet to be established. Objective: Evaluate the clinical semiology and EEG findings and prognostic data of older adults with NCSE. Methodology: Characterize the clinical-EEG and prognostic data in the subtypes of NCSE in older adults consecutively admitted to the emergency room of the Pontifícia Universidade Católica de Campinas (PUC-Campinas) University Hospital. Results: When evaluating 105 older adults with altered consciousness, it was possible to diagnose NCSE in 50 (47.6%) older adults, with a mean age of 72.8 ± 8.8 years. NCSE-coma occurred in 6 cases, with NCSE-without coma in 44 cases. The etiology was structural in 41(82%) cases, metabolic in 5 cases, and unknown etiology in 4 cases. Twelve cases had a history of epileptic seizures. On the EEG, epileptiform discharges (EDs > 2.5 Hz) were present in 34(68%) cases and rhythmic delta activity /lateralized periodic patterns occurred in 35(70%) cases. There was clinical improvement after the initial pharmacological treatment in 36 cases and, within 30 days, 18 cases died. The better prognosis was associated with a good response to initial pharmacological treatment (n = 14) and with EDs > 2.5 Hz on EEG (Fisher's exact test; 26 vs 8; P = .012). Conclusion: Focal NCSE with impaired consciousness was the most frequent subtype. The most frequent finding on the EEG was the recording of focal/regional seizures. A high number of cases showed initial clinical improvement, but mortality was high. The favorable prognosis was associated with initial clinical improvement and the presence of EDs > 2.5 Hz. There was no relationship between EEG patterns and the etiology and subtypes of NCSE in older adults.

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

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

Prognostic value of early electrographic biomarkers of epileptogenesis in high-risk ischaemic stroke patients

BACKGROUND AND PURPOSE

Post-stroke epilepsy (PSE) is frequent. Better prediction of PSE would enable individualized management and improve trial design for epilepsy prevention. The aim was to assess the complementary value of continuous electroencephalography (EEG) data during the acute phase compared with clinical risk factors currently used to predict PSE.

METHODS

A prospective cohort of 81 patients with ischaemic stroke who received early continuous EEG monitoring was studied to assess the association of early EEG seizures, other highly epileptogenic rhythmic and periodic patterns, and regional attenuation without delta (RAWOD, an EEG pattern of stroke severity) with PSE. Clinical risk factors were investigated using the SeLECT (stroke severity; large-artery atherosclerosis; early clinical seizures; cortical involvement; territory of middle cerebral artery) scores.

RESULTS

Twelve (15%) patients developed PSE. The presence of any of the investigated patterns was associated with a risk of epilepsy of 46%, with a sensitivity and specificity of 83% and 78%. The association remained significant after adjusting for the SeLECT score (odds ratio 18.8, interquartile range 3.8-72.7).

CONCLUSIONS

It was found that highly epileptogenic rhythmic and periodic patterns and RAWOD were associated with the development of PSE and complemented clinical risk factors. These findings indicate that continuous EEG provides useful information to determine patients at higher risk of developing PSE and could help individualize care.

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.

Post-Stroke Status Epilepticus: Time of Occurrence May Be the Difference?

(1) Background: Stroke is one of the most frequent causes of status epilepticus (SE) in adults. Patients with stroke and SE have poorer prognosis than those with stroke alone. We described characteristics and prognosis of early- and late-onset post-stroke SE (PSSE). (2) Methods: We retrospectively analyzed consecutive stroke patients who experienced a first SE between August 2012 and April 2021, comparing clinical characteristics, stroke, and SE features between early- versus late-onset SE in relation to patients' outcome. (3) Results: Forty stroke patients experienced PSSE. Fourteen developed an early-onset SE (35%) and twenty-six a late-onset SE (65%). Early-onset SE patients had a slightly higher NIHSS score at admission (6.9 vs. 6.0; p = 0.05). Early-onset SE was more severe than late-onset, according to STESS (Status Epilepticus Severity Score) (3.5 vs. 2.8; p = 0.05) and EMSE (Epidemiology-based Mortality score in Status Epilepticus) score (97.0 vs. 69.5; p = 0.04); furthermore, it had a significant impact on disability at 3-month and 1-year follow-up (p = 0.03 and p = 0.02). SE recurrence and seizures relapse were observed mainly in cases of late-onset SE. (4) Conclusions: Early-onset SE seems to be associated with higher disability in short- and long-term follow-up as possible expression of severe acute brain damage.

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.

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.

Social Relevance and Post-stroke Epilepsy Prevention

Abstract:  Stroke is an important cerebrovascular disease resulting in long-term disability and death. A rare consequence of stroke is structural epilepsy. Here we discuss the importance of post-stroke epilepsy prevention. We look into the occurrence of stroke and epilepsy in the general population, the risk factors and severity of those conditions and the significance of early seizure prevention after the stroke. We analyze published research papers and reviews dealing with this problem. In brief, there is a diagnostic problem leading to ineffective treatment. On one hand preventing seizures in patients with no history of epilepsy, treating them with medications with known side effects. On the other hand by not treating them, risk seizures and future repercussions for their health and wellbeing. Here we propose ways to select patients for treatment and refine the diagnostic considerations for early start of anti-seizure therapy.

Associated Factors and Prognostic Implications of Non-convulsive Status Epilepticus in Ischemic Stroke Patients With Impaired Consciousness

Background and Purpose: Non-convulsive status epilepticus (NCSE) is common in patients with disorders of consciousness and can cause secondary brain injury. Our study aimed to explore the determinants and prognostic significance of NCSE in stroke patients with impaired consciousness.

Method: Consecutive ischemic stroke patients with impaired consciousness who were admitted to a neuro intensive care unit were enrolled for this study. Univariate and multivariable logistic regression were used to identify factors associated with NCSE and their correlation with prognosis.

Results: Among the 80 patients studied, 20 (25%) died during hospitalization, and 51 (63.75%) had unfavorable outcomes at the 3-month follow-up. A total of 31 patients (38.75%) developed NCSE during 24-h electroencephalogram (EEG) monitoring. Logistic regression revealed that NCSE was significantly associated with an increased risk of death during hospital stay and adverse outcomes at the 3-month follow-up. Patients with stroke involving the cerebral cortex or those who had a severely depressed level of consciousness were more prone to epileptogenesis after stroke.

Conclusion: Our results suggest that NCSE is a common complication of ischemic stroke, and is associated with both in-hospital mortality and dependency at the 3-month follow-up. Long-term video EEG monitoring of stroke patients is, therefore required, especially for those with severe consciousness disorders (stupor or coma) or cortical injury.

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.

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.

Early and late-onset nonconvulsive status epilepticus after stroke

BACKGROUND

Nonconvulsive status epilepticus (NCSE) is a condition that needs timely diagnosis and treatment. It has insignificant clinical features and presents high risk of misdiagnosis.

OBJECTIVE

To investigate NCSE among patients with stroke, given that stroke plays an important role in the etiology of NCSE.

METHODS

In this retrospective study, acute stroke patients who were admitted and followed up at a stroke outpatient clinic between January 2013 and March 2016 were included. Patients with previous histories of epilepsy, brain tumor, head trauma, hypertensive encephalopathy, arteriovenous malformation, subarachnoid hemorrhage or cerebral venous thrombosis were excluded. Demographic properties, stroke etiology, imaging method, EEG findings, stroke severity according to the NIHSS score, functional disability and modified Rankin Scale were recorded for all patients.

RESULTS

Thirty-nine out of 792 stoke patients experienced NCSE. The mean age of the study population was 70±1.2 years (min-max: 46‒90). The study population was composed of 28 females (71.8%) and 11 males (28.2%). NCSE had early onset in 23 patients (59%) and late onset in 16 (41%). The early-onset NCSE patients were older and this was statistically significant between the groups (early onset: 73.5±11.5; late onset: 65.9±12.1; p=0.04). A history of previous stroke was more frequent in the late-onset NCSE group (14; 87,5%) than in the early-onset group (11; 47.8%) (p=0.01). The prognosis was worse in the early-onset group, but without statistical significance.

CONCLUSION

Changes in mental status in the early stages of stroke are mostly attributed to stroke itself, but NCSE should be suspected in the right clinical setting, such as in older patients with suspicious anatomical and clinical associations.

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.

Incidence, predictors, and outcomes of post-thrombectomy seizures in the extended time window

Mechanical thrombectomy 6-24 h after the last time where a patient was known to be without signs or symptoms of a stroke is the standard of care for patients with a stroke due to large vessel occlusion. This is referred to as thrombectomy within an extended time window. There have been very few studies looking at patients who had seizures within the first week (early post-stroke seizures) following mechanical thrombectomy in this extended time window. Our study suggests that this group of patients does not have a higher incidence of early post stroke seizures. Our findings do reveal however, that patients who do have early post-stroke seizures may have a less favorable functional outcome at 90 days than those who did not develop early seizures. Hence, rapid identification and subsequent treatment of seizures in these patients is important.

[Electroencephalography in acute stroke]

OBJECTIVE

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

MATERIAL AND METHOD

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

RESULTS

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

CONCLUSION

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

Burden of Epileptiform Activity Predicts Discharge Neurologic Outcomes in Severe Acute Ischemic Stroke

BACKGROUND/OBJECTIVES

Clinical seizures following acute ischemic stroke (AIS) appear to contribute to worse neurologic outcomes. However, the effect of electrographic epileptiform abnormalities (EAs) more broadly is less clear. Here, we evaluate the impact of EAs, including electrographic seizures and periodic and rhythmic patterns, on outcomes in patients with AIS.

METHODS

This is a retrospective study of all patients with AIS aged ≥ 18 years who underwent at least 18 h of continuous electroencephalogram (EEG) monitoring at a single center between 2012 and 2017. EAs were classified according to American Clinical Neurophysiology Society (ACNS) nomenclature and included seizures and periodic and rhythmic patterns. EA burden for each 24-h epoch was defined using the following cutoffs: EA presence, maximum daily burden < 10% versus > 10%, maximum daily burden < 50% versus > 50%, and maximum daily burden using categories from ACNS nomenclature ("rare" < 1%; "occasional" 1-9%; "frequent" 10-49%; "abundant" 50-89%; "continuous" > 90%). Maximum EA frequency for each epoch was dichotomized into ≥ 1.5 Hz versus < 1.5 Hz. Poor neurologic outcome was defined as a modified Rankin Scale score of 4-6 (vs. 0-3 as good outcome) at hospital discharge.

RESULTS

One hundred and forty-three patients met study inclusion criteria. Sixty-seven patients (46.9%) had EAs. One hundred and twenty-four patients (86.7%) had poor outcome. On univariate analysis, the presence of EAs (OR 3.87 [1.27-11.71], p = 0.024) and maximum daily burden > 10% (OR 12.34 [2.34-210], p = 0.001) and > 50% (OR 8.26 [1.34-122], p = 0.035) were associated with worse outcomes. On multivariate analysis, after adjusting for clinical covariates (age, gender, NIHSS, APACHE II, stroke location, stroke treatment, hemorrhagic transformation, Charlson comorbidity index, history of epilepsy), EA presence (OR 5.78 [1.36-24.56], p = 0.017), maximum daily burden > 10% (OR 23.69 [2.43-230.7], p = 0.006), and maximum daily burden > 50% (OR 9.34 [1.01-86.72], p = 0.049) were associated with worse outcomes. After adjusting for covariates, we also found a dose-dependent association between increasing EA burden and increasing probability of poor outcomes (OR 1.89 [1.18-3.03] p = 0.009). We did not find an independent association between EA frequency and outcomes (OR: 4.43 [.98-20.03] p = 0.053). However, the combined effect of increasing EA burden and frequency ≥ 1.5 Hz (EA burden * frequency) was significantly associated with worse outcomes (OR 1.64 [1.03-2.63] p = 0.039).

CONCLUSIONS

Electrographic seizures and periodic and rhythmic patterns in patients with AIS are associated with worse outcomes in a dose-dependent manner. Future studies are needed to assess whether treatment of this EEG activity can improve outcomes.

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".

Poststroke seizures as stroke mimics: Clinical assessment and management

Epileptic seizures with postictal negative symptoms represent 20% of all suspected strokes and should be considered in the differential diagnosis of stroke in any patient presenting with an acute neurological deficit, mostly in absence of convulsions. Seizures may also occur at stroke onset, and the latter need to be promptly recognized in order to timely administer reperfusion therapies and reduce the risk of irreversible brain injury. Neuroimaging is essential in differentiating between postictal negative symptoms and deficits due to stroke. After the acute phase, poststroke seizures may worsen or cause the reappearance of neurological deficits and consciousness impairment; they can be also misinterpreted as stroke recurrence and lead to delayed treatment with antiepileptic drugs. It is mandatory to maintain a low threshold for suspecting epileptic seizures, and require appropriate electroencephalographic and neuroimaging investigations to promptly ascertain the etiology of any unexplained change in the neurological status and provide the most adequate treatment. 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".

Incidence of early poststroke seizures during reperfusion therapies in patients with acute ischemic stroke: An observational prospective study: (TESI study: "Trombolisi/Trombectomia e crisi Epilettiche precoci nello Stroke Ischemico")

INTRODUCTION

The aim of this study was to prospectively investigate the occurrence of early poststroke seizures (within 7 days of stroke) in patients undergoing reperfusion therapies (intravenous rtPA [recombinant tissue plasminogen activator] and/or endovascular thrombectomy) in comparison to those not undergoing these procedures.

METHODS

Patients aged ≥18 years with acute ischemic stroke admitted in five Italian centers were prospectively recruited. Clinical data, details on stroke type and etiology, stroke treatment, and radiological data were collected. The frequency of early poststroke seizures was assessed, and predictive factors for their occurrence were evaluated.

RESULTS

Five hundred and sixteen patients (262 in the reperfusion therapies group) were included. Stroke severity on admission and at discharge was higher among patients undergoing reperfusion therapies. Ten patients (3.8%) undergoing reperfusion therapies and 6 (2.3%) of those not receiving these treatments experienced early poststroke seizures (p = 0.45). There were no differences in any of the baseline characteristics between patients experiencing and those not experiencing early seizures.

CONCLUSION

The incidence of early poststroke seizures was overall rare, and no significant differences emerged between patients receiving and those not receiving reperfusion therapies. This article is part of the Special Issue "Seizures and Stroke".

Status epilepticus mimicking stroke recurrence

AIM OF THE STUDY

The aim of the study was to evaluate the clinical characteristics of patients with previous stroke (either ischemic or hemorrhagic), who developed status epilepticus (SE) mimicking a stroke relapse.

MATERIALS AND METHODS

We performed a retrospective cohort study of patients brought to hospital by the emergency service between December 2016 and January 2018 with a stroke code as possible candidates for intravenous thrombolysis and who had already have a previous stroke. Among them, patients admitted for negative symptoms and finally discharged with a diagnosis of SE mimicking stroke were selected and their clinical characteristics collected. All patients underwent routine blood sample analysis, head computed tomography (CT) scan and, when indicated, CT angiography and CT-perfusion imaging of the head. After admission in our stroke unit, an Electroencephalogram (EEG) was performed within 3 h in patients suspected with SE, then classified according to International League Against Epilepsy (ILAE) classification (2015). Outcome measures were SE duration, antiepileptic drugs (AEDs) administered, mortality at 12 months, Engel scale, and modified Rankin scale (m-RS) at 6 months. A second cohort included those consecutive patients discharged with a true stroke relapse in the same considered time span. Clinical characteristics of these two cohorts were compared using Mann-Whitney test or Student t-test (Confidence Interval (C.I.) 95%, p < 0.05) for continuous variable and Fisher exact test or Pearson-Chi test for dichotomic variables (p < 0.05). Survival rates were calculated, and a Log-Rank test was performed to evaluate differences in survival distribution. Only in the group with SE, m-RS at 6 months and recurrence of SE were also evaluated.

RESULTS

Eleven patients were discharged with a diagnosis of SE mimicking stroke and 65 patients with stroke relapse. Temporal lobe localization was significantly more represented in group with SE (p = 0.036) while there was no difference regarding age, sex, and National Institutes of Health Stroke Scale (NIHSS). The m-RS was significantly higher in patients with hemorrhage relapse, mainly due to the high incidence of amyloid angiopathy in this subgroup. Status epilepticus recurred in 36.4% of patients, presenting with the same clinical features, and most patients (62.5%) achieved a good seizure control at 6 months (Engel scale = 1). A difference in mortality at 12 months (all cause considered) appeared only when distinguishing strokes between ischemic and hemorrhagic (Chi-Square: 10.711, p < 0.005).

DISCUSSION AND CONCLUSION

Status epilepticus is not infrequent in patients with previous stroke and may present with negative neurological symptoms, thus mimicking a stroke recurrence. EEG should be considered as a potential diagnostic tool in the acute stroke setting, at least in patients with previous stroke. 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".

Predictors of Seizure Recurrence after Acute Symptomatic Seizures in Ischemic Stroke Patients

PURPOSE

Seizure is a well-recognized complication of both remote and acute ischemic strokes. Predictors of seizure recurrence and epilepsy in patients with ischemic stroke who develop acute symptomatic seizures (ASyS) on continuous electroencephalography (cEEG) have not been well studied.

METHODS

We present a five-year retrospective study of acute and remote ischemic stroke patients who developed ASyS on cEEG. We then identified risk factors for the development of seizure recurrence.

RESULTS

Sixty-five patients with ischemic stroke and ASyS were identified and reviewed. All ASyS were noted to be nonconvulsive seizures. Clinical recurrence of seizures was identified in 19 of these patients (29.2%) at follow-up. Rate of seizure recurrence was higher in remote ischemic stroke patients (84.2%), compared to acute ischemic stroke patients (15.8%, p = 0.0116, OR 0.17, 95% CI 0.049-0.65). Sharp waves/spikes on follow-up EEG significantly correlated with seizure recurrence (p = 0.006, OR 0, 95% CI 0-0.3926). Patients discharged on ≥3 antiepileptic drugs (AEDs) were at a higher risk of having seizure recurrence (p = 0.0015, OR 0.05, 95% CI 0.0089-0.37).

CONCLUSION

We identified risk factors of seizure recurrence in patients with ASyS as remote ischemic stroke, requiring multiple AEDs, and the presence of sharp waves on follow-up EEG. This study highlights the usefulness of cEEG in evaluating patients with acute or remote strokes.

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.

The Outcome of Status Epilepticus and Long-Term Follow-Up

Objective: This study was to investigate the outcome of status epilepticus (SE) associated with antiepileptic therapy during SE and in follow-up period, risk factors including age, co-morbidities, pre-existing epilepsy, and etiology in the East-Hungarian region.

Methods: A prospective cross-sectional database was compiled from outpatient files between 2013 and 2017. Follow-up ended on 30.06.2018.

Results: One hundred and thirty five episodes (male: 68, 50.4%) were evaluated, mean age and follow-up time being 64.1 ± 13.9 years and 39.9 ± 14.2 months, respectively. Of the 89 patients with pre-existing epilepsy, 34 failed to visit the outpatient unit regularly. Case fatality rate was 25.2% and 31 patients (30.7%) died after discharge due to co-morbidities; their mean survival time was 10.44 ± 8 months. Focal, generalized and combined type epilepsies were diagnosed in 67 patients (49.6%), 47 patients (34.8%), and 21 patients (15.6%) of SE, respectively. Nine patients had non-convulsive SE (NCSE). Mean seizure-free period was 6.8 ± 6.9 months. Patients taking carbamazepine (20.9%; OR: 0.37, 95%CI: 0.16–0.82; p = 0.018), levetiracetam (27.5%; OR: 0.51, 95%CI: 0.27–0.97; p = 0.041), or valproate (11.1%; OR: 0.18, 95%CI: 0.05–0.61; p = 0.0043) were expected to achieve seizure freedom after SE. The worst outcome was linked to advanced age, etiology, new onset status epilepticus, NCSE, and focal status epilepsy.

Conclusion: This study highlights the importance of regular care and patient follow-up.

Prediction of late seizures after ischaemic stroke with a novel prognostic model (the SeLECT score): a multivariable prediction model development and validation study

BACKGROUND

Stroke is one of the leading causes of acquired epilepsy in adults. An instrument to predict whether people are at high risk of developing post-stroke seizures is not available. We aimed to develop and validate a prognostic model of late (>7 days) seizures after ischaemic stroke.

METHODS

In this multivariable prediction model development and validation study, we developed the SeLECT score based on five clinical predictors in 1200 participants who had an ischaemic stroke in Switzerland using backward elimination of a multivariable Cox proportional hazards model. We externally validated this score in 1169 participants from three independent international cohorts in Austria, Germany, and Italy, and assessed its performance with the concordance statistic and calibration plots.

FINDINGS

Data were complete for 99·2% of the predictors (99·2% for Switzerland, 100% for Austria, 97% for Germany, and 99·7% for Italy) and 100% of the outcome parameters. Overall, the risk of late seizures was 4% (95% CI 4-5) 1 year after stroke and 8% (6-9) 5 years after stroke. The final model included five variables and was named SeLECT on the basis of the first letters of the included parameters (severity of stroke, large-artery atherosclerotic aetiology, early seizures, cortical involvement, and territory of middle cerebral artery involvement). The lowest SeLECT value (0 points) was associated with a 0·7% (95% CI 0·4-1·0) risk of late seizures within 1 year after stroke (1·3% [95% CI 0·7-1·8] within 5 years), whereas the highest value (9 points) predicted a 63% (42-77) risk of late seizures within 1 year (83% [62-93] within 5 years). The model had an overall concordance statistic of 0·77 (95% CI 0·71-0·82) in the validation cohorts. Calibration plots indicated high agreement of predicted and observed outcomes.

INTERPRETATION

This easily applied instrument was shown to be a good predictor of the risk of late seizures after stroke in three external validation cohorts and is freely available as a smartphone app. The SeLECT score has the potential to identify individuals at high risk of seizures and is a step towards more personalised medicine. It can inform the selection of an enriched population for antiepileptogenic treatment trials and will guide the recruitment for biomarker studies of epileptogenesis.

FUNDING

None.

Risk factors and motor outcome of paediatric stroke patients

BACKGROUND

Childhood stroke causes significant morbidity and mortality. In this study, we aimed to define the presenting findings, causes, risk factors and motor outcomes of our patients.

METHODS

We retrospectively analysed patients aged from 1 month to 18 years who were diagnosed as having the first onset of stroke between January 2006 and December 2015. Presenting features, causes, risk factors, recurrence rate and motor outcomes were recorded. Motor outcome was evaluated by the gross motor function classification system.

RESULTS

Forty-seven children were included in the study. Thirty-eight (78.7%) children had an arterial stroke, 9 (19.1%) had a venous stroke. The median age at the time of presentation was 60 months (3-214). Thirty-two patients (68%) presented with a focal neurological sign and 9 presented with seizure (19.1%). Patients who had a venous stroke presented with more diffuse neurological symptoms than those who had an arterial stroke. At least one risk factor for stroke was identified in 74.5% of the patients; the most common causative factor was prothrombotic state seen in 16 patients (33.5%). Stroke recurred in 5 patients (10.6%); coexistence of multiple factors was a risk factor for recurrence. Presenting with seizure was not a facilitator for epilepsy. Thirty-two (68%) patients had a favourable motor outcome. Younger age (24 months versus 114 months) and presenting with focal neurological signs were related to non-favourable motor outcome.

CONCLUSION

Our cohort demonstrates that most of the children had a risk factor for stroke and have had favourable motor outcome. However, younger age and presenting with focal seizures are related to non-favourable motor outcome.

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.

Non-convulsive status epilepticus: mimics and chameleons

Non-convulsive status epilepticus (NCSE) is an enigmatic condition with protean manifestations. It often goes unrecognised, leading to delays in its diagnosis and treatment. The principal reason for such delay is the failure to consider and request an electroencephalogram (EEG), although occasional presentations have no scalp or surface electroencephalographic correlate. In certain settings with limited EEG availability, particularly out-of-hours, clinicians should consider treating without an EEG. Patients need a careful risk–benefit analysis to assess the risks of neuronal damage and harm versus the risks of adverse effects from various intensities of therapeutic intervention. Specialists in EEG, intensive care or epilepsy are invaluable in the management of patients with possible NCSE.

Do Video-EEG Monitoring Findings in ICU Patients With Acute Stroke Predict Development of Seizures and Survival During Follow-up?

PURPOSE

Ischemic or hemorrhagic stroke are among the most common causes of seizures, especially in the elderly. EEG is the only technique that can detect epileptiform abnormalities (EA) and nonconvulsive status epilepticus (NCSE), which may negatively affect recovery of these patients. Herein we aimed to investigate the potential predictive value of long-term EEG findings in terms of poststroke seizures (PSS) and survival, in stroke patients followed up in the neurological intensive care unit (NICU).

METHODS

Video-EEG reports of stroke patients (ischemic and hemorrhagic) hospitalized between 2009 and 2014 in our NICU were reviewed. Patients with <2 months of survival were excluded. Follow-up data were obtained via telephone calls or patient charts. The correlation between EEG findings and early (≤1 week) and late seizure (>1 week) occurrence, recurrent seizure development, outcome, and survival were analyzed statistically.

RESULTS

Overall 50 patients (27 female, 23 male; age, 26-85 years) were included in the final analysis. Almost 60% developed PSS (~2/3 were early). There was no difference between ischemic versus hemorrhagic stroke patients ( P = .72). Recurrent seizures were more common in the late seizure group ( P < .001). EAs occurred in one-third of the study cohort. This finding did not predict seizure development ( P = .93) or survival ( P = .61).

CONCLUSION

PSS are a frequent finding in stroke patients followed up in NICU. EAs are not uncommon, but do not predict seizure occurrence or survival.

Incidence and management of seizures after ischemic stroke

Objective:

We conducted a meta-analysis of the incidence of early and late seizures following ischemic stroke as well as a systematic review of their pharmacologic treatment.

Methods:

Observational studies that reported incidence of seizures following ischemic stroke and those that reported treatment response to any particular antiepileptic drugs (AEDs) were included. Risk of bias was assessed by predefined study characteristics. Random effects meta-analysis was conducted for all studies where data were available for the incidence of early and late stroke-related seizures. Heterogeneity was measured with I2 statistic and sensitivity analyses were performed using prespecified variables. A qualitative synthesis of studies reporting use of AEDs for stroke-related seizures was performed.

Results:

Forty-one studies from 10,554 articles were identified; 35 studies reported incidence of stroke-related seizures and 6 studies reported effects of specific AEDs. Most studies were of low to moderate quality. Rate of early seizures was 3.3% (95% confidence interval 2.8%–3.9%, I2 = 92.8%), while the incidence of late seizures or epilepsy was 18 per 1,000 person-years (95% confidence interval 1.5–2.2, I2 = 94.1%). The high degree of heterogeneity could not be explained from the sensitivity analyses. For management of stroke-related seizures, no single AED was found to be more effective over others, though newer AEDs were associated with fewer side effects.

Conclusions:

The burden of stroke-related seizures and epilepsy due to ischemic stroke is substantial. Further studies are required to determine risk factors for epilepsy following ischemic stroke and optimal secondary prevention.

The use of routine EEG in acute ischemic stroke patients without seizures: generalized but not focal EEG pathology is associated with clinical deterioration

PURPOSE

Specialized electroencephalography (EEG) methods have been used to provide clues about stroke features and prognosis. However, the value of routine EEG in stroke patients without (suspected) seizures has been somewhat neglected. We aimed to assess this in a group of acute ischemic stroke patients in regard to short-term prognosis and basic stroke features.

METHODS

We assessed routine (10-20) EEG findings in 69 consecutive acute ischemic stroke patients without seizures. Associations between EEG abnormalities and NIHSS scores, clinical improvement or deterioration as well as MRI stroke characteristics were evaluated.

RESULTS

Mean age was 69 ± 18 years, 43 of the patients (62.3%) were men. Abnormal EEG was found in 40 patients (58%) and was associated with higher age (p = 0.021). The most common EEG pathology was focal slowing (30; 43.5%). No epileptiform potentials were found. Abnormal EEG in general and generalized or focal slowing in particular was significantly associated with higher NIHSS score on admission and discharge as well as with hemorrhagic transformation of the ischemic lesion. Abnormal EEG and generalized (but not focal) slowing were associated with clinical deterioration ( p = 0.036, p = 0.003). Patients with lacunar strokes had no EEG abnormalities.

CONCLUSIONS

Abnormal EEG in general and generalized slowing in particular are associated with clinical deterioration after acute ischemic stroke. The study demonstrates the value of routine EEG as a simple diagnostic tool in the evaluation of stroke patients especially with regard to short-term prognosis.

Challenges in the pharmacological management of epilepsy and its causes in the elderly

Epilepsy represents the third most common neurological disorders in the elderly after cerebrovascular disorders and dementias. The incidence of new-onset epilepsy peaks in this age group. The most peculiar aetiologies of late-onset epilepsy are stroke, dementia, and brain tumours. However, aetiology remains unknown in about half of the patients. Diagnosis of epilepsy may be challenging due to the frequent absence of ocular witnesses and the high prevalence of seizure-mimics (i.e. transient ischemic attacks, syncope, transient global amnesia or vertigo) in the elderly. The diagnostic difficulties are even greater when patients have cognitive impairment or cardiac diseases. The management of late-onset epilepsy deserves special considerations. The elderly can reach seizure control with low antiepileptic drugs (AEDs) doses, and seizure-freedom is possible in the vast majority of patients. Pharmacological management should take into account pharmacokinetics and pharmacodynamics of AEDs and the frequent occurrence of comorbidities and polytherapy in this age group. Evidences from double-blind and open-label studies indicate lamotrigine, levetiracetam and controlled-release carbamazepine as first line treatment in late-onset epilepsy.

Development of epilepsy after ischaemic stroke

For about 30% of patients with epilepsy the cause is unknown. Even in patients with a known risk factor for epilepsy, such as ischaemic stroke, only a subpopulation of patients develops epilepsy. Factors that contribute to the risk for epileptogenesis in a given individual generally remain unknown. Studies in the past decade on epilepsy in patients with ischaemic stroke suggest that, in addition to the primary ischaemic injury, existing difficult-to-detect microscale changes in blood vessels and white matter present as epileptogenic pathologies. Injury severity, location and type of pathological changes, genetic factors, and pre-injury and post-injury exposure to non-genetic factors (ie, the exposome) can divide patients with ischaemic stroke into different endophenotypes with a variable risk for epileptogenesis. These data provide guidance for animal modelling of post-stroke epilepsy, and for laboratory experiments to explore with increased specificity the molecular 'mechanisms, biomarkers, and treatment targets of post-stroke epilepsy in different circumstances, with the aim of modifying epileptogenesis after ischaemic stroke in individual patients without compromising recovery.