Late-onset seizures and risk of subsequent stroke: a systematic review

Cardiovascular risk factor assessment in late-onset seizures: A study protocol to assess the value of structured intervention

OBJECTIVE

A growing body of evidence suggests patients with late-onset seizures are at an increased risk of stroke, but the potential for reducing cardiovascular morbidity through risk factor screening and management is unknown. We aim to determine whether individuals with new-onset unprovoked seizures after middle age should undergo vascular risk assessment. The long follow-up needed to assess stroke risk and the known benefit of vascular risk factor modification make a standard RCT logistically and ethically challenging. Instead, we propose and have developed a protocol for a cluster project assessing the effect of vascular risk factor screening in an intervention trial as well as a cohort study.

METHODS

Participating neurology clinics will implement standard cardiovascular risk factor assessment into the routine evaluation for individuals aged ≥50 years attending their first specialized consultation after an unprovoked seizure, excluding those with progressive brain disease. The project has two interlinked components: a prospective single group trial, in which risk factor assessment is performed and subsequent management is followed for one year; and a register-based cohort study examining the long-term effects of the intervention on a system level by comparing patients attending initial consultations in the 2 years after start of the study, with patients seen in the four preceding years at the same clinics.

ANALYSIS

The primary outcome of the intervention trial is the proportion of patients receiving subsequent pharmacological treatment. The primary outcome of the cohort study is the incidence of acute stroke in the Swedish Stroke Register.

ETHICS AND DISSEMINATION

Swedish Ethical Review Authority approval (which is valid for 2 years only) will be sought when funding is obtained. The results will be disseminated through peer-reviewed scientific publications.

REGISTRATION DETAILS

The study will be registered at clinicaltrials.gov.

PLAIN LANGUAGE SUMMARY

A first seizure in a middle-aged or older person indicates a higher risk of stroke. It is not known whether investigating and treating blood pressure, blood cholesterol, or similar risk factors after a first seizure is an effective way to prevent stroke. A traditional clinical study would need too many patients and it would be unethical not to treat the control group. We have designed a study in which participating neurology departments change their practice to test and treat vascular risk factors. Patients are then compared to historic controls using registered data.

Focused review: Clinico-neuropathological aspects of late onset epilepsies: Pathogenesis

The aim of the present study was to review the current knowledge on the neuropathological spectrum of late onset epilepsies. Several terms including 'neuropathology*' AND 'late onset epilepsy' (LOE) combined with distinct neuropathological diagnostic terms were used to search PubMed until November 15, 2023. We report on the relevance of definitional aspects of LOE with implications for the diagnostic spectrum of epilepsies. The neuropathological spectrum in patients with LOE is described and includes vascular lesions, low-grade neuroepithelial neoplasms and focal cortical dysplasias (FCD). Among the latter, the frequency of the FCD subtypes appears to differ between LOE patients and those with seizure onset at a younger age. Neurodegenerative neuropathological changes in the seizure foci of LOE patients require careful interdisciplinary interpretation with respect to the differential diagnosis of primary neurodegenerative changes or epilepsy-related changes. Innate and adaptive neuroinflammation represents an important cause of LOE with intriguing therapeutic options.

Sleep apnea, hypoxia, and late-onset epilepsy: the Atherosclerosis Risk in Communities study

STUDY OBJECTIVE

Sleep apnea is associated with unexplained epilepsy in older adults in small studies. We sought to determine the relationship between sleep apnea and additional sleep characteristics and late-onset epilepsy (LOE), adjusting for comorbidities, using data from the large, prospective Atherosclerosis Risk in Communities (ARIC) Study cohort.

METHODS

We used Medicare claims to identify cases of LOE in ARIC participants. We used polysomnography data from 1309 ARIC participants who also participated in the Sleep Heart Health Study in 1995-1998, and demographic and comorbidity data from ARIC. Later risk of LOE was evaluated using survival analysis with a competing risk of death. We also used survival analysis in 2672 ARIC participants to identify the association between self-reported obstructive sleep apnea (2011-2013), and the risk of subsequent LOE.

RESULTS

Late-midlife oxygen desaturation to less than 80% during sleep was associated with subsequent development of LOE, adjusted subhazard ratio 3.28 (1.18-9.08), but the apnea-hypopnea index was not related. Participant report of diagnosis of sleep apnea in 2011-2013 was also associated with subsequent LOE, adjusted subhazard ratio 2.59 (1.24-5.39).

CONCLUSIONS

Sleep apnea and oxygen saturation nadir during sleep are associated with LOE, independently of hypertension and other comorbidities. These potentially modifiable risk factors could have large clinical implications for LOE.

Epilepsy and epileptiform activity in late-onset Alzheimer disease: clinical and pathophysiological advances, gaps and conundrums

A growing body of evidence has demonstrated a link between Alzheimer disease (AD) and epilepsy. Late-onset epilepsy and epileptiform activity can precede cognitive deterioration in AD by years, and its presence has been shown to predict a faster disease course. In animal models of AD, amyloid and tau pathology are linked to cortical network hyperexcitability that precedes the first signs of memory decline. Thus, detection of epileptiform activity in AD has substantial clinical importance as a potential novel modifiable risk factor for dementia. In this Review, we summarize the epidemiological evidence for the complex bidirectional relationship between AD and epilepsy, examine the effect of epileptiform activity and seizures on cognition in people with AD, and discuss the precision medicine treatment strategies based on the latest research in human and animal models. Finally, we outline some of the unresolved questions of the field that should be addressed by rigorous research, including whether particular clinicopathological subtypes of AD have a stronger association with epilepsy, and the sequence of events between epileptiform activity and amyloid and tau pathology.

Histopathological characterization of cerebral small vessel disease in epilepsy patients with temporal lobe epilepsy submitted to surgery: A case-control study

BACKGROUND

Cerebrovascular disease (CVD) is a major contributor to epilepsy; however, patients with epilepsy also have a significantly increased risk of stroke. The way in which epilepsy contributes to the increased risk of stroke is still uncertain and is ill-characterized in neuropathological studies. A neuropathological characterization of cerebral small vessel disease (cSVD) in patients with chronic epilepsy was performed.

METHODS

Thirty-three patients with refractory epilepsy and hippocampal sclerosis (HS) submitted to epilepsy surgery from a reference center were selected between 2010 and 2020 and compared with 19 autopsy controls. Five randomly selected arterioles from each patient were analyzed using a previously validated scale for cSVD. The presence of CVD disease imaging markers in pre-surgical brain magnetic resonance imaging (MRI) was studied.

RESULTS

There were no differences in age (43.8 vs. 41.6 years; p = 0.547) or gender distribution (female gender 60.6% vs. male gender 52.6%; p = 0.575) between groups. Most CVD findings in brain MRI were mild. Patients had a mean time between the epilepsy onset and surgery of 26 ± 14.7 years and were medicated with a median number of three antiseizure medication (ASMs) [IQR 2-3]. Patients had higher median scores in arteriolosclerosis (3 vs. 1; p < 0.0001), microhemorrhages (4 vs. 1; p < 0.0001) and total score value (12 vs. 8.9; p = 0.031) in comparison with controls. No correlation was found between age, number of years until surgery, number of ASMs or cumulative defined daily dosage of ASM.

CONCLUSION

The present study provides evidence supporting the increased burden of cSVD in the neuropathological samples of patients with chronic epilepsy.

Early Seizures during Stroke

INTRODUCTION: The connections between seizures and stroke, their characteristics and features are barely developed and also very important for the outcome. The diagnostic problem leads to ineffective treatment due to difficult selection of patients who are subject to prevention with antiepileptic drugs (AEDs) on one hand. On the other hand, is impossible to exam every stroke patient by EEG. We need an algorithm for screening indicated patients and conducting the EEG. After that we can include properly AED as a prevention. Their low frequency makes them time consuming to study. AIM: To conduct an epidemiological study of early epileptic seizures at the acute stroke phase and to derive principles for screening, diagnosis and behavior for prevention. CONTINGENT AND DESIGN: To achieve the goal we`ve researched retrospective patients, totally amounting to 656. RESULTS AND DISCUSSION: The factors identified so far in the genesis of seizures such as age, type and location of cerebrovascular accident and proximity to the cortex do not act alone, but in combination with undiscovered ones. CONCLUSIONS: There are no clear criteria to outline the rules for the AED prophylactic in patients with cerebrovascular disease (CVD). The most important indicator is the systematic assessment of the risk of seizures in the course of the disease. Patients at high risk of triggering seizures and developing epilepsy in CVDs are suitable for EEG examinations with a view to timely diagnosis and treatment.

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.

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.

Late-onset epilepsy and the risk of dementia: a systematic review and meta-analysis

BACKGROUND

Patients with dementia have higher risk of epilepsy. However, it remains not comprehensively evaluated if late-onset epilepsy (LOE) is associated with higher risk of dementia. We, therefore, performed a meta-analysis to systematically evaluate the association.

METHODS

Relevant cohort studies were identified by search of electronic databases including PubMed, Embase, and Web of Science. A randomized-effect model incorporating the possible between-study heterogeneity was used to pool the results.

RESULTS

Overall, seven cohort studies including 873,438 adults were included, and 16,036 (1.8%) of them had LOE. With a mean follow-up duration of 8.7 years, 33,727 of them were diagnosed as dementia. Pooled results showed that LOE was associated with a higher risk of dementia (risk ratio [RR] 2.39, 95% confidence interval [CI] 2.04-2.81, p < 0.001, I² = 67%). Results of subgroup analysis showed that the association between LOE and the risk of dementia was stronger in hospital-derived participants (RR 4.23, 95% CI 2.67-6.70, p < 0.001) than that in community-derived population (RR 2.25, 95% CI 1.93-2.63, p < 0.001; p for subgroup difference = 0.01). Pooled results of three studies showed that LOE was associated with a higher risk of Alzheimer's disease (RR 2.35, 95% CI 1.08-5.08, p = 0.03, I² = 85%). One study suggested a significant association between LOE and risk of vascular dementia (RR 2.0, 95% CI 1.77-2.26, p < 0.001).

CONCLUSIONS

Evidence from cohort studies suggests that LOE may be a risk factor of dementia.

Pearls and Oy-sters: De Novo Seizure and Stroke in the Elderly: The Issue of Chicken and Egg

Seizures immediately preceding the occurrence of an ischemic or hemorrhagic stroke are a rare but well documented phenomenon, for which the term "heraldic seizure" has been proposed. Cerebrovascular disease is the most common cause of epileptic seizures in elderly patients, thus screening and management of vascular risk factors should be done systematically in cases of late-onset epilepsy. MRI may help to distinguish heraldic seizure from stroke-elicited seizure by showing abnormalities confined to the cortex that spare vascular territories, increased MRA flow in the ipsilateral cerebral arteries and enhancement of the leptomeninges on postcontrast MRI. Here we present a case report that illustrates the difficulty of making the diagnosis of a heraldic seizure at onset.

Mortality in Patients With Late-Onset Epilepsy: Results From the Atherosclerosis Risk in Communities Study

OBJECTIVE

To determine the risk of mortality and causes of death in persons with late-onset epilepsy (LOE) compared to those without epilepsy in a community-based sample, adjusting for demographics and comorbid conditions.

METHODS

This is an analysis of the prospective Atherosclerosis Risk in Communities (ARIC) study, initiated in 1987-1989 among 15,792 mostly black and white men and women in 4 U.S. communities. We used Centers for Medicare Services fee-for-service claims codes to identify cases of incident epilepsy starting at or after age 67. We used Cox proportional hazards analysis to identify the hazard of mortality associated with LOE and to adjust for demographics and vascular risk factors. We used death certificate data to identify dates and causes of death.

RESULTS

Analyses included 9090 participants, of whom 678 developed LOE during median 11.5 years of follow-up after age 67. Participants who developed LOE were at an increased hazard of mortality compared to those who did not, with adjusted hazard ratio 2.39 (95% CI 2.12-2.71). We observed excess mortality due to stroke, dementia, neurologic conditions, and end-stage renal disease in participants with compared to without LOE. Only 4 deaths (1.1%) were directly attributed to seizure-related causes.

CONCLUSIONS

Persons who develop LOE are at increased risk of death compared to those without epilepsy, even after adjusting for comorbidities. The majority of this excess mortality is due to stroke and dementia.

[Epilepsy in the aged : Challenges in diagnostics and treatment]

Epilepsy is the third most frequent neurological disorder in aged patients after stroke and dementia. The incidence of epilepsy increases with age with the highest rates in patients ≥ 65 years old. Due to demographic changes the number of aged patients with epilepsy is expected to increase further in the coming years. The leading cause of new onset epilepsy in aged patients is cerebrovascular disease followed by dementia. The recognition of seizures in aged patients is often delayed. Status epilepticus occurs more frequently in aged patients and is associated with a high mortality and morbidity. Antiepileptic drug (AED) treatment of aged patients is complicated by comorbidities and polypharmacy and AEDs with a low interaction profile and high tolerability should be selected. Levetiracetam and lamotrigine are the AEDs of choice due to low interactions and good tolerability.

Autonomic Dysfunction Contributes to Impairment of Cerebral Autoregulation in Patients with Epilepsy

Patients with epilepsy frequently experience autonomic dysfunction and impaired cerebral autoregulation. The present study investigates autonomic function and cerebral autoregulation in patients with epilepsy to determine whether these factors contribute to impaired autoregulation. A total of 81 patients with epilepsy and 45 healthy controls were evaluated, assessing their sudomotor, cardiovagal, and adrenergic functions using a battery of autonomic nervous system (ANS) function tests, including the deep breathing, Valsalva maneuver, head-up tilting, and Q-sweat tests. Cerebral autoregulation was measured by transcranial Doppler examination during the breath-holding test, the Valsalva maneuver, and the head-up tilting test. Autonomic functions were impaired during the interictal period in patients with epilepsy compared to healthy controls. The three indices of cerebral autoregulation—the breath-holding index (BHI), an autoregulation index calculated in phase II of the Valsalva maneuver (ASI), and cerebrovascular resistance measured in the second minute during the head-up tilting test (CVR_2-min)—all decreased in patients with epilepsy. ANS dysfunction correlated significantly with impairment of cerebral autoregulation (measured by BHI, ASI, and CVR_2-min), suggesting that the increased autonomic dysfunction in patients with epilepsy may augment the dysregulation of cerebral blood flow. Long-term epilepsy, a high frequency of seizures, and refractory epilepsy, particularly temporal lobe epilepsy, may contribute to advanced autonomic dysfunction and impaired cerebral autoregulation. These results have implications for therapeutic interventions that aim to correct central autonomic dysfunction and impairment of cerebral autoregulation, particularly in patients at high risk for sudden, unexplained death in epilepsy.

Late-onset epilepsy predicts stroke: Systematic review and meta-analysis

OBJECTIVE

Late-onset epilepsy (LOE) is closely associated with cerebrovascular disease, acting as both a marker of cerebrovascular disease (CVD) and occurring as a direct consequence. Despite this, our understanding of LOE as a cerebrovascular phenomenon is in its infancy. LOE also appears to be a harbinger of dementia.

METHODS

A systematic review was performed to identify publications relating to LOE and identified observational studies, clinical studies, and radiological studies.

RESULTS

A meta-analysis of observational studies demonstrated that patients presenting with LOE experience an increased risk of subsequent stroke (weighted OR 3.88 (95% CI 2.76-5.46)). The additional studies demonstrated clinical and radiological evidence to support the premise that LOE is likely to reflect underlying cerebrovascular disease.

SIGNIFICANCE

Cerebrovascular disease risk factors convey increased risk of LOE and LOE can precede stroke and dementia, acting as an early marker for cerebrovascular risk. This may represent a potential point for intervention. There are a number of suggested mechanisms relating LOE to stroke; however, there is limited understanding of the natural history of LOE. Current data support the need for prospective research in order to understand the natural history of LOE and modify disease, in order to reduce the apparent sequelae of stroke and dementia.

New anti-seizure medication for elderly epilepsy patients - a critical narrative review

Introduction: The number of elderly patients with epilepsy is growing in resource rich countries due to demographic changes and increased longevity. Management in these patients is challenging as underlying etiology, co-morbidities, polypharmacy, age-related pharmacokinetic and pharmacodynamic changes need to be considered.Areas covered: Lacosamide, eslicarbazepine acetate, brivaracetam, and perampanel have been approved in the USA and Europe for monotherapy and/or adjunctive treatment of seizures in the last few years. The authors review the pharmacological properties and safety profile of these drugs and provide recommendations for their use in in the elderly.Expert opinion: There are only limited data available on more recent antiseizure medications (ASMs). Drugs with a low risk of interaction (lacosamide, brivaracetam) are preferred choices. Once daily formulations (perampanel and eslicarbazepine acetate) have the advantage of increased compliance. Intravenous formulations (brivaracetam and lacosamide) are useful in emergency situations and in patients who have difficulties to swallow. Dose adjustments are necessary for all ASMs used in the elderly with slow titration and lower target doses than in the regulatory trials. The adverse event profile does not significantly differ from that found in the general adult population.

Risk of stroke after new-onset seizures

PURPOSE

Observational cohort studies have reported a potentially increased risk of stroke in patients with epileptic seizures. Whether late-onset seizures merit primary stroke prophylaxis is not known, and more information on stroke risk is needed for the planning of RCTs. We performed a case-control study based on Swedish national registers to quantify the risk of stroke after epileptic seizures.

METHODS

Cases ≤100 years of age with a first-ever stroke 2001-2009 were identified through the Swedish Stroke Register, and stroke-free controls (matched for age and sex) were obtained from the Population Register. The National Patient Register provided information on diagnostic codes for seizures, epilepsy and comorbidities. 123 105 stroke cases and 250 506 controls were included.

RESULTS

Epileptic seizures prior to index stroke date were detected in 1559 (1.27 %) cases and 1806 (0.72 %) controls, yielding an odds ratio (95 % confidence interval) for stroke of 1.77 (1.65-1.89). ORs were similar in men and women, but higher below the age of 75. An onset of seizures in the year preceding stroke date resulted in a higher risk for stroke (OR = 2.21, 95 % CI = 1.79-2.72) compared to when more than 5 years had passed since the first seizure (OR = 1.57, 95 % CI = 1.43-1.72).

CONCLUSION

A history of epileptic seizures was associated with an increased risk of subsequent stroke. The risk seems to be particularly high in the first year following seizure diagnosis, which supports the notion that unexplained late-onset seizures may merit swift assessment of vascular risk profile. The nature of stroke prevention requires further study.

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".

Increased risk of stroke and myocardial infarction in patients with epilepsy: A systematic review of population-based cohort studies

OBJECTIVE

The objective of the study was to review the current epidemiological evidence about the relationship between epilepsy and increased risk of cardio- and cerebrovascular events.

METHODS

We systematically searched MEDLINE (from inception to 19th October 2018) to identify population-based cohort studies evaluating the risk of subsequent stroke or myocardial infarction (MI) in patients with epilepsy without history of prior cerebrovascular disease in comparison with subjects without epilepsy.

RESULTS

A total of 16,641 records were screened, and 6 studies were included. Data on the risk of subsequent stroke and MI were provided by five and two studies, respectively. The adjusted hazard ratios (_adjHRs) of subsequent ischemic stroke for patients with epilepsy ranged from 1.09 (95% confidence interval (CI): 1.00-1.19) to 2.85 (95% CI: 2.49-3.26). Two studies assessing the incidence of hemorrhagic stroke showed an increased risk in patients with epilepsy (_adjHR: 3.30; 95% CI: 2.46-4.43 and _adjHR: 2.27; 95% CI: 1.80-2.85). The _adjHRs of subsequent MI ranged between 1.09 (95% CI: 1.00 to 1.19) and 1.48 (95% CI: 1.31-1.67). Age, hypertension, MI, diabetes, hyperlipidemia, and arteriosclerosis were significantly associated with the increase in stroke risk. A gradient between the antiepileptic drug (AED) dose and risk of subsequent stroke was found. In comparison with carbamazepine (CBZ), oxcarbazepine (OXC) was associated with an increased risk of stroke and valproate (VPA) with a reduction in risk of stroke and MI, whereas no significant associations with vascular disease were found for phenobarbital (PB), lamotrigine (LMT), phenytoin (PHT), clonazepam (CLZ), and clobazam (CLB).

CONCLUSIONS

Patients with epilepsy are at higher risk of subsequent stroke and MI in comparison with subjects without epilepsy. Although individual AEDs may carry different risks of cardio- and cerebrovascular disease, the clinical relevance of the metabolic effects of the enzyme-inducing AEDs is still uncertain. This article is part of the Special Issue "Seizures & Stroke".

Long-term follow-up of post-stroke epilepsy after ischemic stroke: Room for improved epilepsy treatment

PURPOSE

To assess long-term incidence and predictors of post-stroke epilepsy (PSE) and to evaluate the antiepileptic drug (AED) treatment in a well characterized cohort of middle-aged patients.

METHODS

The study is based on the Sahlgrenska Study on Ischemic stroke, and included 1066 adult patients with first-ever or recurrent acute ischemic stroke (AIS) before the age of 70. Early seizures (ES) were defined as seizures within one week and PSE as unprovoked seizures occurring more than one week from index stroke. Cardiovascular risk factors, subtype of AIS, and stroke severity were determined at baseline. ES, PSE, treatment with AEDs, recurrent stroke and mortality were assessed through national registers and medical records. Cox regression models were used for identifying predictors of PSE.

RESULTS

Twenty-six patients (2.4 %) developed ES. After a median follow-up of 8.0 (IQR 4.1-10.9) years, 84 (7.9 %) had PSE, and 160 (15.0 %) had experienced a non-fatal recurrent stroke. Stroke location (total anterior and partial anterior circulation infarct, both P < 0.001), ES (P < 0.001), stroke recurrence (P < 0.001), artery dissection (P < 0.002), and previous coronary heart disease (P < 0.006) were independent predictors of PSE. Only 10 (11.9 %) had the first seizure more than four years after index stroke. In 24 (30 %) PSE patients, seizure control was not achieved.

CONCLUSIONS

In addition to well-known risk factors for PSE development, our data also identified stroke recurrence, artery dissection and established coronary disease. Seizure control was less common than expected and in a significant proportion of patients AEDs had not been adjusted despite continuing seizures.

Antiepileptic Drug Use and the Risk of Stroke Among Community-Dwelling People With Alzheimer Disease: A Matched Cohort Study

Background People with Alzheimer disease ( AD ) are more predisposed to seizures than older people in general, and use of antiepileptic drugs ( AED s) is more frequent. AED use has been linked to a higher risk of vascular events in the general population; however, it is not evident whether the same risk exists in people with AD . We assessed the risk of stroke associated with incident AED use among people with AD . Methods and Results The MEDALZ (Medication Use and Alzheimer's Disease) cohort includes all Finnish people who received a clinically verified AD diagnosis (N=70718) from 2005 to 2011. People with previous strokes were excluded. For each incident AED user (n=5617) one nonuser was matched according to sex, age, and time since AD diagnosis. Analyses were conducted with Cox proportional hazards models and inverse probability of treatment weighting. Compared with nonuse, AED use was associated with an increased risk of stroke (inverse probability of treatment weighting hazard ratio ( HR ), 1.37; 95% confidence interval [CI], 1.07-1.74). The risk was strongest during the first 90 days (adjusted HR , 2.36; 95% CI , 1.25-4.47) of AED use. According to stroke type, the association was with ischemic strokes (inverse probability of treatment weighting HR , 1.34; 95% CI , 1.00-1.79) and hemorrhagic ones (inverse probability of treatment weighting HR , 1.44; 95% CI , 0.86-2.43). The stroke risk of users of older AED s did not differ from that of the users of newer AED s (adjusted HR , 1.04; 95% CI , 0.71-1.53). Conclusions AED use was related to an increased risk of stroke, regardless of AED type. Our results highlight caution in AED use in this vulnerable population.

Predictors of early seizure recurrence among elderly inpatients admitted to a tertiary center: A prospective cohort study

PURPOSE

Early seizure recurrence is common among elderly inpatients and is related to increased morbidity and a longer length of hospital stay. There are few studies on the short-term outcomes of seizures in the elderly population. We aimed to identify the predictors of early seizure recurrence among elderly inpatients.

METHODS

We prospectively enrolled patients aged 60 years and older from a tertiary center who had seizures that either led to their hospital admission or occurred during hospitalization. We analyzed the demographic and hospitalization data, characteristics and etiology of seizures, and neurological and clinical comorbidities. Kaplan-Meier analysis was performed to determine the 30-day cumulative recurrence rates. The logrank test was used to analyze the risk of seizure recurrence within 30 days after the index seizure. Multivariable logistic regression analysis was used to identify risk factors for the recurrence of seizures within 30 days.

RESULTS

Overall, 109 patients (mean age: 75.9 ± 9.6 years) were enrolled. The mean age at the first-ever seizure was 74 ± 11.7 years. Unprovoked seizures occurred in 59.6% of the patients. Cerebrovascular disorders were the most prevalent etiology (52.3%). Early seizure recurrence, defined as within 30 days, occurred in 27.5% of patients. Multimorbidity was found in 95.4% of our inpatients (6.3 ± 2.3 [95% confidence interval, 5.4-7.2]), and the number of comorbidities was higher among those who had seizure recurrence than that among those who did not have seizure recurrence (p = 0.02). The probability of seizure recurrence was similar among the subgroups of patients who experienced acute seizures versus unprovoked seizures (both p = 0.03), and seizure recurrence was associated with a longer length of hospital stay (p = 0.005) compared to that of patients who did not experience seizure recurrence. After multivariate analysis, sepsis (p = 0.011), psychiatric disorders (p = 0.032), and cardiac arrhythmias (p = 0.037) were identified as risk factors for early seizure recurrence.

CONCLUSIONS

Higher multimorbidity and a longer length of stay were associated with early seizure recurrence; and sepsis, psychiatric disorders, and cardiac arrhythmias were independent risk factors for early seizure recurrence among elderly inpatients.

Postictal syndrome: The forgotten continent. An overview of the clinical, biochemical and imaging features

Postictal syndrome (PIS) encompasses the clinical, biological, electroencephalographic (EEG) and magnetic resonance imaging (MRI) signs that follow the termination of a seizure. These signs occur as soon as the epileptic discharge ends, but might remain for a substantially long period of time, making them amenable to clinical observation. As a direct consequence, neurologists and intensivists are more frequently attending patients with PIS than during their seizure. Moreover, careful PIS documentation may help physicians to diagnose epileptic seizure from other non-epileptic disorders. Careful analysis of PIS could also be helpful to better characterize the seizure (seizure subtypes, and to some extent, the localization and/or lateralization of the seizure). This article aims to review the main clinical, biological, EEG and MRI components of PIS, discuss differential diagnoses and propose a general clinical attitude, based on the acronym "WAITTT": W for "Watch", to monitor and investigate PIS in order to provide relevant information on seizure, AIT for "Avoid Inappropriate Treatment", to underscore the risk carrying out unnecessary drug injections and intensive care procedures in the setting of a self-limited symptomatology, and TT for "Take Time", to keep in mind that time remains the clinician's best ally for treating patients with PIS.

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.

Association between implementation of a code stroke system and poststroke epilepsy

Objective

We aimed to investigate the effect of a code stroke system on the development of poststroke epilepsy.

Methods

We retrospectively analyzed consecutive patients treated with IV thrombolysis under or outside the code stroke system between 2003 and 2012. Patients were followed up for at least 2 years or until death. Factors with p < 0.1 in univariate comparisons were selected for multivariable logistic and Cox regression.

Results

A total of 409 patients met the eligibility criteria. Their median age at stroke onset was 75 years (interquartile range 64–83 years); 220 (53.8%) were male. The median follow-up duration was 1,074 days (interquartile range 119–1,671 days). Thirty-two patients (7.8%) had poststroke seizures during follow-up, comprising 7 (1.7%) with acute symptomatic seizures and 25 (6.1%) with late-onset seizures. Twenty-six patients (6.4%) fulfilled the definition of poststroke epilepsy. Three hundred eighteen patients (77.8%) were treated with the code stroke system while 91 (22.2%) were not. After adjustment for age and stroke etiology, use of the code stroke system was associated with decreased odds of poststroke epilepsy (odds ratio = 0.36, 95% confidence interval 0.14–0.87, p = 0.024). Cox regression showed lower adjusted hazard rates for poststroke epilepsy within 5 years for patients managed under the code stroke system (hazard ratio = 0.60, 95% confidence interval 0.47–0.79, p < 0.001).

Conclusion

The code stroke system was associated with reduced odds and instantaneous risk of poststroke epilepsy. Further studies are required to identify the contribution of the individual components and mechanisms against epileptogenesis after stroke.

Classification of evidence

This study provides Class III evidence that for people with acute ischemic stroke, implementation of a code stroke system reduces the risk of poststroke epilepsy.

Compromised Dynamic Cerebral Autoregulation in Patients with Epilepsy

Objective

The aim of this study is to analyze dynamic cerebral autoregulation (dCA) in patients with epilepsy.

Methods

One hundred patients with epilepsy and 100 age- and sex-matched healthy controls were recruited. Noninvasive continuous cerebral blood flow velocity of the bilateral middle artery and arterial blood pressure were recorded. Transfer function analyses were used to analyze the autoregulatory parameters (phase difference and gain).

Results

The overall phase difference of patients with epilepsy was significantly lower than that of the healthy control group (p = 0.046). Furthermore, patients with interictal slow wave had significant lower phase difference than the slow-wave-free patients (p = 0.012). There was no difference in overall phase between focal discharges and multifocal discharges in patients with epilepsy. Simultaneously, there was no difference in mean phase between the affected and unaffected hemispheres in patients with unilateral discharges. In particular, interictal slow wave was an independent factor that influenced phase difference in patients with epilepsy (p = 0.016).

Conclusions

Our study documented that dCA is impaired in patients with epilepsy, especially in those with interictal slow wave. The impairment of dCA occurs irrespective of the discharge location and type. Interictal slow wave is an independent factor to predict impaired dCA in patients with epilepsy.

Clinical Trial Identifier

This trial is registered with NCT02775682.

The Progress of Epilepsy after Stroke

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Pre-stroke seizures: A nationwide register-based investigation

PURPOSE

The relationship between cerebrovascular disease and seizures is clearly illustrated by poststroke epilepsy. Seizures can also be the first manifestation of cerebrovascular disease and case-control studies have demonstrated that seizures carry an increased risk of subsequent stroke. Thus, seizures could serve as a marker for vascular risk that merits intervention, but more data is needed before proper trials can be conducted. The occurrence of pre-stroke seizures has not been assessed on a national scale. We asked what proportion of strokes in middle-aged and elderly patients was preceded by seizures.

METHODS

All patients over 60 years of age with first-ever stroke in 2005-2010 (n=92,596) were identified in the Swedish stroke register (Riksstroke) and cross-sectional data on a history of a first seizure or epilepsy diagnosis in the ten years preceding stroke were collected from national patient registers with mandatory reporting.

RESULTS

1372 patients (1.48%) had a first seizure or epilepsy diagnosis registered less than ten years prior to the index stroke. The mean latency between seizure and stroke was 1474days (SD 1029 days).

CONCLUSIONS

Seizures or epilepsy preceded 1.48% of strokes in patients >60years of age. Based on recent national incidence figures, 5-20% of incident cases of seizures or epilepsy after 60 years of age could herald stroke, depending on age group. These proportions are of a magnitude that merit further study on how to reduce the risk of stroke in patients with late-onset seizures or epilepsy.

Excess mortality and hospitalized morbidity in newly treated epilepsy patients

OBJECTIVE

To assess the burden of mortality and hospitalized morbidity in newly treated epilepsy patients.

METHODS

We extracted relevant data of patients with newly treated epilepsy between September 16, 2005, and September 15, 2010, from the data repository covering all public hospitals in Hong Kong. Patients were followed up until September 15, 2011. Mortality and hospitalized morbidity were assessed, stratified by baseline comorbidities, number of antiepileptic drugs (AEDs) used, and treatment with enzyme-inducing AEDs (EIAEDs). Mortality was compared to the age- and sex-specific general population in Hong Kong.

RESULTS

Of the 7,461 newly treated epilepsy patients (55% male; median age 60 years), 2,166 (29%) died during the study period. The standardized mortality ratio was 5.09 (95% confidence interval [CI] 4.88-5.31), and was higher among those with physical or psychiatric baseline comorbidity (5.46; 95% CI 5.22-5.71) than those without (3.28; 95% CI 2.87-3.73). Standardized hospitalization ratio was 6.76 (95% CI 6.70-6.82). Baseline physical comorbidity-free patients (n = 3,514) exhibited higher risk of developing stroke (standardized incidence ratio [SIR] 4.96; 95% CI 4.19-5.84) and ischemic heart disease (SIR 4.18; 95% CI 3.54-4.91), and male patients had elevated risk of developing cancer (SIR 2.30; 95% CI 1.75-2.97). Patients treated with EIAEDs had higher risk of being subsequently recorded with new physical comorbidities than those with non-EIAEDs (relative risk [RR] 1.48; 95% CI 1.19-1.85), especially for cerebrovascular disease (RR 1.78; 95% CI 1.14-2.77).

CONCLUSIONS

Newly treated epilepsy patients bear excess mortality and hospitalization risks. They have higher risk of developing stroke, ischemic heart disease, and cancer. Treatment with EIAEDs was associated with increased overall morbidity.

The causes of new-onset epilepsy and seizures in the elderly

With increasing age, the prevalence and incidence of epilepsy and seizures increases correspondingly. New-onset epilepsy in elderly people often has underlying etiology, including cerebrovascular diseases, primary neuron degenerative disorders, intracerebral tumors, and traumatic head injury. In addition, an acute symptomatic seizure cannot be called epilepsy, which manifests usually as a common symptom secondary to metabolic or toxicity factors in older people. In this review, we have mainly focused on the causes of new-onset epilepsy and seizures in elderly people. This knowledge will certainly help us to understand the reasons for high incidences of epilepsy and seizures in elderly people. We look forward to controlling epileptic seizures via the treatment of primary diseases in the future.

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.