Stroke risk and outcomes in epilepsy patients: Two retrospective cohort studies based on National Health Insurance in Taiwan

Antiseizure Medications and Cardiovascular Events in Older People With Epilepsy

Importance

How epilepsy may promote cardiovascular disease remains poorly understood.

Objective

To estimate the odds of new-onset cardiovascular events (CVEs) over 6 years in older people with vs without epilepsy, exploring how enzyme-inducing antiseizure medications (EIASMs) and traditional cardiovascular risk factors mediate these odds.

Design, Setting, and Participants

This was a prospective cohort study using the comprehensive cohort of the Canadian Longitudinal Study on Aging (CLSA), with 6 years of follow-up (2015-2021, analysis performed in December 2023). The CLSA is an ongoing, national study of 51 338 adults aged 45 to 85 years at baseline who are recruited in Canada. The comprehensive cohort includes 30 097 individuals living near 1 of 11 data collection centers. Participation in the CLSA was voluntary; participation rate was 45%. Among those in the comprehensive cohort, individuals reporting no previous history of CVEs (ie, stroke, transient ischemic attack [TIA], or myocardial infarction [MI]) at baseline were excluded. No other exclusion criteria were applied. A total of 86% of participants completed follow-up.

Exposure

Lifetime history of epilepsy.

Main Outcomes and Measures

The primary outcome was new-onset CVEs over 6 years. Secondary outcomes were new-onset strokes, TIAs, and MIs. Logistic models were fitted for these outcomes as a function of epilepsy, age, sex, household income, and education level. Mediation analyses were conducted for strong EIASM use, weak EIASM use, Framingham score, Physical Activity Scale for the Elderly (PASE) score, and waist to hip ratio.

Results

Among the 30 097 individuals in the comprehensive cohort, a total of 27 230 individuals (mean [SD] age, 62.3 [10.1] years; 14 268 female [52.4%]) were included, 431 with a lifetime history of epilepsy. New-onset CVEs were more likely in epilepsy, with an adjusted odds ratio of 2.20 (95% CI, 1.48-3.27). The proportion of the effect of epilepsy on new-onset CVEs was mediated as follows by each of the following variables: strong EIASM use, 24.6% (95% CI, 6.5%-54.6%), weak EIASM use, 4.0% (95% CI, 0.8%-11.0%), Framingham score, 1.4% (95% CI, -1.6% to 4.5%), PASE score, 3.3% (95% CI, 1.4%-6.8%), and waist to hip ratio, 1.6% (95% CI, 0.4%-3.7%).

Conclusions and Relevance

Results of this cohort study reveal that epilepsy was associated with new-onset CVEs. Nearly one-third of this association can be explained by EIASMs. These findings should be considered when choosing an antiseizure medication for a person at risk for cardiovascular disease.

Comparison of Cardiovascular Outcomes and All-Cause Mortality Between Patients With and Without Epilepsy: A Systematic Review and Meta-Analysis of Observational Studies

This meta-analysis aimed to assess the all-cause mortality and cardiovascular outcomes among patients diagnosed with epilepsy. The entire process of this systematic review and meta-analysis adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines to ensure transparency and reporting completeness. A comprehensive search strategy was employed to identify relevant studies in electronic databases, including PubMed, Embase, and the Cumulative Index of Nursing and Allied Health Literature (CINAHL), from January 1, 2010, to January 15, 2024. Outcomes assessed in this meta-analysis included all-cause mortality, cardiovascular mortality, stroke, myocardial infarction, and arrhythmias. A total of 12 studies were included in this meta-analysis with a pooled sample size of 7,026,313. The majority of included studies were conducted in Taiwan (n=4). Our study revealed that individuals with epilepsy faced a higher risk of all-cause mortality, cardiovascular mortality, and stroke. Although there was a higher incidence of myocardial infarction and arrhythmias among epilepsy patients, this disparity did not reach statistical significance. There is a need for future research to explore the impact of epilepsy types, antiepileptic drugs, and lifestyle factors on cardiovascular outcomes.

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.

Neuropathologic changes associated with stereoelectroencephalography depth electrode placement

BACKGROUND

The aim of this study was to detail the neuropathologic changes resulting from the surgical placement of stereoelectroencephalography (SEEG) leads in an initial small group of epilepsy cases and to raise awareness of this iatrogenic pathology, especially to those medical providers who specialize in the care of epilepsy patients.

METHODS

Five consecutive patients who underwent epilepsy resection surgery following SEEG monitoring at OSF Saint Francis Medical Center were included in our report. Resection specimens were examined grossly and entirely submitted for microscopic evaluation by a neuropathologist. Seizure-related pathologies, as well as histologic changes related to SEEG electrode placement, were documented.

RESULTS

The patient cohort included two females and three males, with an age range of 9 to 47 years. Neuropathologic examination revealed one or more seizure-related pathologies in each patient's resection specimen. In addition, all brain resection specimens showed multiple microinfarcts, which appeared to correlate with the placement and size of SEEG electrodes. Patchy leptomeningeal chronic inflammation was also seen in most cases.

CONCLUSIONS

SEEG electrode placement is an effective procedure for determining epileptogenic regions and guiding subsequent resection surgeries in medically refractory epilepsy. Multiple microinfarcts and chronic inflammation are commonly seen in brain resection specimens following SEEG electrode insertion, but studies detailing these iatrogenic histopathologic changes are lacking. The clinical significance and long-term implications of multiple small foci of electrode-induced injury that remain in the patient's brain after resection of the epileptogenic focus are unknown and may provide a welcome area for future study.

Epilepsy-Heart Syndrome: Incidence and Clinical Outcomes of Cardiac Complications in patients with Epilepsy

The risks of cardiovascular events (CVEs) in people with epilepsy (PWE) are not well understood. To establish the short- and long-term burden of CVEs in PWE. Electronic health records from a global federated health research network (TriNetX) were used to establish a cohort of PWE. Primary outcomes were: (1) the proportion of people experiencing a composite outcome of cardiac arrest, acute heart failure (HF), acute coronary syndrome (ACS), atrial fibrillation (AF), severe ventricular arrhythmia or all-cause death within 30 days of a seizure; and (2) the 5-year risk for a composite outcome of ischemic heart diseases, stroke, hospitalization, or all-cause death in the PWE experiencing early CVEs. Cox-regression analyses with propensity score matching was used to produce hazard ratios (HRs) and 95% confidence intervals (CI). In 271,172 PWE (mean age 50 ± 20 years; 52% females), the 30-day risk of CVEs following seizure was: 8.7% for the composite outcome, 0.9% for cardiac arrest, 0.8% for HF, 1.2% for ACS, 4.1% for AF, 0.7% for severe ventricular arrhythmias, and 1.6% for all-cause death. For the 15,120 PWE experiencing CVEs within 30 days of seizure, the 5-year adjusted risks for all composite outcomes measured were significantly increased (overall HR: 2.44, 95% CI 2.37-2.51), ischemic heart diseases HR 3.23 (95% CI 3.10-3.36), stroke HR 1.56 (95% CI 1.48-1.64), hospitalization HR 2.03 (95% CI 1.97-2.10), and all-cause death HR 2.75 (95% CI 2.61-2.89). The large proportions of PWE with active disease that experience CVEs and the poor long-term outcome associated suggest the existence of an "epilepsy-heart syndrome."

Detailed risks and characteristics of postepilepsy stroke in non-traumatic adult-onset epilepsy

BACKGROUND

Patients with epilepsy have an increased risk of stroke. However, the detailed risk and characteristics of postepilepsy stroke have not been investigated.

METHODS

This study utilized the National Health Insurance Research Database in Taiwan. We classified adult patients with newly diagnosed epilepsy from 2003 to 2016 as the epilepsy cohort. Patients in the nonepilepsy cohort were selected with propensity score matching at a case-control ratio of 1:5. The incidence, hazard ratio (HR), period-specific HR, recurrent HR in the Wei-Lin-Weissfeld model, stroke severity index, complications, and mortality of all stroke, ischemic stroke (IS) and hemorrhagic stroke events in the two cohorts were analyzed.

RESULTS

We enrolled 23,810 patients in the epilepsy cohort and 119,050 persons in the nonepilepsy cohort. The period-specific HRs of all stroke, IS and hemorrhagic stroke peaked immediately after epilepsy diagnosis and trended downward [Adjusted HRs of all stroke: 4.88 (3.88-6.14), 4.47 (3.50-5.70), 3.17 (2.62-3.84), 2.81 (2.27-3.48), 2.81 (2.36-3.34) and 2.33 (2.07-2.62) in 0-0.5, 0.5-1, 1-2, 2-3, 3-5 and ≥5 years after epilepsy diagnosis, respectively]. The recurrent stroke HRs in the epilepsy cohort were >1 from the first [3.06 (2.71-3.34)] to the fourth events [6.33 (1.08-37.03)]. IS events in the epilepsy cohort were associated with a younger onset age, a higher IS severity index, a higher rate of urinary tract infection, a lower in-hospital mortality, while 90-day stroke mortality was similar between the 2 cohorts.

CONCLUSION

Since the increased risk of stroke in epilepsy cohort peaked immediately after epilepsy diagnosis, early implementation of prevention strategies is considered.

Risk and outcomes of diabetes in patients with epilepsy

The risk and outcomes of diabetes in patients with epilepsy remains unclear. We evaluated these risks using an epilepsy cohort analysis and a diabetes admission analysis. In the epilepsy cohort analysis, we identified 2854 patients with newly diagnosed epilepsy in 2000–2008 from the research data of National Health Insurance in Taiwan. Using Propensity-score matching by sociodemographic factors and medical conditions, we selected 22,832 people without epilepsy as a non-exposed cohort for comparison. Follow-up events of diabetes from January 1, 2000 until December 31, 2013 were ascertained from medical claims. The adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) of diabetes associated with epilepsy were calculated using multiple Cox proportional hazard models. In the diabetes admission analysis, we identified 92,438 hospitalized diabetes patients, 930 of whom had a history of epilepsy. Adjusted odds ratios (ORs) and 95% CIs of adverse events after diabetes associated with previous epilepsy were calculated using multiple logistic regressions. The adjusted HR of diabetes in the cohort with epilepsy was 1.31 (95% CI 1.14–1.50) compared to the non-epilepsy cohort. Previous epilepsy was associated with post-diabetes adverse events, such as pneumonia (OR 1.68, 95% CI 1.37–2.07), urinary tract infection (OR 1.83, 95% CI 1.55–2.16), and septicemia (OR 1.34, 95% CI 1.09–1.65). In conclusion, epilepsy was associated with higher risk of diabetes and adverse post-diabetes outcomes. Diabetes prevention and attention to post-diabetes adverse events are needed for this susceptible population.

Predicting the risk of stroke in patients with late-onset epilepsy: A machine learning approach

BACKGROUND

The goal of this cohort study was to estimate the predictors for ischemic stroke in patients with epilepsy in a large database containing data from general practitioners in Germany using machine learning methods.

METHODS

This retrospective cohort study included 11,466 patients aged ≥ 60 years with an initial diagnosis of epilepsy in 1182 general practices in Germany between January 2010 and December 2018 from the IQVIA Disease Analyzer database. The Sub-Population Optimization and Modeling Solutions (SOMS) tool was used to identify subgroups at a higher risk of stroke than the overall population with epilepsy based on 37 different variables.

RESULTS

A total of seven variables were considered important. Four co-diagnoses (diabetes, hypertension, heart failure, and alcohol dependence) were by far the strongest predictors with a combined predictive ability of more than 90%, whereby diabetes (41.4%) was the strongest predictor, followed by hypertension (35.0%) and heart failure (11.8%). The predictive importance of male gender was only 1.5%, and age was not recognized as an important predictor. Finally, the prescribed AEDs levetiracetam, with a predictive importance of 5.0%, and valproate, with 2.7%, were found to be weak predictors.

CONCLUSION

The stroke risk in patients with epilepsy was relatively high and could be predicted based on comorbidities such as diabetes mellitus, hypertension, heart failure, and alcohol dependence. Knowing and addressing these factors may help reduce the risk of stroke in patients with epilepsy.

Epilepsy, antiepileptic drugs, and the risk of major cardiovascular events

OBJECTIVE

This study was undertaken to determine whether epilepsy and antiepileptic drugs (including enzyme-inducing and non-enzyme-inducing drugs) are associated with major cardiovascular events using population-level, routinely collected data.

METHODS

Using anonymized, routinely collected, health care data in Wales, UK, we performed a retrospective matched cohort study (2003-2017) of adults with epilepsy prescribed an antiepileptic drug. Controls were matched with replacement on age, gender, deprivation quintile, and year of entry into the study. Participants were followed to the end of the study for the occurrence of a major cardiovascular event, and survival models were constructed to compare the time to a major cardiovascular event (cardiac arrest, myocardial infarction, stroke, ischemic heart disease, clinically significant arrhythmia, thromboembolism, onset of heart failure, or a cardiovascular death) for individuals in the case group versus the control group.

RESULTS

There were 10 241 cases (mean age = 49.6 years, 52.2% male, mean follow-up = 6.1 years) matched to 35 145 controls. A total of 3180 (31.1%) cases received enzyme-inducing antiepileptic drugs, and 7061 (68.9%) received non-enzyme-inducing antiepileptic drugs. Cases had an increased risk of experiencing a major cardiovascular event compared to controls (adjusted hazard ratio = 1.58, 95% confidence interval [CI] = 1.51-1.63, p < .001). There was no notable difference in major cardiovascular events between those treated with enzyme-inducing antiepileptic drugs and those treated with non-enzyme-inducing antiepileptic drugs (adjusted hazard ratio = .95, 95% CI = .86-1.05, p = .300).

SIGNIFICANCE

Individuals with epilepsy prescribed antiepileptic drugs are at an increased risk of major cardiovascular events compared with population controls. Being prescribed an enzyme-inducing antiepileptic drug is not associated with a greater risk of a major cardiovascular event compared to treatment with other antiepileptic drugs. Our data emphasize the importance of cardiovascular risk management in the clinical care of people with epilepsy.

Risk of ischaemic stroke associated with antiepileptic drugs: a population-based case-control study in Catalonia

BACKGROUND

Cerebrovascular disorders have occurred more frequently in some Central Nervous System (CNS) disorders, such as epilepsy. Some CNS drugs have been associated with increased stroke risk. Our aim was to estimate the risk of ischaemic stroke in patients exposed to antiepileptic drugs (AED).

METHODS

Population-based matched case-control study using SIDIAP database, based in electronic health records from primary healthcare from Catalonia, Spain. Cases were those patients with a registered diagnosis of first stroke during 2009-2014. Up to 10 controls were selected for each case and matched by sex, age, and geographic area and without a prior diagnosis of stroke. We considered global drug exposure to AED, past and current exposure and exposure in monotherapy to each AED.

RESULTS

2,865 cases and 19,406 controls were exposed to AED during the study period. Global exposure to levetiracetam [(OR_adj3.3, CI95 % 2.8-4.0)], phenytoin [OR_adj1.5, CI95 % 1.2-41.9)], and valproic acid [(OR_adj 1.3, CI95 % 1.1-1.6)], showed significantly association to ischaemic stroke that was also maintained with current exposure of levetiracetam [OR_adj4.1, CI95 % 3.3-5.2)] and valproic acid [OR_adj1.4, CI95 % 1.1-1.9)]. Current levetiracetam monotherapy showed a very high risk of ischaemic stroke [(OR_adj 5.1, CI95 % 3.7-6.9)].

CONCLUSIONS

Drugs used for other conditions than epilepsy (pregabalin, gabapentin) were the most used AED and both did not show a risk. Levetiracetam shows a risk for stroke even when assessed in current monotherapy. The lack of data regarding the link with diagnosis and severity in our study makes it necessary to conduct further studies to confirm or dismiss our results, focussing on levetiracetam.

Research progress on the prediction of post-stroke epilepsy

Epilepsy is a common neurological disease that not only causes difficulties in the work and life activities of patients, but also brings complex social problems. Cerebrovascular disease is currently the main cause of epilepsy in the elderly. With the increased survival rate of patients after stroke, the incidence of epilepsy after stroke has also increased. Effective prediction of epilepsy after stroke is extremely crucial for the prognosis of patients, the initiation of antiepileptic therapy and the reduction of epileptic seizures. In this review, we summarize and compare the current models for the prediction of epilepsy after stroke, including the SeLECT prediction model, Post-Stroke Epilepsy Risk Scale (PoSERS), CAVE score, electroencephalogram (EEG) prediction model, and Scandinavian Stroke Scale (SSS) score, in order to provide reference for clinical practice and future research. Prediction models can be selected based on the clinical classification of cerebrovascular events. The SeLECT score prognostic model is a better choice for ischemic stroke, especially for the exclusive prediction of mild post stroke epilepsy. The CAVE score model is suitable for intra-cerebral hemorrhage patients. It is simple and offers high correlation between the risk factors and epilepsy. The PoSERS score simultaneously predicts ischemic and hemorrhagic stroke, and is superior to other methods in specificity as well as positive and negative prediction rate. The SSS score, which only measures stroke severity, is not strictly considered as a mature predictor, but it can be used as a first step screening tool. A growing number of large studies are under the way to identify risk factors of poststroke epilepsy (PSE) and to improve the inclusion of predictive indicators. New and advanced findings by EEG recordings may further improve the prediction of PSE.

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.

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".