Elsevier

Epilepsy Research

Volume 108, Issue 10, December 2014, Pages 1806-1816
Epilepsy Research

Risk factors for post-stroke seizures: A systematic review and meta-analysis

https://doi.org/10.1016/j.eplepsyres.2014.09.030Get rights and content

Highlights

  • Stroke severity was a significant predictor for post-stroke seizures.

  • ICH was a significant predictor for early seizures (ES) after stroke.

  • Cerebral infarction with hemorrhage transformation could predict ES after stroke.

  • Cortical involvement was a significant predictor for late post-stroke seizures.

  • ICH and infarction contribute equally to single late post-stroke seizure onset.

Summary

Purpose

To perform a systematic review and meta-analysis to identify risk factors associated with early seizure (ES) or late seizure (LS) onset in adults following stroke.

Data sources

Electronic databases (MEDLINE and EMBASE), archives of stroke or epilepsy patients, and bibliographies of relevant articles, which were written in English.

Study selection

We included studies published since 1990 that reported the stroke and seizure outcomes of adult patients during follow-up. We independently performed title, abstract and full-text screening and resolved disagreements through discussion.

Data extraction

Two authors performed the data extraction. We recorded all possible risk factors predictive of seizure onset.

Data synthesis

We used odds ratios (ORs) or the mean difference (MD) to compare the pooled rates of seizure onset between the exposed group and the non-exposed group. All meta-analyses were performed with Review Manager Software.

Results

Intracerebral hemorrhage (OR = 1.88, 95% CI = 1.43–2.47), cerebral infarction with hemorrhagic transformation (OR = 3.28, 95% CI = 2.09–5.16), stroke severity (OR = 3.10, 95% CI = 2.00–4.81, p < 0.01, I2 = 0%; MD = 3.98, 95% CI = 1.06–6.90, p < 0.01), and alcoholism (OR = 1.70, 95% CI = 1.23–2.34, p < 0.01) were associated with a significantly greater probability of ES occurrence. There were significant effects of cortical involvement (OR = 2.50, 95% CI = 1.93–3.23) and stroke severity (MD = 5.72, 95% CI = 4.23–7.22, p < 0.01, I2 = 0) on LS onset. However, there was no significant difference in the probability of single LS episode between patients with intracerebral hemorrhage and infarction stroke (OR = 1.20, 95% CI = 0.92–1.55).

Conclusions

Evidence suggests that cortical involvement, stroke subtypes and stroke severity are significant predictors of seizure onset following stroke. However, we did not find a significant difference in the rate of onset of single LS episodes between patients with intracerebral hemorrhage and cerebral infarction.

Introduction

Cerebrovascular disease is the most common cause of acute symptomatic seizures and secondary epilepsy in adults, accounting for approximately 11% of epilepsy diagnoses (Hauser et al., 1993). Post-stroke seizures have been categorized as either early-onset seizures (ES) or late-onset seizures (LS). There are different time-based definitions of stroke-associated ES. ES are defined as those occurring within 7–30 days after stroke onset. Seizures occurring after this time window are defined as LS, which may account for the variable incidences of ES and LS across studies. Investigators have reported higher rates of disability and mortality in patients with ES (Bladin et al., 2000, Lamy et al., 2003, Arboix et al., 1997). Over the long term (de Boer et al., 2008, Lamy et al., 2003, Neau et al., 1998), LS and epilepsy not only dramatically diminish the quality of life and cause serious morbidity but also negatively affect patients’ families and the broader community. Identifying risk factors for post-stroke seizures is thus crucial for the appropriate management of patients with acute stroke.

A number of seizure predictors have been studied, including stroke subtype, size, location and severity. However, the findings of previous studies are inconsistent and occasionally contradictory. These differences are largely due to the varying recruitment criteria, such as stroke type, follow-up duration, uncontrolled use of antiepileptic drugs and different time windows for distinguishing between ES and LS.

We therefore performed a systematic review and meta-analysis of studies investigating risk factors for post-stroke seizures, which are pertinent for physicians managing patients with acute stroke.

Section snippets

Search strategy and selection criteria

We performed a comprehensive literature search of MEDLINE and EMBASE. Our search strategy involved the use of medical subject headings and text words to identify studies on seizure and stroke. The search strategy used for MEDLINE (PubMed) is described in Appendix A. We also searched the bibliographies of reviews, original articles and book chapters and consulted experts on post-stroke seizures to find other studies.

Studies were collected according to the following inclusion criteria: (1)

Results

Of the 1054 unique articles initially identified, 100 appeared to be relevant to the meta-analysis upon initial review. A total of 25 studies met our inclusion criteria for the systematic review and meta-analysis, including 9 studies with 6632 participants for the analysis of ES and 19 studies with 21,392 patients for the analysis of LS.

Study characteristics

All studies involving ES collected data prospectively and included patients suffering from both hemorrhagic and infarction strokes, with the exception of one study that only included patients with hemorrhagic stroke (De Herdt et al., 2011). The incidence of ES within 1 week after stroke ranged from approximately 3.2–6.3%, but 2 studies reported rates of 12.6% (De Herdt et al., 2011) and 17.9% (Goswami et al., 2012). The ES study characteristics are listed in Table 1.

For LS, the included studies

Discussion

According to the ILAE, seizures after stroke are classified as ES when they occur within 7 days of a stroke and as LS when they take place over 7 days after a stroke (Guidelines for Epidemiologic Studies on Epilepsy, 1993). In the current study, post-stroke epilepsy was defined according to the most recent report by the ILAE (Fisher et al., 2014), which indicated that patients with a single seizure episode associated with an enduring condition that could cause epilepsy (such as stroke) met the

Limitation

Our study design has several potential limitations. We may not have included all relevant studies despite our comprehensive search strategy. Other limitations pertain to the quality of the evidence provided by the included studies. All included studies were observational. In several studies, the onset of epileptic seizures during follow-up was reported by the family or caregivers. Moderate heterogeneity existed among the studies included in the outcome analysis.

Conclusion

The conclusions from this systematic review and meta-analysis can be summarized as follows. First, intracerebral hemorrhagic stroke, cerebral infarction with hemorrhagic transformation and alcohol intake were significantly associated with ES occurring within 7 days after stroke. Second, there was no significant difference in the probability of a single LS episode between patients with intracerebral hemorrhage and infarction stroke, but intracerebral hemorrhage may predict recurrent LS after

Acknowledgements

This work was supported by the Beijing Municipal Cultivation Program of High-Level Health Technical Personnel from the Beijing Health Bureau (No. 2011-3-029) and the Beijing Municipal Administration of Hospitals Clinical Medicine Development of Special Funding (Nos. XM201304 and ZY201305).

References (44)

  • A. Alberti et al.

    Early seizures in patients with acute stroke: frequency, predictive factors, and effect on clinical outcome

    Vasc. Health Risk Manage.

    (2008)
  • R. Arntz et al.

    Post-stroke epilepsy in young adults: a long-term follow-up study

    PLoS One

    (2013)
  • C.F. Bladin et al.

    Seizures after stroke: a prospective multicenter study

    Arch. Neurol.

    (2000)
  • G. Benbir et al.

    The epidemiology of post-stroke epilepsy according to stroke subtypes

    Acta Neurol. Scand.

    (2006)
  • B.T. Bateman et al.

    Convulsive status epilepticus after ischemic stroke and intracerebral hemorrhage: frequency, predictors, and impact on outcome in a large administrative dataset

    Neurocrit. Care

    (2007)
  • E. Beghi et al.

    Incidence and predictors of acute symptomatic seizures after stroke

    Neurology

    (2011)
  • C. Cordonnier et al.

    Influence of pre-existing dementia on the risk of post-stroke epileptic seizures

    J. Neurol. Neurosurg. Psychiatry

    (2005)
  • J. Claassen et al.

    Electrographic seizures and periodic discharges after intracerebral hemorrhage

    Neurology

    (2007)
  • P.L. Ferguson et al.

    A. population-based study of risk of epilepsy after hospitalization for traumatic brain injury

    Epilepsia

    (2010)
  • R.S. Fisher et al.

    ILAE official report: a practical clinical definition of epilepsy

    Epilepsia

    (2014)
  • V. De Herdt et al.

    Early seizures in intracerebral hemorrhage: incidence, associated factors, and outcome

    Neurology

    (2011)
  • E. Faught et al.

    Seizures after primary intracerebral hemorrhage

    Neurology

    (1989)
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    Chao Zhang and Xiu Wang contributed to this work equally.

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