Seizures Following Ischemic Stroke: Frequency of Occurrence and Impact on Outcome in a Long-Term Population-Based Study

Abstract

Background & Purpose Seizures are a known complication of ischemic stroke. This study assesses the long-term incidence and characteristics of post-stroke seizures in a well-defined population. Methods Utilizing the Rochester Epidemiology Project medical record linkage system, we identified all incident cases of ischemic stroke (IS) among Rochester, MN residents from 1990-1994, and followed the patients in the comprehensive medical record through March 2014. All patients with post-stroke seizures were identified, and data regarding incident IS, seizures, and status at last follow-up were analyzed. Results We identified 489 patients with first IS. Mean follow-up was 6.5 (SD 6.3) years. New onset seizures occurred in 35 patients (7.2%). Patients with post-stroke seizure did not differ from those without in terms of IS etiologic subtype (p=0.44) or IS risk factors (p>0.05). Early seizures (within 14 days of index stroke) developed in 14 patients (40%), the majority within the first 24 hours (n=9; 64.3%). The median time of seizure onset for the remaining 21 patients was 13.8 months. Functional outcome, as measured by modified Rankin scale, was worse following development of post-stroke seizures (mean mRS 2.9 after IS, 3.3 following index seizure; p=0.005), and mortality was higher as well, even after adjusting for IS etiologic subtype (HR 1.52; 95% CI 1.07-2.16; p=0.02). Conclusion Development of post-stroke seizures is an infrequent, but significant complication of ischemic stroke, portending a worse short-term functional outcome and a higher long-term mortality rate. Seizure occurrence did not differ based on IS etiologic subtype or stroke risk factors.

Poststroke epilepsy: update and future directions

“…Other studies on small populations report varying results [Paolucci et al 1997;Bryndziar et al 2015]. Taken together, there may be room for improvement in management that should aim for seizure freedom in the same manner as in other forms of epilepsy.…”

“…In the largest study to date that was performed in the UK and followed 3310 patients with newly diagnosed stroke for an average of 3.8 years, the 10-year risk of PSE was calculated to be 12.4% [Graham et al 2013]. In a smaller, but population-wide study, 4.4% of 481 patients developed late seizures over an average follow-up period of 6.3 years [Bryndziar et al 2015]. Another study on 1020 patients reported a 2-year risk of 8.2% [Jungehulsing et al 2013].…”

“…Epilepsy prognosis PSE is often described as an easily manageable form of epilepsy, where monotherapy suffices to control seizures [Silverman et al 2002;Bryndziar et al 2015]. If so, recent real-life data indicate that current management of PSE may not be ambitious enough.…”

Comment on Epilepsy in cerebrovascular diseases: Review of experimental and clinical data with meta‐analysis of risk factors

“…4 Other retrospective studies exist, but report older cases and may not reflect current clinical practice. 5,6 The findings in real-life observational studies contrast markedly with the excellent efficacy of different AEDs seen in monotherapy clinical trials. In clinical trials cited in the review, seizure freedom rates of >70% are not uncommon.…”

The Potential Role of MicroRNA-124 in Cerebral Ischemia Injury

“…Moreover, ischemia-induced BBB disruption, an anatomic alteration after cerebral ischemia [1], is also a fundamental catalyst for the initiation of epilepsy [134]. A population-based study of seizure revealed that cerebral infarction was a common cause of epilepsy [135,136], and patients with a disabling cortical infarct are more likely to have epilepsy after ischemic stroke [137]. Though the mechanisms underlying epileptogenesis remain uncertain, inflammation, mitochondrial dysfunction, and oxidative stress are emerging as the major factors contributing to epileptogenesis [138].…”