Poststroke epilepsy: update and future directions

Abstract

Stroke is among the most common causes of epilepsy after middle age. Patients with poststroke epilepsy (PSE) differ in several respects from patients with other forms of structural-metabolic epilepsy; not least in age, age-related sensitivity to side effects of antiepileptic drugs (AEDs), and specific drug-drug interaction issues related to secondary-stroke prophylaxis. Encouragingly, there has lately been remarkable activity in the study of PSE. Three developments in PSE research deserve particular focus. First, large prospective trials have established the incidence and risk factors of PSE in the setting of modern stroke care. Stroke severity, cortical location, young age, and haemorrhage remain the most important risk factors. Second, although more studies are needed, epidemiological data indicate that the risk of PSE may be influenced, for instance, by statin treatment. Third, studies are emerging regarding the treatment and prognosis of PSE. Levetiracetam and lamotrigine may be well tolerated treatment options and seizure freedom is achieved in at least a similar proportion of patients as in other epilepsies. Furthermore, new animal models such as photothrombotic stroke gives hope of a more clear understanding of PSE epileptogenesis in the near future. In summary, PSE shows indications of maturing into an independent epilepsy research field. This review summarizes recent advances in our understanding of PSE and provides an update on management issues such as diagnosis, AED selection, and prognosis. Finally, future research challenges in the field are outlined.

Keywords: antiepileptic drugs; seizures; stroke.

Figure 1.

Risk-stratification flow chart and treatment algorithm for seizures (that are not considered acute or symptomatic for other reasons) after ischaemic stroke, intracerebral haemorrhage or subarachnoid haemorrhage. Most risk estimates are from selected observational studies often influenced by AED treatment, varying time limits for early and late seizures, and varying definitions of epilepsy. AED, antiepileptic drugs; ICH, intracerebral haemorrhage; IS, ischaemic stroke; SE, status epilepticus; HT, haemorrhagic transformation; PSE, poststroke epilepsy; SAH, subarachnoid haemorrhage; sz, seizure.