Seizures in the acute stroke setting

Stroke is one of the leading causes of long-term disability. One in six people in the world will suffer a stroke in their lifetime, with the annual incidence about 117 per 100 000 person-years in developing countries. It has also been shown to be the cause of 10-15% of epilepsies, more prevalent in patients above 60 years of age. The incidence of early seizures in acute stroke ranges 3-33%, with 50-78% of the seizures occurring within the first 24 hours. Occurrence of seizures within 24 hours of stroke is associated with higher 30-day mortality, which may be a reflection of severe neuronal damage. Alteration in intracellular ion concentrations and hyper-excitability are thought to be etiologies for early seizures in acute stroke, and the increased stress on already vulnerable tissues may result in worsening of stroke symptoms. Early detection of seizures and subsequent effective treatment can prevent additional metabolic burden and damage to the blood-brain barrier, which may improve recovery and overall outcome. Clinical seizures can be recognized readily at bedside and lead to prompt medical intervention. In contrast, electrographic seizures with subtle or no clinical sign and non-convulsive status epilepticus (NCSE) may escape clinical observation and be left untreated. With the use of continuous electroencephalogram monitoring (cEEG), patients with electrographic seizures can be better identified and medically treated more quickly. In addition to electrographic seizures, the presence of isolated and periodic epileptiform patterns on electroencephalogram (EEG) suggests the need for medical treatment since up to 75% of these patients have been found to develop early post-stroke seizures. Newer anti-epileptic medications with intravenous formulation, together with traditional regimen and barbiturate, have shown promise in controlling early post-stroke seizures and possibly improving outcome.