First seizure from sleep: Clinical features and prognosis

Area of Science:

• Neurology
• Clinical Neuroscience

Background:

• First-ever unprovoked seizures require accurate prediction of recurrence for effective patient management.
• Established predictors of seizure recurrence include prior brain insult and epileptiform abnormalities on electroencephalography (EEG).
• The role of sleep onset in seizure recurrence risk requires further investigation.

Purpose of the Study:

• To investigate the association between first-ever unprovoked seizures occurring during sleep versus while awake and seizure recurrence.
• To identify if sleep-onset seizures are an independent predictor of recurrence.
• To compare injury risk and recurrence patterns between sleep and awake seizures.

Main Methods:

• Prospective cohort study of 1312 adults with a first-ever unprovoked seizure between 2000 and 2015.
• Comparison of clinical features and outcomes for seizures occurring during sleep versus while awake.
• Survival analysis to determine independent predictors of seizure recurrence.

Main Results:

• First-ever seizures during sleep occurred in 23% of patients and had a significantly higher 1-year recurrence risk (56.9%) compared to awake seizures (44.2%).
• Seizures from sleep were an independent predictor of recurrence (HR 1.44), similar to EEG abnormalities and remote symptomatic etiology.
• Recurrences of sleep-onset seizures were also typically from sleep (76% of second seizures) and associated with lower injury rates.

Conclusions:

• First-ever unprovoked seizures originating from sleep are associated with a higher likelihood of recurrence, independent of other known risk factors.
• Subsequent seizures following a sleep-onset event are also likely to occur during sleep.
• These findings have implications for treatment decisions and patient counseling following a first seizure.