Neuropsychiatric Symptoms of Epilepsy

8 Epilepsy and Sleep: Close Connections and Reciprocal Influences
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awake EEG could be normal, whereas EEG after sleep deprivation and during early
sleep stages or soon after awakening may disclose generalized spike-and-wave discharges.
The myoclonic jerks characteristic of juvenile myoclonic epilepsy (JME),
another type of IGE, usually occur after awakening and are often precipitated by
sleep deprivation [ 18 ]. Sleep is an important activating state of seizures in Benign
Epilepsy of Childhood with Centrotemporal Spikes (BECT) [ 19 ], a form of idiopathic
(with age-related onset) focal epilepsy. Drowsiness is a strong trigger of the
typical EEG paroxysmal abnormalities on the centrotemporal areas and spikes
appear only during sleep in about one third of patients.
Focal seizures in lesional or cryptogenetic partial epilepsy may have a random
occurrence. However, seizures in some patients may adopt a more regular circadian
rhythm during the illness, irrespective of the clinical form, and tend to concentrate
preferentially during sleep.
Infantile spasms also occur more frequently in the period preceding or just following
sleep, whereas they rarely occur during non-REM sleep and never during
REM. Generalized tonic seizures associated with Lennox–Gastaut syndrome occur
more frequently in clusters upon awakening.
Patients with sleep disorders may exhibit an increase in seizure frequency and
more difficulty with seizure control secondary to sleep fragmentation. Patients with
obstructive sleep apnea syndrome or restless legs syndrome may have poor seizure
control. Patients with altered sleep patterns may also experience increased seizures.
Central nervous system abnormalities that alter or interrupt circadian pathways may
also affect sleep and seizure control.
Epilepsy and Sleep Disorders
Sleep disorders or sleep-related physiological events frequently coexist in patients
with epilepsy and may mimic epileptic seizures. Prompt recognition of phenomena
mimicking epilepsy is vital to prevent patients undergoing unnecessary and costly
investigations, and clinicians instigating potentially harmful therapeutic regimens.
Furthermore, it is important to recognize these cases because treatment of the sleep
disorder may contribute to seizure control by decreasing sleep disruption [ 6 , 20 ].
Sleep-Related Breathing Disorders
Obstructive Sleep Apnea (OSA)
Obstructive sleep apnea (OSA ) is characterized by snoring associated with repetitive
episodes of upper airway obstruction or cessation of breathing during sleep, associated
with blood oxygen saturation reduction and consequent arousals and sleep disruption
[ 21 ]. Awakenings with feelings of suffocation, fear due to sleep apnea, and