The association of epileptic seizures with sleep was noted over a century ago. Daytime forms of seizures (in wakefulness) had 40% of patients, nighttime (during sleep) – 25% of patients. In other cases, seizures occurred independently of sleep or wakefulness. The relationship between the course of epilepsy and the movement of the lunar phases is noted. In some people with epilepsy, the greatest number of seizures occurs on the first day after the new moon and full moon. A number of authors have described “sleepy” epilepsy with seizures occurring exclusively during sleep.
Sleep epilepsy is manifested more often by partial generalized seizures, sensory phenomena are noted in a seizure, foci located in the right hemisphere dominate. The prognosis of the disease with seizures occurring during sleep is more favorable in the case of generalized tonic-clonic seizures than in the case of partial seizures.
Epilepsy of wakefulness is equally common in boys and girls, while sleep-wake epilepsy is 1.5 times more common in males.
There are a number of sleep-related epileptic syndromes. These include: idiopathic generalized epilepsy with tonic-clonic seizures, absences , juvenile myoclonic epilepsy, infantile spasms, benign partial E with centrotemporal adhesions, benign partial E of childhood with occipital paroxysms. Recently, interest has increased in autosomal dominant frontal epilepsy with nocturnal paroxysms and Landau- Kleffner syndrome .
Epilepsy significantly affects sleep patterns. Sleep disturbances can occur in the pattern of prodromal epileptic symptoms. Deep sleep following a generalized seizure is possibly a defense mechanism. Paroxysmal, sometimes unexplained awakenings during sleep may be the only manifestation of nocturnal seizures. As a result, the patient is mistakenly diagnosed with sleep disorders. These paroxysmal awakenings can occur in the presence of a deep epileptic focus, especially in frontal epilepsy.
Drugs such as barbiturates and benzodiazepines, diphenine and carbamazepine can cause a decrease in REM sleep. However, some of them can have a positive effect on sleep patterns. With regard to valproic acid, there are no unambiguous data: one study did not reveal a significant effect on the structure of sleep, another showed an increase in delta sleep, and the third showed a reduction in REM sleep.
In 1937, just 9 years after the discovery of electroencephalography (EEG), Gibbs FA, Gibbs EL and Lenoex WG wrote that “recording an EEG in one minute of superficial sleep provides more information for diagnosing epilepsy than an hour of waking “. This is due to the fact that epilepsy as a disease uses the same morphological and biochemical substrates for its development as the physiological sleep of a healthy person. Therefore, sleep research provides a much deeper insight into the essence of the epileptic process.
The study of nighttime sleep has a special role in situations where the cause of the disease is unclear. For example, a person regularly loses consciousness and seizures occur. There are many cardiovascular and neurological diseases that can produce these symptoms. The study of nocturnal sleep allows us to resolve the emerging dilemma: are these seizures epileptic or non-epileptic . The prognosis, treatment and social adaptation of patients depend on this.