A 23 year old woman visited our office and complained that she had three episodes where she lost complete control of her body for several minutes as she was about to fall asleep. During one episode, she patted her boyfriend’s back while they were in bed. During the event, she said her head was turned to one side, her right arm started shaking, and then her whole body went limp for about a minute.
At first I thought she might have sleep paralysis as she also complained that she felt very sleepy most days. Since all events occurred around the time of sleep, my differential included narcolepsy with cataplexy. Then it was discovered that she might have had some sort of seizure, which it turned out to be the case.
Nocturnal seizures usually occur during sleep transition or during level 2 non-REM (NREM) sleep. They can also occur when a patient goes into slow sleep. There are several types of seizures that can occur during sleep, including tonic-clonic, Roland epilepsy (benign focal epilepsy in childhood), petit mal seizures, and partial seizures.
Excessive fatigue can cause seizures, and sleep studies are sometimes recommended that require the patient to be sleep deprived prior to the study to confirm this diagnosis. Because healthcare providers rarely see cases of nocturnal seizures, they can be easily mistaken for parasomnias, including arousal confusion, cataplexy, and REM sleep behavior disorder.
If your patient reports episodes of losing control of their body before or during sleep, keep in mind that a seizure disorder could be causing the problem. Order a polysomnogram with a full head electroencephalogram (EEG). Since seizures are often associated with other sleep disorders, including obstructive sleep apnea, you shouldn’t be surprised if a patient has both.
Children are very prone to having seizures while they sleep, especially if they have a history of seizure disorder. There are some patients who only have nocturnal seizures and have no daytime seizures, but most patients have a history.
Patients can minimize seizures by getting adequate rest. Conversely, too much sleep can also cause seizures. Advise patients who have nocturnal seizures to have a regular bedtime and get eight hours of sleep each night. Anticonvulsant treatment is also recommended. Preliminary evidence from several small studies suggests that melatonin may be helpful in minimizing seizures.
Keep nocturnal seizure disorder in your differential when assessing sleep problems. Of course, refer patients to a sleep specialist if you are unsure about the diagnosis or want a different opinion.
Sharon M. O’Brien, MPAS, PA-C, works at Presbyterian Sleep Health in Charlotte, NC. Her main interest is in helping patients understand the importance of sleep hygiene and the health effects of sleep.
- Bazil C. “Sleep-Related Epilepsy”. Curr Neurol Neurosci Rep. 2003; 3: 167-172.
- National Sleep Foundation. “Epilepsy and Sleep.” Web site.