What Does Sleep Have to Do with Epilepsy?
Epilepsy is a medical condition characterized by unprovoked, abnormal brain activity, called seizures. In contrast to an isolated seizure incident, epilepsy is diagnosed when you have two or more seizures that are at least 24 hours apart. You also have to have a healthcare provider (HCP) rule out any external causes for the seizures, such as substances or recent head trauma.
What Is a Seizure?
The seizure itself is described as uncontrolled electrical activity in the brain. The seizure’s duration, severity, symptoms, and location in the brain depend on the exact type of seizure being experienced. Seizure types vary greatly from “absence seizures” which are commonly misinterpreted as daydreaming, to “tonic-clonic seizures” which are the more well-known seizures that are characterized by jerking muscles and loss of bladder and bowel control. However, there are actually many, many more types of seizures than are well-known.
Learn about different seizure types Types of Seizures
Lack of Sleep and Epilepsy
It has long been well established that sleep and epilepsy are closely linked. Specifically, a lack of sleep has been associated with a subsequent increased risk of experiencing a seizure. The actual cause of this association is not fully understood, but it is thought that somehow this lack of sleep lowers the threshold in the brain for experiencing the abnormal electrical activity of a seizure. It’s therefore extremely important for those with epilepsy or otherwise at risk of developing seizures to ensure that they get enough well-rested sleep, in order to minimize their risk of experiencing a subsequent seizure.
Seizures During Sleep
Seizures can also occur while you are sleeping, which are known as nocturnal seizures. If you were to experience seizures only while you sleep, then you would be diagnosed with nocturnal epilepsy. Interestingly, since these seizures occur during sleep, people often do not even know they are having nocturnal seizures. The seizures also are not exclusive just to night-time sleeping but can also occur in states of drowsiness or day-time naps. Unfortunately, experiencing seizures during sleep greatly affects your quality of sleep and can lead to significant drowsiness and confusion during the day.
So how do you know if you are experiencing nocturnal seizures? Indications that you may potentially be experiencing nocturnal seizures may include waking up in the morning with:
- A bitten tongue
- Having wet the bed
- An unusual state of drowsiness and confusion
It’s also possible for your nocturnal seizure to wake you in the middle of the night. If you are epileptic and find yourself waking up suddenly in the night for an unknown reason, it may be worth speaking with your healthcare provider about the possibility that you may be experiencing nocturnal seizures.
If you and your HCP think you may be experiencing nocturnal seizures, they may ask you to stay overnight in a hospital for a sleep study. This sleep study will allow you and your brain activity to be monitored throughout the night in order to identify if you are experiencing seizures in your sleep.
Why Do Seizures Happen While You Sleep?
The reason that people have seizures while they are sleeping is because of the varying levels of brain activity throughout the sleep-wake cycle. There are 4 stages of sleep. One for REM (rapid eye movement) and three NREM (non-REM). They are determined by distinct brain acitiviy patterns.
|Stage 1 (N1)||1–5 minutes||The “dozing off” stage. Brain starts to slow down its activity with brief a period of movements (twitches) as you drift out of wakefulness.|
|Stage 2 (N2)||10–60 minutes||The body becomes more relaxed as it prepares to drift into deeper sleep. Changes include a drop in the body temperature, relaxed muslces, slowed breathing and heart rate.The body temperature drops, muscles relaxed and breathing and heart rate slowed. In this stage your brain activity gets even slower but now has short, infrequent, bursts of excitement and activity.|
|Stage 3 (N3)||20–40 minutes||Also known as deep sleep and this stage is critical to restorative sleep. This is the period of sleep required for you to wake up feeling refreshed in the morning. If you are woken up during this phase, you will feel groggy and confused. Your brain waves are the slowest during this phase, though there are still spikes of excitement.|
|Stage 4 (REM Sleep)||10–60 minutes||This is the phase of sleep in which most of your dreaming occurs. This is due to the significant uptick in brain activity. Your brain activity is similar to that of when you are awake while your body enters a temporary paralysis (atona).|
Most nocturnal seizures occur as you fall asleep, before you begin to wake up, or even just after you have woken up. This is thought to be due to the changes in brain activity that occur as you shift between phases of sleep. Since seizures are characterized by electrical disturbances, these changes in brain wave patterns can set off seizures in individuals who are already at risk.
Treatment for Sleep Seizures
Treating nocturnal seizures is important because it begins to feed into a cycle of seizure risk. Some people may only experience seizures at night and never have one happen suring the day. However, other individuals may be at risk of experiencing seizures during the day as well as during the night. In this case, the sleep deprivation that comes from nocturnal seizures may then go on to trigger daytime seizures.
The treatments for nocturnal seizures are the same as for other seizure disorders: antiepileptic medications. The most common medications prescribed to treat nocturnal seizures include carbamazepine and oxcarbazepine. Antiepileptic medications work to calm down the abnormal electrical activity in the brain. They are very effective and usually have to be taken for life to maintain long-term effective seizure control.
Learn more about medications used to treat epilepsy.
- Brain Basics: Understanding Sleep National Institute of Neurological Disorders and Stroke. (2022). Retrieved 24 September 2022, from https://www.ninds.nih.gov
- Nocturnal Seizures - Seizures during Sleep - Epilepsy Action Australia. (2022). Retrieved 24 September 2022, from https://www.epilepsy.org.au
- Nocturnal Seizures | Cedars-Sinai. (2022). Retrieved 25 September 2022, from https://www.cedars-sinai.org
- Seizures - Symptoms and causes. (2022). Retrieved 25 September 2022, from https://www.mayoclinic.org
- Lanigar S, Bandyopadhyay S. Sleep and Epilepsy: A Complex Interplay. Mo Med. 2017 Nov-Dec;114(6):453-457. PMID: 30228664; PMCID: PMC6139974.
- Lucey BP, Leahy A, Rosas R, Shaw PJ. A new model to study sleep deprivation-induced seizure. Sleep. 2015 May 1;38(5):777-85. doi: 10.5665/sleep.4674. PMID: 25515102; PMCID: PMC4402675.