The bidirectional relationship between sleep and epilepsy has been documented for many years. Not only do sleep patterns influence seizures within epilepsy, but the condition is associated with poor sleep quality.

We will disentangle the interactions between sleep and epilepsy, examining factors such as epilepsy medications and additional sleep disorders that influence this relationship. Lastly, we will recommend simple lifestyle modifications to improve sleep and seizure triggers.

Epilepsy

Epilepsy is a common disorder that affects over 50 million people around the world. In fact, approximately 5 million people worldwide are diagnosed with epilepsy every year. It is a disorder characterised by reoccurring seizures in an individual. While seizures can occur due to various causes, epilepsy is specifically diagnosed in individuals who experience multiple unexplained seizures in a period longer than 24 hours.

Seizures are caused by excessive electrical activity within the brains of epilepsy patients. This leads to brief episodes of involuntary movement, either in specific body parts or across the whole body. Additionally, a seizure can also result in loss of consciousness and loss of control of an individual’s bowel or bladder functions. Sensory processing may be momentarily disturbed, affecting vision, hearing or taste. A seizure can range in both frequency and duration based on the individual and the current severity of their epilepsy.

The relationship between sleep and epilepsy

The relationship between sleep and epilepsy has long been established. It was first documented among the Greeks when Aristotle first noted a connection between sleep and seizure behaviours. This relationship is complex and wide-ranging as sleep and epilepsy both affect each other in various ways. Here, we will explore the effect of sleep on epilepsy patients as well as the effect of seizures on individuals who suffer from epilepsy.

Why are sleep and epilepsy interconnected?

The brain’s electrical and hormonal activities are constantly fluctuating throughout the day. These changes are closely linked to an individual’s sleep-wake cycles. As a result, altered or disturbed sleeping behaviours can trigger abnormal electrical activity in the brain, leading to seizures in patients with epilepsy.

Additionally, individuals with epilepsy often have trouble falling or staying asleep. This is because epilepsy patients tend to spend more time in lighter stages of sleep and less time in the sleep stages associated with deep rest and dreaming, such as N3 and REM sleep.¹

General differences in brain activity are also observed in people with epilepsy. Their brain activity displays less ‘sleep spindle’ activity, which are the electrical patterns linked with learning, memory and sustained sleep. This indicates that the quality of sleep is also lower in individuals with epilepsy compared to the general population.

Disturbed sleep as a trigger for seizures

Sleep deprivation is a known trigger for seizures.² It is often a common cause of a person’s first seizure, where a sustained period of poor sleep or a single all-nighter triggers a seizure episode. This is not only true for people diagnosed with epilepsy but also triggers one-off seizures in people without epilepsy.

Many factors can result in disturbed or poor sleep. These can either be linked to epilepsy itself or can be caused by other factors or sleep disorders. Below are common causes of disturbed sleep and their relationship with increased frequency or severity of seizures in epilepsy patients:

Epilepsy-related causes of disturbed sleep

• Having nighttime/nocturnal seizures: As will be explained later in the article, epilepsy seizures that occur before or during sleep can be detrimental to sleep quality. These are more prevalent in certain types of epilepsy, which will be described later.
• Side effects of seizure medications: Certain seizure medications are associated with increased daytime sleepiness and difficulty falling asleep. Healthcare professionals may recommend altering the timing of medication and the type of medication prescribed.³

Other causes of disturbed sleep

• Insufficient sleep or poor-quality sleep: Most people require around 8 hours of sleep per night, with women typically requiring an additional hour compared to men. In addition to the total time spent asleep, the quality of sleep is also crucial. This describes sufficient amounts of sleep, sleeping through the night, and waking up feeling rested. Daytime sleepiness is a common sign of insufficient or poor sleep.
• Eating habits: Certain eating behaviours have been linked to decreased sleep quality. Examples include eating right before bed or eating large meals in the evening. Drinking caffeine or alcohol is also detrimental to sleep.
• Low mood: Poor sleep is linked to mood disorders, such as depression and anxiety.

Sleep disorders linked with seizures/epilepsy⁴

• Sleep apnea: Most prevalent in middle-aged men, sleep apnea manifests as complete or partial obstruction of the airways during sleep. This often leads to loud snoring and waking numerous times throughout the night, leading to increased daytime sleepiness.
• Restless legs syndrome (RLS): This is when a burning or itching sensation is felt in the legs when an individual is still, causing the urge to move the legs to alleviate the discomfort. It can lead to difficulty falling asleep which decreases sleep quality and increases daytime sleepiness. Additionally, it is associated with periodic limb movements, which are involuntary movements in the arms or legs that can jar individuals from sleep.
• Insomnia: Insomnia refers to the difficulty of falling or remaining asleep. It can be experienced short-term, mainly due to stress or low mood, or for longer periods of time. Causes of long-term insomnia include depression and anxiety, which are also more common in individuals with epilepsy.

Nocturnal/Sleep-associated seizures

Research has shown that over 1 in 10 people with epilepsy only experience seizures while asleep or upon waking from sleep. These are known as nocturnal seizures.

Unfortunately, nocturnal seizures can further disrupt the sleep of an individual, exacerbating disturbed sleep as a trigger for more nocturnal or daytime seizures. Nocturnal seizures often wake individuals and prevent them from entering the REM stage of sleep associated with deep rest.⁵ It can also lead to inconsistent sleeping patterns and quality over weeks or months, resulting in poor sleep habits and behaviours over time.⁶

Management

Improving sleep quality

By promoting better sleep quality and behaviours, seizures and symptoms of epilepsy may improve. Below are simple but effective ways to improve sleep:

• Exercise: Engage in regular exercise and avoid cardio or high-intensity workouts in the evening.
• Sleep hygiene before bed: Few hours before you sleep, avoid looking at electronic screens or eating large meals. Instead, consider taking warm showers or engaging in relaxing activities like reading to help your mind wind down for sleep.
• Diet: Avoid eating large amounts right before sleep. Avoiding alcohol and caffeine in the afternoon can also improve sleep quality.
• Reduce stress and work before sleep: Avoid working in your bedroom or in bed. Instead, take your mind off work and stress before sleep by winding down or meditating.

Consult health professionals about medications

Both daytime sleepiness and poor sleep can be side effects of epilepsy medications. Consulting your healthcare professional about the side effects and exploring alternatives to your current epilepsy medication may lead to improved sleep.

Treat epilepsy-related sleep disorders

Epilepsy has been associated with sleep disorders such as sleep apnea, restless leg syndrome, and insomnia. Other mental health issues, such as depression and anxiety are also more common among individuals with epilepsy which can also be detrimental to sleep. Seeking healthcare advice and treatment for these related disorders can improve sleep and, in turn, decrease the frequency and severity of epilepsy seizures. Both medication and lifestyle modifications can improve these epilepsy-associated conditions depending on their severity.

Conclusion

In conclusion, the relationship between epilepsy and sleep is bidirectional. Up to 15% of epilepsy patients experience seizures primarily before or during sleep. This may be due to the unique electrical activity of the brain during these periods. Conversely, disrupted or poor sleep can also increase the frequency or severity of seizures in individuals with epilepsy. This emphasises how important sleep management is in epilepsy patients. Improvement can be achieved through healthy sleep habits, epilepsy medications, and management of other conditions associated with epilepsy.