Migraine and sleep

The link

Sleep and headache are closely linked. Migraine attacks may be both caused and relieved by sleep, as well as being a cause of too much or too little sleep.

How does your body know when to sleep?

You have a circadian rhythm which lasts around 24 hours.

Your body and mind go through a range of changes over this time. It controls your sleep-wake pattern and also changes how alert you are.

Your rhythm mainly responds to changes in light. The body clock in your brain controls this. In the evening, it starts to get dark and your eyes signal this to your body clock. Your body clock then tells the brain to release the hormone melatonin. This makes you sleepy. When it gets lighter, the brain reduces the amount of melatonin it makes. This starts to wake you up. However, we each have a slightly different rhythm which is why some people are more alert in the morning and others, later.

Even within the states of sleep and wakefulness, there are faster, shorter cycles of brain activity.

Sleep in migraine

Migraine attacks are said to be more likely to occur between 04:00 and 09:00 am, which might suggest a timing mechanism that relates to sleep or circadian rhythms, or both. Lack of sleep is a well-known trigger, as is too much sleep (such as lying in at the weekend). Similarly, shift-work and jet lag can be triggers in some people, suggesting an influence of both sleep and the circadian timing system.

Excessive sleepiness may be part of the premonitory phase before a migraine attack, or a symptom following the attack. Sleep can also be very helpful during a migraine attack, and may often help stop the attack, particularly in children.

Why such a close relationship?

The balance of sleep and wakefulness, and its correct timing, relies on a finely tuned system, which is referred to as homeostasis. If too much overloads this system in favour of one state (sleep or wakefulness) versus the other, such as staying up late, having fragmented sleep, sleeping in at the weekends, or sleeping at inappropriate times relative to your body clock (as happens in jet lag), the system will try and compensate to redress the balance.

One idea might be that a migraine attack may actually represent one of these balancing mechanisms, an extreme and abnormally over-compensating one. If for example you are sleep deprived, suffering a migraine may actually force you to keep still and lie down in the dark, in the hope of trying to sleep as a way of ridding yourself of the migraine.

Having too much sleep may also have the opposite effect and keep you awake with a migraine on subsequent nights. Both scenarios may be a way of trying to redress both sleep pressure and circadian alignment and keep the system in equilibrium.

How can we use this to our advantage?

Clearly these mechanisms aren’t the only basis for migraine, but it is logical to think that trying to maintain a well-balanced sleep-wake cycle may make triggering a migraine attack less likely. It is therefore perhaps important for people with migraine to observe something called good sleep hygiene, which is a set of suggestions designed to keep the sleep-wake cycle, and the quality of sleep, as even as possible.

Good Sleep Hygiene

Despite some strong evidence of a close relationship between sleep and headache, there is still a lot to understand to be able to improve treatment. Good sleep hygiene is an important step to reduce migraine by developing a regular sleep pattern through these measures:

• Try to go to bed and get up at the same time each day, as sleeping during the correct phase of your circadian cycle is important.
• Understand your sleep need, including both the timing of sleep (when feels right for you to go to bed), and the duration of sleep (most adults need about 6 to 8 hours a night).
• Try and spend some time outdoors or in natural light during the daytime, as this provides an important cue to your brain the timing of the body clock.
• Try and make your sleeping environment as restful as possible, including sufficient darkness and quiet, comfortable bedding and few devices around the bed, particularly those with lights.
• Exercise, preferably before dinner rather than before bed, can be helpful as can stopping smoking as nicotine has a stimulant effect and suppresses melatonin.
• It would be sensible to recommend that you don’t use your bed for activities that could be done elsewhere (such as watching TV, studying), and try to avoid staying in bed if you are wide-awake.
• Avoiding caffeine before bed is recommended, as is avoiding alcohol, as this actually reduces the overall quality of your sleep rather than improving your sleep as is commonly assumed.