One of the worst things to wake up to has to be a migraine. Talk about a bad start to the day! But why is waking up to a migraine so common? What are the links that we know of between sleep and migraines?
The most common time for a migraine to occur, according to the American Migraine Foundation, is early in the morning. For one thing, most over-the-counter medications will have worn off after 4-8 hours (i.e. while you were sleeping) so their protection will be gone.
However, there are some migraines which are specifically characterised by sleep. One of these is the hypnic headache, also known informally as ‘alarm clock’ headaches. The hypnic headache is a rare headache disorder, usually affecting those aged over 50, in which the headaches only occur during sleep (typically between 1 and 3 am) and wake the sleeper.
Hypnic headaches typically last between thirty and sixty minutes, but can be anywhere from fifteen minutes to six hours in duration. Most commonly they occur without any symptoms other than the head pain, but some sufferers have reported other symptoms such as a blocked nose or watering eyes, and light or sound sensitivity as well. (Oddly enough, the recommended initial treatment for these kinds of headaches involves drinking caffeine!)
Another form of migraine that may develop during sleep is cluster headaches. They usually occur within an hour or two of falling asleep, occur around or behind one eye, and last between fifteen minutes and three hours.
Sleep plays a big role in migraines and their frequency. Getting too little sleep or too much sleep are two common triggers of migraine attacks. The reason why too much sleep can trigger migraines is not certain. It’s thought to involve fluctuations in neurotransmitters during sleep which triggers migraines, or differences in normal morning routines disrupting usual blood sugar levels.
The reason why too little sleep can trigger an attack is easier to explain though.
In 2011, researchers from Missouri State University published a study which showed that a lack of sleep increases the creation of proteins in the body that cause chronic pain. It appears that the proteins reduce the body’s pain threshold, and can spark intense migraine headaches. Supporting the pain-sleep link, a 2015 study found that people with insomnia and other sleep issues appeared to be more susceptible to pain than people without sleep issues.
It’s also worth noting that morning migraines can be particularly bad because often you will have been asleep when the migraine began, and as the best time to take migraine medication is at the beginning of the attack before the attack takes full hold, any medications taken once you’re awake and aware of it will be less effective. Not what you want to read, but it does explain why morning migraines can be some of the most dreaded.