Headaches are one of the most medical disorders seen. It is estimated that up to 80% of the population will suffer from a tension headache in their lifetime and about 12% of the population suffer from recurrent migraines. That is a lot of people.
If you watch the ads on TV, pain medications are advertised heavily.
But what causes tension headaches?
I used to be thought that muscle tension and muscles spasms were the cause.
According to the Mayo Clinic website, the most common theory supports a heightened sensitivity to pain in people who have tension-type headaches. Increased muscle tenderness, a common symptom of tension-type headaches, may result from a sensitized pain system.
Sleep-related bruxism is known to sensitize the pain system and shares the same genetic mutation on chromosome 13 (HTR2a polymorphism). Both tension headaches and sleep-related bruxism hypersensitize the body to serotonin, a powerful neurotransmitter due to this mutation.
Tension headaches are extremely common with sleep-related bruxism patients. Waking with a tension-type headache strongly suggests the presence of sleep-related bruxism.
Both sleep-related bruxism and tension headaches affect the masseter inhibitory reflex, suppressing it. This allows the jaw muscles to contract with 100% of their bite force unchecked. This results in sensitization of the pain syndrome and the onset of tension-type headaches.
Migraine headaches differ from tension in that many people experience an aura (visual disturbances, nausea, and vomiting). Many migraine sufferers however do not have these auras, and it is this group that is associated with sleep-related bruxism.
Migraines do not share the HTR2a mutation of sleep-related bruxism and tension headaches but do suppress the temporalis inhibitory reflex, which is similar to the masseter inhibitory reflex. The result is the temporalis muscle becomes hype-active and contracts with 100% of its force. This can lead to hyper-sensitization of the pain system similar to the other two resulting in frequent migraines.