Primary headaches are not associated with other diseases.
Examples of primary headaches are migraine headaches, tension headaches, and cluster headaches.
Tension headaches are the most common type of primary headache.
As many as 90% of adults have tension headaches.
Tension headaches are more common among women than men.
Migraine headaches are the second most common type of primary headache.
Migraine headaches affect children as well as adults.
Before puberty, boys and girls are affected equally by migraine headaches,
After puberty more women than men have them.
Migraine often goes undiagnosed or is misdiagnosed as tension or sinus headaches.
Cluster headaches are a rare but important type of primary headache, affecting mainly men.
The average age of cluster headache sufferers is 28-30 years of age,
Secondary headaches are caused by other diseases. The associated disease may be minor or major.
Life threating conditions
Secondary headaches may result from innumerable conditions,
ranging from life-threatening ones such as brain tumors, strokes, meningitis, vasculitis, and subarachnoid hemorrhages
less serious but common conditions
withdrawal from caffeine, sinus infection (sinusitis),
discontinuation of analgesics (painkilling medication).
Pregnancy sometimes causes headaches.