Description

• Primary headache: headache without an identifiable underlying etiology; includes but not limited to migraine, tension headache, cluster headache, and other trigeminal autonomic cephalgias; may be episodic or chronic in nature
• Secondary headache: headache attributed to an identifiable underlying etiology
• Other: unusual headaches, especially in children, that include various cranial neuralgias and central and primary facial pain

Epidemiology

• Headache prevalence can approach 30–50% by school age, 60–80% by early adolescence, and as high as 85–90% by adulthood.
• Tension-type headache is most common type of headache, with migraine second.
• Mean age of onset for migraine is 7 years for boys and 11 years for girls. Migraine precursors such as abdominal migraine, cyclic vomiting syndrome, and benign paroxysmal vertigo of childhood can be seen even younger. These may transform into migraines by puberty.
• Overall migraine reported prevalence ranges between 8% and 23%. Suspicion is that migraine prevalence may be as high as 30–35% due to underreporting. Prevalence of chronic daily headache in younger children is 2–4% and 4–5% in adolescence/adulthood.
• Until puberty, migraines more common in males (55–60%), postpuberty in females (75%)

Risk Factors

Ethnicity plays a role, with majority of reported chronic migraine sufferers being Caucasian.