Headache is one of the most common pain syndromes for which patients consult physicians. Surveys indicate that in any given year, more than 90% of American adults will have some kind of headache or head pain.1 A wide variety of conditions can present with headache. The first step in treating a patient with a primary complaint of headache is to determine whether there is a primary or a secondary headache disorder. Then it is important to make a specific, accurate diagnosis. Secondary headache disorders have an underlying cause, which can usually be determined, such as infection, eye or jaw dysfunction, tumor, aneurysm, dissection or other vascular problems, meningitis, and trauma. Fortunately, very few headaches are caused by serious organic conditions, and most of them are actually primary headache disorders, idiopathic conditions that are benign and tend to recur. The great majority of patients that present to a physician with bad headaches are diagnosed with migraine. The pathophysiology of primary headache disorders is complex and probably involves, among other things, the activation of the trigeminovascular system, meningeal inflammation, and involvement of the cortex, brainstem, and thalamus (see Chapter 29 for a discussion on the pathophysiology of headaches). Chapter 28 presents the historical features in primary headache syndromes and describes the diagnostic criteria for the three most common primary headache disorders, which are migraine, tension-type headache (TTH), and cluster headache. This chapter discusses the differential diagnosis, diagnostic testing, and management of patients with these common primary headache disorders.
Migraine is a chronic neurologic disorder with episodic manifestations. The two most common patterns of migraine are migraine without aura and migraine with aura, formerly called common migraine and classic migraine, respectively. Migraine prevalence in the United States has remained stable, reported to be 12% in the general population. There is a female predominance; migraine affects approximately 18% of women compared with 6% of men.2 Migraine can be extremely disabling, with more than 50% of individuals with migraine reporting severe impairment or the need for bed rest during a migraine attack compared with only 7.2% reporting no attack-related disability.3
A migraine attack is best looked at as being divided into four phases: the prodrome, the aura, the headache phase, and the postdrome. All four phases are not always present, and no single phase is necessary in order to diagnose migraine in a specific patient.4,5
The first phase, or prodrome, consists of various combinations of psychological, neurologic, autonomic, and constitutional symptoms that precede the headache phase of the migraine attack by several hours or even days. The reported prevalence of this phase has been variable, but more than 80% of patients have reported at least one prodromal symptom.6 Symptoms may include altered mood, irritability, depression or euphoria, fatigue, yawning, excessive sleepiness, food cravings, dizziness, pale face, stiff neck, photophobia, phonophobia, ...