CHAPTER 102
Headaches
Huma Sheikh, MD; Shivang Joshi, MD, MPH, BPharm; Elizabeth Loder, MD
Definition
The three major primary headache disorders are migraine, cluster, and tension-type headache [1]. Although all three syndromes are characterized by chronic, recurrent, and potentially disabling headaches, specific diagnosis is important because of differing natural history and treatment.
Headache disorders are classified according to criteria outlined in the International Classification of Headache Disorders, originally developed by the International Headache Society in 1988 and revised in 2004 [1]. The criteria are available online (www.ihs-headache.org) and are due to be revised soon [2]. However, changes to criteria for the three primary headache disorders are expected to be minor. Diagnosis of all but a few rare migraine subtypes remains clinical, based on the patient’s history and an examination that rules out secondary causes of headache (not covered in this chapter). The International Classification of Headache Disorders criteria were developed for research purposes and lack sensitivity when they are used in the clinical setting. Both migraine and tension-type headaches are more common in women than in men; cluster headache is generally a male disorder. Peak prevalence of migraine occurs during midlife, when it affects almost a quarter of all women and roughly 10% of men [3]. Recurrent headaches are not rare in children, but accurate diagnosis can be difficult because headache presentation in children varies from that in adults, and children may have difficulty describing the headache characteristics needed for a diagnosis to be made [4].
Migraine
Migraine is subclassified as migraine without aura (Table 102.1) and migraine with aura (Table 102.2). About 20% of patients have aura, usually preceding the headache, which consists of focal neurologic signs or symptoms that begin gradually and fade away within 30 to 60 minutes as the headache begins. The most common type of aura involves visual disturbances, typically an enlarging scotoma, but patients can also see shapes such as stars, zigzag lines, or other visual distortions, including field cuts and photopsias. Sensory or motor problems occur far less frequently. Blurry vision is usually not considered a part of aura. Migraine can also be classified as episodic or chronic (15 or more migraine headache days per month). Three gene mutations have been identified that are associated with a particular subtype of migraine with aura known as familial hemiplegic migraine. These genes influence the stability of neuronal cell membranes [5,6]. Some patients are able to identify triggers for their headache, including exertion, certain foods, and hormonal influences.
Table 102.1
Diagnostic Criteria for Migraine without Aura
A. At least five attacks fulfilling B-D.
B. Headache attacks lasting 4-72 hours (untreated or unsuccessfully treated).
C. Headache has at least two of the following characteristics:
2. Pulsating quality
3. Moderate or severe intensity (inhibits or prohibits daily activities)
4. Aggravated by or causes avoidance of routine physical activity
D. During headache at least one of the following:
2. Photophobia and phonophobia
E. At least one of the following:
2. History and/or physical and/or neurologic examinations do suggest such disorder, but it is ruled out by appropriate investigations.
3. Such disorder is present, but migraine attacks do not occur for the first time in close temporal relation to the disorder.
From Headache Classification Subcommittee of the International Headache Society. The International Classification of Headache Disorders: 2nd edition. Cephalalgia 2004;24(Suppl 1):1-160.
Table 102.2
Diagnostic Criteria for Migraine with Aura
A. At least two attacks fulfilling B.
B. At least three of the following four characteristics:
2. At least one aura symptom develops gradually over more than 4 minutes, or two or more symptoms occur in succession.
3. No aura symptom lasts more than 60 minutes. If more than one aura symptom is present, accepted duration is proportionally increased.
4. Headache follows aura with a free interval of less than 60 minutes. (It may also begin before or simultaneously with the aura.)
C. At least one of the following:
2. History and/or physical and/or neurologic examinations do suggest such disorder, but it is ruled out by appropriate investigations.
3. Such disorder is present, but migraine attacks do not occur for the first time in close temporal relation to the disorder.
From Headache Classification Subcommittee of the International Headache Society. The International Classification of Headache Disorders: 2nd edition. Cephalalgia 2004;24(Suppl 1):1-160.
Cluster
Cluster headaches are strictly unilateral headaches that are far more common in men than in women, but the prevalence in the general population overall is approximately 0.1% [7]. The pain is sharp and steady, in contrast to the throbbing pain of migraine, and localized to the orbital area. Diagnostic criteria require the presence of at least one autonomic sign or symptom during the headache, such as ipsilateral conjunctival injection, lacrimation, rhinorrhea, ptosis, or miosis.
Cluster headache is so called because the headaches occur regularly in most cases, from one to eight times a day, during a period of 2 weeks to 3 months that is referred to as a cluster episode. The headaches then completely remit for months or years. In chronic cluster headache, there are no headache-free periods or remissions, or they are less than 2 weeks in duration [8]. Patients with cluster headache usually describe alcohol intolerance during the cluster episode and generally note intense restlessness during the headache.
Tension Type
Tension-type headaches can vary in length from 30 minutes to 7 days. They are typically bilateral, moderate in intensity, and described as a pressing, squeezing sensation that is not affected by physical activity. Associated symptoms, such as nausea, vomiting, photophobia, and phonophobia, are generally not present or are mild. Tension-type headache is subclassified as infrequent episodic if it occurs less than 1 day per month, frequent episodic if it occurs from 1 day to 14 days per month, and chronic with attacks occurring 15 days or more per month for at least 6 months [1]. Patients with tension-type headache typically do not spontaneously report symptoms other than headache. A diagnosis of migraine should be reexamined if multiple associated symptoms are reported, like nausea and photophobia, which are thought to be a part of the sympathetic activation that occurs with migraines.
