Upon completion of the chapter, the reader will be able to:
Differentiate types of headache syndromes based on clinical features.
Recommend nonpharmacologic measures for headache treatment and prevention.
Determine when the pharmacologic treatment of headache is indicated.
Construct individualized treatment regimens for the acute and chronic management of headache syndromes.
Monitor headache treatment to ensure its safety, tolerability, and efficacy.
Headache is a common medical complaint with approximately 50% of the adult population experiencing at least one headache per year.1 Even when persistent or recurrent, headaches are usually a benign primary condition; secondary headaches are caused by an underlying medical disorder and may be medical emergencies. Primary headache syndromes are the focus of this chapter. Patients may seek headache care from multiple providers. All clinicians should be familiar with the various types of headache, clinical indicators suggesting the need for urgent medical attention or specialist referral, and nonpharmacologic and pharmacologic options for treatment. The International Headache Society (IHS) classifies primary headaches as migraine, tension-type, or cluster and other trigeminal autonomic cephalalgias.2
EPIDEMIOLOGY OF HEADACHE DISORDERS
Migraine is a primary headache disorder with an estimated 3-month prevalence rate in the United States of 14.2% in adults over 18. Prevalence is higher in females at 19.1% compared to 9%. Highest prevalence was in females 18 to 44 years of age at 23.5%.3 In pediatric patients, there is also a higher incidence in females after the age of 10.4 The difference in gender distribution is thought to be due to hormonal differences.
Tension-Type Headache (TTH) is the most common primary headache disorder and can be further divided into episodic or chronic.2 The term TTH is used to describe all headache syndromes in which sensitization to pericranial nociception, noxious stimuli, is the most significant factor in the pathogenesis of pain.5 Overall reported prevalence of TTH is approximately 86%, and incidence is more common in women than men. Episodic TTH is the most common type followed by frequent episodic TTH, and chronic TTH. Incidence of TTH increases until approximately age 40, then incidence begins to slowly decline.6 Environmental factors, as opposed to genetic predisposition, play a central role in the development of TTH. The mean frequency of attacks is 3 days per month in episodic disorders; chronic TTH is defined as 15 or more attacks in a 1-month period.2
Cluster Headache and Other Trigeminal Autonomic Cephalalgias
Cluster headache disorders are uncommon and severe primary headache syndromes.2 The lifetime prevalence is estimated to be 124 per 100,000.7 Unlike migraine and TTH, cluster headaches are more frequently found in men. Onset most commonly occurs between 20 and 40 years.2 A genetic predisposition is apparent, although affected ...