Herbert B. Newton, MD, FAAN

DESCRIPTION

Headache is one of the most common medical complaints of modern society, affecting virtually every person during their lifetime. Each year, more than 5% of the US population seeks medical attention for headache. More than 1% of primary care and emergency room visits are due to headache. Most recurrent headaches are symptomatic of a chronic primary headache disorder.

• Primary headaches occur without an underlying cause and include migraine, tension type, cluster, and miscellaneous headaches (such as benign exertional headache).
• Secondary headaches always have a direct underlying cause [e.g., subarachnoid hemorrhage (SAH), brain tumor, meningitis, carotid dissection, sinusitis, medications], some of which can be life-threatening.
• Headache affects all races; tension headaches and migraines may be more common in Caucasians. The peak age for headaches in adults is between 30 and 40 years. Tension headaches and migraines are more common in women than men.

EPIDEMIOLOGY

Incidence

For tension headaches, the estimated incidence for ≥15 headache days per year was 14.2 per 1,000 person-years. For migraines, the estimated incidence was 8.1 cases per 1,000 person-years.

Prevalence

For tension headaches, the estimated 1-year prevalence was 38.3%. For migraines, the estimated prevalence was 12% in the general population.

RISK FACTORS

The risk factors for headaches vary, depending on the specific type. In general, the degree of life stress and fatigue may increase the likelihood of tension headaches and migraine.

Genetics

Genetic influences are strongly suspected for migraine and cluster headaches, although the specific genes and mechanisms remain unclear.

GENERAL PREVENTION

There are no general preventive measures for headache. Specific preventive strategies regarding lifestyle, diet, sleep, etc., will be variable between headache subtypes.

PATHOPHYSIOLOGY/ETIOLOGY

The pain of headache can be caused by several different mechanisms, including elevated intracranial pressure, inflammation or irritation of pain-sensitive intracranial structures (e.g., vessels, meninges), and inflammation or damage to structures in the head and neck region (e.g., muscles). Migraine pain is incompletely understood, but involves dysfunction of brainstem control over the trigeminovascular system, with dilation and inflammation of innervated vessels and release of vasoactive neuropeptides. Cluster headaches may involve abnormal interactions between the trigeminovascular system and the posterior hypothalamic circadian cycling mechanism. Tension headache involves inflammation and tenderness of the pericranial and upper cervical musculature. Central mechanisms may also be involved, including over-sensitization to peripheral activation of muscle nociceptive afferent input.

COMMONLY ASSOCIATED CONDITIONS

This will vary depending on the specific type of headache syndrome. For example, there is a frequent association between migraine and multiple sclerosis.

[Outline]

• Information
• Description
• Epidemiology
  • Incidence
  • Prevalence
• Risk Factors
  • Genetics
• General Prevention
• Pathophysiology/Etiology
• Commonly Associated Conditions

HISTORY

• The headache history is essential to establish the proper diagnosis. Several key issues should be discussed:
  • Age of onset: Migraines usually begin before the age of 40. Temporal arteritis typically begins after age 50.
  • Time to maximum intensity: Thunderclap headaches are severe, with maximum intensity within 1 minute, and can be caused by SAH, carotid artery dissection, and migraine. Severe headaches can also have a gradual onset, such as migraine or viral meningitis.
  • Frequency: Primary headaches are quite variable in frequency, ranging from a few migraines in a lifetime to cluster headaches occurring up to 8 times daily.
  • Time of day: Cluster headaches often occur during certain times of the day and may awaken the sufferer from sleep about the same time. Headaches that awaken from sleep are usually benign (e.g., migraine, cluster). However, they can also occur with brain tumors, meningitis, and SAH. Tension type headaches often occur in the afternoon.
  • Duration: Migraine typically lasts 4–72 hours without treatment. Cluster headaches typically last 15–180 minutes. Tension type headaches typically last 30 minutes to days.
  • Triggers: Most migraineurs have one or more triggers that can induce a headache. During periods of cluster headaches, alcohol can be a trigger. Tension type headaches can be triggered by stress.
• About 60% of migraineurs have a prodrome before the headache. Complaints may involve the mental state (irritability, depression, euphoria) and neurological function (decreased concentration; light, noise, and smell hypersensitivity), as well as more general function (diarrhea or constipation, thirst, sluggish feeling, food cravings, or neck stiffness). About 20% of migraines involve an aura, which generally develops over 5–20 minutes and lasts less than 60 minutes. The headache can begin before, during, or after the aura. The most common auras in descending frequency are visual, sensory, motor, and speech and language abnormalities. Prodromal low-grade fever and upper respiratory symptoms or diarrhea are frequently present in viral meningitis.
  • Migraine is accompanied by nausea in 90% of patients, vomiting in 30%, and light/noise sensitivity in 80%. These same symptoms are often present in headaches due to SAH or meningitis. Ipsilateral conjunctival injection, tearing, and nasal congestion or drainage typically occur during cluster headaches. Ipsilateral ptosis and miosis are present in 30% of cases.
  • Cluster headaches are always unilateral while about 40–60% of migraines are unilateral. Headaches from brain tumors or subdural hematomas can be bilateral or unilateral.
  • Quality of pain is another important aspect. In about 85% of cases, migraine pain is throbbing, pounding, or pulsatile. Tension type headaches are a pressure, aching, tight, or squeezing sensation. Cluster headaches are described as boring or burning. Headaches due to brain tumors can produce a variety of pains ranging from a dull steady ache to throbbing.
  • After the headache resolves, many migraineurs report feeling tired and drained with decreased mental acuity. Depression or euphoria is sometimes reported. In some systemic disorders, high fever and headache may then be followed by other symptoms or signs.

PHYSICAL EXAM

In the vast majority of patients with primary headache disorders, the neurological examination will be intact and non-focal. Some patients with complicated migraine may have mild focal findings. In general, the presence of focal neurological deficits dramatically increases the potential for a secondary headache disorder.

DIAGNOSTIC TESTS AND INTERPRETATION

Lab

Initial Lab Tests

ESR is necessary when temporal arteritis is under consideration. A vasculitis screen (e.g., ESR, ANA, rheumatoid factor, ENA) is helpful in patients with headache and arthralgias. Endocrine and metabolic testing may be necessary to rule out other systemic disorders that can cause secondary headache.

Follow-Up & Special Considerations

Lumbar puncture, usually after CT/MRI, may be helpful to exclude SAH, infection (e.g., meningitis, encephalitis, HIV), or low or high CSF pressure.

Imaging

Initial Approach

A CT scan of the head will detect most pathology able to cause headaches and is the preferred study for acute head trauma and SAH. MRI scan of the brain (with and without gadolinium) is more sensitive than CT and is superior for the evaluation of all other causes. Magnetic resonance angiography may detect intracranial aneurysms and carotid dissection. The yield of a CT or MRI scan in a patient with headache and a normal neurological examination is about 2%.

Pathological Findings

The pathological findings in most primary headache disorders are nonspecific; in many cases the brain may be unremarkable. For secondary headache disorders, the pathology will vary depending on the underlying cause.

DIFFERENTIAL DIAGNOSIS

In addition to the common primary headache syndromes (e.g., migraine, tension, cluster), other secondary headaches to consider include: Head and neck trauma, subdural or epidural hematoma; headaches during pregnancy and the postpartum period, consider pre-eclampsia and cortical vein thrombosis; in obese young women, consider pseudotumor cerebri; pheochromocytoma should be considered in patients with paroxysmal hypertension accompanied by headache; new onset headache in an HIV-positive patient could be due to mass lesion (e.g., lymphoma) or infection (e.g., meningitis); headaches in patients with a cancer diagnosis should be screened for brain metastasis; SAH should be considered in a patient with the acute onset of the worst headache of their life; frequent use of prescription and over-the-counter drugs (including analgesics) may lead to persistent rebound headaches; oral contraceptives can cause a vascular type headache in some women; headaches associated with fever, stiff neck, nausea and vomiting, and altered sensorium may be related to CNS infection.

[Outline]

• History
• Physical Exam
• Diagnostic Tests and Interpretation
  • Lab
    • Initial Lab Tests
    • Follow-Up & Special Considerations
  • Imaging
    • Initial Approach
  • Pathological Findings
• Differential Diagnosis

MEDICATION

First Line

For abortive treatment of migraine, the triptan medications are preferred. For prophylactic treatment, choices include beta-blockers, valproate, and amitriptyline. Cluster headaches respond best to oxygen and subcutaneous sumatriptan; corticosteroids may also be of benefit.

Second Line

Other drugs to consider for migraine or cluster headaches include ergot derivatives, serotonin antagonists, calcium channel blockers, gabapentin, nonsteroidal anti-inflammatory drugs, topiramate, and SSRIs.

ADDITIONAL TREATMENT

General Measures

Will vary depending on the specific form of primary or secondary headache disorder. Non-pharmacological methods of treatment may be helpful. Migraine headaches may resolve with sleep or improve with lying down in a dark, quiet room; the application of ice to the forehead may help. Tension type headaches may improve with relaxation techniques in some patients and an exercise regimen in others.

SURGERY/OTHER PROCEDURES

Surgery is not indicated for primary headache disorders, but may be appropriate for specific secondary headache disorders (e.g., brain tumor, SAH, abscess).

IN-PATIENT CONSIDERATIONS

Admission Criteria

Admission is not indicated for most patients with primary headache disorders, except for treatment of status migrainosus. Admission is often appropriate for work-up and treatment of patients with secondary headache syndromes (e.g., SAH, brain tumor, meningitis).

[Outline]

• Medication
  • First Line
  • Second Line
• Additional Treatment
  • General Measures
• Surgery/Other Procedures
• In-Patient Considerations
  • Admission Criteria

FOLLOW-UP RECOMMENDATIONS

Patients with primary and secondary headaches will need intermittent follow-up to assess response to treatment and, in some cases, to follow neurological status.

Patient Monitoring

Will be specific to the type of primary or secondary headache disorder.

DIET

Will be specific to the type of primary or secondary headache disorder.

PATIENT EDUCATION

Patients with primary headache disorders should be thoroughly educated about the specifics of their form of headache, and instructed about behavioral and lifestyle changes that might improve control (e.g., avoidance of triggers).

PROGNOSIS

The course and prognosis for most patients with primary headache disorders is good, with adequate control of headache pain after appropriate diagnosis and treatment. For secondary headache disorders, the course and prognosis is quite variable and depends on the specific cause.

COMPLICATIONS

On occasion, patients with complicated migraines can develop focal neurological deficits.

[Outline]

• Follow-Up Recommendations
  • Patient Monitoring
• Diet
• Patient Education
• Prognosis
• Complications

• Cathcart S, Winefield AH, Lushington K, et al. Stress and tension-type headache mechanisms. Cephalalgia 2010;30:1250–1267.
• De Luca GC, Bartleson JD. When and how to investigate the patient with headache. Semin Neurol 2010;30:131–144.
• Francis GJ, Becker WJ, Pringsheim TM. Acute and preventive pharmacologic treatment of cluster headache. Neurology 2010;75:463–473.
• Robbins MS, Lipton RB. The epidemiology of primary headache disorders. Semin Neurol 2010;30:107–119.
• Taylor FR. Acute treatment of migraine headaches. Semin Neurol 2010;30:145–153.

SEE-ALSO

• Migraine
• SAH
• Brain tumor
• Meningitis
• Encephalitis

ICD9

• 346.90 Migraine, unspecified, without mention of intractable migraine without mention of status migrainosus
• 339.10 Tension type headache, unspecified
• 784.0 Headache