Diagnosis:

Diagnosing the cause of persistent daily headache is difficult, even for expert doctors. Studies report that people who visit the emergency room with disabling headache are often misdiagnosed as tension-type headaches instead of migraines. It is important to choose a doctor who is sensitive to the needs of headache sufferers and aware of the latest advances in treatment.

Extensive testing may be advised for anyone with a chronic, daily headache. Tracking times of medications, withdrawal, and headache, using the headache diary, is usually very helpful in diagnosis.

According to the International Headache Society, a diagnosis of tension-type headache is suggested by the following symptoms:

• Pressing or tightening (but non-pulsating) feeling
• Mild-to-moderate pain on both sides of the head
• Not aggravated by routine physical activity (walking, climbing stairs, etc.)

In episodic tension-type headaches:

• No nausea or vomiting
• Photophobia (intolerance of light) or phonophobia (intolerance of sound) may be absent or one of these symptoms (but not both) may be present

In chronic tension-type headaches:

• No vomiting
• No moderate or severe nausea
• No more than one of the following symptoms: Mild nausea, photophobia, or phonophobia
• Some types of chronic tension headache may include tenderness upon manual palpitation of the head (pericranial tenderness).

Differentiating Medication-Overuse (Rebound) Headache from Tension-Type Headache.

About a third of persistent headaches are the result of the rebound effect caused by the overuse of headache medications (formerly called rebound headaches).

Usually in such cases, medications have been taken on an ongoing basis for more than 3 days each week. If patients stop taking these drugs, the headaches come back. The patient then starts taking the drugs again. Eventually the headache simply persists and medications are no longer effective. Even after successful medication withdrawal, relapse is common, particularly with drugs that contain caffeine, so doctors should check for this type of headache even in patients who have previously been treated.

Medications implicated in medication-overuse headache include barbiturates, sedatives, narcotics, and migraine medications, particularly those that also contain caffeine. (Heavy caffeine use can also cause this condition.) Simple painkillers, such as aspirin or ibuprofen, are less likely causes of medication-overuse headaches.

Differentiating Tension Headaches from Chronic Migraines

Migraines and tension headaches have some similar characteristics, but also some important differences:

• Migraine pain is usually throbbing, while tension-type headache pain is usually a steady ache
• Migraine pain may affect only one side of the head, while tension-type headache pain typically affects both sides of the head
• Migraine pain, but not tension-type pain, worsens with head movement
• Migraine headaches, but not tension-type headaches, may be accompanied by nausea or vomiting, sensitivity to light and sound, or aura

[For more information, see In-Depth Report #97: Migraine headaches.]

Medical and Personal History

For an accurate diagnosis, the patient should describe the following:

• Duration and frequency of headaches
• Recent changes in their character
• Location of the pain
• Type of pain (throbbing or steady pressure)
• Intensity of the headache
• Associated symptoms, such as visual disturbances or nausea and vomiting. (These are seen most often with migraines.)
• Behaviors during a headache. Different behaviors may help distinguish between migraine and tension headaches. People with tension headaches tend to relieve pain by massaging the scalp, temples, or the nape of the neck. People with migraines are more likely to compress the forehead and temples (tying a scarf around the head) or to apply cold to the area. They also tend to isolate themselves, lie down, induce vomiting, and use more pillows than usual. (None of these maneuvers do much good in relieving either headache, unfortunately.)

The patient should also report any other conditions that might be associated with headache, such as any:

• Chronic or recent illness and their treatments
• Injuries, particularly head or back injuries
• Dietary changes
• Current medications or recent withdrawal from any drugs, including over-the-counter or natural remedies
• History of caffeine, alcohol, or drug abuse
• Serious stress, depression, and anxiety

The doctor will also need the patient's general medical and family history, particularly concerning headaches or other neurological diseases.

Headache Diary to Identify Triggers

The patient should try to recall what seems to bring on the headache and anything that relieves it. Keeping a headache diary is a useful way to identify triggers that bring on headaches, and to help the doctor differentiate between migraine and tension-type headache. Be sure to include all events preceding an attack. Often two or more triggers interact to produce a headache.

Researchers are investigating triggers of headaches to determine if certain ones are more likely to set off different primary headaches. In general, however, the same stimuli seem to trigger any of the primary headaches, although people with migraines may be more sensitive to some of them (weather, certain smells, light, and smoke) than people with tension headaches.

Tracking medications is an important way of identifying medication-overuse headache or transformed migraine.

Be sure to attempt to define the intensity of the headache. There are different scoring symptoms available that help communicate the severity of the pain to the doctor. For instance, the following is a number system that can be helpful:

1 = Mild, barely noticeable

2 = Noticeable, but does not interfere with work/activities

3 = Distracts from work/activities

4 = Makes work/activities very difficult

5 = Incapacitating

Physical Examination

In order to diagnose a chronic headache, the doctor will examine the head and neck to check for muscle tenderness. The doctor may also perform a neurologic examination, which includes a series of simple exercises to test strength, reflexes, coordination, sensation, and mental function. The doctor may also recommend an eye examination.

Imaging Tests

Imaging tests of the brain may be recommended under the following circumstances:

• If the results of the history and physical examination suggest neurologic problems
• Changes in vision,
• Muscle weakness.
• Fever
• Stiff neck
• Changes in the way someone walks
• Changes in mental status including signs of disorientation

Imaging tests may also be recommended for:

• Patients with headache that wakes them at night.
• A sudden or severe headache, or a headache that is the worst headache of someone's life
• For patients with history of cancer or weakened immune system
• For new headaches in adults over 50 years, especially in the elderly. In this age group, it is particularly important to first rule out age-related disorders, including stroke, low blood sugar (hypoglycemia), fluid accumulation in the brain (hydrocephalus), and head injuries (usually from falls).
• For patients with worsening headache or headaches that do not respond to routine treatment

The following tests may be used:

• A CT (computed tomography) scan may be ordered to rule out other conditions, particularly chronic sinusitis, which, in one study, occurred in 20% of patients with chronic headache. Other findings include aneurysms, benign or cancerous growths, and other abnormalities in the brain.
• X-rays and other tests may also be used if sinusitis is strongly suspected.
• A neck x-ray can reveal arthritis or spinal problems.
• Other tests include an MRI (magnetic resonance imaging), EEG (electroencephalogram), lumbar puncture, ultrasound testing, and cerebral angiography, which are only performed if there is reason to suspect an underlying disease.

Headache Symptoms that Could Indicate Serious Underlying Disorders

Headaches indicating a serious underlying problem, such as cerebrovascular disorder or malignant hypertension, are uncommon. (It should again be emphasized that a headache is not a common symptom of a brain tumor.) People with existing chronic headaches, however, might miss a more serious condition believing it to be one of their usual headaches. Such patients should immediately call a doctor if the quality of a headache or accompanying symptoms has changed. Everyone should call a doctor for any of the following symptoms:

• Sudden, severe headache that persists or increases in intensity over the following hours, sometimes accompanied by nausea, vomiting, or altered mental states (possible hemorrhagic stroke).
• Sudden, very severe headache, worse than any headache ever experienced (possible indication of hemorrhage or a ruptured aneurysm).
• Chronic or severe headaches that begin after age 50.
• Headaches in the back of the head accompanied by other symptoms, such as memory loss, confusion, loss of balance, changes in speech or vision, or loss of strength in or numbness or tingling in arms or legs (possibility of small stroke in the base of the skull).
• Headaches after head injury, especially if drowsiness or nausea are present (possibility of hemorrhage).
• Headaches accompanied by fever, stiff neck, nausea, and vomiting (possibility of spinal meningitis).
• Headaches that increase with coughing or straining (possibility of brain swelling).
• A throbbing pain around or behind the eyes or in the forehead accompanied by redness in the eye and perceptions of halos or rings around lights (possibility of acute glaucoma).
• A one-sided headache in the temple in elderly people; the artery in the temple is firm and knotty and has no pulse; scalp is tender (possibility of temporal arteritis, which can cause blindness or even stroke if not treated).
• Sudden onset and then persistent, throbbing pain around the eye possibly spreading to the ear or neck unrelieved by pain medication (possibility of blood clot in one of the sinus veins of the brain).