Download A Method To Simplify The Diagnosis Of Headache

Number 1
A Method To Simplify The Diagnosis Of Headache
Based on Three Simple Questions
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The proper evaluation of the patient with headache includes a careful history and
thorough physical examination, the latter emphasizing the neurological
examination. After completing these steps, the busy practitioner might then think
of multiple possible diagnoses, often in a haphazard order. In order to formulate
a more rational differential diagnosis, the answers to three questions are
required.
1) How long has the patient been having headaches?
2) How often do the headaches occur?
3) How long does each individual headache last?
Using the answers to these questions, headaches can be divided into the
following five groups, each of which contains a list of the most likely causes in
that group. The causes are listed in order of their approximate frequency of
occurrence in the population as a whole – not in frequency of patients seeking
care.
Group I Headaches With Explosive Onset
1)
2)
3)
4)
Acute post-traumatic headache
Thunderclap headache
Subarachnoid hemorrhage
Stroke
Acute trauma to the head or neck is frequently followed by headache. Most often
the patient recognizes the cause and may or may not seek medical care. Acute
post-traumatic headaches start within one week following the injury and cease by
the twelfth week. If they continue longer than twelve weeks, the diagnosis is
chronic post-traumatic headache (see group V below). The other conditions on
this list are true medical emergencies and require neuroimaging studies and
often a lumbar puncture.
Group II
1)
2)
3)
4)
Recent Onset Headaches with Progressive Course
Rhinitis/ sinusitis – allergic or bacterial
Systemic infectious illness
Meningoencephalitis –viral, bacterial, spirochetal, fungal, tubercular
Adverse event from a medication
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5)
6)
7)
8)
9)
Abnormal intracranial pressure
Headache caused by caffeine withdrawal
Cervicogenic headache
Hypothyroidism
Hypertension – (if systolic >190 or diastolic >120)
This group includes headaches beginning hours, days or even weeks earlier.
Most are major medical conditions requiring specific therapy. The history and
examination usually reveal other symptoms and/ or signs that point to the
diagnosis. If proper therapy is administered, many of the conditions in this group
can be corrected.
Allergic rhinitis/ sinusitis is accompanied by pressure over the sinuses, nasal
congestion and discharge that is often non-purulent. There may be a history of
similar attacks in previous years. A careful history may reveal additional
symptoms which point to the diagnosis of migraine. Both conditions might
respond to simple analgesics. This is in contrast to the purulent drainage, fever
and often unilateral frontal headache with bacterial sinusitis, a condition that is
less frequent.
The headaches with systemic infections may start before the patient develops
significant fever, cough or other symptoms. Headache may be the only symptom
of meningoencephalitis and neck stiffness may be absent or minimal.
Occasionally cryptococcal meningitis might be present for several months before
cells and protein elevation appear in the spinal fluid.
The Physicians Desk Reference mentions headache as an adverse event of
almost every medication. The onset of headache may occur weeks or even
months after a daily medication is started. When confronted with a patient
having headache, the physician should stop every medication that is not
essential. If the patient is on an essential medication, it should be changed to
another medication having the same action. An example would be to change a
beta-blocker being given for hypertension to a calcium channel blocker.
Headaches presenting as an adverse event from medications generally clear
rapidly if the offending medication is discontinued.
There are various causes of altered intracranial fluid pressure. Benign
intracranial hypertension (also called idiopathic intracranial hypertension and
pseudotumor cerebri) is not uncommon. The patient is often female, obese and
may have various visual abnormalities. Only 8% of adult brain tumors present
with headache in the absence of seizures or other abnormal neurological
symptoms and signs. Low spinal fluid pressure typically presents with postural
headache, neck pain and dizziness. The headache worsens as the patient
stands and improves after lying down. With low CSF pressure a contrast MRI
may shows marked meningeal enhancement.
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Caffeine withdrawal headaches occur on those days when the person does not
consume their daily caffeine which is usually taken with breakfast.
Patients often have neck problems that are not the cause of their headaches.
For example they might have chronic arthritic problems in the neck but infrequent
headache. The physician must always ask which started first and inquire about
the temporal relationship of the headaches and neck conditions. The diagnosis
of cervicogenic headache is often made in error.
Hypothyroidism is usually diagnosed from the other symptoms typical for that
condition.
Mild elevations of blood pressure are usually asymptomatic. The classic British
study showed that hypertension rarely caused headache at levels below 190
systolic and 120 diastolic.
Group III Recurrent Headaches with Irregular Frequency
1)
2)
3)
4)
5)
Ice cream headache
Episodic tension-type headache
Episodic Migraine
Benign idiopathic stabbing headache
Stimulus induced headaches
positional, exertional, cough, coital
Although ice cream headaches occur almost universally, the patients with this
condition almost never seek medical attention. Most patients with infrequent or
episodic tension-type headaches obtain relief with simple OTS (off the shelf)
medications and never seek medical attention. Chronic tension-type headache
(occurring >15 days/ month) is included in group V below. From this list, the
patient with migraine is the most likely to seek medical attention. Primary,
essential or episodic migraine occurs in patients who are headache-free on most
days of the month. This is in contrast to the person having frequent migraine
(greater than 15 days per month) or some days with migraine and a dull, tensiontype headache on most of the other days. The latter two conditions are having
chronic daily headache (see group V below).
Group IV Recurrent Daily or Almost Daily Paroxysmal Headaches
(Lasting Less Than 4 Hours)
1)
2)
3)
4)
Cluster headache
Paroxysmal hemicrania
Headache due to sleep apnea
Hypnic headache
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The main features distinguishing cluster headache from paroxysmal hemicrania
is the severity, frequency and duration of each headache. Cluster headaches
are excruciating, rarely occur more than four times a day and the pain lasts for
30-180 minutes. The headaches of paroxysmal hemicrania are less intense,
may occur as often as eight times a day and the individual headaches last less
than 30 minutes. Headaches due to sleep apnea are noted upon awakening in
the mornings and usually resolve within 30 minutes. Hypnic headache usually
occur in the elderly and are only nocturnal, often awakening the patient at the
same time each night. .
Group V Recurrent Daily or Almost Daily Continuous or Almost Continuous
Headache (Lasting longer than 4 hours)
1) Rebound headache (medication overuse headache)
2) Adverse event from medications
3) Chronic post-traumatic headache
(most often a form of rebound headache)
4) Depression
5) Chronic tension-type headache (rarely is a presentation of rebound)
6) Hemicrania continua (can be a presentation of rebound)
This last group of headaches includes the patients causing the most diagnostic
and therapeutic difficulty for the physician. These patients repeatedly seek
medical care, additional imaging studies and additional medications to terminate
or prevent their headaches. In the medical literature and in the latest
classification of headaches by the International Headache Society (IHS), there
has been an unfortunate lack of uniformity in defining the conditions listed in this
table of chronic daily headaches (CDH). Some authors have advocated separate
diagnoses for daily headaches with gradual onset and a history of prior migraine
(transformed migraine), new onset with or without medication overuse, only
unilateral pain, etc. The terms used in this list have been chosen because they
are simple to comprehend and are in widespread use.
The majority of these patients with CDH are experiencing rebound headache – a
term that emphasizes that the medications taken for today’s headache rebound
and are causing tomorrow’s headache. The IHS classification designates these
as medication overuse headaches. Often the patient had started the pain
medication for some other condition such as postoperative pain, trauma, fever or
joint problems. Rebound headaches can result from the overuse of any acute
pain medication, even the triptans. These daily headaches might have started
when the patient was using daily or almost daily pain medications, but continue
to be daily or almost daily after the patient changes to another pain medication or
reduces their medications to only one or two days a week. After these patients
stop all pain relief medications, their recovery is slow – at times requiring 6+
months to reach the goal of once a week or less frequent headache. Studies
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have shown that over 75% of the patients who follow the advice to completely
stop the pain medications can reach that goal.
Daily headache as an adverse event from a medication can continue for months
or even years if the offending medication is not stopped. The condition was
discussed earlier under group II.
Acute post-traumatic headaches are common but last less than twelve weeks.
Chronic post-traumatic headaches are rebound headaches until proven
otherwise.
Symptoms of depression are frequent in patients with rebound headache, but
usually begin after the headaches have started. A patient with pre-existing
chronic depression might note an increase in the severity of their depression if
they later develop rebound headache. Infrequently a patient might present with a
short history of depression – three months or so – followed by daily tension-type
headache. In the latter patient both problems might respond to a low dose of a
simple tricyclic antidepressant.
Daily or almost daily tension-type headache without any migraine component is
an unusual presentation of rebound headache and infrequently responds to
analgesic termination. Many chronic tension-type headaches fail to improve with
any pharmacological approach.
Chronic hemicrania continua, especially if the unilateral headaches are a
combination of unilateral tension-type and unilateral migraine, is rebound until
proven otherwise. The patient should stop all analgesics. If the patient is having
mild to moderate constant, unilateral, steady pain that is associated with
autonomic findings and intermittent exacerbations, they are probably having true
hemicrania continua and should initially be treated with Indomethacin.
Revised
February 6,2012
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