CLINICAL REVIEW: Headaches Part 2 – Secondary Headache
The essentials
* Sinister headaches may be life threatening, but screening is possible.
* Sinister headaches should be referred for specialist management.
* Migraine may double the risk of stroke.
* Purulent nasal discharge and a febrile illness indicate sinus headache.
* Facial pain syndromes are chronic disabling conditions of older people.
1. The diagnosis of sinister headaches
GPs worry about whether a patient’s headache symptoms indicate a serious underlying pathology. Patients, too, may be worried that a brain tumour or other life-threatening disorder is causing their headache. However, the physician should realise that most headache sufferers who seek advice have common, benign headaches such as migraine or chronic daily headache. Several illnesses produce headaches as part of their symptom complexes, but in most cases these are relatively minor conditions.
Sinister headaches
Sinister headaches arise as a side-effect of serious and life- threatening illnesses, and are rarely seen in primary care. A recent UK survey of a population of 7,000 patients over a 10-year period identified only 19 cases of serious cranial pathology associated with headache – an incidence of only 0.03 per cent.
Serious illnesses that produce such headaches include meningitis and other infections, subarachnoid haemorrhages following head injury, pre-existing aneurysms or vascular malformations, and cranial arteritis due to inflammation of the cranial arteries.
Other serious pathologies that can cause headaches are primary brain tumours, cerebral metastases, cerebral abscesses caused by bacterial, fungal or parasitic infections, and strokes and transient ischaemic attacks.
Recognising sinister headaches
GPs need to be able to recognise sinister headaches so they can refer the patient to an appropriate specialist or arrange immediate hospital admission. The Headache Care for Practising Clinicians organisation has developed an algorithm to help GPs diagnose sinister headaches, incorporating the patient’s age, headache onset and acuteness and presenting symptoms (see above).
Suspect a headache as being sinister if the patient is very young (under five years) or relatively elderly (over 50 years). Also suspect a sinister cause if the headache is new in onset and/or different from other headaches previously experienced, is acute, or is described as the worst ever.
Other causes for concern are if the headache is associated with a range of other symptoms such as a rash, a non-resolving neurological deficit, vomiting, pain or tenderness, accident or head injury, an infection or hypertension.
Consider a sinister cause if any neurological change or deficit does not disappear when the patient is pain-free between headache attacks. Also, atypical or non-reproducible (isolated) symptoms may be present, and a neurological examination may show abnormal results.
2. Epidemiology, symptoms and management
Cranial arteritis
Cranial arteritis (temporal arteritis, giant cell arteritis) affects people over 50 years of age, is more common in women than men and typically affects Caucasians aged over 60 and African Caribbeans over 50.
Cranial arteritis involves inflammation of the arteries of the head. The arteries become thickened, stop pulsating, are tender to the touch and the skin over the artery becomes red. It is often associated with general malaise and a bilateral or unilateral continuous headache, and is exacerbated by hair brushing over the affected arteries. Pain in the muscles of the jaw may also occur when chewing (jaw claudication).
Meningitis
Viral meningitis is usually mild, but the bacterial form due to Haemophilus influenzae or Meningococcus types B and C is life threatening.
The headache of bacterial meningitis is typically an acute headache in children accompanied by a rash that does not fade with pressure, a stiff neck, dislike of bright lights, fever and vomiting. There is drowsiness, impaired consciousness and eventual coma.
Subarachnoid haemorrhage
Subarachnoid haemorrhage occurs when a blood vessel ruptures into the cerebrospinal fluid, either spontaneously or after injury or unaccustomed exercise. It is most prevalent in people aged 35-60.
Typically, a new-onset acute headache occurs with associated nausea and vomiting, photophobia, drowsiness and neck stiffness. Unconsciousness may occur. Diagnosis usually involves CT scanning and angiography.
Hypertension
Only extremely high blood pressure may be associated with headache and this may be relieved if the blood pressure is reduced.
The pain is pulsating or throbbing, present on waking and rare in young people.
Underlying causes for an acute increase in blood pressure such as phaeochromocytoma and pre-eclampsia should be sought and treated.
Cerebral tumours and abscesses
Headache is usually present in primary brain tumours with symptoms or signs of neurological deficit between attacks. A history of less than six months with neurological deficit may indicate a brain tumour and should be investigated.
Cerebral metastases may present as headaches in patients with a history of malignancy with neurological signs and/or deficit. Cerebral abscesses present as acute headache with neurological deficit, fever and other signs of infection. Specialised imaging procedures may be needed for diagnosis.
The management of patients suspected of having sinister headaches requires thorough evaluation, and usually means referral to a hospital or to a specialist.
3. Facial pain syndromes
Trigeminal neuralgia
Trigeminal neuralgia is the most common neurological syndrome in the elderly, with an incidence of about 155 per million, and is three times more common in women than in men. It is an acute, short- lived, severe, paroxysmal pain of the facial or frontal regions along the divisions of the trigeminal nerve, but can also present as a sustained, deep, dull ache.
Characteristic features predicting diagnosis of trigeminal neuralgia include spasms of unilateral, sudden, intensely severe, sharp, superficial, stabbing or burning pain along the trigeminal nerve. This may be associated with some twitching of the facial muscles.
The pain lasts for a few seconds up to two minutes. Attacks are often provoked by such simple activities such as washing, shaving, talking or brushing teeth. The patient is symptom-free between attacks.
When the diagnosis is confirmed, carbamazepine is the most commonly used first-line treatment. If this or alternative drugs do not control the symptoms, referral for consideration of surgery may be appropriate.
Post-herpetic neuralgia
Post-herpetic neuralgia follows an eruption of herpes zoster, is most common in the elderly, and can persist for months or years. It is associated with depression and dependency problems, and is extremely disabling for patients.
The pain often starts during the acute rash phase, and particularly causes problems when it persists afterwards.
The diagnosis is usually straightforward after an eruption of herpes zoster, but sometimes there is difficulty if the rash is mild, hidden or absent, or undetectable such as in the ear. Symptoms include a constant, deep, unilateral pain with repetitive stabs or needle-prick sensations, and light touch can trigger the symptoms and lead to itching.
Treatment depends on the stage of the infection. Antiviral drugs, analgesics and topical applications can help in the acute phase of the rash, and tricyclic antidepressants and local application of capsaicin can be used for pain that persists after the rash has cleared.
Temporomandibular joint dysfunction
Temporomandibular joint dysfunction mostly affects older people, with pain in the upper part of the head on the affected side, limited jaw movement, muscle tenderness and joint crepitus.
The cause is probably muscle spasms in the j aw. Episodes of jaw clenching may lead to tension-type headaches, while teeth grinding when asleep can lead to migraine attacks on wakening.
The diagnosis can be made by finding crepitus in the joint on jaw movement, limited or jerky movements,pain and locking of the jaw on opening. Clenching and/or gnashing of teeth (especially teeth grinding while asleep), and biting of the tongue, lips or cheek can occur.
Following diagnosis, it is usually best for a GP to refer the patient to a dentist. The GP can provide additional stress management programmes and prophylaxis with a tricyclic antidepressant if necessary.
4. Managing sinus headache
Infections of the cranial sinuses may cause headaches in all age groups, particularly acute sinusitis, where the infection can last from one day to three weeks.
Symptoms include headache and/or facial pain over the sinuses together with an acute febrile illness and apuraient nasal discharge.The site of the pain varies according to the location of the infection.
Maxillary sinusitis pain is felt mostly in the cheek, gums, teeth and upper jaw, while ethmoid sinusitis pain is between the eyes, with eye tenderness aggravated by eye movement. Frontal sinusitis causes pain in the forehead, and sphenoidal sinusitis pain is often at the vertex of the skull. The patient also usually complains of pain in or behind the eyes.
Sinus headaches usually have a dull, aching quality that is worsened by sudden movements or by bendin\g over. Pansinusitis is a more severe form of infection where the pain is more generalised. This is a potentially serious condition and, if it is suspected, one that requires urgent specialist intervention.
Diagnosis
The main points to look for in confirming a diagnosis of acute sinusitis are a purulent nasal discharge, evidence of acute febrile illness, and headache in the sinus areas occurring simultaneously with the sinusitis. The pain is a dull and aching headache, and is exacerbated by bending down. Most patients usually complain of a diminished sense of smell.
Acute sinusitis is a relatively uncommon cause of headache, and is greatly over-diagnosed due to confusion with migraine and tension- type headache. It is important to make a positive diagnosis of sinusitis rather than a diagnosis by exclusion. Apart from the features already described, imaging or flexible endoscopy may be needed to confirm the diagnosis. In the absence of this evidence, migraine may be a more likely diagnosis. Also, in migraine the sense of smell is usually heightened, whereas in sinus headaches it is diminished.
Management
Once the diagnosis is confirmed, broad-spectrum antibiotics can be prescribed, and local treatment with steam inhalations or vasoconstrictor agents can be recommended. Oral decongestants can be given if treatment is required for more than 72 hours. If these measures fail, it is probably best to refer the patient to a specialist.
5. Migraine and stroke associations
The link between migraine and stroke has been reported for many years, although the true associations between the two are only now becoming clear. The risk factors identified for stroke that include oral contraceptives, migraine, smoking, and hypertension are additive in their effect, as shown in the graph (right). The risk is much higher in patients who have migraine with an aura.
Studies have shown that the risk of ischaemic stroke is higher in women under the age of 45, particularly for smokers and those currently using oral contraceptives. It is especially important to advise young women with migraine that they should not smoke. If migraine sufferers insist on using the Pill, they should use the lowest dose of oestrogen possible.
A recent systematic review suggests that migraine doubles the risk of stroke and that migraine sufferers on the Pill are eight times more likely to have a stroke than those who are not.
Migrainous infarction
True migraine-induced stroke is known as migrainous infarction, and is rare. It constitutes only 0.5-1.5 per cent of all new cerebral infarctions, and less than one-third of migraine-related strokes. In most cases the link between the migraine and the stroke is coincidental. Headache is a common feature of stroke and may be mistaken for a migraine attack.
Possible aetiological factors
Recent research has cast light on the possible aetiology of migraine-related strokes. There are epidemiological and genetic studies to show that migraine with aura is associated with a patent foramen ovale (PFO), a relatively common cardiac defect. Failure of the foramen ovale to close during fetal development allows the right- to-left shunting of blood through the atria.
PFOs are also associated with stroke, and studies have shown that the presence of all three conditions may be significant. It may be that, in the presence of a PFO, venous thrombi are able to transfer from the venous to the arterial circulation without being filtered by the lungs, resulting in strokes when emboli reach the cerebral circulation.
This simple algorithm can help GPs determine if a headache is sinister in origin or can be considered benign
Key points
* Most headache sufferers who consult a GP have common, benign headaches.
* The average GP will see less than one patient with sinister headaches per year.
* Sinister headaches may arise as a result of infections, tumours, and cardiovascular or cerebrovascular diseases.
* A simple algorithm can be used to screen for sinister headaches.
Subarachnoid haemorrhage causes new-onset pain
Key points
* Sinister headaches are mostly seen in older people, except for meningitis.
* Sinister headaches have characteristic symptoms that can aid diagnosis.
* Scanning procedures are frequently necessary for diagnosis.
* Management of sinister headaches is usually conducted in referral centres.
Herpes zoster can result in post-herpetic neuralgia
Key points
* Facial pain syndromes include trigeminal and post-herpetic neuralgia, and temporomandibular joint problems.
* These conditions mostly affect older people.
* Facial pain syndromes are chronic disabling conditions.
* Presenting symptoms and associated management strategies vary.
Special imaging may be needed to confirm sinusitis
Key points
* Sinus infection can last from one day to three weeks.
* Acute sinusitis may cause a dull, aching headache exacerbated by movement.
* So-called sinus headaches are often due to migraine.
* True sinusitis headaches are usually treated with broad- spectrum antibiotics.
* If symptoms persist despite treatment, refer.
Risk factors for stroke are cumulative
Key points
* Migraine with aura is directly related to the risk of ischaemic stroke, particularly in young women.
* Stroke risk is doubled in migraine sufferers.
* Migraine and stroke may be associated with a co-existing patent foramen ovale.
Copyright Haymarket Business Publications Ltd. Dec 17, 2004