A severe headache, typically lasting from four to 72 hours, accompanied by light and noise sensitivity and/or nausea and vomiting. Migraine attacks are due to spasm, followed by excessive dilation, of blood vessels in the brain.

Causes

There is no single cause of migraine, although it tends to run in families. Stress-related, food-related, or sensory-related factors (such as eating cheese or chocolate, or drinking red wine) may trigger attacks. In women, menstruation, oral contraceptives, and HRT may also be triggers.

Types and symptoms 

There are two types: migraine with aura (an impression of flashing lights and/or other neurological symptoms such as numbness and tingling) and migraine without aura. In migraine without aura, there is a slowly worsening headache, often on one side of the head, with nausea and sometimes vomiting and/or light and noise sensitivity. In migraine with aura, there may be visual disturbances for up to an hour, followed by a severe, one-sided headache, nausea, vomiting, and sensitivity to light and noise. Other temporary neurological symptoms, such as weakness in one half of the body, may occur.

Diagnosis and treatment 

Diagnosis is usually made from the history and a normal outcome from any physical examinations between attacks. Treatment for an attack is an analgesic drug such as aspirin, paracetamol, or a nonsteroidal anti-inflammatory drug (e.g. ibuprofen), with an antiemetic (anti-vomiting) drug, if needed. If this is not effective, drugs called 5HT 1 agonists, such as sumatriptan, may be prescribed. These drugs are taken as early as possible at the start of an attack, and may prevent the development of a full-blown attack. Sleeping in a darkened room may hasten recovery.

For frequent attacks, preventive treatment may be required. Keeping a diary can help people to identify trigger factors, and prophylactic drugs may be prescribed. Drugs that contain ergotamine may prevent an attack if taken before the headache begins, but are now rarely used; they have largely been replaced by serotonin antagonists such as pizotifen.  . Beta-blocker drugs, or low doses of tricyclic antidepressant drugs (such as amitriptyline), may also be used to prevent attacks. 

Migraine 

Essentials

Epidemiology and clinical features—this episodic disorder affects 12 to 15% of the population in any one year, and about 45% of females over their lifetime; it can be highly disabling. It presents with headache, often throbbing and generally accompanied by other features such as sensitivity to light, sound, or movement, and often with nausea or (less often) vomiting, but none of the features is compulsory.

For example, the migraine aura—visual disturbances with flashing lights or zigzag lines moving across the fields or other neurological symptoms—is reported in only about 25% of patients. It is noteworthy that the word migraine is used to describe the diagnosis—a patient has migraine; as well as an individual attack—a patient is having a migraine. Although a subtle distinction this concept underpins the fact that not all attacks, in all patients, every day, need to conform to standard diagnostic criteria.

Migraine in more detail - technical

Clinical features

Migraine is an episodic brain disorder that affects about 12 to 15% of the population, and can be highly disabling. It has been estimated to be the most costly neurological disorder in the European Union at more than €27 billion per year and its cost to the economy of the United States of America is a staggering US$19.6 billion per year. Migraine presents with a headache generally accompanied by features, such as sensitivity to light, sound, or movement, and often with nausea, or less often vomiting (see Bullet list 1 below). None of the features is compulsory, and indeed, given that the migraine aura, visual disturbances with flashing lights or zigzag lines moving across the fields, or other neurological symptoms, are reported in only about 25% of patients, a high index of suspicion is required to diagnose migraine.

In a controlled study of patients presenting to general practitioners with a main complaint of headache over the previous 3 months, migraine was the diagnosis on more than 90% of occasions, so a high index of suspicion is well rewarded. A headache diary can often be helpful in making the diagnosis, although in reality the diary usually helps more in assessing disability or recording how often patients use acute attack treatments. Phenotyping remains an essentially clinical art, mixing experience and an understanding of the problems likely to present—good headache histories are taken, not given. In differentiating the two main primary headache syndromes seen in clinical practice, migraine at its most simple level is headache with associated features, and tension-type headache is headache that is featureless; furthermore, most disabling headache is probably migrainous in biology. By features is meant throbbing pain, or sensitivity to sensory stimuli—visual, auditory, olfactory—or to head movement itself.

Frequent migraine

If headache with associated features describes migraine attacks, then "headachy " describes the person who has migraines over a lifetime. It is important to realize that the word migraine can describe both the attacks using standard criteria (see Bullet list 1 above) and the disorder itself, which is more than just the attack. People who have migraines (migraineurs) inherit a tendency to have headache that is amplified at various times by their interaction with their environment, the much-discussed ‘triggers’. The brain of the migraineur seems more sensitive to sensory stimuli and to change; and this tendency is notably amplified in women during their menstrual cycle. People who have a migraine may have headache when they oversleep, when tired, when they skip meals, when they overexert, when stressed, or when they relax from a stressor. They are less tolerant to change, and part of successful management is to advise them to maintain regularity in their lives in the knowledge of this fluctuating biology. It is this biology that marks migraine and in clinical practice must over-ride the phenotype of individual headaches.

It has been said that migraine can never occur daily; this is simply not correct. Chronic migraine very definitely occurs and is probably the largest part of the group of headaches known collectively as chronic daily headache that presents to doctors (see below). After making a diagnosis, the second step in the clinical process is to be sure that the disease burden has been captured, how much headache patients have and, more important, what patients cannot do—what is their degree of disability? One can ask the patient directly to get a flavour for this, keep a diary, or get a quick but accurate estimate using the Migraine Disability Assessment Scale (MIDAS), which is well validated and very easy to use in practice.

Principles of management of migraine

After diagnosis the management of migraine begins with an explanation of some aspects of the disorder to the patient:

• ◆ Migraine is an inherited tendency to have headache; this is caused by the patient’s genes, therefore it cannot be cured.
• ◆ Migraine can be modified and controlled by lifestyle adjustment and the use of medicines.
• ◆ Migraine is not life threatening or associated with serious illness, with the exception of women who smoke and use oestrogenic oral contraceptives, but migraine can make life a misery.
• ◆ Migraine management takes time and cooperation, e.g. when a headache diary has to be collected, or enquiry made about the disability.

Nonpharmacological management of migraine

This approach aims to help migrainous patients identify things making the problem worse and encourage them to modify these. Patients need to know that the brain sensitivity that is migraine varies, so that the effect of triggers will vary. Patient associations are often very helpful in supporting migraineurs to identify triggers. The knowledge that there is variability will remove considerable frustration on the patient’s part, and will ring true to most as they have had the experience. The crucial lifestyle advice is to explain to the patient that migraine is a state of brain sensitivity to change. This implies that these people need to regulate their lives: healthy diet, regular exercise, regular sleep patterns, avoiding excess caffeine and alcohol, and, as far as practicable, modifying or minimizing changes in stress. The balanced life with fewer highs and lows will benefit most people who have migraines.

Preventive treatments of migraine

It helps to explain that migraine sufferers have an inherited, noncurable, but manageable problem. To start a preventive they need to have sufficient disability to wish to take a medicine to reduce the affects of the disease on their life. The basis of considering preventive treatment from a medical viewpoint is a combination of acute attack frequency and attack tractability that confers an unacceptable degree of disability. Patients with attacks unresponsive to abortive medications are easily considered for prevention, whereas patients with simply treated attacks may be less obvious candidates. Another important consideration is disease progress. If a patient diary shows a clear trend of an increasing frequency of attacks, it is better to initiate with prevention than wait for the problem to worsen.

A simple rule for frequency might be that for one to two headaches a month there is usually no need to start a preventive, for three to four it may be needed but not necessarily, and for five or more per month prevention should definitely be considered. Options available for treatment are covered in detail in Table 1 and vary somewhat by country. One problem with preventives is that they have fallen into use for migraine from other indications and often bring unwanted or intolerable side effects. It is not clear how preventives work, although it seems likely that they modify the brain sensitivity that underlies migraine. Another key clinical point is that generally each drug should be started at a low dose and gradually increased to a reasonable maximum if there is going to be a clinical effect.

Relatively little has been done in terms of systematic study of patients with more intractable forms of migraine. Neuromodulation approaches are promising, including stimulation of the occipital nerve, and functional imaging studies show that central processing of pain signals in migraine in the thalamus may be modified by such therapies. This is an exciting and developing area.

Acute attack therapies of migraine

Acute attack treatments for migraine can be usefully divided into disease-nonspecific treatments (analgesics and nonsteroidal anti-inflammatory drugs (NSAIDs)) and disease-specific treatments (ergot-related compounds and triptans). It is important to be aware that most acute attack medications seem to have a propensity to aggravate headache frequency and can induce a state of refractory daily or near-daily headache—medication overuse headache. As evidence is gathered, this seems to occur in patients with migraine: either a previous clear history or a family or personal history of headachiness. Codeine-containing compound analgesics are particularly troublesome when available in over-the-counter (OTC) preparations. Patients with migraine should be advised to avoid taking acute attack medicines on more than 2 days a week. A proportion of patients who stop taking regular analgesics will have substantial improvement in their headache with a reduction in frequency; however, for some it will not make any difference. It is crucial to emphasize to the patient that standard preventive medications often simply do not work in the presence of regular analgesic use.

Treatment strategies

Given the array of options to control an acute attack of migraine, how does one start? The simplest approach to treatment has been described as ‘stepped care’. In this model all patients are treated, assuming no contraindications, with the simplest treatment, such as aspirin 900 mg or paracetamol 1000 mg with an antiemetic. Aspirin is an effective strategy, has been proven so in double-blind controlled clinical trials, and is best used in its most soluble formulations. The alternative is a strategy known as ‘stratified care’, by which the physician determines, or stratifies, treatment at the start, based on the likelihood of response to levels of care. An intermediate option may be described as stratified care by attack. This is what many headache authorities suggest, and what patients often do when they have the option: they use simpler options for their less severe attacks, relying on more potent options when their attacks or circumstances demand them (Table 2).

Nonspecific acute migraine attack treatments

As simple drugs, such as aspirin and paracetamol, are cheap and can be effective, dosages should be adequate and the addition of domperidone (10 mg orally) or metoclopramide (10 mg orally) can be very helpful. NSAIDs can very useful when tolerated. Their success is often limited by inappropriate dosing, and adequate doses of naproxen 500 to 1000 mg orally or rectally, with an antiemetic, ibuprofen 400 to 800 mg orally, or tolfenamic acid 200 mg orally can be extremely effective.

Specific acute migraine attack treatments

When simple analgesic measures fail or more aggressive treatment is required, the specific antimigraine treatments are required (Table 3). Although ergotamine remains a useful treatment, it can no longer be considered the treatment of choice in acute migraine. There are particular situations in which ergotamine is very helpful, but its use must be carefully controlled as ergotamine overuse produces dreadful headache in addition to a host of vascular problems. The triptans, serotonin 5HT_1B/1D-receptor agonists, have revolutionized the life of many patients with migraine and are clearly the most powerful option available to stop a migraine attack. They can be rationally applied by considering their pharmacological, physicochemical, and pharmacokinetic features, as well as the formulations that are available. Recent data suggest that combining a triptan with an NSAID can improve efficacy and reduce headache recurrence.

Chronic daily headache

Each of the above primary headache forms can occur very frequently. When a patient experiences headache on 15 days or more a month one can apply the broad diagnosis of chronic daily headache (CDH). CDH is not one thing but a collection of very different problems with different management strategies. Crucially not all daily headache is simply Tension Type Headache (TTH) (Table 4). This is the most common clinical misconception in headache, confusing the clinical phenotype with the headache biotype. Population-based estimates of daily headache are remarkable, demonstrating that about 5% of Western populations have daily or almost daily headache. Daily headache may again be primary or secondary, and it seems clinically useful to consider the possibilities in this way when making management decisions (Table 4). It should be said that population-based studies bear out clinical practice in that a large group of refractory daily headache patients overuse various OTC preparations.

Chronic migraine

Although it is widely accepted that some of the primary headaches, tension type headache (TTH), cluster headache, and paroxysmal hemicrania (PH), have chronic varieties, this question seems to have become unnecessarily troublesome for migraine. Few headache authorities would argue that migraine can never ever be chronic in terms of frequency, but the issue of whether patients with frequent headache, some of which fulfils standard criteria for migraine and some for TTH, have a single migrainous biology is a very vexed one. Given that TTH describes a phenomenology that is indistinct at best, it seems unlikely that all its phenotypes will have a single biological generator.

The concept behind chronic migraine is that some patients who inherit a migrainous biology end up with CDH. The typical patient will have daily headache of a dull, nonspecific type, punctuated by more severe attacks that would often, in isolation, fulfil standard criteria for migraine. In headache speciality clinics this group is dominant, with about 90% of patients in referral headache clinics having chronic migraine, usually with medication overuse. It could be suggested that they have a biologically more difficult problem and this is the basis for their over-representation in referral centres.

If one applies the concepts outlined for TTH (see above) then the diagnosis of chronic TTH (CTTH) is made when the patient has 15 days or more a month of entirely featureless generalized dull or pressure-like pain. When any of the attacks on some days have migrainous features—nausea, photophobia, phonophobia, throbbing, or aggravation with movement—then chronic migraine is more likely to be the diagnosis. Clearly both chronic migraine and CTTH exist. Moreover, some patients must simply have coexisting CTTH and episodic migraine; however, it is simply impossible on clinical or other grounds to determine whom they are. The approach outlined probably overdiagnoses chronic migraine, taking that to be a biological entity, and underdiagnoses the coexistence of CTTH and episodic migraine. The converse would be true—if one diagnoses them all as CTTH and episodic migraine then chronic migraine is missed. In clinical practice the concept of chronic migraine is particularly helpful. Given that the lifestyle advice is identical for both TTH and migraine, and that the range of therapeutic options for preventive treatment in migraine is so much greater, the clinician loses absolutely nothing diagnosing chronic migraine, and the patient has much to gain. For research there are other imperatives.

Management

The management of chronic daily headache (CDH) can be very rewarding. Most patients overusing analgesics respond very sensibly when the problem is explained.

The keys to managing daily headache are:

• ◆ Exclude treatable causes (see Table 4 above )
• ◆ Obtain a clear analgesic history
• ◆ Make a diagnosis of the primary headache type involved

Medication overuse

Medication overuse is defined as consuming an acute attack therapy on 10 days or more per month, except for paracetamol where 15 days is allowed under current guidance. It is essential that analgesic overuse be reduced and eliminated if one is to see the underlying headache phenotype and start to manage the problem. Patients can reduce their use by, as an example, 10% every week or two, depending on their circumstances, or if they wish, and there is no contraindication, by immediate cessation of use. Either approach can be facilitated by first keeping a careful diary over a month or two to be sure of the size of the problem. A small dose of an NSAID, such as naproxen 500 mg twice daily if tolerated, will take the edge off the pain as analgesic use is reduced, as does a greater occipital nerve injection. It is a useful aside that NSAID overuse does not seem to be a common issue in daily headache when they are dosed once or twice daily, whereas with more frequent dosing problems may develop. When the patient has reduced analgesic use substantially a preventive should be introduced. It must be emphasized that preventive therapies most often simply do not work in the presence of analgesic overuse. Thus, the patient must reduce the analgesics or the entire attempt to use the preventive is largely wasted, although this helpful rule must have some limitations that require study. The most common cause of intractability to treatment is the use of a preventive when analgesics continue to be used regularly. For some patients this is very difficult, and often one must be blunt that some degree of pain is inevitable in the first instance if the problem is to be controlled.

Some patients with medication overuse will require admission for detoxification. Broadly this consists of two groups—those who fail outpatient withdrawal or those who have a significant complicating medical indication, such as brittle diabetes mellitus, or complicating medicines, such as opioids, where withdrawal may be problematic as an outpatient. When such patients are admitted acute medications are withdrawn completely on the first day, unless there is some contraindication. Antiemetics, such as domperidone orally or as a suppository, and fluids are administered as required, as well as clonidine for opioid withdrawal symptoms. For acute intolerable pain during the waking hours aspirin (1 g intravenously) is useful and at night chlorpromazine by injection, after ensuring adequate hydration. If the patient does not settle adequately over 3 to 5 days a course of intravenous dihydroergotamine (DHE) can be employed as Raskin described. As time goes by, one feels that DHE is indispensable in this setting. Often 5HT₃ antagonists, such as ondansetron and granisetron, will be required with DHE because it is essential to ensure that the patient does not have significant nausea.

Preventive treatments

The tricylic antidepressants (TCAs), amitriptyline, dosulepin (dothiepin), and nortriptyline, at doses up to 1 mg/kg are very useful in patients with chronic migraine. TCAs are started in low dose (10–25 mg) daily and best given 12 h before the patient wishes to wake up to avoid excess morning sleepiness. The other very useful medications for these patients are the anticonvulsants, such as valproate, topiramate, and gabapentin. For valproate, doses up to 1500 mg daily are used, starting at 200 mg twice daily and increasing to 400 or 600 mg twice daily as tolerated over 2- to 4-week intervals. The blood count and liver enzymes should be checked at baseline and the various side effects explained to patients, especially the fetal abnormalities to women. For topiramate one can start at 25 mg nightly and increase by 25 mg every 10 to 14 days to aim for 50 mg twice daily. For gabapentin the dose is 1800 to 3600 mg daily; it is very well tolerated, although probably less effective from a population viewpoint. For some patients flunarizine can be very effective, as can methysergide or phenelzine. Recently, botulinum toxin type A (onabotulinum toxin) has been shown in a randomized controlled trial to be useful in chronic migraine. One might consider its use, for example, in medically-refractory chronic migraine perhaps after three preventive classes have failed.

New daily persistent headache

New daily persistent headache (NDPH) is a clinically useful concept with a range of important possible causes because some are very treatable (Table 5). From a nosological point of view all that is mentioned here could be placed within various categories of the IHS classification, and indeed the IHS refers to primary NDPH. However, the term as employed here serves both patients and clinicians by highlighting a group of conditions, some of which are curable, and encompasses the IHS term under the primary featureless form of NDPH.

The patient with NDPH presents with a history of headache on most if not all days, starting from one day to the next. The onset of headache is abrupt, often from one moment to the next, but at least in less than a few days with three suggested as an upper limit. The typical history is for the patient to recall the exact day and circumstances, so from one moment to the next a headache develops that never leaves them. This presentation triggers certain key questions about the onset and behaviour of the pain. The pressing issues arise from considering the secondary headache possibilities. Although subarachnoid haemorrhage is listed for some logical consistency, as the headache may certainly come on from one moment to the next, it is not likely to produce diagnostic confusion in this group of patients. Suffice it to say that subarachnoid haemorrhage is so important that it must always be considered if only to be excluded, either by history or by appropriate investigation.

Primary NDPH

Initial descriptions of primary NDPH recognized that it occurs in both males and females. Migrainous features were common, with unilateral headache in about one-third and throbbing pain in about one-third. Nausea was reported in about one-half of the patients, as were photophobia and phonophobia. A number of these patients have a previous history of migraine, but not more than one might expect given the population prevalence of migraine. It is remarkable that the initial report noted that 86% of patients were headache free at 24 months. It is general experience among those interested in headache management that primary NDPH is perhaps the most intractable and least therapeutically rewarding form of headache. In general one can classify the dominant phenotype—migraine or TTH—and treat with preventives according to that subclassification.

Bullet list 2 Other secondary headaches

Secondary NDPH

The secondary causes of the syndrome of NDPH are worthy of consideration, because they have distinctive clinical pictures that can guide investigation (Bullet list 2 above).

Cervicogenic headache

It is a time-honoured concept that the neck is responsible for many headaches. Unfortunately, as with much of history, the good story is often ruined by the facts. Although there is little doubt that there is a rich overlap between the innervation of intracranial pain-producing structures by the ophthalmic division of the trigeminal nerve, and the posterior fossa and high cervical innervation by branches especially of the C2 dorsal root, causality is another issue. The Headache Classification Committee recognizes that head pain can arise from the neck and labels this ‘cervicogenic headache’. The term has been used by others to define a syndrome that is so poorly described as to be useless in practice. Most patients with neck discomfort and headache referred to speciality practice have migraine. They will have neck stiffness or discomfort as a premonitory symptom that can clearly persist in all stages of the attack. They may respond to local therapies, such as greater occipital nerve injection; however, this implies no more than triggering, and is to be expected. The pursuit of neck pathology and the treatment of patients with migraine by manipulative or physical means have no support in the controlled literature, and are rarely of long-lasting value.

Back to top