Prevention of migraines

Preventive (also called prophylactic) treatment of migraines can be an important component of migraine management. Such treatments can take many forms, including everything from taking certain drugs or nutritional supplements, to lifestyle alterations such as increased exercise and avoidance of migraine triggers.

The goals of preventive therapy are to reduce the frequency, painfulness, and/or duration of migraines, and to increase the effectiveness of abortive therapy.^[1] Another reason to pursue these goals is to avoid medication overuse headache (MOH), otherwise known as rebound headache, which is a common problem among migraneurs. This is believed to occur in part due to overuse of pain medications, and can result in chronic daily headache.^[2][3]

Acupuncture

Cochrane reviews have found that acupuncture is effective in the treatment of migraines.^[4] The use of "true" acupuncture is not more efficient than sham acupuncture, however, both "true" and sham acupuncture appear to be more effective than routine care in the treatment of migraines, with fewer adverse effects than prophylactic drug treatment.^[5]

Behavioral treatments

Many physicians believe that exercise for 15–20 minutes per day is helpful for reducing the frequency of migraines.^[6]

Sleep is often a good solution if a migraine is not so severe as to prevent it, as when a person awakes the symptoms will have most likely subsided.

Diet, visualization, and self-hypnosis are also alternative treatments and prevention approaches.

Sexual activity has been reported by a proportion of male and female migraine sufferers to relieve migraine pain significantly in some cases.^[7]

In many cases where a migraine follows a particular cycle, attempting to interrupt the cycle may prolong the symptoms. Letting a headache "run its course" by not using painkillers can sometimes decrease the length of an episode. This is especially true of cases where vomiting is common, as often the headache will subside immediately after vomiting. Curbing the pain may delay vomiting, and prolong the headache.^{[citation needed]}

Gluten-Free Diet

Some individuals have a condition called celiac disease (or "gluten intolerance") that results in the body incorrectly processing gluten. Studies have suggested that 4% ^[8] of migraine sufferers have celiac disease, and for those who do, decreasing gluten intake may significantly reduce migraine frequency.^[9] Celiac disease and gluten sensitivity may be an underlying cause of migraines in some patients, and a gluten-free diet has been demonstrated to reduce, if not completely eliminate, migraines in these individuals. A study of 10 patients with a long history of chronic headaches that had recently worsened or were resistant to treatment found that all 10 patients were sensitive to gluten. MRI scans determined that each had inflammation in their central nervous systems caused by gluten-sensitivity. Seven out of nine of these patients that went on a gluten-free diet stopped having headaches completely.^[10] Another study showed that migraneurs were 10 times more likely than the general population to have celiac disease, and that for migraneurs with celiac disease, a gluten-free diet improved blood-flow to the brain and either eliminated migraines or reduced migraine frequency, duration, and intensity.^[9]

Herbal and nutritional supplements

Butterbur

Native butterbur contains some carcinogenic compounds, but a purified version, Petadolex, does not.^[11] A systematic review of two trials totalling 293 patients (60 and 233 patients) showed "moderate evidence of effectiveness ... for a higher than the recommended dose of the proprietary Petasites root extract Petadolex in the prophylaxis of migraine."^[12]

Cannabis

Cannabis was a standard treatment for migraines from 1874 to 1942.^[13] It has been reported to help people through an attack by relieving the nausea and dulling the head pain, as well as possibly preventing the headache completely when used as soon as possible after the onset of pre-migraine symptoms, such as aura.^[13]

Feverfew

The plant feverfew (Tanacetum parthenium) is a traditional herbal remedy believed to reduce the frequency of migraine attacks. A number of clinical trials have been carried out to test this claim, but a 2004 review article concluded that the results have been contradictory and inconclusive.^[14]

Manual Therapy

A systematic review stated that chiropractic manipulation, physiotherapy, massage and relaxation might be as effective as propranolol or topiramate in the prevention of migraine headaches; however, the research had some problems with methodology.^[15]

Medical devices

Neurostimulation

Neurostimulation initially used implantable neurostimulators similar to pacemakers for the treatment of intractable chronic migraines^[16][17] with encouraging good results. But the needed surgery with implantable neurostimulators is limiting the indication to sever cases.^[18]

Transcranial Magnetic Stimulation (TMS)

At the 49th Annual meeting of the American Headache Society in June 2006, scientists from Ohio State University Medical Center ^[19] presented medical research on 47 candidates that demonstrated that TMS — a medically non-invasive technology for treating depression, obsessive compulsive disorder and tinnitus, among other ailments — helped to prevent and even reduce the severity of migraines among its patients. This treatment essentially disrupts the aura phase of migraines before patients develop full-blown migraines.^[20]

In about 74% of the migraine headaches, TMS was found to eliminate or reduce nausea and sensitivity to noise and light ^[21]. Their research suggests that there is a strong neurological component to migraines. A larger study will be conducted soon to better assess TMS's complete effectiveness.^[22]

In June 2008, a hand-held apparatus designed to apply TMS as a preemptive therapy to avert a migraine attack at the onset of the aura phase was introduced in California.^[23]

Biofeedback

Biofeedback has been used successfully by some to control migraine symptoms through training and practice.^[24]Biofeedback helps patient to be conscious of some physiologic parameters to control them and try to relax. This method is considered to be efficient for migraine prevention.^[25][26] A recent clinical trial has demonstrated that simple use of biofeedback as a relaxation technique has similar efficacy for migraine treatment to sophisticated sessions in clinics.^[27]

Hyperbaric oxygen therapy

Hyperbaric oxygen therapy has been used successfully in treating migraines.^[28][29][30] This suggests that sufferers might be treated during an attack with a hyperbaric chamber of some sort, such as a Gamow bag (as is done in the treatment of "The Bends" and altitude sickness).

Prescription drugs

A 2006 review article by S. Modi and D. Lowder offers some general guidelines on when a physician should consider prescribing drugs for migraine prevention:

Following appropriate management of acute migraine, patients should be evaluated for initiation of preventive therapy. Factors that should prompt consideration of preventive therapy include the occurrence of two or more migraines per month with disability lasting three or more days per month; failure of, contraindication for, or adverse events from acute treatments; use of abortive medication more than twice per week; and uncommon migraine conditions (e.g., hemiplegic migraine, migraine with prolonged aura, migrainous infarction). Patient preference and cost also should be considered. ...Therapy should be initiated with medications that have the highest levels of effectiveness and the lowest potential for adverse reactions; these should be started at low dosages and titrated slowly. A full therapeutic trial may take two to six months. After successful therapy (e.g., reduction of migraine frequency by approximately 50 percent or more) has been maintained for six to 12 months, discontinuation of preventive therapy can be considered. ^[1]

Preventive medication has to be taken on a daily basis, usually for a few weeks, before the effectiveness can be determined. Supervision by a neurologist is advisable. A large number of medications with varying modes of action can be used. Selection of a suitable medication for any particular patient is a matter of trial and error, since the effectiveness of individual medications varies widely from one patient to the next. Often preventive medications do not have to be taken indefinitely. Sometimes as little as six months of preventive therapy is enough to "break the headache cycle" and then they can be discontinued.

The most effective prescription medications include several drug classes:

Beta blockers such as propranolol and atenolol.

A meta-analysis by the Cochrane Collaboration of nine randomized controlled trials or crossover studies, which together included 668 patients, found that propranolol had an "overall relative risk of response to treatment (here called the 'responder ratio')" was 1.94.^[31]

Anticonvulsants

Anticonvulsants such as valproic acid and topiramate. A meta-analysis by the Cochrane Collaboration of ten randomized controlled trials or crossover studies, which together included 1341 patients, found anticonvulsants had an "2.4 times more likely to experience a 50% or greater reduction in frequency with anticonvulsants than with placebo" and a number needed to treat of 3.8.^[32] However, concerns have been raised about the marketing of gabapentin.^[33]

Antidepressants

Tricyclic antidepressants (TCAs) such as amitriptyline and the newer selective serotonin reuptake inhibitors (SSRIs) such as fluoxetine are sometimes prescribed.^[34] Tricyclic antidepressants have been found to be more effective than SSRIs.^[35] A meta-analysis by the Cochrane Collaboration found selective serotonin reuptake inhibitors are no more effective than placebo.^[36] Another meta-analysis found benefit from SSRIs among patients with migraine or tension headache; however, the effect of SSRIs on only migraines was not separately reported.^[37] A randomized controlled trial found that amitriptyline was better than placebo and similar to propranolol.^[38]

A wide range of other pharmacological drugs have been evaluated to determine their efficacy in reducing the frequency or severity of migraine attacks.^[34] These drugs include beta-blockers, calcium antagonists, neurostabalizers, nonsteroidal anti-inflammatory drugs (NSAIDs), tricyclic antidepressants, selective serotonin reuptake inhibitors (SSRIs), other antidepressants, and other specialized drug therapies.^[34] The US Headache Consortium lists five drugs as having medium to high efficacy: amitriptyline, divalproex, timolol, propranolol and topiramate.^[34] Lower efficacy drugs listed include aspirin, atenolol, fenoprofen, flurbiprofen, fluoxetine, gabapentin, ketoprofen, metoprolol, nadolol, naproxen, nimodipine, verapamil and Botulinum A.^[34] Additionally, most antidepressants (tricyclic, SSRIs and others such as Bupropion) are listed as "clinically efficacious based on consensus of experience" without scientific support.^[34] Many of these drugs may give rise to undesirable side-effects, or may be efficacious in treating comorbid conditions, such as depression.

Other drugs

• Methysergide was withdrawn from the US market by Novartis, but is available in Canadian pharmacies. Although highly effective, it has rare but serious side effects, including retroperitoneal fibrosis.^[39]
• Methylergometrine remains available in the US and is an active metabolite of methysergide. It is thought to carry the same risks and benefits as methysergide but has not been widely studied in migraine.
• Memantine, which is used in the treatment of Alzheimer's Disease, is beginning to be used off label for the treatment of migraines. It has not yet been approved by the FDA for the treatment of migraines.
• Aspirin can be taken daily in low doses such as 80 mg. The blood thinners in ASA have been shown to help some migraineurs, especially those who have an aura.
• Placebo is as effective as adding propanolol to patients not adequately controlled on topiramate. In a randomized controlled trial, both groups reduced their days with migraine by half.^[40]

Surgical treatments

Botulinum neurotoxin (Botox) injections have been approved in the US and UK for prevention of chronic migraines,^[41] but do not appear to work for episodic migraines.^[42] Several invasive surgical procedures are currently under investigation. One involves the surgical removal of specific muscles or the transection of specific cranial nerve branches in the area of one or more of four identified trigger points.^[43] There also appears to be a causal link between the presence of a patent foramen ovale and migraines.^[44][45]

Migraine surgery which involves decompression of certain nerves around the head and neck may be an option in certain people who do not improve with medications.^[46] It is only effective in those who respond well to Botox injections in specific areas.^[43][47] A major advantage of migraine surgery is that, with the correct diagnostic techniques, a definite diagnosis can be made before the surgery is undertaken. Once a positive diagnosis has been made, the results of surgery are outstanding and provide permanent pain relief, as well as relief from the associated symptoms, such as nausea, vomiting, light sensitivity, and sound sensitivity. Surgical cauterization of the superficial blood vessels of the scalp (the terminal branches of the external carotid artery) is only carried out if it has been established with certainty that these vessels are indeed the source of pain. It is a safe and relatively atraumatic procedure which can be performed in a day facility.^[48]

There is also evidence that the correction of a congenital heart defect, patent foramen ovale (PFO), reduces migraine frequency and severity.^[49] Recent studies have advised caution, though, in relation to PFO closure for migraines, as insufficient evidence exists to justify this dangerous procedure.^[50][51]

Trigger avoidance

General dietary restriction has not been demonstrated to be an effective approach to treating migraine.^[52]

References