Millions of individuals—predominantly women— are afflicted by migraines. Despite its prevalence, there remains much to uncover about the causes of this condition. What can we do about this incapacitating headache that plagues so many?
Migraine is a medical condition characterized by severe recurring headaches that can sometimes completely incapacitate the patient. The pain typically occurs on one side of the head and lasts from a few hours to several days. Migraines are often accompanied by nausea, vomiting and hypersensitivity to light, sound and smell. About one-third of migraine sufferers also experience a visual disturbance, known as visual aura, which precedes the migraine and signals its onset.
Different patients experience migraine differently, with marked differences in the frequency of its appearance, symptoms and duration, posing challenges for diagnosis. Many patients do not seek medical attention, assuming that they are just experiencing a regular headache, thus most cases likely remain undiagnosed.
Migraine diagnosis involves assessing the frequency, duration, location and severity of the headache. Different findings may indicate different types of migraine.
Migraine Duration
A typical migraine attack consists of four potential stages, but not all are necessarily experienced every time by each patient. The first stage, known as prodrome, usually precedes the pain by several hours or even by a few days, with about 60% of patients experiencing it. The symptoms may include extreme mood swings, irritability, depression or euphoria, fatigue, cravings for certain food types, muscle stiffness, constipation and heightened sensitivity to smells and loud sounds.
The next stage is aura, characterized by visual difficulties, such as flashing lights in the visual field and blurriness. There have also been reports of stabbing pains in the sides of the body and face, followed by a feeling of numbness. Other possible symptoms include disturbances in speech, and in severe cases, motor impairments.
The third stage is pain, typically experienced on one side of the head and gradually intensifying. Strenuous physical activity tends to exacerbate the intensity of the pain, which is often accompanied by a feeling of nausea, to the point of vomiting, and increased sensitivity to external stimuli - light, sound and smell, driving many patients to seek relief in a dark, quiet room. Some may also experience dizziness and confusion.
The final stage, postdrome, can include a range of symptoms that appear after the severe headache subsides. Some patients report dull lingering pain in the area where they experienced the original pain, cognitive heaviness which may last several days after the headache subsides, and feelings similar to a hangover. Conversely, others report feeling unusually refreshed or euphoric after an attack.
The Causes
Migraines are currently understood to result from a combination of environmental and genetic factors. About two-thirds of cases exhibit a family history of migraines. Twin studies further support the genetic component hypothesis for migraines.
However, to date, identifying specific genes involved in migraines has proven challenging. The difficulty is partly due to the significant variation among migraine sufferers and the complex combinations of symptoms, making it challenging to find a sufficient number of candidates with similar collections of symptoms. Nevertheless, some genes linked to migraine have indeed been identified. These genes are involved in the regulation of the neurotransmitter glutamate, lipoprotein receptors (lipoproteins are large fatty complexes that facilitate blood cholesterol transport), and a receptor involved in transmitting cold and pain sensations.
Hormonal changes may play a role in migraine frequency. While boys experience more migraines during adolescence, women are three times more likely to experience them than men during adulthood. Most migraine sufferers report triggers preceding the attack, usually occurring the day before, including hunger, a lack of sleep, and particularly, according to patient reports, mental stress.
Very little is known about the neural mechanism underlying migraines, but currently, it is estimated that migraines are a neurovascular disorder, meaning that they involve both the nervous and vascular systems. Abnormal activity seems to begin in the brain with intense nerve cell activity, spreading to the blood vessels and resulting in decreased blood flow, which is followed by a reciprocal increase. Opinions differ regarding the contribution of the nerve cells versus blood vessels, and we currently lack enough information to accurately determine the contribution of each system or to understand how migraine attacks initiate.
The symptoms include sensitivity to light and vision problems. A woman having a migraine attack | Photo: Science Photo Library
Treatment and Prevention
There are three primary treatment approaches for migraines: avoiding known triggers, using medication during the attack and taking preventive medication. The first approach is feasible only when specific triggers, such as certain foods or environmental stimuli such as strong light or sound that trigger migraine in a particular patient., are identified. These triggers can then be avoided or at least minimized. Other triggers may be unavoidable, such as menstruation in women, changes in the weather, or mental stress.
Once a migraine attack begins, several medications are available to relieve symptoms. The first type includes medications from the triptan family, such as sumatriptan. These substances bind to receptors of the neurotransmitter serotonin in the brain and blood vessels and activate these receptors, alleviating nausea and pain. Their effectiveness increases the closer they are taken to the onset of an attack. Possible side effects include hot flashes, a sensation of pressure in the body, and itching. In very rare cases, triptans may lead to coronary heart disease due to a blocked artery. If one triptan is ineffective, another medication from this group may still provide relief.
Another medication option is dihydroergotamine, administered as a spray or by injection. Its mechanism of action is similar to that of triptans, but also involves binding to dopamine and adrenaline receptors, which are then activated. Nausea is a common side effect.
In addition to specific migraine medications, non-steroidal anti-inflammatory drugs (NSAIDs) such as aspirin and ibuprofen (the active ingredients in Advil and Nurofen) can help alleviate migraine pain.
Patients with particularly high migraine frequency and severity may consider taking preventive medications on a regular basis. This is also advisable for patients who cannot use attack-specific medications due to health reasons or those receiving other medications that should not be combined with migraine-relieving drugs. Those with unavoidable triggers might consider regular or strategically timed preventive medication. An example of a type of medication that could be effective in such cases is amitriptyline, which delays the reabsorption of the neurotransmitter serotonin and affects the mobility of both serotonin and noradrenaline.
According to the World Health Organization there is a significant gap in knowledge among medical professionals regarding headache disorders,attributable to the scant time dedicated to this topic during medical training. This gap strongly impacts the rate of diagnosis of migraines, particularly those without aura.
This lack of awareness is also prevalent among the general public, which does not place much importance on migraines, dismissing them as “just a passing headache” that is neither life-threatening nor contagious. This perception also influences the frequency at which migraine sufferers seek medical advice or treatment; some are even unaware that effective medical treatments for migraines exist.
Furthermore, many governments, intent on reducing healthcare costs, fail to acknowledge the significant burden migraines impose on society—even with respect to their economic impact on the workforce. For instance, it is estimated that in Britain alone, migraines and other headaches result in the loss of 25 million work and study days annually.