Migraine is a common primary headache disorder that reduces the ability to work. Epidemiological studies have shown the high prevalence of migraine and its socioeconomic and personal impact. Currently, the World Health Organization (WHO) ranks migraine as the 19th most common disease worldwide that decreases work capacity. Approximately 80% of migraineurs complain of reduced work capacity when they have a headache, and approximately 50% complain of severe headaches that cause extreme restriction of movement and require bed rest. The prevalence of migraine varies by age, with the highest prevalence in the 30-45 age group. However, after puberty, the prevalence is higher in females than in males. A study in the United States found that the prevalence of migraine was 18.2% for women and 6.5% for men, with the prevalence increasing between the ages of 8 and 40 and decreasing for both men and women after the age of 40.
[Phenomenon].
Migraine can be divided into four different phases – the prodromal symptom phase, the aura phase, the headache phase, and the recovery phase. However, not all of these four phases are present for a particular patient and a particular attack. For example, a patient may have a headache without an aura, or an aura without a headache. Migraine can be divided into two main subtypes – migraine with aura and migraine without aura. The same patient can have both types of migraine.
Prodromal symptoms
Some patients have prodromal symptoms that occur hours or days before the headache, but are not universal. Prodromal symptoms include fatigue, difficulty concentrating, stiff neck, sensitivity to light or sound, nausea, blurred vision, yawning, pallor, irritability, overexcitement, depression, craving for specific foods, etc.
Aura
Migraine aura mostly occurs in the occipital visual cortex. The visual aura often appears as a flash, a dark spot, a zigzag flash near the point of gaze, which may gradually expand to the right or left and then may appear as a jagged dark spot. In some cases, there may be only a dark spot without a flash, which is often interpreted as the beginning of an acute attack, but on closer inspection, the dark spot usually gradually expands.
Aura occurring in other cortical layers is rare. Unilateral sensory abnormalities manifest as a slow moving pins and needles sensation from the onset that can affect larger or smaller parts of one side of the body and face, which may be followed by numbness, but numbness may also be the only symptom. A much less common aura is a speech disorder, which usually presents as difficulty with speech, but is often difficult to classify. Aura also includes transient temporal lobe symptoms such as olfactory hallucinations – smelling burnt, cooking or unpleasant odors. Aura symptoms usually occur in succession to each other, beginning with visual symptoms, followed by sensory symptoms and speech difficulties, or in the opposite or other order.
Auras of basal migraine include dysarthria, vertigo, tinnitus, hearing loss, diplopia, visual symptoms in the temporal and nasal visual fields of both eyes, ataxia, decreased level of consciousness, and bilateral sensory abnormalities. Aura also includes weak mobility in familial hemiplegic migraine or sporadic hemiplegic migraine.
Headache presentation
About 2/3 of migraines are predominantly unilateral headaches that can shift from one side to the other in the same attack. Although most migraineurs have unilateral headaches, bilateral headaches do not preclude the diagnosis of migraine. The headache is often located in the frontotemporal region, but can also be located behind the eyes, and can radiate backward to the occipital lobe and upper neck, and even to the lower neck and shoulders.
Migraines often begin as a dull ache and then become pulsating pain, which is a characteristic feature of migraines. However, many migraineurs have never had a throbbing headache. Migraines are often moderate to severe and can interfere with the patient’s daily activities. Daily physical activities such as walking or climbing stairs can aggravate the headache. As a result, migraineurs prefer to stay in bed with no movement of the head or body.
Migraine attacks are often accompanied by loss of appetite, nausea, vomiting, photophobia, fear of sound, and dislike of certain smells. Patients prefer to stay in a quiet, dark room. Migraineurs may also have dizziness and mental changes, such as difficulty expressing themselves verbally and cognitive impairment.
Recovery period
Migraineurs often feel fatigued and sleepy for several days after the headache, as well as inattentive, irritable, depressed, with scalp tenderness or loss of appetite. A small number of patients may experience euphoria and cravings for certain foods. In general, the symptoms of the recovery period are similar to those of the prodromal period.
Triggers
Different attacks of migraine have different triggers, and different patients have different triggers or can have no obvious trigger. Common triggers for migraine attacks include
(1) Hormonal changes (menstruation, oral contraceptives)
(2) dietary factors (alcohol, nitrite-rich meats, MSG, chocolate, etc.)
(3) Environmental factors (flashing lights, visual stimuli, odors, weather changes)
(4) Psychological factors (stress, anxiety, depression, worry)
(5) Drugs (nitroglycerin, reserpine, estrogen, etc.)
(6) Other factors (lack of sleep, too much sleep, fatigue, head trauma).
[Diagnosis].
The most important element in the diagnosis of migraine is the medical history, and the important elements are.
(1) Age of onset.
(2) Frequency and duration of attacks.
(3) The location, nature and degree of the headache.
(4) aura.
(5) concomitant symptoms.
(6) The effect of activity on headache.
(7) Triggering and relieving factors. Patients are advised to keep a headache diary to aid in diagnosis.
Migraine is divided into two main subtypes – migraine without aura and migraine with aura, with the former being the most common subtype. Table 2 lists the IHS diagnostic criteria for migraine without aura. In children, migraine attacks usually last 1 to 72 hours, which is shorter than in adults.
If the headache following a typical aura does not meet the criteria for migraine without aura, then the diagnosis should be “typical aura of headache without migraine”. As long as there is weak mobility during the aura, the diagnosis should be hemiplegic migraine. Familial hemiplegic migraine (FHM) is diagnosed if the patient’s first-degree relatives have similar attacks, otherwise sporadic hemiplegic migraine is diagnosed. For basal migraine, migraine aura symptoms clearly originate from the brainstem and/or bilateral hemispheres, but there is no weakness of mobility. Its aura symptoms include at least 2 of the following symptoms.
(1) Dysarthria.
(2) Vertigo.
(3) Tinnitus.
(4) Hearing loss.
(5) diplopia.
(6) visual symptoms in the temporal and nasal visual fields of both eyes.
(7) ataxia.
(8) decreased level of consciousness.
(9) Bilateral sensory abnormalities.
[Treatment].
There is no cure for migraine, but most patients can find relief with a combination of behavioral and pharmacological treatments. Migraineurs are advised to lead a regular and healthy life and avoid triggering factors. Psychological and physiological techniques can be used to combat stress. Acupuncture, massage, relaxation exercises, biofeedback and cognitive-behavioral therapy can help treat migraine. Chinese medicine is also widely used, but more evidence-based medical evidence is needed. The pharmacological treatment of migraine includes acute attack treatment and preventive treatment.
1. Treatment of acute attacks
The purpose of treatment in the acute phase of migraine is to stop the headache attack as soon as possible, eliminate the accompanying symptoms and restore the ability of daily activities. Drugs can be divided into two categories – non-specific drugs and specific drugs, the former refers to painkillers with analgesic effect but not specific for migraine; the latter refers to drugs with anti-migraine effect but no general analgesic effect.
Non-specific drugs include.
(1) Non-steroidal anti-inflammatory drugs (NSAIDs): a combination containing aspirin, ibuprofen, naproxen sodium, tromethamine or acetaminophen, for which there is much evidence-based medical evidence.
(2) Sedatives such as barbiturates.
(3) Opioids. Barbiturates and opioids are only appropriate for severe cases where other treatments have failed because of their addictive properties.
Atopic drugs include.
(1) Ergot analogues such as ergotamine and dihydroergotamine, and the commonly used domestic ergot preparation is caffeine angle, a compound of ergotamine and caffeine.
(2) Traptans, which are 5-HT1B/1D receptor agonists and can partially agonize 5-HT1F receptors, are marketed domestically as sumatriptan and zolmitriptan, with a variety of different preparations available abroad. Attention should be paid to the side effects of idiosyncratic drugs, for example, they all have vasoconstrictive effects, so patients with coronary heart disease, ischemic cerebrovascular disease and uncontrolled hypertension should not use these agents.
Early and adequate treatment after the onset of a migraine attack is more effective in relieving the headache. However, too many pain relievers should not be used to avoid medication overload headache (MOH).
In addition, antiemetics and pro-gastrointestinal agents such as metoclopramide and domperidone can reduce concomitant symptoms and help the absorption and action of other medications. Glucocorticoids can be used for severe migraine attacks such as migraine persistence.
2. Prophylactic treatment
The purpose of preventive treatment for migraine is to reduce the frequency of migraine attacks, reduce the severity of headache, reduce the reduction of labor ability, and improve the efficacy of treatment during acute attacks.
Indications for preventive treatment.
(1) Migraine attacks greater than 2 episodes/month or headache days averaging more than 4 days/month within the past 3 months.
(2) Failure of acute phase treatment or inability to perform acute phase treatment due to drug side effects and contraindications.
(3) Application of painkillers greater than 2 times/week.
(4) Special conditions, such as hemiplegic migraine, prolonged migraine with aura and migrainous cerebral infarction.
(5) Menstrual migraine.
(6) Patient’s orientation.
The principles of prophylactic treatment are as follows.
(1) Combined MOH should be ruled out, as such conditions are not effective for prophylactic medication, and if MOH is suspected, withdrawal of pain medication for 2 months is recommended to confirm the diagnosis, and if the headache is still severe after 2 months of withdrawal, prophylactic treatment is necessary.
(2) Selection of drugs with established efficacy and few side effects according to the principle of individualization, pharmacological action and side effects of the drug (to be evidenced).
(3) The important point is to start with small doses and increase them slowly until a therapeutic amount is reached or unacceptable side effects occur.
(4) Evaluate the efficacy of prophylactic drugs within 4 to 8 weeks.
(5) Treatment in full doses (usually 3 to 6 months).
(6) Ensuring that patients have the right expectations of preventive therapy will help improve their compliance, and a 50% reduction in migraine attack frequency is considered effective.
Commonly used prophylactic medications are.
(1) beta-adrenergic receptor blockers, not all agents are effective in preventing migraine; propranolol and timolol have more evidence-based medical evidence, and nadolol, atenolol and metoprolol are also effective.
(2) Calcium channel blockers, with more evidence-based medical evidence for flunarizine.
(3) Antiepileptic drugs such as sodium valproate and topiramate.
(4) tricyclic antidepressants such as amitriptyline
(5) 5-HT blockers such as phenothiazine.
(6) Others: high-dose riboflavin (vitamin B2), magnesium, botulinum toxin A, and Chinese medicine, which have not yet reached consensus, although they have begun to be used.