Definition and Overview
Migraine is a disease characterized by recurrent, moderate to severe throbbing headaches. According to the International Headache Society classification criteria, a pulsating headache lasting 4 to 72 hours occurs on one side of the head. It is accompanied by nausea, vomiting, and hypersensitivity to light and sound.
According to the 2019 Global Burden of Disease Study, approximately 1.1 billion people worldwide suffer from migraines. Among neurological diseases, it has the second highest degree of disability. The domestic prevalence is reported to be approximately 6-17%, and it is most common in women in their 30s and 40s.
Epidemiology
The annual prevalence of migraine worldwide is approximately 12-15%. It is about three times higher among women (17-18%) than among men (6-8%). These gender differences become evident after puberty, and fluctuations in the female hormone estrogen are suggested to be the main cause.
Migraine has the highest prevalence among people aged 25 to 55 years. This period carries a significant social burden because it overlaps with the core age group for economic activity. The World Health Organization classified migraine as one of the most disabling diseases. The annual economic loss due to migraines in the United States is approximately $36 billion.
cause
The core cause of migraines is excessive activation of nerves around blood vessels in the membrane (dura) surrounding the brain. When this nerve is stimulated, a substance that causes pain is secreted. The representative one among them is calcitonin gene-related peptide (CGRP). This substance dilates blood vessels and causes an inflammatory response in the surrounding area, causing headaches.
Pain signals are transmitted to the brain's sensory centers and are felt as a headache. The brain of a migraine patient is usually sensitive to sensory stimulation.
In some patients, visual symptoms (aura), such as flashing lights or zigzag patterns in the field of vision, appear before the onset of a headache. This is a phenomenon that occurs when changes in the electrical activity of brain nerve cells spread like waves.
As migraines recur, the brain's pain processing circuitry becomes increasingly sensitive. As this condition worsens, you may feel pain even from stimuli that normally do not cause pain, such as washing your face or combing your hair.
symptoms
The main symptoms of migraine are:
Throbbing, pulsating pain on one side (or sometimes both) of the head. Pain intensity is moderate to severe and is worsened by daily activities such as walking or climbing stairs.
Nausea and vomiting are often accompanied by headaches. Sensitivity to bright lights or loud sounds increases, and some patients also become sensitive to smells.
Before a headache attack, prodromal symptoms such as fatigue, irritability, changes in appetite, and stiff neck may appear a day or two before.
diagnosis
The diagnostic criteria for migraine according to the 3rd edition of the International Headache Society Classification are as follows:
- Five or more headache attacks that meet the conditions below:
- Headache lasting 4 to 72 hours (if untreated or treatment failed)
- If your headache is 2 or more of the following: (1) One head; (2) throbbing, (3) moderate to severe intensity; (4) worsened by daily activities
- Headaches accompanied by one or more of the following: (1) nausea or vomiting; (2) Hypersensitivity to light and sound
- Not explained by another disorder
Migraine is usually diagnosed through history taking and neurological examination. Brain imaging may be performed if necessary to rule out other causes.
Classification
Migraines are largely divided into two types.
Migraines without aura account for approximately 70-75% of all cases. Migraine with aura occurs in approximately 25-30% of cases. Visual, sensory, and speech abnormalities appear for 5 to 60 minutes before or simultaneously with the headache.
Chronic migraine is when headaches persist for more than 15 days a month for more than 3 months, and more than 8 of those days show migraine patterns. Approximately 2.5-3% of regular migraine patients develop chronic migraine each year, and overuse of painkillers is a major risk factor.
trigger factor
The main triggers of migraine attacks have been reported to be stress (about 70%), lack of or too much sleep (about 50%), menstrual cycle (about 60% of women), weather changes (about 40%), certain foods (about 25%), and strong lights, noises, and smells.
Triggers vary from person to person. Keeping a headache diary to identify your own triggers is the first step in managing migraines.
Progress and Complications
In most cases, migraines are not life-threatening, but they significantly reduce quality of life. If left without proper treatment, the frequency of attacks may gradually increase and progress to chronic migraine.
Taking painkillers repeatedly for more than 10 days a month can cause medication overuse headaches, which cause headaches to become more frequent. Migraine with aura accompanied by visual symptoms has rarely been reported to be associated with an increased risk of stroke, so accurate diagnosis and management are necessary.
life guide
Regular sleep is important. It is best to go to bed and wake up at the same time every day and not change your sleep pattern significantly even on weekends.
Eat regular meals and avoid dehydration. Caffeine can help relieve headaches in small amounts, but excessive intake or sudden cessation can cause headaches.
It is important to keep a headache diary to identify your triggers and avoid them. Regular aerobic exercise (3-5 times a week, 30 minutes or more) helps prevent migraines.