Medical Corner: Migraine Headaches
Drs. Anita Murcko and Carol Foster explore the definition, causes, and fixes for migraine headaches.
By Anita C. Murcko, MD, FACP, and guest Carol Foster, MD
As a primary-care internal medicine physician, I explore headaches with patients and colleagues. Most are not emergencies or results of serious underlying illnesses. Most headaches are tension headaches, which are worst when under stress and are often associated with tightness or pain in the muscles of the neck, back, and shoulders. Symptom descriptions range from an uncomfortable pressure, a band-like feeling around the head, and pain "all over my head," to a dull, burning sensation over the eyes. A recent reduction in caffeine can result in a caffeine-withdrawal headache (Starbucks to the rescue). Talking to the patient, her primary care doctor, neurologist, allergist, or otolaryngologist about the headache, its signs, symptoms, and triggers, and asking, "What else is going on?" is our most important role. A careful history and appropriate referral will result in a prompt diagnosis and relief for our many patients who suffer from the undifferentiated headache.
What is a 911 headache? Any head pain that is sudden, severe, or new requires immediate evaluation. Headaches associated with stroke symptoms (sudden weakness, numbness, inability to move, slurred speech, vision changes, confusion, behavior changes, or seizure) are emergencies. If a headache is associated with severe eye pain, think about closed-angle glaucoma (a rare emergency), but if the eye pain is stabbing, sharp, and accompanied by a runny eye or nostril, then cluster headache syndrome is more likely the cause. If there has been a recent head injury and the headache's getting a lot worse, it might be due to a brain hematoma. A headache with stiff neck, fever, vomiting, drowsiness, or rash might be meningitis or a complicated sinusitis. When headaches interrupt a sound sleep or occur during or just after exercise, sex, coughing, or sneezing, then a primary-care physician or neurology referral is in order.
Headaches run in the family? When a patient and others in a patient's household have headaches associated with dizziness and vomiting, think carbon monoxide poisoning. A more common headache family affair is migraine. My colleague, friend, and migraine expert, Dr. Carol Foster, is a prominent Phoenix neurologist and author of "Gotta Headache?" and the soon-to-hit-the-shelves (after July 1) "Migraine, Your Questions Answered." Dr. Foster offers the following insight so that medical and dental colleagues can better coordinate the diagnosis and treatment of this complex syndrome that affects more than 28 million Americans. I asked Dr. Foster, "What is migraine?"
Migraine is a genetic disease of the hypothalamus involving serotonin neurotransmission. The exact etiology of migraine is still a bit of a mystery; however, research supports a disruption in the neurotransmitter serotonin as the main culprit. To emphasize, migraine is the disease and the headache is only a symptom.
Migraine is characterized by attacks in which people experience headaches, nausea, vomiting, and sensitivity to light, sound, and smells. Sufferers often complain of mood changes such as anxiety, depression, and irritability. They might also have difficulty concentrating and suffer from fatigue. A few migraine sufferers might experience brain symptoms such as abnormal sensations, loss of balance or movement, speech problems, and visual disturbances. These abnormal sensations called "aura" often occur before the headache and without the presence of a headache. Frequently, when an aura is not present, a misdiagnosis of tension headaches or sinus headaches is made. This may result in the use of analgesics, tranquilizers, or sinus pills that cause more headaches by changing serotonin neurotransmission, which initiates medication overuse, headaches, or rebound headaches. These drugs may aggravate anxiety disorders, depression, and other serotonin-related diseases by changing the serotonin receptor on neurons as they do with headache disorders.
Migraine is a process with fairly consistent symptoms experienced during several days. This process has been described like acts of a play: not everyone will experience all of the symptoms, and people may experience different symptoms with each migraine attack.
The first phase of a migraine attack, the Prodromal Phase or Act I, lasts 12 to 24 hours. During this time, a sufferer will experience changes in appetite, either decreased or increased. Some sufferers will experience cravings for certain foods. Hands and feet may swell, and constipation might be a problem. Mood changes are common during this phase. A sufferer might feel anxious or depressed. Difficulty concentrating is common. There might be difficulty spelling and doing simple mathematics or word-finding problems. Many sufferers will feel tired and find themselves yawning excessively.
The next phase of a migraine attack, Act II, is the Aura Phase. This phase will have transient or temporary neurological symptoms that disappear within 23 hours. The aura usually lasts 30 to 60 minutes and precedes the headache by 20 to 30 minutes. Usually, these symptoms are visual disturbances. One might experience momentary spots of color, black spots, or bright flashes of light. Others might have a change in their central vision. It might be total loss of vision or a visual distortion like looking through broken glass or a kaleidoscope. Often there will be bright silver zigzag lines surrounding the area of vision loss. The area of visual loss may expand gradually over 20 to 30 minutes. Infrequently, objects may appear to move or change shape or size. Instead of visual disturbances, some might experience a tingling sensation in the arm or around the mouth. Others might experience difficulty speaking, vertigo, or loss of balance.
The next phase, or Act III, is the Headache Phase. The headache is frequently one-sided but can be located anywhere on the head. It is typically described as a throbbing pain, however, it might be experienced as a steady or squeezing pressure, burning sensation, or sharp pain called ice-pick pain. The headache might last hours or days. Typically, the headache is of shorter duration in children.
The final phase, Act IV, is the Postdromal Phase. Many describe this as a migraine hangover. It lasts 12 to 24 hours. The most common symptoms are mood changes such as depression or euphoria, increased urination, diarrhea, and food intolerance. When migraine attacks occur frequently, many of the symptoms go unrecognized by some physicians and lead to unnecessary testing and treatment.
Understanding migraine and its treatment requires a quick review of brain physiology. The brain is capable of running millions of computer programs instantly while simultaneously sending and receiving electrical impulses. The nerves connect with one another not by touching, but by releasing certain chemicals (neurotransmitters) that cause a reaction in neighboring brain cells. Serotonin and adrenaline are two of the most important neurotransmitters in the biology of the emotional and physical stress response system, and hence, in migraine syndrome. Serotonin is the calm chemical and adrenaline is the excitatory chemical. Together, these neurotransmitters modulate brain-cell activity.
When the two neurotransmitters are balanced and function normally in the emotional part of the brain — the limbic system — and in the thought-processing part — the frontal lobe — migraine is inactive. The frontal lobe, limbic system, and dorsal raphe, the pain-control system and sleep/wake system, are located in the brain stem and are interlinked through the hypothalamus (the center of the autonomic nervous system, our body's stay-alive software.) The limbic system is linked with the hypothalamus, which causes changes in the body such as increased heart and respiratory rates, perspiration, nausea, etc., with different emotions.
As the brain is the computer, the hypothalamus is the stay-alive software regulating all of the automatic functions of the body via the autonomic nervous system. The cardiovascular, hormonal, respiratory, sleep/wake, pain-control, and immune systems are all regulated by the hypothalamus, which automatically controls blood pressure, heart rate, temperature, respiratory rate, and normal blood-glucose levels to prevent brain-cell damage. It is the body's internal clock as it regulates hormones and sleep/wake cycles and controls the body's physical reaction to emotional stress, physical stress, and pain. The hypothalamus receives large amounts of blood and is one of the few parts of the brain where substances in the blood can directly enter the brain (blood-brain barrier).
The migraine attack starts a cascade of neurological events that spread from the hypothalamus, across the cortex, and down the brainstem. The disruption of pain modulation in the trigeminal nucleus caudalis in the brainstem causes activation of the trigeminal nerve and release of neuroactive peptides in the neurovascular junction of meningeal vessels. The release of the neuroinflammatory peptides not only cause the vasodilation of the vessels and headache, but activate sensory neurons in the trigeminal nerve, which can then recruit second- and third-order sensory neurons in the brainstem. The activation of the second- and third-order sensory neurons occurs with prolonged migraine attacks and is called central sensitization. The central sensitization produces unusual sensory symptoms that are caused by cutaneous allodynia. Cutaneous allodynia is defined as pain resulting from a noninjurious stimulus, such as normal heat, cold, or pressure to skin (i.e., skin hypersensitivity). Central sensitization contributes to the transformation of migraine into chronic daily headache. The overuse of analgesics, which is thought to be conducive to the process, is the cause of medication overuse headache.
Migraine is more than a bad headache; it predisposes the patient to several chronic pain disorders that with time may overlap, making it impossible for the patient to obtain relief without a multidisciplinary approach. Medication management of migraine and other headache variants is only initiated after the patient demonstrates compliance with lifestyle changes. Headache sufferers are taught that medications such as analgesics, tranquilizers, and muscle relaxants change the serotonin receptor and inhibit the normal function of this neurotransmitter.
Comprehensive treatment emphasizing control of the disease (not the symptoms) is key. Migraine sufferers are best served if they can change their lifestyle to avoid overstimulating the autonomic nervous system. Because certain drugs, food, food additives, and anxiety deplete serotonin, headache sufferers must demonstrate compliance with dietary restrictions, daily exercise, and stress management before medications are started. They are provided educational materials and instruction about how certain food and stress deplete serotonin and how exercise, stress reduction, and spiritual reflection increase serotonin. The medication class known as triptans (Imitrex, etc.) provides acute abortive relief by acting on the serotonin system and is effective.
Patients are asked to consider serotonin neurochemistry as a credit card. Certain food and food additives waste serotonin by stimulating the release of adrenaline, so dietary changes, including a list of food and food additives to avoid, is central to treatment. They are encouraged to strictly adhere to dietary restrictions until the disease is well controlled. Only then can they cautiously add back certain food. Record-keeping and trend analysis is important as in all chronic diseases.
The key to controlling migraine is reducing the frequency of the attacks. Headaches beget headaches. A migraine attack may be triggered by a variety of events or substances, but triggers are not the cause of their headaches. Nevertheless, reducing or eliminating the triggers is a crucial part of disease management. Many migraineurs search for that one medical or dental professional who can "fix" a migraine by "fixing" the individual trigger. It is crucial that both the medical and dental community communicate and collaborate in the diagnosis and treatment of this common, complicated, chronic, neurological illness.
Anita C. Murcko, MD, FACP, is medical director of Healthcare Group of Arizona in Phoenix. E-mail her email@example.com.
Carol A. Foster, MD, lives in Phoenix with her daughters, Melissa and Jennifer. A West Virginia native, she is a 1985 graduate of Marshall University School of Medicine. A migraine sufferer herself, Dr. Foster chose neurology as a specialty and in 1989 completed a neurology residency at the Barrow Neurological Institute, which included a headache clerkship at the Princess Margaret Migraine Clinic in London. Later that year, she set up practice in Phoenix and established the Valley Neurological Headache and Research Center. True to her heritage, Dr. Foster brings a down-to-earth, no-nonsense approach to her patients and everyone she meets. She has cultivated a passion to better inform and teach patients, health care professionals, and the general public that there is more to treating headache than taking a pill. Dr. Foster is a board-certified neurologist and member of several professional organizations, including the International Headache Society, National Headache Foundation, American Headache Society, American Council for Headache Education, American Medical Association, Arizona Medical Association, and American Academy of Neurology. She is a reviewer for the medical journals Headache and Headache Quarterly. She is the author of several medical publications on headache, and two lay books. She has served and is currently serving as principal investigator for several pharmacological studies. She is a member of the speaker's bureau for AstraZeneca, GlaxoSmithKline, Merck, Ortho-McNeil, Pfizer, and UCB Pharma, all leaders in migraine drug research and development. She has given lectures and seminars on headache and has made numerous television and radio appearances. Dr. Foster is a member of the clinical teaching staff of Good Samaritan Medical Center Family Practice Residency, Midwestern University Osteopathic School of Medicine, and University of Arizona School of Medicine.