What are the other Names for this Condition? (Also known as/Synonyms)

• CM (Chronic Migraine)

What is Chronic Migraine? (Definition/Background Information)

• Migraine headache is a longstanding neurological disorder and the most common form of headache that is characterized by severe pounding and pain on one side of the head, which can last for several hours
• According to the International Classification of Headache Disorders, Chronic Migraine (CM) is defined as a headache observed on at least 15 days per month for a minimum period of 3 consecutive months. Additionally, at least 5 attacks/month have to be reported and the characteristics of migraine headache with/without aura must be noted on at least 8 days each month
• Therefore, in order for a physician to diagnose Chronic Migraine, the maintenance of a daily headache dairy is important with information on pain intensity and other associated symptoms of the headache, recorded daily for the said period
• A clear differentiation should be established between Chronic Migraine and various other similar headache conditions and their subtypes, such as tension-type headaches, new daily persistent headaches, and medication-overuse headaches (MOHs). In many cases, MOH or rebound headache is commonly misdiagnosed as Chronic Migraine
• The development of Chronic Migraine from episodic migraine may depend on several factors including drug and medication abuse, mental stress, physical exertion, insomnia, obesity, and conditions causing chronic pain. Thus, controlling these factors may help in delaying or even preventing the onset of Chronic Migraine
• Even though there are medications, non-traditional therapies, and home remedies for treating Chronic Migraines, the prognosis of the condition is based on several factors. Chronic Migraines are long duration conditions that can be severely disabling for some individuals

Who gets Chronic Migraine? (Age and Sex Distribution)

• According to the American Migraine Foundation, up to 1% of the global population may be affected by Chronic Migraine
• Migraines are common in individuals of all age groups; although, adolescents and young adults are affected more commonly than older adults. Adults over the age of 50 years show fewer cases of migraine
• Women are more commonly affected than men by Chronic Migraines
• The condition is seen worldwide; there is no particular preference for any race or ethnicity

What are the Risk Factors for Chronic Migraine? (Predisposing Factors)

The American Migraine Foundation reports that ever year about 1 in 40 individuals with episodic migrainous condition tend to move to a chronic migrainous state. Thus, individuals with longstanding migraine headaches that are generally not responsive to therapy have a very high risk for Chronic Migraines.

The transition of episodic migraines to Chronic Migraines are further aided by certain factors and conditions such as the following:

• Anxiety and depression
• Asthma
• Being overweight or obese
• Excess caffeine intake
• Frequently feeling nauseous
• Medication abuse
• Physical and mental stressors
• Snoring
• The presence of any other pain disorder/condition
• Trauma to the head and/or neck region
• Hormonal changes: Women are more prone to Chronic Migraines due to factors and events such as menstruation, pregnancy, use of birth-control pills, and menopause

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases one’s chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Chronic Migraine? (Etiology)

The exact cause of migraine headache is not clearly established. Chronic Migraine develops from episodic migraine headaches over an extended period of time, sometimes aggravated by factors such as depression, stressful events, excess use of medication, and other underlying chronic pain conditions.

Some of the likely causes for migraines include:

• Dilatation of blood vessels in the brain
• Release of certain chemicals
• Presence of an excess amount of dopamine and serotonin; an unusual sensitivity of the blood vessels to dopamine and serotonin is noted

What are the Signs and Symptoms of Chronic Migraine?

The signs and symptoms of Chronic Migraine and migraine headache are generally the same; however, in order for longstanding migraines to be classified as Chronic Migraines, the following factors must be established:

• The headaches should be present for 15 or more days each month
• Of these, migraine-type headaches should be present for 8 or more days each month
• The minimum period under consideration should be 3 months
• The migraine may be with aura or without aura; however, at least 5 attacks must be noted

Even though the signs and symptoms may vary from one individual to another, generally five stages may be identified in the process of development of migraine headaches and these include:

1^st stage - Prodrome

The signs and symptoms exhibited during this early stage may include:

• Changes in mood that may be characterized by
  • Irritability
  • Depression
  • Uncontrollable yawning
  • Food craving
• Change in sensations 
  • Funny taste
  • Different smell
• Fatigue
• Muscle tension

2^nd stage - Aura: Aura may not be observed with all migraine headaches.

The signs and symptoms exhibited during this stage may include:

• Visual symptoms such as seeing various shapes, bright spots, or flashes of light
• Vision loss
• Pins and needles sensation in the arms or legs
• Speech defects

3^rd stage - Headache:

• Pain on one side of the head
• Experience of throbbing and severe pain
• Nausea and vomiting
• Photophobia or increased sensitivity to light
• Phonophobia or increased sensitivity to sound
• Pain that may last from 4 hours to 72 hours

4^th stage - Headache termination: The pain will subside with proper sleep and rest, even if no treatment is given.

5^th stage - Postdrome:

The signs and symptoms exhibited during this stage may include:

• Difficulty in eating
• Difficulty in concentrating
• Weakness and lethargy

How is Chronic Migraine Diagnosed?

Besides the diagnostic criteria (mentioned earlier), a diagnosis of Chronic Migraine may involve the following tests and exams:

• Complete physical examination and assessment of signs and symptoms
• Thorough analysis of personal and family medical history of migraine headaches
• Neurological examination by a qualified healthcare provider, if necessary
• Laboratory tests may be performed to rule out other causes for pain
• Computerized tomography (CT) scan of the head
• Magnetic resonance imaging (MRI) scan of the brain

It is also important to exclude all forms of secondary headaches, meaning those that arise from other underlying conditions, prior to establishing a diagnosis of Chronic Migraine. These include chronic headaches arising from:

• Overuse of medications
• Use of illegal substances
• Physical exertion
• Head injuries
• Tumors and lesions in the brain
• Any vascular disorder; high blood pressure
• Any genetic condition
• Infections
• Any cold stimulus

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Chronic Migraine?

Chronic Migraine may lead to complications such as:

• Abdominal signs and symptoms: Pain in the abdomen, bleeding, and ulcers may be caused due to the intake of large dose of pain-relieving medications
• Serotonin syndrome that may be caused by the intake of certain antimigraine medications
• Severe emotional and mental stress; depression
• Poor performance at school or at work
• Overall, severely affected quality of life
• Secondary headaches due to medication
• Low risk for brain stroke against a background of migraine attack
• Side effects of medication including nausea and vomiting

How is Chronic Migraine Treated?

The following medications may be used in the treatment of Chronic Migraine:

• Pain-relieving medicines such as:
  • Ibuprofen and acetaminophen
  • Combination medication of acetaminophen, aspirin, and caffeine
  • Triptans and ergotamines
  • Anti-nausea medications
  • Opiates, for severe pain
• Preventive medications such as:
  • Antidepressants
  • Cardiovascular drugs including blood pressure medication
  • Anti-seizure drugs
  • Botulinum toxin type A (Botox): This is reportedly effective in preventing Chronic Migraines

Some of the non-traditional therapies that are used in treating Chronic Migraine include:

• Acupuncture
• Biofeedback (relaxation technique)
• Manual therapy involving massage and chiropractic treatments
• Use of vitamin and mineral supplements

Certain home care treatments may include:

• Muscle relaxation exercises including meditation, yoga, listening to music, and gardening
• Getting adequate sleep; while sleeping, resting in a dark quiet room
• Applying ice packs
• Addressing the risk factors appropriately can delay onset of Chronic Migraine

How can Chronic Migraine be Prevented?

The prevention of Chronic Migraine largely depends on controlling or avoiding certain risk factors and by bringing about some lifestyle changes. These may include:

• Eating healthy, staying well-hydrated, and exercising regularly; addressing factors that tend to increase stress
• Keeping a diary to record the headache episodes on a regular basis; also, a record of any other associated symptoms that may occur with the headaches
• Avoiding triggers of migraine headaches
• Reducing the effects of estrogen (for some women)
• Having a stress-free routine with regular sleeping habits
• Strictly follow drug label instructions on usage and dose
• Always avoid self-medication and self-adjustment of medication dose
• Check with the healthcare provider about consumption of caffeine-based beverages, if the prescribed medication contains caffeine

Periodic monitoring and follow-up of any longstanding migraine condition with the healthcare provider is recommended.

What is the Prognosis of Chronic Migraine? (Outcomes/Resolutions)

• The long term outlook of Chronic Migraine varies from one individual to another and depends on several factors
• However, in general, Chronic Migraines can be severely disabling and depressing for many individuals

Additional and Relevant Useful Information for Chronic Migraine:

The following DoveMed website link is a useful resource for additional information:

https://www.dovemed.com/health-topics/neurological-institute/