What Is Chronic Migraine?

Do you suffer from a headache every other day? If this is the case, it could suggest you may be suffering from a condition called chronic migraine. Chronic migraine is a stubborn condition that is hard to manage. It affects between 1 and 2.2% of the overall population worldwide, with females being more affected than males.¹

Chronic migraine is a common headache disorder characterised by having more than 15 days per month when you experience headache, where at least 8 of these headache days have migraine features:

• The pain is often intense at a moderate or severe level
• The pain is on both sides or one side of the head
• The head pain causes a pounding, throbbing or pulsating sensation
• The pain becomes worse with physical activity or movement
• You experience nausea, vomiting, and/or light and sound sensitivity, along with the head pain

The other 7 headache days don't need to be full migraine attacks. For example, if you have a migraine attack with a severe headache one day and the next day you have a low-severity headache, this would be one day of migraine headache and one day of ‘other’ headache. 

This article will explain and give an overview of the causes, symptoms and treatment for chronic migraine and, hopefully, provide answers to key questions regarding the condition.

Overview

Headaches can be divided into two categories: chronic and episodic. Chronic migraine is defined as headaches that occur more than 15 days per month for longer than 3 months.

On the other hand, episodic migraine typically occurs only a few times a year.

Chronic migraine is a severely disabling condition that is difficult to manage. This is due to chronic migraine patients experiencing substantially more frequent headaches, with less pain-free intervals, than those with episodic migraine. Chronic migraines tend to begin as episodic migraines but then develop into a more frequent headache pattern.² 

Causes of chronic migraine

It is not fully understood what causes chronic migraine, although it is thought that migraines are a result of temporary changes in the chemicals, nerves, and blood vessels in the brain. According to researcher Dodick, genetic and biological factors influence neural networks in the brain to cause chronic migraine.³

Medication overuse headache is a type of chronic daily headache (CDH) where the patient suffers headaches as a result of frequent use of acute medicines or painkillers, such as ergotamines, triptans, opiates, non-steroidal anti-inflammatory drugs (NSAIDs) and paracetamol. Medication may start to be overused if another dose is taken as the previous effect begins to wear off and pain returns. The need to treat returning pain results in the further use of painkillers, which eventually become ineffective in the management of pain.

Chronic migraine also has some common risk factors associated with it:

• Mood disorders, in particular, depression and anxiety 
• Other pain disorders
• Obesity
• Asthma
• Snoring
• Stressful life events (severe emotional or physical trauma)
• Head/neck injury
• Excessive caffeine intake
• Acute medication overuse
• Persistent, frequent nausea
• Disrupted sleeping pattern

Migraines that cannot be managed by medication can transform into a chronic daily headache or chronic migraine. Transformed migraines are difficult to treat and so implementing preventive treatment as early on in life as possible is very important. 

Signs and symptoms of chronic migraine

There are different types of migraine, including:

Migraine with aura - this is where there are specific warning symptoms just before the migraine begins. These typically present as disturbances in the visual field but may also cause other abnormalities. Each symptom tends to begin gradually, building up over several minutes, and can last up to 1 hour. 

Examples of warning symptoms that occur in migraines with aura include::

• Seeing flashing lights, bright spots or various shapes
• Pins and needles sensation in limbs
• Loss of vision
• Difficulty speaking
• Numbness or weakness in the face or on one side of the body

Migraine without aura - this is the most common type of migraine, where the onset of the headache occurs without any specific warning signs. 

Migraine aura without headache - also known as silent migraine, this is where you experience symptoms associated with a migraine aura, but a headache does not develop.

Symptoms of chronic migraine are the same as episodic migraines, and the only difference is the frequency of the headaches. It is suggested that a migraine episode progresses in four stages: prodrome, aura, attack and post-drome. However, not everyone who suffers from chronic migraine goes through all these stages.The typical symptoms to look out for include:

• Moderate to severe head pain, worsened by physical activity
• Pain on one or both sides of the head
• Pounding, throbbing, or pressure-like pain
• Sensitivity to light, sound, smells
• Nausea/vomiting
• Dizziness

Management and treatment for chronic migraine

A treatment plan can consist of acute medication, preventive medication as well as non-medication preventive treatments, such as biofeedback and cognitive behavioural therapy. 

Acute Medicines

Acute medicines for chronic migraine are taken to relieve the symptoms of a migraine attack. They are to be taken once the attack has begun and should be fast-acting. 

The types of acute medication that are recommended for the treatment of chronic migraine pain fall under three different categories:

• Simple analgesics are medications that treat the pain experienced during a migraine attack, ncluding paracetamol and non-steroidal anti-inflammatory drugs (NSAIDs), like ibuprofen. These types of painkillers are favoured over those that contain opioids, as the latter can be addictive
• Anti-emetics, also known as ‘anti-sickness’ medication, treat the nauseous feeling felt by some of those suffering from chronic migraine. Anti-emetics should be taken before or at the same time as an analgesicto improve the absorption of the painkillers. Examples of anti-emetics are domperidone and metoclopramide
• Triptans treat the pain and sickness associated with migraine attacks. There are multiple triptans available in different formulations and delivery systems, such as nasal sprays or tablets, that you can take depending on what best suits you. Triptans are considered very safe but people who have coronary heart disease (CHD), peripheral vascular disease, cerebrovascular disease, uncontrolled high blood pressure, and acute vascular conditions should not take them.

Preventive Medicines

Prophylactic treatment or preventive medicines are used to prevent migraine attacks. There are seven different categories of preventive medicines that can be used for the treatment of chronic migraine, most of which have been repurposed from other conditions:

• Angiotensin II blockers
• Anti-convulsants
• Beta-blockers
• Calcitonin Gene-Related Peptide pathway monoclonal antibodies
• Tricyclic antidepressants
• Calcium channel blockers
• Anti-serotonergic drugs 

Injections

• Botox injections are approved by the National Health Service (NHS) for the treatment of chronic migraine in the UK. Botox, also known as botulinum toxin type A, is a nerve toxin that paralyses muscles. It was discovered to help with chronic migraines when affected individuals who received Botox as a cosmetic procedure realised that they were also experiencing fewer headaches after the injections
• A Greater Occipital Nerve (GON) block is an injection containing a small dose of local anaesthetic and/or steroid. The greater occipital nerves that travel up the sides of the back of the head tend to be oversensitive in people who often have headaches. Hence, targeting this nerve helps to relieve the pain of chronic migraines

There are also a variety of dietary supplements that are claimed to be helpful for migraine and headaches, including vitamins, minerals, herbs, amino acids, and biological substances, such as enzymes. However, evidence supporting their efficacy is limited.

Each of the different treatment options mentioned in this article have their own related side effects. Treatments should be thoroughly discussed with and recommended to you by your healthcare provider. 

FAQs

How is chronic migraine diagnosed?

A neurologist will take your medical history,  asking you about your pattern of migraine pain and what the pain feels like, accompanying symptoms, and any previously tried treatments. The doctor will also want to know if you suffer from any other health problems. If you experience frequent headaches (15 days a month) and present with migraine features, the neurologist would be able to diagnose you with chronic migraine.

How can I prevent chronic migraine?

Keeping a note of when you experience headaches can help prevent chronic migraine. If you notice an increase in the frequency of your headaches, see a neurologist. Not seeking treatment before your headaches become a daily occurrence can cause chronic migraine to develop, making the headaches harder to treat.

Who is at risk of chronic migraine?

The people who are most at risk of developing chronic migraine include those who:

• overuse of acute migraine medication
• have received ineffective headache treatment
• are obese
• suffer from depression
• have experienced stressful life events. 

Moreover, people who are assigned female at birth and those who have a low educational status have been associated with an increased risk of developing chronic migraine.⁴

How common is chronic migraine?

Approximately 3%of people who have episodic migraine develop chronic migraine each year. It is estimated that up to 148 million people in the world live with chronic migraine.

When should I see a doctor?

You should consult your doctor if:

• You usually have two or more headaches a week
• You often take painkillers for your headaches
• You need more than the recommended dose of over-the-counter pain remedies to relieve your headaches
• Your headache pattern changes, or your headaches worsen
• Your headaches are disabling 

Summary

Chronic migraine is a common yet disabling headache disorder. The cause is yet to be fully understood by scientists, but there are known risk factors associated with it. Some of the main contributing factors to chronic migraine include depression, obesity, and the overuse of acute medication.

Chronic migraine attacks are painful, so frequent painkiller use is common and can lead to a cycle of overuse. Therefore, to prevent chronic migraine, prophylactic treatment can be helpful.

If you experience a change in headache pattern or an increase in headache days per month, you should contact your healthcare provider or a neurologist.