Migraine Frequency: Episodic vs Chronic Migraine

Migraine is a relatively common but disabling headache disorder. Women are 2 to 3 times more likely to be living with migraine than men. One study found that migraine is one of the most common causes of disability worldwide.¹

Everyone experiences migraine slightly differently. And one person may even experience multiple kinds of migraine throughout their life. Migraine can be categorized by:²

• Their frequency
• The presence or absence of an aura
• Where on your head you experience the pain

In this article, we will discuss the frequency of migraine.

What is episodic migraine?

Episodic migraine is traditionally defined as fewer than 15 headache days per month. This definition was originally created so migraine could be more easily compared with tension headaches. However, a 2021 study looked at migraine frequency and its connection to quality of life. In this study, the researchers divided participants into 4 groups by how many headache days they had per month:³

• 0 to 7 days
• 8 to 14 days
• 15 to 23 days
• 24 or more days

Fewer than 8 headache days per month was shown to have a significantly smaller effect on quality of life.³

What is chronic migraine?

Chronic migraine is defined as having 15 or more headache days per month for more than 3 months, where at least 8 of those headache days have migraine features.³

These migraine categories exist so doctors can better understand and treat the headache symptoms that people experience. But the researchers who conducted the 2021 study thought that the current migraine categories might not be accurate. They found that people who had 8 to 14 headache days per month and those who had 15 to 23 headache days per month had similar effects on their quality of life. In the current system, these people would be split between the episodic and chronic migraine categories. The researchers hope to complete more research to understand if these categories need to change.³

They also found that those who lived with headaches for more than 24 days per month were severely affected by those headaches. They affected quality of life and their ability to hold down a job. The study concluded that more research was necessary to find more effective treatments for this group.³

What is chronification or transformation?

If you are living with migraine, you may find that your migraine may always be very similar, or they may feel a bit different every time. You may also find that the frequency of your migraine changes. Some people may transition from having episodic to chronic migraine. This process is called “chronification” or “transformation.”²

You may be more likely to experience chronification if you:²

• Have other pain disorders
• Are female
• Have a history of head or neck injury
• Are experiencing stressful life events
• Frequently use medicine to stop your migraine
• Have other disorders such as depression, snoring, sleep issues, or asthma

The good news is that those living with chronic migraine may also transition back to having episodic migraine. This can happen in anywhere from 26 to 70 percent of people living with migraine.²

What does this mean?

Unfortunately, people living with chronic migraine are more likely to experience anxiety and depression. They also are more likely to experience a lower quality of life than people living with episodic migraine. If you are having problems with your mood or mental health – regardless of how frequently your migraine attacks occur – reach out for help. You are not alone and there are resources to help you.³

Your doctor may ask you to keep a migraine journal where you record your symptoms daily for a month or more. This can help your doctor understand what migraine attacks are like for you. If you have any questions about your experience living with migraine, talk to your doctor.⁴