This article requires a subscription to view the full text. If you have a subscription you may use the login form below to view the article. Access to this article can also be purchased.
Abstract
Background: Chronic migraine (CM) is characterized by 15 or more migraine days per month. Most adults with chronic daily headache (CDH) that evolved from migraine have <15 days of migraine/month. They are often classified as transformed migraine (TM), a disorder not addressed in the International Headache Society classification.
Objective: To test the hypothesis that early in the course of migraine chronification, the frequency of migraine attacks is high and that as illness progresses the frequency of nonmigraine headaches increases.
Methods: Information was collected on 402 adults with TM and was divided into two groups. Group 1 TM had ≥15 days of migraine/month, whereas Group 2 TM had <15 days of migraine/month. Risk factors were modeled for number of migraine days per month using logistic regression.
Results: Of 402 subjects with TM, 121 (30.1%) were in Group 1. The proportion of Group 1 subjects decreased with age, from 71% below age 30 to 22% age 60 or above. The correspondent proportion of Group 2 increased from 29 to 78%. More than 15 days of migraine per month was independently predicted by younger ages (<40 years; p = 0.002), shorter interval from episodic to CDH (<5 years; p = 0.003), and shorter time since the development of CDH (<6 years; p < 0.0001).
Conclusion: Chronic migraine is an earlier stage of transformed migraine.
AAN Members
We have changed the login procedure to improve access between AAN.com and the Neurology journals. If you are experiencing issues, please log out of AAN.com and clear history and cookies. (For instructions by browser, please click the instruction pages below). After clearing, choose preferred Journal and select login for AAN Members. You will be redirected to a login page where you can log in with your AAN ID number and password. When you are returned to the Journal, your name should appear at the top right of the page.
AAN Non-Member Subscribers
Purchase access
Letters: Rapid online correspondence
REQUIREMENTS
You must ensure that your Disclosures have been updated within the previous six months. Please go to our Submission Site to add or update your Disclosure information.
Your co-authors must send a completed Publishing Agreement Form to Neurology Staff (not necessary for the lead/corresponding author as the form below will suffice) before you upload your comment.
If you are responding to a comment that was written about an article you originally authored:
You (and co-authors) do not need to fill out forms or check disclosures as author forms are still valid
and apply to letter.
Submission specifications:
- Submissions must be < 200 words with < 5 references. Reference 1 must be the article on which you are commenting.
- Submissions should not have more than 5 authors. (Exception: original author replies can include all original authors of the article)
- Submit only on articles published within 6 months of issue date.
- Do not be redundant. Read any comments already posted on the article prior to submission.
- Submitted comments are subject to editing and editor review prior to posting.
