Refractory Chronic Migraine
Refractory Chronic Migraine (RCM) results in a great deal of disability for patients and has a huge impact on their quality of life. In order to provide a framework for other physicians and health care providers, this author initiated the Refractory Headache Special Interest Section of the American Headache Society. This committee of headache specialists seeks to define a standard of diagnosis for health practitioners and raise awareness of improved treatments for headache. Since its inception, the committee has primarily focused on the critical area of RCM definition. Chronic migraine (CM) is outlined in Table 1. Chronic migraine occurs in approximately 2% of the population; we do not yet know the epidemiology or rate of occurrence of RCM. The current pro-posed criteria for RCM are summarized in Table 2.1,2
|A.||Headache (tension-type and/or migraine) on 15 days per month for at least 3 months|
|B.||Occurring in a patient who has had at least 5 attacks fulfilling criteria for
1.1 Migraine without aura
On 8 days per month for at least 3 months, headache has fulfilled C1 and/or C2 below, that is, has fulfilled criteria for pain and associated symptoms of migraine without aura
|1.||Has at least two of ‘a’ through ‘d’|
|c)||Moderate or severe pain intensity|
|d)||Aggravation by or causing avoidance of routine physical activity
(e.g. walking or climbing stairs)
And at least one of ‘e’ or ‘f’
|e)||Nausea and/or vomiting|
|f)||Photophobia and phonophobia
|2.||Treated and relieved by triptan(s) or ergot before the
expected development of C1 above
|D.||No medication overuse and not attributed to another causative disorder.
The definition of RCM is a work in progress; the final version may be quite different than that cited in Table 2. We may want to add modifiers as to the degree of refractoriness (mild, moderate or severe). In some patients, RCM improves or resolves over time, while others worsen. These situations need to be addressed in the definition.3
Challenges of Refractory Migraine3
There are a number of major challenges in dealing with RCM with each category requiring a different approach. These include:
- 1) What does the role of disability play, and should disability help to define RCM?
- 2) How resistant to the myriad of treatments does one have to be?
- 3) There is no accepted, identifiable biological marker for RCM.
- 4) The degree of refractoriness can change over time, improving or worsening. What role does this varying severity play?
- 5) There are various subsets of RCM— post-traumatic headache, RCM with or without Medication Overuse Headache (MOH), with or without major psychiatric comorbidities, etc.
We are just beginning to look beneath the surface as to what causes RCM. Some of the issues are:
- 1) What is the role of genetics in drug resistance and inheritance of chronic headaches?
- 2) What structural changes (in white matter or iron deposition) play a role?
- 3) What part does central sensitization and plasticity have?
- 4) How much involvement is peripheral vs. brainstem vs. cortical?
- 5) How does MOH affect the structure and function of the nervous system?
- 6) What is the physiologic impact of psychiatric comorbidities? Do de-pression and/or anxiety fuel the headaches?
Continuing research is critical in order to answer these questions. We do know several risk factors that may drive the development of RCM. These include lifestyle issues such as medication overuse, sleep habits, caffeine overuse and obesity.5 While pharmacotherapy may be the cornerstone of treatment, other modalities are no less important. The patient must manage his or her triggers with regards to sleep, food and caffeine. Exercise and weight reduction are encouraged. Stress, another major trigger, may be relieved by practicing biofeedback and/or yoga. Depending on the origin of the pain, physical therapy and massage may help. Problems with the teeth, jaw, eyes or neck should be addressed.
Medication Overuse Headache
Table 1, Part D, refers to the overriding condition of MOH. MOH is a critical issue that must be addressed early in the treatment of any form of headache.6 Abortive medication overuse is a major risk factor for the progression of migraine into RCM. Some patients have medication overuse without an increase in headache. In others, overuse of abortives is the principal cause for the headaches. The criteria for MOH are listed in Table 3. Note that the headache progresses instead of subsides over time, and the calls for prescription refills will become more frequent with the progression. When treating patients with MOH, the offending drugs will need to be withdrawn or limited. While we do not know with any certainty the percentage of RCM patients where MOH is a major contributor, we do know that MOH should be one of the first considerations when a patient presents with worsening headaches.
Significant abuse in childhood, whether sexual, physical or emotional, may predispose one to develop RCM, separately or in conjunction with other central sensitization syndromes such as fibromyalgia, irritable bowel syndrome, chronic pelvis pain or TMD. Important comorbidities include anxiety, depression, the bipolar spectrum, personality disorders, somatization and post-traumatic stress disorder.7 The author has published several articles on the bipolar spectrum and personality disorders and how they relate to migraine patients; a brief synopsis will be discussed here.