Some patients fail on preventives, but abortive usually work well. Others do reasonably well on preventives but continue to have severe, prolonged migraines where nothing is helpful.
There are many challenges in defining refractory headaches (as there are with depression, or epilepsy). These include:
1. Should we separate refractory to abortives from refractory to preventives?
2. Length of use: patients with 1 year of severe headaches should be viewed differently than those with 30 years.
3. The role of disability.
4. Psychiatric comorbidities (anxiety, depression, bipolar, post-traumatic stress disorder, personality disorders, and a history of childhood abuse).
5. Medical comorbidities that may be related to chronic headache (possible central sensitization syndromes), such as fibromyalgia, irritable bowel syndrome (IBS), interstitial cystitis, and TMD, and also chronic fatigue): what role should they play in assessment?
6. The role of medication overuse.
7. Pathophysiology: the role of white matter changes, iron deposition, etc.
8. Genetics and family history: how important are these?
9. Refractoriness may evolve and change over time.
There are subsets of refractory patients, by age and by headache type. Adolescents with difficult headaches are approached differently than adults. Refractory headaches in patients over age 70 present unique challenges. The varying types of headaches should be separated, with chronic migraine being the most common. Other types include refractory trigeminal autonomic cephalgia’s, post-traumatic, and chronic tension-type headache. These subsets cannot all be lumped under refractory headache.
These patients often have myriad problems. The psychiatric comorbidities play a major role in determining treatment approach. Associated medical conditions complicated therapy. The number of years of headache is important, as is the presence of disability. Medication overuse needs to be addressed. These associated conditions should be a part of any proposed “refractory grading system”.
For both treatment and study purposes, it is helpful to determine the level of refractoriness. The following is an outline of a point system that I have been using.
1. Refractory to preventives: 2 points
2. Refractory to abortives: 2 points
3. Ten or more years of chronic headache: 1 point
4. Headache almost all day, 25 or more days per month: 1 point
5. Significant psychiatric comorbidities: 1 point
6. Certain medical comorbidities (fibromyalgia, IBS, interstitial cystitis, TMD, chronic fatigue): 1 point
7. Full disability or very low functioning: 1 point
8. Moderate or severe medication overuse: 1 point
There are 10 possible points; the lowest score would be someone who is refractory to preventives or abortives (2 points), and nothing else. An individual patient’s rating may change over time, and this may be tracked over several years. For study purposes, patients with a score of 10 will lead to worse outcomes than patients with a lower rating. Tertiary clinics are filled with patients with a grade of 8 through 10, while the average physician sees only a few.
Defining and grading refractory headache has proven to be exceedingly complex.