Following the American Headache Society’s Scottsdale Headache Symposium in November 2018, MedPage Today posted an article which shared differing opinions from Drs. Hans-Christoph Diener and Elizabeth Loder on medication overuse headache (MOH). While Dr. Diener noted that “we can identify people with chronic migraine who are at risk to have medication overuse,” and that following successful withdrawal treatment “the majority of patients…revert to episodic migraine,” Dr. Loder pointed out that while MOH may exist and contribute to chronic migraine, “it is over-emphasized and the evidence in support of these concepts is weak.”
For this article, I’ve asked Drs. Marcelo Bigal, Rob Cowan, Jack Schim, and Stewart J. Tepper to share their perspectives on this topic. I also asked both Dr. Diener and Dr. Loder to expand on their comments. We will see Dr. Diener’s response to the article, but we did not hear back from Dr. Loder. Lastly, I will weigh in on the MOH discussion.
Marcelo Bigal, MD, PhD
Chief Medical Officer, Purdue Pharma
The issue of medication overuse headache (MOH) needs to be disentangled into a few separate but related issues. First, do excessive medications make migraine worse? Second, should MOH be considered a distinct form of headache? And how can evidence inform clinical practice?
Robust evidence supports the fact that excessive acute medication use is associated with increased headache frequency among migraineurs. In a large epidemiological study, we demonstrated that exposure (medication) precedes outcome (increased headache frequency). 1 The risk was higher for barbiturates, followed by opioids and triptans, and was not increased by nonsteroidal anti-inflammatory drugs (NSAIDs). Dose response and critical exposure levels were identified. Based on this study and several others, we argued that criteria of causality had been demonstrated beyond reasonable doubt. 2
However, since the effect is specific to migraine in that the exposure only increases the risk in migraineurs, not in individuals with other types of pain, we do not consider MOH a distinct entity. Instead, we believe that excessive medication is a risk factor for chronic migraine (CM). Therefore, we should be able to subdivide CM into 2 groups, one with and one without excessive medication use.
From a clinical perspective, physicians should monitor acute medication consumption in individuals with migraine and should be liberal in starting preventive therapy. In those with CM and excessive acute medication use we don’t advocate abrupt discontinuation of acute medications, since some preventive medications, especially the newer anti-calcitonin gene-related peptide ( CGRP) antibodies, seem to work equally well in individuals with and without excessive use of medication, 3 allowing more natural and gradual control of acute medication consumption without the need for detoxification.
Rob Cowan, MD, FAAN, FAHS
Higgins Professor of Neurology and Neurosciences
Chief, Division of Headache Medicine, Dept. of Neurology and Neurosciences
Director, Stanford University School of Medicine
As is often the case when 2 smart people take artificially imposed opposite positions, the truth will lie somewhere in the middle. I doubt either of the debaters would argue either extreme position: MOH does not exist, or MOH when present is solely responsible for chronic daily headache (CDH). The argument that the absence of controlled studies negates the proposition fails the common-sense test: Without a controlled study, we can’t be sure that wearing a helmet when bicycling is better than not. In such a case, observational data is sufficient. Could there be confounders (eg, helmet wearers are more inclined to ride safely)? Of course, but is that important? Similarly, does the fact that some MOH patients continue with CDH after cessation of medication overuse warrant a general de-emphasis? Certainly not for the third-to-half of patients who benefit from limiting medication use.