Pain Medicine 2015; 16: 1246 Wiley Periodicals, Inc.
EDITORIAL Are Chronic and Episodic Migraine Distinct Neurophysiological Entities? More Research is Needed Dr. Spierings and his coauthor have conducted a clinicalbased survey regarding women with chronic and episodic migraine and assessed the presence of common menstrual and endocrinological disorders in each group. The topic is an important one. Unfortunately, the study, by the authors’ own acknowledgement, has several limitations, not the least of which include its retrospective design, relatively small sample size, nonvalidated questionnaire, and more. A clinic-based study is dependent on survey participation and therefore an intrinsic bias exists. Among the nonmenstrual disorders discussed, the authors’ consider hypothyroidism. The authors’ addressed this disorder because it has been associated with both chronic migraine and menstrual disorders. The editors of the Journal determined ultimately, despite its limitations, that the report was worthy of publication because it brought attention to an important, generally overlooked possibility: that differences between episodic and chronic migraine may not be principally confined to the number of headache days per month, but instead reflect a more profound pathophysiological distinction that involves the association in chronic migraine (more than in its episodic form) with significant comorbid illness. In a section titled “clinical implication,” the authors address this issue suggesting that chronic migraine
This article was published online on June 5, 2015. The title has been updated since the first online publication date. This notice is included in the online and print versions to indicate that both have been corrected.
1246
patients may be more affected than their episodic counter parts by comorbid illness that “span the entire gamut of body systems: neurological, psychiatric, musculoskeleton, cardiovascular, respiratory, gastrointestinal, genitourinary, endocrine, and immunological.” Such a sweeping statement seems unsupported by the data established in this paper except for that possibly associated with endocrinological disorders. The editors fully acknowledge significant limitations in this report, as do the authors, but the manuscript nonetheless provides the opportunity to raise an issue that has heretofore been infrequently addressed. Chronic migraine and episodic migraine may be distinct entities separated not simply by the frequency of headache events and days, but by more fundamental neurophysiological distinctions. This study does not establish that these distinctions exist but provides the basis for further discussion and research.
JOEL R. SAPER, MD, FAAN Founder & Director of MHNI Clinical Professor of Neurology Ann Arbor, Michigan, USA
EDITORIAL Are Chronic and Episodic Migraine Distinct Neurophysiological Entities? More Research is Needed Dr. Spierings and his coauthor have conducted a clinicalbased survey regarding women with chronic and episodic migraine and assessed the presence of common menstrual and endocrinological disorders in each group. The topic is an important one. Unfortunately, the study, by the authors’ own acknowledgement, has several limitations, not the least of which include its retrospective design, relatively small sample size, nonvalidated questionnaire, and more. A clinic-based study is dependent on survey participation and therefore an intrinsic bias exists. Among the nonmenstrual disorders discussed, the authors’ consider hypothyroidism. The authors’ addressed this disorder because it has been associated with both chronic migraine and menstrual disorders. The editors of the Journal determined ultimately, despite its limitations, that the report was worthy of publication because it brought attention to an important, generally overlooked possibility: that differences between episodic and chronic migraine may not be principally confined to the number of headache days per month, but instead reflect a more profound pathophysiological distinction that involves the association in chronic migraine (more than in its episodic form) with significant comorbid illness. In a section titled “clinical implication,” the authors address this issue suggesting that chronic migraine
This article was published online on June 5, 2015. The title has been updated since the first online publication date. This notice is included in the online and print versions to indicate that both have been corrected.
1246
patients may be more affected than their episodic counter parts by comorbid illness that “span the entire gamut of body systems: neurological, psychiatric, musculoskeleton, cardiovascular, respiratory, gastrointestinal, genitourinary, endocrine, and immunological.” Such a sweeping statement seems unsupported by the data established in this paper except for that possibly associated with endocrinological disorders. The editors fully acknowledge significant limitations in this report, as do the authors, but the manuscript nonetheless provides the opportunity to raise an issue that has heretofore been infrequently addressed. Chronic migraine and episodic migraine may be distinct entities separated not simply by the frequency of headache events and days, but by more fundamental neurophysiological distinctions. This study does not establish that these distinctions exist but provides the basis for further discussion and research.
JOEL R. SAPER, MD, FAAN Founder & Director of MHNI Clinical Professor of Neurology Ann Arbor, Michigan, USA
