Researchers Measure Complex Migraine Aura Duration, Recommend Disorder Category Change

Though the third edition of the International Classification of Headache Disorders (ICHD-III) proposes to label aura in non-hemiplegic migraine that lasts longer than one hour but shorter than one week as probable migraine with aura — or probable complex migraine — a group of researchers from Italy, Switzerland, Germany, and California decided to analyze clinical studies to determine whether or not that timeframe aligns with the typical duration of migraine aura.

For their systematic review, published in the May 2013 issue of the International Headache Society’s Cephalalgia journal, Michele Viana of the Headache Science Centre in the C. Mondino National Institute of Neurology Foundation at IRCCS, in Italy, and co-authors “performed a comprehensive literature search in order to identify all population-based studies or case series in which clinical features of non-hemiplegic migraine with aura (NHMA) — including but not restricted to aura duration — were reported, in order to gain a complete coverage of the available scientific data on aura duration.”

The researchers ultimately found 10 articles that measured aura duration, five studies that recorded patients whose NHMA lasted more than an hour, and six articles that reported the timeframe of single NHMA symptoms. After reviewing the second set of literature, the authors discovered between 12 percent and 37 percent of the study subjects experienced NHMA symptoms lasting more than one hour. After examining the third set, the authors found more than one hour durations for visual aura disturbances in 6 percent to 10 percent of patients, sensory aura in 14 percent to 27 percent of patients, and aphasic aura in 17 percent to 60 percent of patients.

At the conclusion of their systematic review, the authors write “the data indicate the duration of NHMA may be longer than one hour in a significant proportion of migraineurs,” especially those with non-visual aura symptoms. Thus, the researchers recommend “reinstating the category of prolonged aura for patients with symptoms longer than an hour and less than one week,” as they note “the term ‘probable’ seems inappropriate in ICHD-III.”

In “ICHD-3: What Changes Do We Need Regarding Migraine?” from the June 2011 issue of Current Pain and Headache Reports, Gian Camillo Manzoni of the Headache Center at the University of Parma, in Italy, writes that ICHD-III will “provide a framework to systematize those migraine forms that (ICHD-II) included in its Appendix.” The beta version of ICHD-III is scheduled to be published sometime this year, though an exact release date has not yet been made public by the International Headache Society.