A recent study has found that prolonged auras are common and are phenotypically similar to other auras. Based on the observed duration of aura symptoms, the researchers suggest reconsidering the use of the term “prolonged aura."
There is currently a limited amount of research involving prolonged aura (PA) in migraine—having 1 or more aura symptoms lasting between 60 minutes and 7 days. However, a recent study has found that prolonged auras are common and are phenotypically similar to other auras (non-PAs).
“Worldwide migraine is the third most common disorder and around 30% of sufferers experience migraine auras. Aura comprises completely reversible visual, sensory, or language symptoms (occurring respectively in 98%, 36% and 10% of auras),” wrote the authors of the study. They added, “We present a prospective study focusing on the frequency of occurrence and characteristics of PA.”
The researchers recruited 224 patients from the Headache Centers of Pavia and Trondheim who suffered from migraine with aura between October 2012 and July 2014. Patients were followed until May 2015 and were asked to record characteristics of 3 consecutives attacks in an ad hoc aura diary, where they would describe the visual, sensory, and dysphasic aura symptoms, as well as the duration.
Of the patients, 72 recorded 3 consecutive auras, resulting in 216 recorded auras. Of these patients, 19 experienced at least 1 PA, with 9 patients experiencing 3 and 10 patients experiencing 1 or 2.
PAs and non-PAs with were compared based on 20 features. PAs were characterized by a higher frequency of non-visual symptoms. The authors observed the same results when comparing auras with a minimum of 1 symptom lasting more than 2 hours and those lasting more than 4 hours with others.
Overall, the authors noted that their findings show that, phenotypically, PAs are similar to non-PAs and are fairly common with 17% of all auras being PA and with 26% of patients experiencing at least 1.
“This can be expected when if we consider the pathophysiology of auras and recognize that aura symptoms with a longer duration are likely to be related to a cortical spreading depression proceeding across a longer path on the respective brain area,” they wrote.
The authors also note that their findings suggest the need to reconsider the use of the term “prolonged aura,” which is currently defined as more than 60 minutes and less than a week. Because aura symptoms lasted less 4 hours in 95% of the cases, having that symptoms for up to 4 hours should be considered typical, they argue. Based on this, prolonged aura would be considered aura symptoms lasting more than 4 hours.
Viana M, Sances G, Nappi G, et al. Prolonged migraine aura: insights from a prospective diary-aided study [published online August 31, 2018]. doi: https://doi.org/10.1186/s10194-018-0910-y.