Background: According to ICHD-II, and as proposed for ICHD-III, non-hemiplegic migraine aura (NHMA) symptoms last between five and 60 minutes whereas hemiplegic migraine aura can be longer. In ICHD-III it is proposed to label aura longer than an hour and less than a week as probable migraine with aura. We tested whether this was appropriate based on the available literature.
Methods: We performed a systematic literature search identifying articles pertaining to a typical or prolonged duration of NHMA. We also performed a comprehensive literature search in order to identify all population-based studies or case series in which clinical features of 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.
Results: We did not find any article exclusively focusing on the prevalence of a prolonged aura or more generally on typical NHMA duration. We found 10 articles that investigated NHMA features, including the aura duration. Five articles recorded the proportion of patients in whom whole NHMA lasted for more than one hour, which was the case in 12%-37% of patients. Six articles reported some information on the duration of single NHMA symptoms: visual aura disturbances lasting for more than one hour occurred in 6%-10% of patients, sensory aura in 14%-27% of patients and aphasic aura in 17%-60% of patients.
Conclusions: The data indicate the duration of NHMA may be longer than one hour in a significant proportion of migraineurs. This seems to be especially true for non-visual aura symptoms. The term probable seems inappropriate in ICHD-III so we propose reinstating the category of prolonged aura for patients with symptoms longer than an hour and less than one week.