Migraine with and without aura-two distinct entities? A narrative review

Migraine is a primary headache disorder, with a prevalence estimated at approximately 15% globally. According to the International Classification of Headache Disorders, 3rd edition (ICHD3), there are three significant types of migraine: migraine without aura (MO), migraine with aura (MA), and chronic migraine (CM), the former being the most common. Migraine diagnosis is based on official criteria specific to each type. Although a lot is already known about the origin of migraine aura, its pathophysiology is still an object of research.Long-term discussions have been held about MO and MA, with some evidence for the same underlying pathogenesis of both and other arguments against it. In this narrative review, we decided to analyse multiple factors from the perspective of similarities and differences between these two types of migraine. The aim was to understand better the bases underlying both types of migraine.Aspects such as genetics, molecular bases, relation with hormones, epidemiological and clinical features, neuroimaging, neurophysiology, treatment response, and migraine complications are covered to find similarities and differences between MO and MA. Although epidemiology shares similarities for both types, there are slight alterations in sex and age distribution. Genetics and pathogenesis showed some crucial differences. Conditions, such as vestibular symptoms and depression, were found to correlate similarly with both types of migraine. For some features, including increased cardiovascular risk, the tendency appeared to be the same; however, migraine types differ in the strength of correlation. Finally, in cases such as hormones, the influence has shown opposite directions. Therefore, although migraine with and without aura are considered two types of the same disease, more research should focus on their differences, thus finally enabling better specific treatment options for both types of migraine.