Migraine and stroke: correlation, coexistence, dependence - a modern perspective.

Background: Migraine is a chronic neurological condition that has a well-documented, yet not fully understood connection to stroke, particularly in patients who experience migraine with aura (MA). Although migraine can rarely be directly related to stroke, in the form of migrainous infarction, it serves as an independent risk factor, particularly when combined with other factors such as smoking or hypertension. This study will thoroughly review and summarize the existing literature regarding the relationship between migraine and stroke.

Main text: Several key processes are common to both stroke and migraine. These include cortical spreading depression, particularly in MA, endothelial dysfunction, which activates local inflammatory responses, and vasculopathy, which often appears as white matter hyperintensities on neuroimaging. Furthermore, microRNAs also play a significant role in the pathogenesis of both migraine and stroke by targeting genes such as CALCA, which regulates calcitonin gene-related peptide, a factor involved in the pathophysiology of both conditions. There are also several genetic links between migraine and stroke, including both monogenic diseases and common risk loci. Moreover, various conditions are linked to both migraine and stroke, including patent foramen ovale (PFO), atrial fibrillation, carotid artery dissection, platelet dysfunction, dyslipidemia, obesity, hyperhomocysteinemia, and elevated estrogen levels, such as in combined hormonal contraceptives. Notably, PFO is often found in patients who have experienced a cryptogenic stroke, as well as in those with MA. While microemboli associated with PFO may provoke ischemic events and migraine attacks, the effectiveness of PFO closure in alleviating migraine symptoms has produced varying results. Migraine is linked to worse outcomes after ischemic stroke, including larger stroke volumes and poorer functional outcomes, while the connection between migraines and hemorrhagic stroke is less understood. Furthermore, migraine may serve as a stroke mimic (condition presenting with symptoms similar to ischemic stroke) or a stroke chameleon (unrecognized stroke misdiagnosed as migraine), leading to significant diagnostic and treatment errors.

Conclusions: The interplay between migraine and stroke is complex, involving shared pathophysiology and overlapping risk factors. While migraine can serve as both a cause and a risk factor for stroke, the precise mechanisms remain unclear, warranting further research to clarify their connection and enhance clinical management.