Vascular biomarkers in migraine.

AIM: Migraine has been associated with stroke as well as with several non-atherosclerotic vascular conditions leading to discussions about the potential role of endothelium in the etiopathogenesis of migraine and migraine-associated stroke. We present a systematic review of the literature on vascular biomarkers in migraine, including those suggesting endothelial activation and damage. METHODS: We conducted a systematic literature search from 1990 to 2013 using multiple research databases with the keywords "migraine," "headache," "vascular," and "biomarkers." We used selected inclusion and exclusion criteria to create a final pool of studies for this review. RESULTS: The literature search identified a total of 639 citations of which 129 were included in our review. The final pool of clinical- and population-based studies assessed the level of various biomarkers (e.g. inflammatory, prothrombotic, endothelial activation, endothelial repair) in migraineurs of varying ages, gender, and demographic characteristics. Although for each biomarker there is at least one study suggesting an association with migraine, in many cases the quality of evidence is poor and there are conflicting studies showing no relationship. The results were, therefore, in each case inconclusive. CONCLUSION: This systematic review indicated that in migraine populations there are a number of positive vascular biomarker studies, including some involving novel biomarkers such as endothelial microparticles and endothelial precursor cells. These lend insight into possible pathophysiological mechanisms by which migraine may be associated with stroke. More high-quality studies are needed to establish whether a true association between promising vascular biomarkers and migraine exists.