Lower fibrinogen and fibrinogen-to-albumin ratio in migraine with white matter hyperintensities: implications for microvascular vulnerability

White matter hyperintensities (WMH) are increasingly recognized as imaging markers of migraine-related cerebral small-vessel injury. However, the biological correlates underlying WMH in migraine remain poorly defined. The relationship between WMH and the fibrinogen-to-albumin ratio (FAR), a composite hemostatic marker, has not yet been evaluated. In this cross-sectional study, 69 patients with migraine were included after exclusion of systemic inflammatory and vascular confounders. WMH presence was assessed using brain magnetic resonance imaging (MRI). Plasma fibrinogen and albumin levels were measured during the interictal period, and FAR was calculated. C-reactive protein (CRP) and inflammatory indices derived from complete blood counts were also analyzed. Multivariable regression analyses were performed with adjustment for age and sex. Patients with WMH had significantly lower fibrinogen levels and FAR compared to those without WMH ( p = 0.003 and p = 0.004, respectively). After adjustment for age and sex, WMH remained independently associated with lower fibrinogen levels and FAR ( p = 0.002 for both). No differences were observed in CRP or other systemic inflammatory markers. WMH in migraine were independently associated with lower fibrinogen levels and FAR. These findings suggest that WMH in migraine may reflect microvascular vulnerability associated with altered hemostatic balance rather than systemic inflammation. Further longitudinal studies are needed to clarify the underlying mechanisms and clinical implications.