Higher fibrinogen levels contributes to thrombosis in intracranial atherosclerosis-related large vessel occlusion strokes

Background The mechanisms underlying large-vessel occlusion strokes (LVOS) caused by intracranial atherosclerosis (ICAS) remain incompletely understood. This study aimed to characterize the distinct features of ICAS-LVOS to elucidate its pathological basis. Methods We conducted a cross-sectional analysis of a prospective, single-center cohort of acute ischemic stroke patients (January 2017 to January 2023). Participants were classified into three groups: ICAS-LVOS, atrial fibrillation-related LVOS (AF-LVOS), and symptomatic ICAS without LVOS (sICAS). Clinical and laboratory data were compared. Results The study included 279 patients, comprising 70 ICAS-LVOS patients, 78 AF-LVOS patients, and 131 sICAS patients. Compared to AF-LVOS, ICAS-LVOS patients demonstrated associations with younger age (OR: 0.898; p = 0.007), previous stroke (OR: 6.672; p = 0.031), posterior circulation involvement (OR: 30.299; p = 0.011) and higher fibrinogen levels (OR: 3.421; p = 0.006). A ratio of fibrinogen/D-dimer ≥6 effectively identified ICAS-LVOS with high specificity. Relative to sICAS, ICAS-LVOS was associated with higher body mass index (OR: 1.176; p = 0.002), white blood cell counts (OR: 1.234; p = 0.002), and fibrinogen levels (OR: 1.600; p = 0.029). Within the ICAS-LVOS group, higher thrombus burden was correlated with hypertension (OR: 6.071; p = 0.029) and higher fibrinogen levels (OR: 2.322; p = 0.046). Notably, in patients with fibrinogen levels