Background: Fibrinogen is a central protein of hemostasis and a major determinant of plasma viscosity and key factor for platelet activation. In acute ischemic stroke patients, higher levels of plasma fibrinogen are associated with increased risk of unfavorable functional outcome and mortality. The aim of this study is to investigate the relationship between fibrinogen level and short-term outcome in acute ischemic stroke patients receiving intravenous thrombolysis.
Methods: This retrospective study included 176 acute ischemic stroke patients who received intravenous thrombolysis with recombinant tissue plasminogen activator and provided plasma fibrinogen level within 24 hours after stroke onset. Patients were categorized by plasma fibrinogen level: Quartile 1 (≤ 1.74 g/L), Quartile 2 (1.75–2.08 g/L), Quartile 3 (2.09–2.69 g/L), and Quartile 4 (> 2.69 g/L). The medical record of each patient was reviewed, and demographic, clinical and laboratory information was abstracted. Functional outcome at 14 days was assessed with the modified Rankin Scale.
Results: Poor outcome was present in 75 (42.6%) of the 176 patients that were included in the study (mean age, 72 years; male, 53.4%). In the patients with poor outcome, plasma fibrinogen levels were significantly higher compared with those in patients with good outcomes [2.6 (IQR, 1.8-3.2) g/L vs 2.0 (IQR, 1.7-2.4) g/L; Z= −3.90, P < 0.05]. After adjustment for potential confounding variables, higher plasma fibrinogen level on admission was associated with poor outcome (adjusted odds ratio 10.45, 95% confidence interval 1.49-73.15 for Q4:Q1; P = 0.02). According to receiver operating characteristic analysis, the best discriminating factor for poor outcome was a plasma fibrinogen level ≥ 2.585 g/L (area under the curve 0.672; sensitivity 50.7%; specificity 86.1%). Conclusion: Elevated plasma fibrinogen levels on admission are significantly associated with poor outcome after admission for acute ischemic stroke, suggesting the potential role of plasma fibrinogen level as a predictive marker for short-term poor outcome in acute ischemic stroke patients receiving thrombolytic therapy.