Utility of Fibrinogen Levels for Predicting Survival and Functional Outcomes in Patients with Acute Ischemic Stroke: A Meta-Analysis

Background and Objective: Studies on the association between blood fibrinogen levels and adverse outcomes in patients with acute ischemic stroke have produced controversial results. This meta-analysis aimed to examine the association of elevated fibrinogen levels with adverse outcomes in acute ischemic stroke patients. Methods: Two authors comprehensively searched the articles indexed in PubMed and Embase databases until December 31, 2021. All cohort studies that assessed the value of fibrinogen level in predicting poor functional outcomes or all-cause mortality in acute ischemic stroke patients were included. Results: Nine studies reporting on ten articles involving 16,998 patients met the inclusion criteria. For the highest versus lowest fibrinogen group, the pooled adjusted risk ratio (RR) was 1.48 (95% confidence intervals [CI] 1.17-1.87) for poor functional outcomes defined by the modified Rankin Scale ≥ 3. In addition, elevated fibrinogen was not significantly associated with an increased risk of all-cause mortality (RR 1.76; 95% CI 1.42-2.20). Subgroup analysis suggested that there was no clear association between elevated fibrinogen levels and PFO in younger acute ischemic stroke patients (RR 1.16; 95% CI 0.87-1.53). Conclusion: Elevated fibrinogen level at baseline is possibly an independent predictor of short-term poor functional outcome and long-term all-cause mortality, particularly in elderly acute ischemic stroke patients. Blood fibrinogen level may serve as a useful biomarker for risk classification of acute ischemic stroke patients.