Fibrosis-4 index is closely associated with clinical outcomes in acute cardioembolic stroke patients with nonvalvular atrial fibrillation

Liver cirrhosis is a confirmed risk factor for poor prognosis of stroke; however, the contribution of clinically inapparent liver fibrosis to cardioembolic stroke (CES) and its outcomes are poorly understood. This study aimed to investigate the associations between liver fibrosis—measured by the Fibrosis-4 (FIB-4) score—and stroke severity and short-term clinical outcomes of patients with acute CES due to nonvalvular atrial fibrillation (NVAF). A total of 522 patients were followed for a median of 90 days. We calculated the FIB-4 score and defined liver fibrosis as follows: likely advanced fibrosis (FIB-4 > 3.25), indeterminate advanced fibrosis (FIB-4, 1.45–3.25), and unlikely advanced fibrosis (FIB-4 < 1.45). Logistic regression analysis and Cox regression analysis were used to investigate the relations between the FIB-4 score and stroke severity, major disability at discharge, and all-cause mortality. Among these 522 acute CES patients with NVAF, the mean FIB-4 score (2.28) on admission reflected intermediate fibrosis, whereas liver enzymes were largely normal. In multivariate regression analysis, patients with advanced liver fibrosis were more likely to have a higher risk of severe stroke (OR = 2.21, 95% CI 1.04–3.54), major disability at discharge (OR = 4.59, 95% CI 1.88–11.18), and all-cause mortality (HR = 1.25, 95% CI 1.10–1.56) than their counterparts. Regarding sex, these associations were stronger in males but not significant in females. In patients with acute CES due to NVAF, advanced liver fibrosis is associated with severe stroke, major disability, and all-cause death. Our findings indicate that early screening and management of liver fibrosis may decrease stroke severity and risk of death in patients with NVAF, especially for male patients. Consequently, FIB-4 > 3.25 of male patients should receive ultrasound elastography to further determine the degree of liver fibrosis.