The Impacts of C-Reactive Protein and Atrial Fibrillation on Carotid Atherosclerosis and Ischemic Stroke in Patients with Suspected Ischemic Cerebrovascular Disease: A Single-Center Retrospective Observational Cohort Study

BACKGROUND AND OBJECTIVES: Carotid intima-media thickness (IMT) is associated with chronic inflammation, and C-reactive protein (CRP) level is elevated in patients with atrial fibrillation (AF). We investigated the impacts of CRP and AF on carotid atherosclerosis and ischemic stroke in patients with suspected ischemic cerebrovascular disease. SUBJECTS AND METHODS: One-hundred forty patients (78 males) with suspected ischemic cerebrovascular disease underwent carotid ultrasonography. The mean common carotid artery IMT, mean internal carotid artery (ICA) IMT, and plaque score were measured. Patients were divided into four groups according to the presence of AF and elevated CRP level {n=46 for AF(-)CRP(-), n=38 for AF(-)CRP(+), n=43 for AF(+)CRP(-), and n=13 for AF(+)CRP(+)}. RESULTS: Common carotid artery IMT was significantly higher in the AF(-)CRP(+) (0.98±0.51 mm) and AF(+)CRP(+) (0.96±0.27 mm) groups compared to the AF(-)CRP(-) (0.80±0.32 mm) and AF(+)CRP(-) (0.77±0.19 mm) groups (p=0.027). Although there was no significant difference in mean ICA IMT among the groups, plaque score was the highest in the AF(+)CRP(+) (4.18±3.84 mm) group, followed by AF(-)CRP(+) (3.87±2.78 mm), AF(+)CRP(-) (1.34±2.61 mm), and AF(-)CRP(-) (1.17±2.02 mm) (p<0.001). The AF(+)CRP(+) group showed significantly higher incidence of ischemic stroke than the other groups (all p<0.05). Binary logistic regression analysis showed that age {odds ratio (OR)=1.033, p=0.001}, elevated CRP (OR=3.884, p=0.001), and the presence of AF (OR=1.375, p=0.018) were significantly correlated with incidence of ischemic stroke. CONCLUSION: Elevated plasma CRP concentration may be a reliable surrogate marker for predicting carotid atherosclerosis in patients with AF, which may be related to increased risk of ischemic stroke.