Silent Cerebral Infarction is Associated with Incident Stroke and TIA Independent of Carotid Intima-Media Thickness

BACKGROUND: Both silent cerebral infarction (SCI) and carotid intima-media thickness (IMT) are associated with future stroke. We evaluated whether SCI could be a predictor for incident stroke independent of carotid IMT in high-risk patients. METHODS: We performed a prospective cohort study among 282 outpatients who had one or more atherosclerotic risk factors but without a history of cardiovascular disease. We conducted cranial MRI and measured carotid IMT at baseline, and then evaluated the risks of incident stroke and transient ischemic attacks (TIA) using Cox proportional hazards models. RESULTS: SCI was present in 67 patients (23.7%) at baseline. During 4.1 years of follow-up, stroke and TIA occurred in 8 patients (2.8%). The incidence of stroke/TIA was 22.3 per 1,000 person-years in those with SCI compared with 2.2 per 1,000 person-years in those without SCI. Both SCI and carotid IMT at baseline were associated with incident stroke/TIA events after adjustment for age, sex, and traditional vascular risk factors. The predictive value of SCI remained significant even after adjustment for carotid IMT (HR 8.56; 1.72-42.55). CONCLUSION: SCI, similar to carotid IMT, is an independent predictor of stroke and TIA in high-risk patients.