Predictors of cerebral microbleeds in acute ischemic stroke and TIA patients.

BACKGROUND: Cerebral microbleeds (CMB) detected on gradient-echo T2*-weighted MRI have been associated with cognitive impairment and the potential for increased risk of intracranial hemorrhage. We evaluated risk factors for these microangiopathic lesions in a cohort of stroke and transient ischemic attack patients.
METHODS: Presence and number of CMB in consecutive acute stroke patients admitted to a university hospital stroke service over an 18-month period were rated. Multivariate models were generated to determine the contribution of 21 demographic and clinical variables to the frequency and number of CMB.
RESULTS: Of 164 patients (mean age 71 years, 52% female), 57 (35%) had CMB evident on gradient-echo T2*-weighted MRI. CMB were more commonly noted among patients with small vessel disease ischemic stroke mechanism (47%) than large vessel atherothromboembolic (12%) or cardioembolic (18%, p = 0.0001). In univariate analysis, patients with CMB were older, (p = 0.008), more likely to have been on >1 antihypertensive prior to admission (p = 0.024) than those without CMB. In multivariate logistic regression analyses, presumed small vessel stroke subtype, history of atrial fibrillation, being on >1 antihypertensive prior to admission, and smoking were independent factors increasing the risk of CMB. Logistic regression analysis by number of CMB showed almost similar findings.
CONCLUSIONS: CMB are more frequently noted in hospitalized stroke and transient ischemic attack patients with small vessel ischemia, as well as those with important modifiable vascular risk factors like atrial fibrillation and smoking. Copyright (c) 2006 S. Karger AG, Basel.