The prevalence and risk factor analysis of silent brain infarction in patients with first-ever ischemic stroke

Abstract

BackgroundTo evaluate the prevalence and to identify the risk factors of silent brain infarction (SBI) in patients with ischemic stroke. MethodsA total of 395 consecutive patients with first-ever ischemic stroke that underwent brain MRI were enrolled in this study. The prevalences of vascular risk factors in a SBI-positive (n=132) and in a SBI-negative group (n=263) were compared. The prevalences and characteristics of SBI were further evaluated with respect to stroke subtype and periventricular white-matter hyperintensity (PWMH) lesion. ResultsThe frequency of SBI among the 395 study subjects was 33.4%, and 10.1% of the study subjects had multiple-SBI lesions. The most common lesion site was basal ganglia (47%). Multiple logistic regression analysis showed that hypertension (OR: 1.94, 95% CI: 1.22–3.07, P=0.005) and the presence of an advanced PWMH lesion (OR: 1.77, 95% CI: 1.06–2.96, P=0.030) were significantly associated with SBI. Furthermore, an advanced PWMH lesion (OR: 2.88, 95% CI: 1.19–6.95, P=0.010) was more associated with multiple-SBI lesions than with a single-SBI lesion. The frequency of SBI was higher among those with the small-vessel disease type (45.5%) than in those with the large-artery disease (32.5%) or cardioembolic stroke type (25.6%) (P=0.04). ConclusionsThe prevalence of SBI in patients with ischemic stroke was found to be high, and hypertension was found to be the most important risk factor of SBI. Small-vessel disease and a diffuse white-matter lesion were found to be closely associated with SBI, and especially with multiple-SBI lesions.