title: The prevalence and risk factor analysis of silent brain infarction in patients with first-ever ischemic stroke.
abstract: BACKGROUND
  To evaluate the prevalence and to identify the risk factors of silent brain infarction (SBI) in patients with ischemic stroke.
  
  
  METHODS
  A 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.
  
  
  RESULTS
  The 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).
  
  
  CONCLUSIONS
  The 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.
authors.affiliation: Department of Neurology, CHA University School of Medicine, Bundang-gu, Seongnam, Republic of Korea.
authors.forename: Seung-Hun
authors.initials: SH
authors.lastname: Oh
authors.forename: Nam-Keun
authors.initials: NK
authors.lastname: Kim
authors.forename: Sang-Heum
authors.initials: SH
authors.lastname: Kim
authors.forename: Jin-Kyeoung
authors.initials: JK
authors.lastname: Kim
authors.forename: Hyun-Sook
authors.initials: HS
authors.lastname: Kim
authors.forename: Won-Chan
authors.initials: WC
authors.lastname: Kim
authors.forename: Ok-Joon
authors.initials: OJ
authors.lastname: Kim
mesh_terms: D000368:Aged; D000704:Analysis of Variance; D001921:Brain / Q000473:pathology; D020520:Brain Infarction / Q000453:epidemiology* / Q000209:etiology / Q000473:pathology; D005260:Female; D006801:Humans; D016015:Logistic Models; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D009413:Nerve Fibers, Myelinated / Q000473:pathology; D015995:Prevalence; D012307:Risk Factors; D020521:Stroke / Q000145:classification / Q000150:complications / Q000453:epidemiology*