title: Prevalence and risk factors of middle cerebral artery stenosis in asymptomatic residents in Rongqi County, Guangdong.
abstract: BACKGROUND
  Intracranial atherosclerosis is the commonest vascular lesion for ischemic stroke in Asians. Most research on risk factors for middle cerebral artery (MCA) stenosis has been conducted in symptomatic patients with ischemic stroke or transient ischemic attack. The present study aimed to investigate risk factors for MCA stenosis in an asymptomatic population in Rongqi County in Southern China.
  
  
  METHODS
  We assessed 1,068 asymptomatic subjects over 50 years of age by transcranial Doppler. Medical history documentation and investigation of biochemical markers were performed for each subject. Multivariant, unconditioned, logistic regression analyses were employed to assess the risk factors associated with MCA stenosis.
  
  
  RESULTS
  MCA stenosis was found in 63 subjects (5.9%). Male gender, advancing age, hypertension, diabetes and systolic blood pressure were significant risk factors for MCA stenosis (p < 0.001). Based on logistic regression analyses, 4 factors emerged as independent risk factors (p < 0.001) of MCA stenosis: male gender [95% confidence interval (CI) = 1.49-4.66, OR = 2.63], age (95% CI = 1.01-1.06, OR = 1.04), hypertension (95% CI = 4.57-18.35, OR = 9.16) and diabetes mellitus (95% CI = 3.09-11.29, OR = 5.9).
  
  
  CONCLUSIONS
  MCA stenosis is relatively common among asymptomatic Chinese subjects. Male gender, advanced age, hypertension and diabetes mellitus are risk factors for MCA stenosis.
authors.affiliation: Department of Neurology, First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, SAR, China. hhwpdx@yahoo.com.cn
authors.forename: Hai Wei
authors.initials: HW
authors.lastname: Huang
authors.forename: Ming Hui
authors.initials: MH
authors.lastname: Guo
authors.forename: Rui Jin
authors.initials: RJ
authors.lastname: Lin
authors.forename: Ya Li
authors.initials: YL
authors.lastname: Chen
authors.forename: Qin
authors.initials: Q
authors.lastname: Luo
authors.forename: Ying
authors.initials: Y
authors.lastname: Zhang
authors.forename: Ka Sing
authors.initials: KS
authors.lastname: Wong
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D002681:China / Q000453:epidemiology; D048909:Diabetes Complications / Q000453:epidemiology / Q000209:etiology; D005260:Female; D006801:Humans; D006973:Hypertension / Q000150:complications / Q000453:epidemiology; D020244:Infarction, Middle Cerebral Artery / Q000000981:diagnostic imaging / Q000453:epidemiology* / Q000209:etiology*; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D015995:Prevalence; D012111:Residence Characteristics / Q000706:statistics & numerical data*; D018570:Risk Assessment; D012307:Risk Factors; D012737:Sex Factors; D017585:Ultrasonography, Doppler, Transcranial