title: A Study Design to Evaluate Association between Smoking and Intracranial Atherosclerotic Stenosis.
abstract: OBJECTIVE
  Smoking is a well known risk factor for stroke. The cerebral arteries may be uniquely susceptible to the atherosclerotic effects of smoking, such that it has a different risk profile for stroke compared with other atherosclerosis risk factors. It remains uncertain whether smoking is associated specifically with intracranial (IC) or extracranial (EC) atherosclerotic cerebrovascular disease. The aim of this study design will be to evaluate the association between smoking and severe IC stenosis, adjusting for other atherosclerosis risk factors, particularly age distribution.
  
  
  METHODS
  This is a retrospective cohort study design. Participants are patients (n=1714) with severe atherosclerotic stenosis undergoing cerebral catheter angiography because of stroke or transient ischaemic attack. All atherosclerotic steno-occlusive lesions are described in terms of location (anterior versus posterior circulation, IC versus EC, or intradural versus extradural). The atherosclerotic or stroke risk factors for analysis include age, gender, smoking history, number of lesions (single versus multiple), cardiac disease, diabetes mellitus, hypertension, family history, dyslipidemia, history of previous stroke, alcohol intake, metabolic syndrome and body mass index. Statistical analysis includes univariate analysis followed by multivariate logistic regression. The relationship between IC atherosclerotic stenosis and smoking will be assessed. Differences in risk factor distribution is analysed according to age at intervals of 10 years. Significant risk factors associated with IC atherosclerotic stenosis will also be assessed by multivariate logistic regression analysis.
  
  
  CONCLUSIONS
  This is an analytical study design that intends to measure the association between IC or EC atherosclerotic stenosis and smoking and other risk factors. We anticipate that it will have the power to detect any relationship between smoking and IC atherosclerotic lesions especially in younger patients.
authors.affiliation: Department of Radiology and Research Institute of Radiology, University of Ulsan, College of Medicine, Asan Medical Center, Seoul, Korea. ; Department of Interventional Radiology, Taizhou People's Hospital, Taizhou, Jiangsu Province 225300, P. R. China.
authors.forename: Hairi
authors.initials: H
authors.lastname: Liu
authors.affiliation: Department of Radiology and Research Institute of Radiology, University of Ulsan, College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Dong-Geun
authors.initials: DG
authors.lastname: Lee
authors.affiliation: Department of Radiology and Research Institute of Radiology, University of Ulsan, College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Seung Chul
authors.initials: SC
authors.lastname: Jung
authors.affiliation: Department of Radiology and Research Institute of Radiology, University of Ulsan, College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Hyun Jung
authors.initials: HJ
authors.lastname: Koo
authors.affiliation: Department of Radiology and Research Institute of Radiology, University of Ulsan, College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Eun Hye
authors.initials: EH
authors.lastname: Kim
authors.affiliation: Department of Radiology and Research Institute of Radiology, University of Ulsan, College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Seon Moon
authors.initials: SM
authors.lastname: Hwang
authors.affiliation: Department of Neurology, University of Ulsan, College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Bum Joon
authors.initials: BJ
authors.lastname: Kim
authors.affiliation: Department of Neurology, University of Ulsan, College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Yeonjung
authors.initials: Y
authors.lastname: Kim
authors.affiliation: Department of Family Medicine, University of Ulsan, College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Hong Jun
authors.initials: HJ
authors.lastname: Cho
authors.affiliation: Department of Clinical Epidemiology and Biostatistics, University of Ulsan, College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Min-Ju
authors.initials: MJ
authors.lastname: Kim
authors.affiliation: Department of Clinical Epidemiology and Biostatistics, University of Ulsan, College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Seung Hee
authors.initials: SH
authors.lastname: Baek
authors.affiliation: Department of Neurology, University of Ulsan, College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Sang-Beom
authors.initials: SB
authors.lastname: Jeon
authors.affiliation: Department of Neurology, University of Ulsan, College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Jong Sung
authors.initials: JS
authors.lastname: Kim
authors.affiliation: Department of Radiology and Research Institute of Radiology, University of Ulsan, College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Dae Chul
authors.initials: DC
authors.lastname: Suh
keywords: Atherosclerosis; Risk Factors; Smoking; Stenosis