title: Stroke-free survival and its determinants in patients with symptomatic vertebrobasilar stenosis: a multicenter study.
abstract: OBJECTIVE
  We sought to determine the long-term stroke-free survival of patients who present with ischemic events related to intracranial vertebrobasilar stenosis.
  
  
  METHODS
  A retrospective cohort of patients diagnosed with symptomatic vertebrobasilar stenosis on the basis of magnetic resonance angiography and/or conventional angiography was identified at four academic medical centers. Patients' clinical and follow-up information was obtained through hospitalization records, clinic visits, and telephone interviews. Kaplan-Meier analysis was performed to determine the rate of stroke-free survival for a 5-year period. Cox proportional hazards analysis was performed to determine the effect of demographic and clinical factors on stroke-free survival.
  
  
  RESULTS
  A total of 102 patients were included, whose mean age was 64 +/- 12 years. Fifty-five (54%) of the patients were men. The mean follow-up period was 15 +/- 15.9 months (range, 1-60 mo). During the follow-up period, 14 (14%) of the patients experienced recurrent stroke. The overall mortality rate was 21% (n = 21). Stroke-free survival, calculated by using the Kaplan-Meier curve, was 76% at 12 months (95% confidence interval [CI], 66-83%) and 48% at 5 years (95% CI, 27-65%). The risk of recurrent stroke was 10.9 per 100 patient-years, and the rate of recurrent stroke and/or death was 24.2 per 100 patient-years. Cox proportional hazards analysis revealed that increasing age (hazards ratio, 1.05; 95% CI, 1.00-1.09) decreased stroke-free survival. Treatment with either antiplatelet agents or warfarin (hazards ratio, 0.018; 95% CI, 0.003-0.11) had a protective effect on stroke-free survival after adjusting for age, sex, race, hypertension, diabetes mellitus, smoking, hyperlipidemia, and lesion location.
  
  
  CONCLUSIONS
  A low rate of stroke-free survival is observed in patients with symptomatic vertebrobasilar stenosis. Further studies are required to evaluate new medical and endovascular treatment options for this group of patients to improve long-term stroke-free survival.
authors.affiliation: Department of Neurology and Neurosciences, University of Medicine and Dentistry of New Jersey, Newark, New Jersey 07103, USA. aiqureshi@hotmail.com
authors.forename: Adnan I
authors.initials: AI
authors.lastname: Qureshi
authors.forename: Wendy C
authors.initials: WC
authors.lastname: Ziai
authors.forename: Abutaher M
authors.initials: AM
authors.lastname: Yahia
authors.forename: Yousef
authors.initials: Y
authors.lastname: Mohammad
authors.forename: Souvik
authors.initials: S
authors.lastname: Sen
authors.forename: Pinky
authors.initials: P
authors.lastname: Agarwal
authors.forename: Osama O
authors.initials: OO
authors.lastname: Zaidat
authors.forename: Jose I
authors.initials: JI
authors.lastname: Suarez
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Wityk
mesh_terms: D000368:Aged; D002533:Cerebral Angiography; D015331:Cohort Studies; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D012189:Retrospective Studies; D020521:Stroke / Q000000981:diagnostic imaging / Q000209:etiology* / Q000517:prevention & control*; D013997:Time Factors; D014715:Vertebrobasilar Insufficiency / Q000150:complications* / Q000000981:diagnostic imaging / Q000628:therapy*