title: The vital prognosis of subclavian stenosis.
abstract: OBJECTIVE
  This study sought to assess the prognosis of subclavian stenosis (SS) as a potential marker of total and cardiovascular disease (CVD) mortality.
  
  
  BACKGROUND
  Subclavian stenosis, diagnosed by a brachial systolic pressure difference (BSPD) > or =15 mm Hg, is associated with an increased prevalence of CVD risk factors. However, the association between SS and mortality is unknown. We hypothesized that a BSPD > or =15 mm Hg would predict an increased risk of CVD events.
  
  
  METHODS
  We analyzed baseline and longitudinal data from 3 cohorts. Two were recruited from noninvasive vascular laboratories, and the third was a community-dwelling cohort. Multivariate survival models were used to test for an independent association of SS with total and CVD mortality.
  
  
  RESULTS
  Baseline and follow-up data (mean 9.8 years) were complete in 1,778 participants. Subclavian stenosis was found in 157 (8.8%) subjects. Adjusted for age, gender, ethnicity, and cohort of origin, the presence of SS was significantly associated with increased total and CVD mortality (respectively, hazard ratio [HR] 1.42, p < 0.005; and HR 1.50, p = 0.05). This association persisted after adjustments for CVD risk factors (smoking pack-years, hypertension, diabetes, total/high-density lipoprotein cholesterol ratio, and body mass index) as well as lipid-lowering and antiplatelet therapies (HR 1.40, p < 0.01; and HR 1.57, p < 0.05 for total and CVD mortality, respectively). When any history of CVD or an ankle-brachial index <0.90 were added to the model, SS remained an independent predictor for total mortality (HR 1.34, p = 0.02), with a similar trend for CVD mortality (HR 1.43, p = 0.09).
  
  
  CONCLUSIONS
  The presence of SS, easily diagnosed by comparing systolic pressures in the left and right arm, predicts total and CVD mortality independent of both CVD risk factors and existent CVD at baseline.
authors.affiliation: Department of Family and Preventive Medicine, University of California-San Diego, La Jolla, California 92093-0607, USA. vaboyans@ucsd.edu
authors.forename: Victor
authors.initials: V
authors.lastname: Aboyans
authors.forename: Michael H
authors.initials: MH
authors.lastname: Criqui
authors.forename: Mary McGrae
authors.initials: MM
authors.lastname: McDermott
authors.forename: Matthew A
authors.initials: MA
authors.lastname: Allison
authors.forename: Julie O
authors.initials: JO
authors.lastname: Denenberg
authors.forename: Ramin
authors.initials: R
authors.lastname: Shadman
authors.forename: Arnost
authors.initials: A
authors.lastname: Fronek
mesh_terms: D000368:Aged; D002318:Cardiovascular Diseases / Q000150:complications* / Q000401:mortality*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D011379:Prognosis; D013349:Subclavian Steal Syndrome / Q000150:complications* / Q000401:mortality*