title: Prognostic value of functional performance for mortality in patients with peripheral artery disease.
abstract: OBJECTIVE
  Among persons with lower extremity peripheral artery disease (PAD), we determined whether objective measures of walking performance predict mortality independently of the ankle brachial index (ABI).
  
  
  BACKGROUND
  The ability of office-based functional performance measures to predict mortality in patients with PAD is unknown.
  
  
  METHODS
  Participants were 444 persons with PAD followed prospectively for 4.8 years. The 6-min walk and 4-m walks at usual and fastest pace were measured at baseline. Cox proportional hazard models were used to assess relations between baseline measures of lower extremity performance with mortality, adjusting for confounders.
  
  
  RESULTS
  One hundred twenty-seven patients (28.6%) died during follow-up. Adjusting for age, gender, race, comorbidities, ABI, and other confounders, participants in the poorest baseline quartile of 6-min walk performance had significantly increased total mortality (hazard ratio [HR] 2.36 [95% confidence interval (CI) 1.33 to 4.18]) and cardiovascular mortality (HR 5.59 [95% CI 1.97 to 15.9]) compared with the best quartile of baseline performance. Participants in the poorest baseline quartile of normal-paced 4-m walking speed had significantly increased total mortality (HR 1.86 [95% CI 1.06 to 3.29]) and cardiovascular mortality (HR 2.55 [95% CI 1.01 to 6.46]) compared with the best quartile of baseline performance.
  
  
  CONCLUSIONS
  This study demonstrates for the first time that performance-based measures, which can be administered in an office setting, provide prognostic information regarding mortality in persons with PAD beyond that provided by the ABI.
authors.affiliation: Department of Medicine, Northwestern University's Feinberg School of Medicine, Chicago, Illinois, USA. mdm608@northwestern.edu
authors.forename: Mary M
authors.initials: MM
authors.lastname: McDermott
authors.forename: Lu
authors.initials: L
authors.lastname: Tian
authors.forename: Kiang
authors.initials: K
authors.lastname: Liu
authors.forename: Jack M
authors.initials: JM
authors.lastname: Guralnik
authors.forename: Luigi
authors.initials: L
authors.lastname: Ferrucci
authors.forename: Jin
authors.initials: J
authors.lastname: Tan
authors.forename: William H
authors.initials: WH
authors.lastname: Pearce
authors.forename: Joseph R
authors.initials: JR
authors.lastname: Schneider
authors.forename: Michael H
authors.initials: MH
authors.lastname: Criqui
mesh_terms: D000368:Aged; D005080:Exercise Test; D017079:Exercise Tolerance; D005260:Female; D005500:Follow-Up Studies; D006304:Health Status; D006801:Humans; D007866:Leg / Q000098:blood supply*; D008297:Male; D009043:Motor Activity; D016491:Peripheral Vascular Diseases / Q000401:mortality* / Q000503:physiopathology*; D011237:Predictive Value of Tests; D011379:Prognosis; D011446:Prospective Studies; D016138:Walking