title: Association of 6-Minute Walk Performance and Physical Activity With Incident Ischemic Heart Disease Events and Stroke in Peripheral Artery Disease.
abstract: BACKGROUND
  We determined whether poorer 6-minute walk performance and lower physical activity levels are associated with higher rates of ischemic heart disease (IHD) events in people with lower extremity peripheral artery disease (PAD).
  
  
  RESULTS
  Five hundred ten PAD participants were identified from Chicago-area medical centers and followed prospectively for 19.0±9.5 months. At baseline, participants completed the 6-minute walk and reported number of blocks walked during the past week (physical activity). IHD events were systematically adjudicated and consisted of new myocardial infarction, unstable angina, and cardiac death. For 6-minute walk, IHD event rates were 25/170 (14.7%) for the third (poorest) tertile, 10/171 (5.8%%) for the second tertile, and 6/169 (3.5%) for the first (best) tertile (P=0.003). For physical activity, IHD event rates were 21/154 (13.6%) for the third (poorest) tertile, 15/174 (8.6%) for the second tertile, and 5/182 (2.7%) for the first (best) tertile (P=0.001). Adjusting for age, sex, race, smoking, body mass index, comorbidities, and physical activity, participants in the poorest 6-minute walk tertile had a 3.28-fold (95% CI 1.17 to 9.17, P=0.024) higher hazard for IHD events, compared with those in the best tertile. Adjusting for confounders including 6-minute walk, participants in the poorest physical activity tertile had a 3.72-fold (95% CI 1.24 to 11.19, P=0.019) higher hazard for IHD events, compared with the highest tertile.
  
  
  CONCLUSIONS
  Six-minute walk and physical activity predict IHD event rates in PAD. Further study is needed to determine whether interventions that improve 6-minute walk, physical activity, or both can reduce IHD events in PAD.
authors.affiliation: Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL (M.M.M.D., P.G., D.G., J.T.W., M.D.H., S.J.S., D.M.L.J.) Department of Preventive Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL (M.M.M.D., P.G., L.Z., K.L., J.T.W., M.D.H., Y.L., D.M.L.J.).
authors.forename: Mary M
authors.initials: MM
authors.lastname: McDermott
authors.affiliation: Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL (M.M.M.D., P.G., D.G., J.T.W., M.D.H., S.J.S., D.M.L.J.) Department of Preventive Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL (M.M.M.D., P.G., L.Z., K.L., J.T.W., M.D.H., Y.L., D.M.L.J.).
authors.forename: Philip
authors.initials: P
authors.lastname: Greenland
authors.affiliation: Department of Health Research and Policy, Stanford University, Stanford, CA (L.T.).
authors.forename: Lu
authors.initials: L
authors.lastname: Tian
authors.affiliation: Department of Surgery, Northwestern University Feinberg School of Medicine, Chicago, IL (M.R.K.) Jesse Brown Veterans Affairs Medical Center, Chicago, IL (M.R.K.).
authors.forename: Melina R
authors.initials: MR
authors.lastname: Kibbe
authors.affiliation: Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL (M.M.M.D., P.G., D.G., J.T.W., M.D.H., S.J.S., D.M.L.J.).
authors.forename: David
authors.initials: D
authors.lastname: Green
authors.affiliation: Department of Preventive Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL (M.M.M.D., P.G., L.Z., K.L., J.T.W., M.D.H., Y.L., D.M.L.J.).
authors.forename: Lihui
authors.initials: L
authors.lastname: Zhao
authors.affiliation: Department of Family and Preventive Medicine, University of California at San Diego, La Jolla, CA (M.H.C.).
authors.forename: Michael H
authors.initials: MH
authors.lastname: Criqui
authors.affiliation: Department of Epidemiology and Public Health, University of Maryland School of Medicine, Baltimore, MD (J.M.G.).
authors.forename: Jack M
authors.initials: JM
authors.lastname: Guralnik
authors.affiliation: National Institute on Aging, Bethesda, MD (L.F.).
authors.forename: Luigi
authors.initials: L
authors.lastname: Ferrucci
authors.affiliation: Department of Preventive Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL (M.M.M.D., P.G., L.Z., K.L., J.T.W., M.D.H., Y.L., D.M.L.J.).
authors.forename: Kiang
authors.initials: K
authors.lastname: Liu
authors.affiliation: Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL (M.M.M.D., P.G., D.G., J.T.W., M.D.H., S.J.S., D.M.L.J.) Department of Preventive Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL (M.M.M.D., P.G., L.Z., K.L., J.T.W., M.D.H., Y.L., D.M.L.J.).
authors.forename: John T
authors.initials: JT
authors.lastname: Wilkins
authors.affiliation: Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL (M.M.M.D., P.G., D.G., J.T.W., M.D.H., S.J.S., D.M.L.J.) Department of Preventive Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL (M.M.M.D., P.G., L.Z., K.L., J.T.W., M.D.H., Y.L., D.M.L.J.).
authors.forename: Mark D
authors.initials: MD
authors.lastname: Huffman
authors.affiliation: Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL (M.M.M.D., P.G., D.G., J.T.W., M.D.H., S.J.S., D.M.L.J.).
authors.forename: Sanjiv J
authors.initials: SJ
authors.lastname: Shah
authors.affiliation: Department of Preventive Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL (M.M.M.D., P.G., L.Z., K.L., J.T.W., M.D.H., Y.L., D.M.L.J.).
authors.forename: Yihua
authors.initials: Y
authors.lastname: Liao
authors.affiliation: Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL (M.M.M.D., P.G., D.G., J.T.W., M.D.H., S.J.S., D.M.L.J.) Department of Preventive Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL (M.M.M.D., P.G., L.Z., K.L., J.T.W., M.D.H., Y.L., D.M.L.J.).
authors.forename: Donald M
authors.initials: DM
authors.lastname: Lloyd-Jones
mesh_terms: D000368:Aged; D000789:Angina, Unstable / Q000503:physiopathology; D055109:Ankle Brachial Index; D005260:Female; D006801:Humans; D008297:Male; D009043:Motor Activity / Q000502:physiology*; D017202:Myocardial Ischemia / Q000503:physiopathology*; D058729:Peripheral Arterial Disease / Q000150:complications*; D011446:Prospective Studies; D020521:Stroke / Q000503:physiopathology*; D016138:Walking / Q000502:physiology*
keywords: intermittent claudication; peripheral vascular disease