title: Lower extremity performance is associated with daily life physical activity in individuals with and without peripheral arterial disease.
abstract: OBJECTIVE
  To determine whether persons with poorer lower extremity functioning have reduced physical activity levels.
  
  
  METHODS
  Cross-sectional.
  
  
  METHODS
  Three Chicago-area medical centers.
  
  
  METHODS
  Two hundred twenty-five people with lower extremity peripheral arterial disease (PAD) and 121 individuals without PAD.
  
  
  METHODS
  The summary performance score (SPS) was determined for all participants. The SPS combines data on walking velocity, time for five repeated chair rises, and standing balance. Each test is scored on a 0 to 4 scale (4 = best). Scores are summed to create the SPS (0-12 scale, 12 = best). All participants wore a vertical accelerometer for 7 days to measure physical activity.
  
  
  RESULTS
  The SPS was associated linearly with 7-day physical activity levels of participants with (P< .0001) and without PAD (P< .0001). This relationship was maintained even after restricting analyses to subsets of participants who reported that they could walk a quarter of a mile and up and down stairs without difficulty (P< .001) and were able to walk for 6-minutes without stopping (P< .001). In multiple linear regression analyses, the SPS was associated with physical activity in participants with (P< .01) and without PAD (P< .001), adjusting for age, sex, race, comorbidities, ankle brachial index, neuropathy, and leg symptoms.
  
  
  CONCLUSIONS
  In people with and without PAD who have impaired lower extremity performance, reduced physical activity levels may contribute to subsequent disability. Future study is needed to determine whether interventions to increase physical activity can prevent functional decline in persons with a low SPS.
authors.affiliation: Department of Medicine, Northwestern University Medical School, Chicago, Illinois, USA. mdm608@northwestern.edu
authors.forename: Mary McGrae
authors.initials: MM
authors.lastname: McDermott
authors.forename: Philip
authors.initials: P
authors.lastname: Greenland
authors.forename: Luigi
authors.initials: L
authors.lastname: Ferrucci
authors.forename: Michael H
authors.initials: MH
authors.lastname: Criqui
authors.forename: Kiang
authors.initials: K
authors.lastname: Liu
authors.forename: Leena
authors.initials: L
authors.lastname: Sharma
authors.forename: Cheeling
authors.initials: C
authors.lastname: Chan
authors.forename: Lillian
authors.initials: L
authors.lastname: Celic
authors.forename: Aparna
authors.initials: A
authors.lastname: Priyanath
authors.forename: Jack M
authors.initials: JM
authors.lastname: Guralnik
mesh_terms: D000203:Activities of Daily Living; D000368:Aged; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D015444:Exercise; D005260:Female; D006801:Humans; D007383:Intermittent Claudication / Q000534:rehabilitation; D007866:Leg / Q000098:blood supply*; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016491:Peripheral Vascular Diseases / Q000175:diagnosis / Q000534:rehabilitation*