title: The effects of smoking status on walking ability and health-related quality of life in patients with peripheral arterial disease.
abstract: BACKGROUND
  Smoking is a leading risk factor for peripheral arterial disease (PAD), yet little is known about the interrelationships among smoking status, walking endurance, calf muscle tissue oxygenation, and quality of life in patients with PAD.
  
  
  OBJECTIVE
  The aim of this study was to explore the differences in factors associated with walking endurance including walk distance, perceived walking ability, measures of skeletal muscle tissue oxygenation (StO2), claudication pain, peak oxygen consumption per unit time, and quality of life in smokers versus nonsmokers.
  
  
  METHODS
  A total of 105 patients with PAD performed progressive, symptom-limited treadmill test. Ankle-brachial index was measured at baseline. Calf muscle tissue oxygenation measures were obtained during testing. The RAND Short Form-36 and Walking Impairment Questionnaire were used to measure health-related quality of life (HR-QoL).
  
  
  RESULTS
  In the total sample (36 current smokers, 69 nonsmokers), smokers had steeper declines in StO2 from baseline to 2 minutes (42.3% vs 33%, P = .05) and shorter distance walked to onset of claudication pain (142.6 vs 247.7 m) than did nonsmokers (P < .0125), despite having no differences in ankle-brachial index, peak oxygen consumption per unit time, or any momentary measure of StO2 during walking. Smokers reported significantly lower HR-QoL on the Short Form-36 in several domains but no differences in the Walking Impairment Questionnaire measures. The smokers were younger than the nonsmokers; however, when age was entered as a covariate in the analyses, the results remained unchanged.
  
  
  CONCLUSIONS
  These findings suggest that smokers have lower HR-QoL than do nonsmokers with PAD and that smoking confers risks for disrupted tissue oxygenation above those seen in patients who do not smoke.
authors.affiliation: Department of Biobehavioral Health Sciences, University of Illinois at Chicago, Illinois, USA.
authors.forename: Cynthia
authors.initials: C
authors.lastname: Fritschi
authors.forename: Eileen G
authors.initials: EG
authors.lastname: Collins
authors.forename: Susan
authors.initials: S
authors.lastname: O'Connell
authors.forename: Conor
authors.initials: C
authors.lastname: McBurney
authors.forename: Jolene
authors.initials: J
authors.lastname: Butler
authors.forename: Lonnie
authors.initials: L
authors.lastname: Edwards
mesh_terms: D000368:Aged; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D018482:Muscle, Skeletal / Q000378:metabolism; D010100:Oxygen / Q000378:metabolism; D016491:Peripheral Vascular Diseases / Q000378:metabolism / Q000503:physiopathology*; D011788:Quality of Life; D012907:Smoking / Q000009:adverse effects*; D016138:Walking
chemical_list: D010100:Oxygen