title: Respiratory impairment and dyspnea and their associations with physical inactivity and mobility in sedentary community-dwelling older persons.
abstract: OBJECTIVE
  To evaluate the prevalence of respiratory impairment and dyspnea and their associations with objectively measured physical inactivity and performance-based mobility in sedentary older persons.
  
  
  METHODS
  Cross-sectional.
  
  
  METHODS
  Lifestyle Interventions and Independence for Elders Study.
  
  
  METHODS
  Community-dwelling older persons (n = 1,635, mean age 78.9) who reported being sedentary (<20 min/wk of regular physical activity and <125 min/wk of moderate physical activity in past month).
  
  
  METHODS
  Respiratory impairment was defined as low ventilatory capacity (forced expiratory volume in 1 second less than lower limit of normal (LLN)) and respiratory muscle weakness (maximal inspiratory pressure <LLN). Dyspnea was defined as moderate to severe ratings on the modified Borg index, immediately after a 400-m walk test (400-MWT). Physical inactivity was defined according to high sedentary time as the highest quartile of participants with accelerometry-measured activity of <100 counts/min. Performance-based mobility was evaluated using the Short Physical Performance Battery (≤ 7 defined as moderate to severe mobility impairment) and 400-MWT gait speed (<0.8 m/s defined as slow).
  
  
  RESULTS
  Prevalence rates were 17.7% for low ventilatory capacity, 14.7% for respiratory muscle weakness, 31.6% for dyspnea, 44.7% for moderate to severe mobility impairment and 43.6% for slow gait speed. Significant associations were found between low ventilatory capacity and slow gait speed (adjusted odds ratio (aOR) = 1.41, 95% confidence interval (CI) = 1.03-1.92), between respiratory muscle weakness and moderate to severe mobility impairment (aOR = 1.42, 95% CI = 1.03-1.95), and between dyspnea and high sedentary time (aOR = 1.98, 95% CI = 1.28-3.06) and slow gait speed (aOR = 1.70, 95% CI = 1.22-2.38).
  
  
  CONCLUSIONS
  Respiratory impairment and dyspnea are prevalent in sedentary older persons and are associated with objectively measured physical inactivity and poor performance-based mobility. Because they are modifiable, respiratory impairment and dyspnea should be considered in the evaluation of sedentary older persons.
authors.affiliation: Veterans Affairs Connecticut, West Haven, Connecticut; Department of Medicine, School of Medicine, Yale University, New Haven, Connecticut.
authors.forename: Carlos A
authors.initials: CA
authors.lastname: Vaz Fragoso
authors.forename: Daniel P
authors.initials: DP
authors.lastname: Beavers
authors.forename: John L
authors.initials: JL
authors.lastname: Hankinson
authors.forename: Gail
authors.initials: G
authors.lastname: Flynn
authors.forename: Kathy
authors.initials: K
authors.lastname: Berra
authors.forename: Stephen B
authors.initials: SB
authors.lastname: Kritchevsky
authors.forename: Christine K
authors.initials: CK
authors.lastname: Liu
authors.forename: Mary M
authors.initials: MM
authors.lastname: McDermott
authors.forename: Todd M
authors.initials: TM
authors.lastname: Manini
authors.forename: W Jack
authors.initials: WJ
authors.lastname: Rejeski
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Gill
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003430:Cross-Sectional Studies; D004417:Dyspnea / Q000453:epidemiology / Q000503:physiopathology / Q000534:rehabilitation*; D005081:Exercise Therapy / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D005541:Forced Expiratory Volume / Q000502:physiology; D015577:Geriatric Assessment; D006801:Humans; D008019:Life Style; D008297:Male; D051346:Mobility Limitation; D010353:Patient Education as Topic; D015995:Prevalence; D012131:Respiratory Insufficiency / Q000453:epidemiology / Q000503:physiopathology / Q000534:rehabilitation*; D016138:Walking / Q000502:physiology*
keywords: FEV1; dyspnea; mobility; respiratory muscle weakness; sedentary