title: Relationship between balance and physical activity measured by an activity monitor in elderly COPD patients.
abstract: BACKGROUND
  Little is known regarding the relationship between balance impairments and physical activity in COPD. There has been no study investigating the relationship between balance and objectively measured physical activity. Here we investigated the association between balance and physical activity measured by an activity monitor in elderly COPD patients.
  
  
  METHODS
  Twenty-two outpatients with COPD (mean age, 72±7 years; forced expiratory volume in 1 second, 53%±21% predicted) and 13 age-matched healthy control subjects (mean age, 72±6 years) participated in the study. We assessed all 35 subjects' balance (one-leg standing test [OLST] times, Short Physical Performance Battery total scores, standing balance test scores, 4 m gait speed, and five-times sit-to-stand test [5STST]) and physical activity (daily steps and time spent in moderate-to-vigorous physical activity per day [MV-PA]). Possible confounders were assessed in the COPD group. The between-group differences in balance test scores and physical activity were analyzed. A correlation analysis and multivariate regression analysis were conducted in the COPD group.
  
  
  RESULTS
  The COPD patients exhibited significant reductions in OLST times (P=0.033), Short Physical Performance Battery scores (P=0.013), 4 m gait speed (P<0.001), five-times sit-to-stand times (P=0.002), daily steps (P=0.003), and MV-PA (P=0.022) compared to the controls; the exception was the standing balance test scores. The correlation and multivariate regression analyses revealed significant independent associations between OLST times and daily steps (P<0.001) and between OLST times and MV-PA (P=0.014) in the COPD group after adjusting for possible confounding factors.
  
  
  CONCLUSIONS
  Impairments in balance and reductions in physical activity were observed in the COPD group. Deficits in balance are independently associated with physical inactivity.
authors.affiliation: Department of Rehabilitation, Akita City Hospital; Department of Physical Therapy, Akita University Graduate School of Health Sciences, Akita, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Iwakura
authors.affiliation: Department of Physical Therapy, Akita University Graduate School of Health Sciences, Akita, Japan.
authors.forename: Kazuki
authors.initials: K
authors.lastname: Okura
authors.affiliation: Department of Rehabilitation, Akita City Hospital; Department of Physical Therapy, Akita University Graduate School of Health Sciences, Akita, Japan.
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Shibata
authors.affiliation: Department of Physical Therapy, Akita University Graduate School of Health Sciences, Akita, Japan.
authors.forename: Atsuyoshi
authors.initials: A
authors.lastname: Kawagoshi
authors.affiliation: Department of Physical Therapy, Akita University Graduate School of Health Sciences, Akita, Japan.
authors.forename: Keiyu
authors.initials: K
authors.lastname: Sugawara
authors.affiliation: Department of Physical Therapy, Akita University Graduate School of Health Sciences, Akita, Japan.
authors.forename: Hitomi
authors.initials: H
authors.lastname: Takahashi
authors.affiliation: Department of Rehabilitation, Akita City Hospital.
authors.forename: Takanobu
authors.initials: T
authors.lastname: Shioya
mesh_terms: D056044:Actigraphy / Q000295:instrumentation*; D000203:Activities of Daily Living; D000367:Age Factors; D000368:Aged; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D004867:Equipment Design; D015444:Exercise; D005541:Forced Expiratory Volume; D015577:Geriatric Assessment; D006801:Humans; D016014:Linear Models; D008168:Lung / Q000503:physiopathology; D008297:Male; D015999:Multivariate Analysis; D004856:Postural Balance; D011237:Predictive Value of Tests; D029424:Pulmonary Disease, Chronic Obstructive / Q000175:diagnosis / Q000503:physiopathology* / Q000534:rehabilitation; D057185:Sedentary Behavior; D012678:Sensation Disorders / Q000175:diagnosis / Q000503:physiopathology*; D013997:Time Factors; D000072797:Walking Speed
keywords: COPD; activity monitor; balance impairments; physical inactivity; pulmonary rehabilitation