title: Association between life space and risk of mortality in advanced age.
abstract: OBJECTIVE
  To examine the association between life space, a measure of functional status that describes the range of movement through the environment covered during daily functioning, and the risk of mortality in older community-based persons.
  
  
  METHODS
  Two ongoing, prospective observational cohort studies of aging.
  
  
  METHODS
  Greater metropolitan Chicago area.
  
  
  METHODS
  One thousand four hundred forty-five community-based older persons without dementia.
  
  
  METHODS
  Life space was measured at baseline using a series of questions designed to measure the extent of participants' movement throughout their environment, ranging from the bedroom to out of town. The association between life space and mortality was examined using proportional hazards models adjusted for age, sex, race, and education.
  
  
  RESULTS
  Over up to 8 years of follow-up (mean 4.1 years), 329 of 1,445 (22.8%) participants died. In a proportional hazards model adjusted for age, sex, race, and education, a more-constricted life space was associated with a greater risk of death (hazard ratio=1.18, 95% confidence interval=1.09-1.27, P<.001), such that people with life spaces constricted to their immediate home environment (score=3) were approximately 1.6 times as likely to die as those whose life spaces included trips out of town (score=0). This association persisted after the addition of terms for several potential confounders, including physical activity, performance-based physical function, disability, depressive symptoms, social networks, body mass index, and number of chronic medical conditions.
  
  
  CONCLUSIONS
  Constricted life space is associated with greater risk of death in older community-based persons.
authors.affiliation: Rush Alzheimer's Disease Center, Chicago, Illinois 60612, USA. Patricia_Boyle@Rush.edu
authors.forename: Patricia A
authors.initials: PA
authors.lastname: Boyle
authors.forename: Aron S
authors.initials: AS
authors.lastname: Buchman
authors.forename: Lisa L
authors.initials: LL
authors.lastname: Barnes
authors.forename: Bryan D
authors.initials: BD
authors.lastname: James
authors.forename: David A
authors.initials: DA
authors.lastname: Bennett
mesh_terms: D000203:Activities of Daily Living / Q000523:psychology*; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D002641:Chicago / Q000453:epidemiology; D004185:Disability Evaluation; D004782:Environmental Health; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D010698:Phobic Disorders / Q000401:mortality*; D011379:Prognosis; D011446:Prospective Studies; D012307:Risk Factors; D015996:Survival Rate / Q000639:trends; D013997:Time Factors