title: Risk factors for functional decline in older adults with arthritis.
abstract: OBJECTIVE
  Functional limitation is a major factor in medical costs. This study was undertaken to evaluate the prevalence of functional limitation among adults with arthritis and the frequency of functional decline over 2 years, and to investigate factors amenable to public health intervention that predict functional decline.
  
  
  METHODS
  Longitudinal data (1998-2000) from a cohort of 5,715 adults ages 65 years or older with arthritis from a national probability sample were analyzed. Function was defined based on ability to perform basic activities of daily living (ADL) tasks and instrumental ADL. Adjusted odds ratios (ORs) from a multiple logistic regression model were used to estimate the associations between functional decline and comorbid conditions, health behaviors, and economic factors.
  
  
  RESULTS
  Overall, 19.7% of this cohort had functional limitation at baseline, including 12.9% with ADL limitations. Over the subsequent 2 years, function declined in 13.6% of those at risk. Functional decline was most frequent among women (15.0%) and minorities (18.0% Hispanics, 18.7% African Americans) with arthritis. Lack of regular vigorous physical activity, the most prevalent risk factor (64%), almost doubled the odds of functional decline (adjusted OR 1.9, 95% confidence interval 1.5-2.4) after controlling for all risk factors. It was found that if all subjects engaged in regular vigorous physical activity, the expected functional decline could be reduced as much as 32%. Other significant predictors included older age, cognitive impairment, depressive symptoms, diabetes, physical limitations, no alcohol use, stroke, and vision impairment.
  
  
  CONCLUSIONS
  Lack of regular vigorous physical activity is a potentially modifiable risk factor that could substantially reduce functional decline and associated health care costs. Prevention/intervention programs should include regular vigorous physical activity, weight maintenance, and medical intervention for health needs. (c) 2005, American College of Rheumatology.
authors.affiliation: Feinberg School of Medicine and Multidisciplinary Clinical Research Center in Rheumatology, Northwestern University, Chicago, Illinois 60611, USA. ddunlop@northwestern.edu
authors.forename: Dorothy D
authors.initials: DD
authors.lastname: Dunlop
authors.forename: Pamela
authors.initials: P
authors.lastname: Semanik
authors.forename: Jing
authors.initials: J
authors.lastname: Song
authors.forename: Larry M
authors.initials: LM
authors.lastname: Manheim
authors.forename: Vivian
authors.initials: V
authors.lastname: Shih
authors.forename: Rowland W
authors.initials: RW
authors.lastname: Chang
mesh_terms: D000203:Activities of Daily Living; D000368:Aged; D000369:Aged, 80 and over; D001168:Arthritis / Q000453:epidemiology / Q000503:physiopathology*; D015897:Comorbidity; D004185:Disability Evaluation; D006233:Persons with Disabilities / Q000706:statistics & numerical data*; D018450:Disease Progression; D005260:Female; D016330:Frail Elderly; D015577:Geriatric Assessment; D006801:Humans; D007087:Illinois / Q000453:epidemiology; D008297:Male; D015995:Prevalence; D011596:Psychomotor Disorders / Q000453:epidemiology / Q000503:physiopathology*; D012307:Risk Factors