title: Gait Speed Predicts Incident Disability: A Pooled Analysis.
abstract: BACKGROUND
  Functional independence with aging is an important goal for individuals and society. Simple prognostic indicators can inform health promotion and care planning, but evidence is limited by heterogeneity in measures of function.
  
  
  METHODS
  We performed a pooled analysis of data from seven studies of 27,220 community-dwelling older adults aged 65 or older with baseline gait speed, followed for disability and mortality. Outcomes were incident inability or dependence on another person in bathing or dressing; and difficulty walking ¼ - ½ mile or climbing 10 steps within 3 years.
  
  
  RESULTS
  Participants with faster baseline gait had lower rates of incident disability. In subgroups (defined by 0.2 m/s-wide intervals from <0.4 to ≥ 1.4 m/s) with increasingly greater gait speed, 3-year rates of bathing or dressing dependence trended from 10% to 1% in men, and from 15% to 1% in women, while mobility difficulty trended from 47% to 4% in men and 40% to 6% in women. The age-adjusted relative risk ratio per 0.1 m/s greater speed for bathing or dressing dependence in men was 0.68 (0.57-0.81) and in women: 0.74 (0.66-0.82); for mobility difficulty, men: 0.75 (0.68-0.82), women: 0.73 (0.67-0.80). Results were similar for combined disability and mortality. Effects were largely consistent across subgroups based on age, gender, race, body mass index, prior hospitalization, and selected chronic conditions. In the presence of multiple other risk factors for disability, gait speed significantly increased the area under the receiver operator characteristic curve.
  
  
  CONCLUSIONS
  In older adults, gait speed predicts 3 year incidence of bathing or dressing dependence, mobility difficulty, and a composite outcome of disability and mortality.
authors: Division of Geriatric Medicine, University of Pittsburgh, Pennsylvania. ksp9@pitt.edu.
authors: Subashan
authors: S
authors: Perera
authors: Department of Anesthesiology and Pain Medicine, University of Washington, Seattle.
authors: Kushang V
authors: KV
authors: Patel
authors: Department of Epidemiology, University of Pittsburgh, Pennsylvania.
authors: Caterina
authors: C
authors: Rosano
authors: Department of Epidemiology and Biostatistics, University of California-San Francisco.
authors: Susan M
authors: SM
authors: Rubin
authors: Department of Preventive Medicine, University of Tennessee Health Science Center, Memphis.
authors: Suzanne
authors: S
authors: Satterfield
authors: Geriatric Epidemiology Section, National Institute on Aging, Bethesda, Maryland.
authors: Tamara
authors: T
authors: Harris
authors: Division of Epidemiology and Community Health, University of Minnesota and Minneapolis VA Health Care System.
authors: Kristine
authors: K
authors: Ensrud
authors: Division of Endocrinology, Diabetes, and Clinical Nutrition, Oregon Health Sciences University, Portland.
authors: Eric
authors: E
authors: Orwoll
authors: Research Service, Veterans Affairs Health Care System, Portland, Oregon.
authors: Christine G
authors: CG
authors: Lee
authors: Department of Pharmacoepidemiology, Merck & Co., Kenilworth, New Jersey.
authors: Julie M
authors: JM
authors: Chandler
authors: Department of Epidemiology, University of Pittsburgh, Pennsylvania.
authors: Anne B
authors: AB
authors: Newman
authors: Department of Epidemiology, University of Pittsburgh, Pennsylvania.
authors: Jane A
authors: JA
authors: Cauley
authors: Department of Epidemiology and Public Health, University of Maryland, College Park.
authors: Jack M
authors: JM
authors: Guralnik
authors: Longitudinal Studies Section, National Institute on Aging, Baltimore, Maryland.
authors: Luigi
authors: L
authors: Ferrucci
authors: Longitudinal Studies Section, National Institute on Aging, Baltimore, Maryland.
authors: Stephanie A
authors: SA
authors: Studenski
mesh_terms: D000203:Activities of Daily Living; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D015331:Cohort Studies; D004185:Disability Evaluation; D006233:Persons with Disabilities / Q000706:statistics & numerical data*; D005260:Female; D005684:Gait / Q000502:physiology*; D015577:Geriatric Assessment; D006801:Humans; D057187:Independent Living / Q000706:statistics & numerical data*; D008297:Male; D051346:Mobility Limitation; D011237:Predictive Value of Tests; D011379:Prognosis; D011597:Psychomotor Performance; D012372:ROC Curve; D018570:Risk Assessment; D012307:Risk Factors; D016019:Survival Analysis; D014481:United States
keywords: Disability; Gait speed; Mobility; Mortality; Performance