title: Lower extremity function trajectories in the African American Health Cohort.
abstract: BACKGROUND
  We addressed two understudied issues in estimating lower extremity functional trajectories in older adults-incorporating the effect of mortality and evaluating heterogeneity among African Americans.
  
  
  METHODS
  Data were taken from the 998 participants in the African American Health cohort. A highly reliable and valid 8-item lower extremity function scale was used at baseline and at the 1-, 2-, 3-, 4-, 7-, and 9-year follow-up interviews. Semiparametric (ie, discrete) group-based mixture modeling identified the trajectories, and multinomial logistic regression identified risk factors for differential trajectory groups.
  
  
  RESULTS
  When treating mortality as informative censoring, six discrete trajectories were observed with 45% of the participants belonging to three stable trajectories (good, fair, or poor function), and the remainder belonging to three declining trajectories (very high function with minimal improvement then minimal decline, very good function with a slow and modest decline, and very good function with a large and quick decline).
  
  
  CONCLUSIONS
  Substantial heterogeneity in lower extremity function trajectories exists in the African American Health cohort, after appropriately treating mortality as informative censoring.
authors: Department of Health Management and Policy, College of Public Health, The University of Iowa. fredric-wolinsky@uiowa.edu.
authors: Fredric D
authors: FD
authors: Wolinsky
authors: Department of Health Management and Policy, College of Public Health, The University of Iowa.
authors: Padmaja
authors: P
authors: Ayyagari
authors: Department of Neurology & Psychiatry, School of Medicine, Saint Louis University, Missouri.
authors: Theodore K
authors: TK
authors: Malmstrom
authors: Department of Biostatistics, Washington University in St. Louis, Missouri.
authors: J Phillip
authors: JP
authors: Miller
authors: Department of Public Health and Preventive Medicine, Oregon Health & Science University, Portland.
authors: Elena M
authors: EM
authors: Andresen
authors: Department of Epidemiology, School of Public Health, Saint Louis University, Missouri.
authors: Mario
authors: M
authors: Schootman
authors: Center for Aging Research, Indiana University & the Regenstrief Institute, Indianapolis.
authors: Douglas K
authors: DK
authors: Miller
mesh_terms: D001741:Black or African American / Q000706:statistics & numerical data; D000368:Aged; D000375:Aging / Q000502:physiology*; D015897:Comorbidity; D005163:Factor Analysis, Statistical; D005260:Female; D015577:Geriatric Assessment; D006304:Health Status; D006801:Humans; D008019:Life Style; D016015:Logistic Models; D035002:Lower Extremity / Q000502:physiology* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D009026:Mortality; D011594:Psychometrics
keywords: Disablement process; Epidemiology.; Functional performance; Minority aging