Physical Frailty in Urban African-Americans

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DESCRIPTION (provided by applicant): This revised competitive renewal of "Physical Frailty in Urban African Americans" requests five years of funding (Y11-15) to enable additional data collection on and analysis of a representative cohort of community-dwelling African Americans living in St. Louis, known as the African American Health (AAH) project. The 998 enrolled AAH subjects were 49 to 65 years of age at baseline evaluation in 2000-2001, 463 from a very poor inner-city area and 535 from more affluent suburban conditions; 865 are alive and continue to participate. Five annual waves of high quality participation and data have already been collected by an experienced team that has made valuable contributions to the field. In the continuation, we propose to obtain telephone interviews (lasting 50 and 25 minutes, respectively) seven and eight years after baseline and a detailed in-home evaluation (120 minutes) nine years after baseline. We expand prior research themes by adding a comprehensive, innovative approach to examining contextual effects, extensive investigations of resilience, and cutting-edge analytic methods. With the combined eight waves of data over ten years, we will pursue two specific aims: (1) investigate the process of disablement in this cohort using individual-level data and (2) investigate the independent effect of adverse neighborhood conditions on the disablement process. We hypothesize that the disablement process can be viewed as an ordered progression in which the principal transitions for 25 tasks are from high functioning (HF), to subclinical status (SC; defined as no reported difficulty but change in either method or frequency of performance), from SC to difficulty (D), and from D to adverse health outcomes (e.g., falls, death). Primary analytic methods involve (a) multi-state transition models for individual tasks and (b) mixed effect models with both fixed and random intercepts and coefficients for three psychometrically-sound composite measures, examining the composite HF, SC, and D count trajectories both individually and simultaneously. For aim 2, our primary hypotheses are: (a) adverse neighborhood conditions (built environment less conducive to physical activity, lower availability of services, and increased area-level deprivation) are associated with disability outcomes, after adjusting for individual- level factors; (b) the negative effect of service availability operates at a different spatial scale than those of the built environment and deprivation; and, (c) adverse neighborhood conditions can be used to target future interventions to improve disability outcomes. Both aims examine recovery as well as deterioration and the effects of hypothesized risk (e.g., obesity) and protective (e.g., education) factors on disability outcomes. Analysis involves multilevel and novel geostatistical techniques. We have experience with all proposed assessment and analytic methods, which have adequate (> 80%) power to detect small to moderate effects for all hypotheses. Multiple secondary studies (e.g., fear of falling, life space mobility) will also be pursued.