This is a Midcareer Investigator Award in aging-related patient-oriented research. The overarching aims of this proposal are to identify cognitive trajectories, their predictors and outcomes among elders in their 9th and 10 decade of life. We propose to conduct our aims from two ongoing NIH-funded prospective studies, the Study of Osteoporotic Fractures (SOF) and the Health Aging and Body Composition Study (Health ABC). We will determine the 10- to 20-year longitudinal trajectories of cognitive function of elders living into their 80's and 90's and to identify the predictors, primarily novel biomarkers, of these cognitive trajectories. In addition, we will determine how these different trajectories influence important health outcomes such as functional status, mortality and nursing home placement. This award will be instrumental in advancing the applicant's research in the epidemiology of cognitive aging and in mentoring the "next generation" of investigators committed to cognitive aging patient-oriented research.