1. Department of Health Sciences Research (S.M.M., A.M.C., S.A.W., R.J., V.L.R.)
2. Division of Geriatric Medicine and Gerontology, Johns Hopkins University, Baltimore, MD (C.M.B.).
3. Department of Hospital Internal Medicine (D.M.M.)
4. Division of Cardiovascular Diseases (K.L.P., A.C., E.E.K., V.L.R.)
5. Division of Physical Medicine and Rehabilitation (K.L.P., A.C., E.E.K., V.L.R.), Mayo Clinic, Rochester, MN.