1. From the Department of Neurology, College of Physicians and Surgeons (H.W., B.B.-A., M.S.V.E., C.B.W., T.R., R.L.S.), Gertrude H. Sergievsky Center (R.L.S., M.S.V.E.), Department of Epidemiology (R.L.S.), Department of Sociomedical Science (B.B.-A.), and Department of Biostatistics (C.W.), Joseph Mailman School of Public Health, Columbia University.