[1] Wake Forest Sch Med, Dept Internal Med, Winston Salem, NC 27101 USA
[2] Wake Forest Sch Med, Sect Gerontol & Geriatr Med, Dept Epidemiol & Prevent, Winston Salem, NC 27101 USA
[3] Emory Univ, Dept Med, Sch Med, Dept Neurol, Atlanta, GA 30322 USA
[4] Emory Univ, Dept Med, Sch Med, Div Gen Med & Geriatr, Atlanta, GA 30322 USA