[1] Johns Hopkins Univ, Sch Med, Dept Psychiat & Behav Sci, Baltimore, MD 21224 USA
[2] Johns Hopkins Univ, Sch Med, Div Pulm & Crit Care Med, Dept Med, Baltimore, MD 21224 USA
[3] Johns Hopkins Univ, Sch Med, Dept Phys Med & Rehabil, Baltimore, MD 21224 USA
[4] Sichuan Univ, West China Hosp, Dept Geriatr, Chengdu 610064, Sichuan Provinc, Peoples R China
[5] Univ Colorado, Sch Med, Dept Surg, Aurora, CO USA
[6] Harvard Univ, Sch Med, Beth Israel Deaconess Med Ctr, Dept Med, Boston, MA USA
[7] Hebrew Senior Life, Inst Aging Res, Boston, MA USA