[1] China Acad Chinese Med Sci, Xiyuan Hosp, Dept Neurol, Beijing 100091, Peoples R China
[2] China Populat & Dev Res Ctr, Beijing 100081, Peoples R China
[3] Peking Univ, Dept Inst Populat Res, Beijing 100087, Peoples R China
[4] China Acad Chinese Med Sci, Grad Sch, Beijing 100700, Peoples R China
[5] Beijing Univ Chinese Med, Grad Sch, Beijing 100029, Peoples R China