[1] Binzhou Med Univ, Dept Neurol, Yantai Affiliated Hosp, Yantai 264003, Shandong, Peoples R China
[2] Linglong Yingcheng Hosp, Dept Neurol, Zhaoyuan 265400, Shandong, Peoples R China
[3] Heze Med Coll, Dept Neurol, Affiliated Hosp, Heze 274000, Shandong, Peoples R China
[4] Binzhou Med Univ, Dept Geriatr Med, Yantai Affiliated Hosp, 717 Jinbu St, Yantai 264003, Shandong, Peoples R China