Department of Neurology, Xijing Hospital, Fourth Military Medical University, Xi'an, China. Department of Neurology, Xijing Hospital, Fourth Military Medical University, Xi'an, China; Department of Neurology, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China. Department of Neurology, The PLA 940 Hospital, Lanzhou, China; Department of Neurology, Gansu Provincial Central Hospital, Lanzhou, China. Department of Neurology, Xi'an No.3 Hospital, Xi'an, China. Department of Neurology, Tangdu Hospital, Fourth Military Medical University, Xi'an, China. Department of Neurology, The First Affiliated Hospital of Xi'an Medical University, Xi'an, China. Department of Neurology, The First People's Hospital of Xianyang, Xianyang, China. Department of Neurology, Xi'an Gaoxing Hospital, Xi'an, China. Department of Neurology, Yulin No 1 Hospital, Yulin, China. Department of Neurology, General Hospital of Xinjiang Military Command, Urumqi, China. Department of Neurology, Tongchuan People's Hospital, Tongchuan, China. Department of Neurology, Tongchuan Mining Bureau Hospital, Tongchuan, China. Department of Neurology, Xi'an Central Hospital, Xi'an, China. Department of Health Statistics, Fourth Military Medical University, Xi'an, China. Department of Neurology, Xijing Hospital, Fourth Military Medical University, Xi'an, China; The Shaanxi Cerebrovascular Disease Clinical Research Centre, Xi'an, China. Electronic address: fyangx_neuro@163.com. Department of Neurology, Xijing Hospital, Fourth Military Medical University, Xi'an, China; The Shaanxi Cerebrovascular Disease Clinical Research Centre, Xi'an, China. Electronic address: jiangwen@fmmu.edu.cn.