1. Department of Geriatrics, the Third Affiliated Hospital of Qiqihar Medical University, Qiqihar, China
2. Department of Cardiology, the Third Affiliated Hospital of Qiqihar Medical University, Qiqihar, China
3. Department of Neurology, the Third Affiliated Hospital of Qiqihar Medical University, Qiqihar, China
4. School of Nursing, Qiqihar Medical University, Qiqihar, China