Chih-Sung Liang1, Che-Sheng Chu2. 1. Department of Psychiatry, Beitou Branch, Tri-Service General Hospital, Taipei, Taiwan; Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei, Taiwan. 2. Department of Psychiatry, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan; Center for Geriatrics and Gerontology, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan; Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.