1 Aging and Health Research Center, National Yang Ming Chiao Tung University, Taipei, Taiwan; Center for Geriatrics and Gerontology, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan.
2 Aging and Health Research Center, National Yang Ming Chiao Tung University, Taipei, Taiwan; Center for Geriatrics and Gerontology, Taipei Veterans General Hospital, 201, Sec. 2, Shih-Pai Rd., Taipei 11217, Taiwan; Taipei Municipal Gan-Dau Hospital (Managed by Taipei Veterans General Hospital), Taipei, Taiwan. Electronic address: lkchen2@vghtpe.gov.tw.