1 Department of Physical Medicine and Rehabilitation, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
2 Department of Anesthesiology, Kaohsiung Veterans General Hospital, Pingtung Branch, Pingtung, Taiwan.
3 Institute of Gerontology, College of Medicine, National Cheng Kung University, Tainan, Taiwan.