[1] Chonnam Natl Univ, Bitgoeul Hosp, Dept Internal Med, 80 Deoknam gil, Gwangju 61748, South Korea
[2] Univ Ulsan, Coll Med, Dept Internal Med, Asan Med Ctr,Div Geriatr, 88 Olympic ro 43-gil, Seoul 05505, South Korea
[3] Univ Ulsan, Coll Med, Asan Med Ctr, Dept Rehabil Med, Seoul, South Korea
[4] Asan Med Ctr, Dept Nursing, Seoul, South Korea