1. Division of Family Medicine, Department of Family and Community Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei 11490, Taiwan
2. Division of Internal Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei 11490, Taiwan
3. Department of Internal Medicine, Taipei Veterans General Hospital, Taipei 11217, Taiwan
4. Faculty of Medicine, National Yang Ming Chiao Tung University, Taipei 11221, Taiwan
5. Division of Geriatric Medicine, Department of Family and Community Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei 11490, Taiwan
6. Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei 11490, Taiwan
7. Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taipei 11490, Taiwan