1. Department of Medicine, Seoul National University College of Medicine, Seoul, Korea.
2. Department of Family Medicine, Seoul National University Health Service Center, Seoul, Korea.
3. Department of Internal Medicine, Seoul National University Boramae Medical Center, Seoul, Korea.
4. Department of Family Medicine and Health Promotion Center, Seoul National University Hospital, Seoul, Korea.
5. Advanced Institutes of Convergence Technology, Seoul National University, Seoul, Korea.
6. Institute on Aging, Seoul National University College of Medicine, Seoul, Korea.