1. Department of Anesthesiology, Taichung Veterans General Hospital, Taichung 407219, Taiwan
2. Division of Endocrinology and Metabolism, Department of Internal Medicine, Taichung Veterans General Hospital, Taichung 407219, Taiwan
3. Department of Post-Baccalaureate Medicine, College of Medicine, National Chung Hsing University, Taichung 402202, Taiwan
4. Department of Medicine, School of Medicine, National Yang Ming Chiao Tung University, Taipei 112304, Taiwan