1. First Department of Internal Medicine, School of Medicine, University of Occupational and Environmental Health, Japan, Kitakyushu, Japan.
2. Clinical Research Center, Hospital of the University of Occupational and Environmental Health, Japan, Kitakyushu, Japan.
3. Department of Metabolism and Endocrinology, Juntendo University Graduate School of Medicine, Tokyo, Japan.
4. Department of Metabolic Medicine, Osaka University Graduate School of Medicine, Osaka, Japan.
5. Department of Metabolism and Atherosclerosis, Osaka University Graduate School of Medicine, Osaka, Japan.
6. Department of Medicine, Diabetology and Endocrinology, Juntendo Tokyo Koto Geriatric Medical Center, Tokyo, Japan.
7. Department of Internal Medicine, Ashiya Central Hospital, Fukuoka, Japan.
8. Nishida Keiko Diabetes Clinic, Kitakyushu, Japan.
9. Inokuchi Internal Medicine Clinic, Kitakyushu, Japan.
10. Department of Biostatistics, Faculty of Medicine, University of Tsukuba, Ibaraki, Japan.