1. Department of Diabetes and Metabolic Medicine, National Center for Global Health and Medicine, Tokyo 162-8655, Japan
2. Department of Endocrinology and Metabolism, Yokohama City University Graduate School of Medicine, Yokohama 236-0004, Japan
3. National Institute of Health and Nutrition, Tokyo 162-8636, Japan
4. Japan Foundation for the Promotion of International Medical Research Cooperation, Tokyo 162-0052, Japan
5. Otsuka Pharmaceutical Co. Ltd., Tokushima 771-0182, Japan
6. Department of Epidemiology and International Health, Research Institute, National Center for Global Health and Medicine, Tokyo 162-8655, Japan