Center for Innovative Clinical Medicine, Okayama University Hospital, Okayama, Japan. Division of Metabolism and Biosystemic Science, Department of Medicine, Asahikawa Medical University, Asahikawa, Japan. Department of Epidemiology and Public Health, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan. Department of Diabetology & Endocrinology, Kanazawa Medical University, Ishikawa, Japan. Health Administration Center, Niigata University, Niigata, Japan. Suzuki Diabetes Clinic, Kanagawa, Japan. Research Center for Health Care, Nagahama City Hospital, Shiga, Japan. Division of Metabolism and Diabetes, Tohoku Medical and Pharmaceutical University, Sendai, Japan. Division of Nephrology, Department of Internal Medicine, Juntendo University Faculty of Medicine, Tokyo, Japan. Division of Nephrology, Department of Medicine, Nippon Life Hospital, Osaka, Japan. Department of Diabetes and Endocrinology, National Hospital Organization Chiba-East National Hospital, Chiba, Japan. Department of Advanced Genomic and Laboratory Medicine, Graduate School of Medicine, University of the Ryukyus, Okinawa, Japan. Division of Clinical Laboratory and Blood Transfusion, University of the Ryukyus Hospital, Okinawa, Japan. Okayama Diabetes and Neurology Clinic, Okayama, Japan. Okayama University, Okayama, Japan.