1. Department of Metabolic Medicine, Graduate School of Medicine, Osaka University, Osaka, 565-0871, Japan
2. Department of Endocrinology and Metabolism, Sumitomo Hospital, Osaka, 530-0005, Japan
3. Physical Check-up Center, Sumitomo Hospital, Osaka, 530-0005, Japan
4. Department of Internal Medicine (I), Osaka Medical College, Osaka, 569-8686, Japan
5. Department of Diabetes Care Medicine, Graduate School of Medicine, Osaka University, Osaka, 565-0871, Japan