1. Department of Medicine and Bioregulatory Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan
2. Division of Hepatology, Diabetes, Metabolism and Endocrinology, Saga Medical School, Saga 849-8501, Japan
3. Department of Endocrinology and Diabetes Mellitus, School of Medicine, Fukuoka University, Fukuoka 814-0180, Japan
4. Department of Geriatric Medicine, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan