1. Division of Endoscopy, Hirosaki University Hospital, Hirosaki 036-8563, Japan
2. Aomori General Health Examination Center, Aomori 030-0962, Japan
3. Department of Gastroenterology and Hematology, Hirosaki University Graduate School of Medicine, Hirosaki 036-8562, Japan
4. Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, Hirosaki 036-8562, Japan
5. Center of Healthy Aging Innovation, Hirosaki University Graduate School of Medicine, Hirosaki 036-8562, Japan