Longitudinal analysis of bone microstructural changes under luseogliflozin treatment using second-generation High-Resolution peripheral Quantitative Computed Tomography (HR-pQCT) in elderly patients with type 2 diabetes

INTERVENTION: The luseogliflozin group: Administer luseogliflozin 2.5 mg a day orally. Administration of luseogliflozin is increased to 5.0 mg if participants cannot achieve the HbA1c levels less than 7.0 % at each visit of 12, 24, 36 weeks of the study, or a decrease in the HbA1c of more than or equal to 0.5 % compared with those in the previous visit. Maximum dose of luseogliflozin is permitted up to 5.0 mg per day. If participants cannot achieve the HbA1c levels described above, 500 mg of metformin is added in each visit. However, the dosage increase of metformin is permitted by every 250 mg if the participant is already administered metformin more than or equal to 1500 mg per day. Maximum dose of metformin is permitted up to 2250 mg per day. The metformin group: Administer metformin 500 mg a day orally in addition to the baseline regime. Administration of metformin is increased by every 500 mg if participants cannot achieve the HbA1c levels less than 7.0 % at each visit of 12, 24, 36 weeks of the study or a decrease in the HbA1c of more than or equal to 0.5 % compared with those in the previous visit. However, the increase of metformin is permitted by every 250 mg if the participant is already administered metformin more than or equal to 1500 mg per day. Maximum dose of metformin is permitted up to 2250 mg per day. CONDITION: type 2 diabetes PRIMARY OUTCOME: Changes in the predicted bone strength of radius and tibia calculated using HR‐pQCT (kN/mm) SECONDARY OUTCOME: Changes in the values of blood and biochemical tests.; Changes in the bone mineral density at lumbar spine, femur, radius measured by dual‐energy X‐ray absorptiometry.; Incidence of vertebral fracture or femoral fracture.; Changes in the values of bone metabolic markers.; Changes in the values related with cortical bone structure, travecular bone structure or bone morphology calculated using by HR‐pQCT. INCLUSION CRITERIA: