Relationship Among A1C, Hypoglycemia, and Hyperglycemia in Japanese with Type 2 Diabetes—Results from Continuous Glucose Monitoring Data

The intensive treatment aimed at achieving optimal A1C may increase a risk of hypoglycemia. Therefore, we examined the rate and duration of hypoglycemia (70 mg/dL) and the duration of hyperglycemia (≥200 mg/dL) according to their A1C status, using continuous glucose monitoring (CGM) in Japanese patients with type 2 diabetes who were treated with hypoglycemic agents.Forty subjects were equally divided into three groups according to their A1C levels (low, intermediate, and high A1C groups). The 24-h CGM data were collected immediately upon admission to hospital with the patients continuing to take the same medications they had prior to hospitalization.There was a significant difference in the total duration of hyperglycemia among the groups, with the low A1C group having a median duration of hyperglycemia of 50 min (25-75(th) percentile, 0-550 min) compared with 302.5 min (220-500 min) in the intermediate A1C group and 660 min (185-830 min) in the high A1C group. However, the incidence rate and total duration of hypoglycemia were similar for all A1C groups.The A1C level did not predict the presence or the duration of hypoglycemia.