Relationships between time in range, glycemic variability including hypoglycemia and types of diabetes therapy in Japanese patients with type 2 diabetes mellitus: Hyogo Diabetes Hypoglycemia Cognition Complications study

Aims/Introduction Continuous glucose monitoring (CGM) metrics, such as times in range (TIR) and time below range, have been shown to be useful as clinical targets that complement glycated hemoglobin (HbA1c) for patients with type 2 diabetes mellitus. We investigated the relationships between TIR, glycemic variability and patient characteristics in patients with type 2 diabetes mellitus. Materials and Methods We carried out continuous glucose monitoring in 281 outpatients with type 2 diabetes mellitus who participated in a multicenter cohort (Hyogo Diabetes Hypoglycemia Cognition Complications) study. Results The results are shown as the median (interquartile range). The age, disease duration and HbA1c were 68 years (62–71 years), 13 years (7–23 years) and 6.9% (6.5–7.5%), respectively. TIR and standard deviation obtained by continuous glucose monitoring worsened significantly with increasing disease duration. Multiple regression analyses showed that disease duration (standard partial regression coefficient, β  = −0.160, P  = 0.003), diabetic peripheral neuropathy ( β  = −0.106, P  = 0.033) and urinary albumin excretion ( β  = −0.100, P  = 0.043) were useful explanatory factors for TIR. In contrast, HbA1c ( β  = −0.398, P  < 0.001) and the use of antidiabetic drugs potentially associated with severe hypoglycemia ( β  = 0.180, P  = 0.028), such as sulfonylureas, glinides and insulin, were useful explanatory factors for time below range in the elderly patients with type 2 diabetes mellitus. Conclusions The results of this study suggest that disease duration and diabetic complications are associated with TIR deterioration. In addition, low HbA1c levels and the use of antidiabetic drugs potentially associated with severe hypoglycemia might worsen the time below range in the elderly.