Association between scanning frequency of flash glucose monitoring and continuous glucose monitoring-derived glycemic makers in children and adolescents with type 1 diabetes

Background We assessed the association between scanning frequency of flash glucose monitoring (FGM) and continuous glucose monitoring (CGM)-derived glycemic markers in children and adolescents with type 1 diabetes. Methods Subjects consisted of 85 children and adolescents with type 1 diabetes using FGM. We assessed the association between scanning frequencies of FGM- and CGM-derived metrics: Time in range (TIR) (70-180 mg/dL), time below range (TBR) (<70 mg/dL), time above range (>180 mg/dL), and other glycemic markers - laboratory-measured HbA1c and CGM-estimated glucose and HbA1c (eA1c) levels in the subjects. Results The mean number of scans was 11.5 +/- 3.5 (5-20) times per day, and scanning was most frequently conducted during a period of 18-24 h. Scanning frequency showed significant positive correlation with TIR (r = 0.719, P < 0.0001) and inverse correlation with time above range (r = -0.743, P < 0.0001), but did not correlate with TBR. There were also significant inverse correlations between scanning frequency and glucose, HbA1c, and eA1c levels (r = -0.765, -0.815, and -0.793, respectively, P < 0.0001). Conclusions Frequent glucose testing with FGM decreased hyperglycemia with increased TIR, but did not reduce TBR. Coping with a rapid fall of glucose and unexpected hypoglycemia with more advanced technology might contribute to a reduction in TBR.