Continuous Glucose Monitoring Profiles in Healthy Nondiabetic Participants: A Multicenter Prospective Study

CONTEXT: Use of continuous glucose monitoring (CGM) is increasing for insulin-requiring patients with diabetes. Although data on glycemic profiles of healthy, nondiabetic individuals exist for older sensors, assessment of glycemic metrics with new-generation CGM devices is lacking. OBJECTIVE: To establish reference sensor glucose ranges in healthy, nondiabetic individuals across different age groups using a current generation CGM sensor. DESIGN: Multicenter, prospective study. SETTING: Twelve centers within the T1D Exchange Clinic Network. PATIENTS OR PARTICIPANTS: Nonpregnant, healthy, nondiabetic children and adults (age ≥6 years) with nonobese body mass index. INTERVENTION: Each participant wore a blinded Dexcom G6 CGM, with once-daily calibration, for up to 10 days. MAIN OUTCOME MEASURES: CGM metrics of mean glucose, hyperglycemia, hypoglycemia, and glycemic variability. RESULTS: A total of 153 participants (age 7 to 80 years) were included in the analyses. Mean average glucose was 98 to 99 mg/dL (5.4 to 5.5 mmol/L) for all age groups except those over 60 years, in whom mean average glucose was 104 mg/dL (5.8 mmol/L). The median time between 70 to 140 mg/dL (3.9 to 7.8 mmol/L) was 96% (interquartile range, 93 to 98). Mean within-individual coefficient of variation was 17 ± 3%. Median time spent with glucose levels >140 mg/dL was 2.1% (30 min/d), and median time spent with glucose levels <70 mg/dL (3.9 mmol/L) was 1.1% (15 min/d). CONCLUSION: By assessing across age groups in a healthy, nondiabetic population, normative sensor glucose data have been derived and will be useful as a benchmark for future research studies.