Continuous Glucose Monitoring–Derived Glucose Metrics Over Time in Physically Active Adults Without Diabetes Using a Commercial Continuous Glucose Monitoring Application

Abstract

Background:

To describe changes in continuous glucose monitoring (CGM)-derived glucose metrics of healthy and physically active participants with mild dysglycemia at baseline (>5% time with glucose levels outside of 70-140 mg/dL) who wore a real-time CGM device (GSB, Glucose Sport Biosensor) integrated with a smartphone mobile application over an eight-week period (four GSB wear periods).

Methods:

Two hundred twenty-five participants (51 females and 174 males) aged 45.0 ± 10.1 years with body mass index 23.4 ± 3.9 kg/m² with suboptimal time in tight range (TITR) (ie, <95%) wore a GSB for approximately eight weeks. Linear mixed-effects models (LMEMs) were used to compare the cumulative time in different glycemic zones (% time below range [TBR, <70 mg/dL]; % TITR [70-140 mg/dL]; % time above range [TAR, >140 mg/dL]) with respect to each GSB wear time.

Results:

Linear-mixed effects model analysis returned significant effects of sensor on TITR and TBR across four wear periods (both P < .001), with inter-individual variability in baseline values and response slopes. Each day of sensor wear increased TITR by 0.59% (95% confidence interval [CI]: 0.50, 0.69, P < 0.001) and reduced TBR (−0.42 %, 95% CI: −0.50, −0.35, P <.001) and TAR (−0.17 %, 95% CI: −0.24, −0.10, P < .001), with small sensor-dependent differences in daily improvements.

Conclusions:

These findings indicate both cumulative and day-to-day gains in glucose control with repeated sensor use for individuals with a TITR <95%. Indeed, CGM use coincided with short-term improvements in glucose metrics. Future studies should directly measure lifestyle behaviors to determine which factors may contribute to improvements in glycemia.