Abbott FreeStyle Libre Versus Dexcom G6: Detecting Disorders of Carbohydrate Metabolism in a Youthful Non-Diabetic Cohort Pilot Study

Objective: Disorders of aging develop decades prior to emerging according to evidence in the literature. Early detection and actionable intervention have tremendous potential to prevent, delay, or even reverse the onset of disease. Individual carbohydrate metabolism data inform interventions to address the progression of underlying disorders of carbohydrate metabolism. Continuous glucose monitoring (CGM) devices can be harnessed to reveal suboptimal glycemic control. In the present study, two CGM devices were used to screen for carbohydrate metabolic dysfunction in 14 individuals without a history of type 2 diabetes. Methods: The two CGM devices used in this prospective cohort study were the Abbott FreeStyle Libre and Dexcom G6. Participants concurrently wore both devices for 30 days and were instructed to maintain their usual dietary habits for the duration of the study. The optimal glucose range was defined as 70–120 mg/dL. Glucose data were compiled and analyzed to screen for metabolic abnormalities. Results: 14 non-diabetic individuals were enrolled in this study. The cohort was 50% female with ages ranging from 22–46 years (mean=31.4 years). Out of the 14 participants, 100% showed glycemic abnormalities, including hypoglycemia and hyperglycemia. Across the cohort, the Abbott FreeStyle Libre and Dexcom G6 detected fasting and postprandial values between 40–237 mg/dL and 40–279 mg/dL, respectively. Both CGM devices detected glucose values <70 mg/dL and >120 mg/dL in all 14 participants. The amount of time each participant spent outside the optimal glucose range was variable. Using the Abbott FreeStyle Libre, the mean percent of time that participant glucose values measured <70 mg/dL and >120 mg/dL were 9.1% and 4.8%, respectively. Using the Dexcom G6, the mean percent of time that participant glucose values measured <70 mg/dL and >120 mg/dL were 1.4% and 19.2%, respectively. Discussion: Using CGM devices, we discovered that these 14 non-diabetic individuals exhibit suboptimal glycemic control, as demonstrated by blood glucose measurements falling outside 70–120 mg/dL for all participants. In addition, the Abbott FreeStyle Libre detected fasting hypoglycemia and reactive hypoglycemic responses more often than the Dexcom G6, while the Dexcom G6 detected more postprandial hyperglycemia than the Abbott FreeStyle Libre. It is plausible that the recommended device placement contributed to these differences, with the Abbott FreeStyle Libre on the tricep and Dexcom G6 on the abdomen. These findings support the utility of CGM devices as screening tools to detect and predict disorders of carbohydrate metabolism and warrant further investigation into the variation between CGM device measurements.