Aims

Although conventional interventions for people at high risk of developing type 2 diabetes are usually conducted face-to-face, such interventions are burdensome for healthcare providers. We developed a lifestyle intervention program combining lifestyle coaching via a smartphone application augmented by intermittently scanned continuous glucose monitoring (isCGM) without burdening healthcare providers. Its effectiveness for glycemic control and body weight reduction in people at risk of type 2 diabetes was investigated.

Materials And Methods

For this 12-week randomized unblinded trial with offline recruitment, participants with HbA1c 5.6-6.4% or fasting blood glucose 110-125 mg/dl and body mass index (BMI) > 23 kg/m2 but <40 kg/m2 were randomly assigned to the Intervention group (App) and Control group (C). Primary endpoint was the difference in time in range (TIR) of blood glucose 70-140 mg/dL (3.9-7.8 mmol/L) before and after the study period between the two groups.

Results

Among 168 patients (mean age 48.1 y, mean BMI 26.6 kg/m2, and male 80.4%), 82 and 86 were assigned to the App group and C group, respectively. After 12 weeks, TIR of blood glucose 70-140 mg/dL significantly improved in the App group compared to the C group (-2.6 min/day vs. + 31.5 min/day, p = 0.03). Changes in time above range did not differ, whereas time below range (blood glucose <70 mg/dL;  + 23.5 min/day vs. -8.9 min/day, p = 0.02) improved in the App group. BMI (-0.26 vs. -0.59, p = 0.017) was reduced in the App group compared to the C group.

Conclusion

Intervention with a smartphone app and isCGM increased glycemic control accompanied by decreased carbohydrate intake and weight loss. Further trials are needed to confirm whether these interventions can reduce incident type 2 diabetes.