Continuous and Flash Glucose Monitoring in Adults at Risk of Type 2 Diabetes: A Scoping Review

Background: Continuous glucose monitoring (CGM) and flash glucose monitoring (FGM) are widely used in diabetes management and increasingly being considered for type 2 diabetes mellitus (T2DM) prevention. This scoping review aims to summarize the literature published to date on CGM and FGM use in adults at risk of T2DM.Methods: A systematic search of four databases (CINAHL, PsycINFO, MEDLINE, Cochrane Library) was conducted, covering studies from 1985 to 2024. Eligible studies used CGM or FGM in interventional settings targeting adults at risk of T2DM. Rayyan software facilitated article screening, and the Johns Hopkins Evidence-Based Practice tool assessed study quality.Results: From 13 644 articles, 12 studies were included, reporting on 1144 participants (353 at-risk, mean age 47 +/- 12.8 years) across eight countries. Ten studies employed FGM, focusing on health-related behaviors (diet, physical activity, or both). Significant improvements in glucose control and anthropometrics were reported in 75% and 50% of the studies, respectively, along with reductions in glycated hemoglobin, fasting glucose, and insulin resistance. Seven studies used qualitative methods, with recurrent themes including perceived benefits and motivators for behavior change and acceptability and feasibility of device use. Three studies were rated as "high" level and scored a "B" for evidence quality, while the remaining studies were lower for both level and evidence quality.Conclusions: Existing published studies deploying glucose monitoring technologies show promise in supporting interventions aimed at preventing T2DM in at-risk adults. Further robust studies are required to confirm the long-term acceptability and efficacy of these technologies.