Efficacy and safety of continuous and intermittently scanned continuous glucose monitoring in patients with type 2 diabetes: A systematic review and meta-analysis of interventional evidence

Abstract

<p dir="ltr">Background: Traditional diabetes self-monitoring of blood glucose (SMBG), involves inconvenient finger pricks. CGM and isCGM systems offer continuous glucose monitoring, enhancing type 2 diabetes management with convenient, comprehensive data.</p><p dir="ltr">Purpose: To ssess the benefits and potential harms of CGM and intermittently scanned CGM (isCGM) compared to usual care or SMBG in individuals with T2D.</p><p dir="ltr">Data sources: we conducted a comprehensive search of MEDLINE, Embase, The Cochrane library, Web of Science, and bibliographies up to August 2023 </p><p dir="ltr">Study Selection: We analyzed studies meeting these criteria: randomized controlled trials comparing at least two interventions for ≥8 weeks in T2D patients, including CGM in real-time/retrospective mode, short/long-term CGM, isCGM, and SMBG, reporting glycaemic and relevant data.</p><p dir="ltr">Data Extraction: We employed a standardized data collection form, extracting details including author, year, study design, baseline, intervention, and outcomes. </p><p dir="ltr">Data Synthesis: We included 26 RCTs (17 CGM and 9 isCGM) involving 2783 patients with T2D (CGM=632 vs usual care/SMBG=514 and isCGM=871 vs usual care/SMBG=766). CGM reduced HbA1c (MD, 95% CI) by -0.19% (-0.34, -0.04), glycaemic medication effect score [-0.67 (-1.20 to -0.13)], reduced user satisfaction [-0.54 (-0.98, -0.11)] and increased the risk of adverse events [RR of 1.22 (1.01-1.47)]. isCGM reduced HbA1c by -0.31% (-0.46, -0.17), Increased user satisfaction [0.44 (0.29, 0.59)], improved CGM metrics and increased the risk of adverse events [RR 1.30 (.05-1.62)]. Neither CGM nor isCGM had a significant impact on body composition, blood pressure or lipid levels.</p><p dir="ltr">Limitations: limitations include small samples, single-study outcomes, population variations, and uncertainty for younger adults. Additonally, fewer than 10 studies for most endpoints restrict comprehensive analysis and technological advancements over time needs to be considered.</p><p dir="ltr">Conclusions: Both CGM and isCGM demonstrated a reduction in HbA1c levels in individuals with T2D, and unlike CGM, isCGM use was associated with improved user satisfaction The impact of these devices on body composition, blood pressure, and lipid levels remains unclear while both CGM and isCGM use was associated with increased risk of adverse events.</p>