The therapeutic efficacy of continuous glucose monitoring in diabetes: an updated meta-analysis with meta-regression

Purpose: Continuous glucose monitoring (CGM) plays a key role for achieving glycemic targets in many people with diabetes. We aim at 1) updating the evidence on the efficacy of CGM and 2) determining which is the contribution of CGM-related metrics to the change of both HbA1c and mean glucose, providing a meta-analysis with meta-regression of randomized controlled trials (RCT). Methods: Electronic database were searched until 20 December 2024. We included RCTs reporting both HbA1c and mean CGM glucose together with time in range (TIR), time above range (TAR) and time below range (TBR). Two investigators extracted data from each study. A random effect model was used to calculate the pooled weighted mean difference (WMD) with the 95% CI. Results: The meta-analysis included 19 studies involving 2936 patients. Compared with control strategies, CGM led to a reduction of both HbA1c (WMD -0.18%, 95% CI -0.28 to -0.08, P<0.001) and mean glucose (-5.07 mg/dL, 95% CI –8.46 to –1.68, P = 0.003), and improvement of TIR, TAR and TBR. In meta-regression, there was a significant association between the change in both HbA1c and mean glucose and TIR (beta = - 0.046, P <0.001 and beta = -1.98, P <0.001, respectively) and TAR (beta = 0.047, P<0.001 and beta = 1.69, P <0.001), that explained 100% of between-study variance. Conclusion: CGM improve glucose control in diabetes. The change of TAR is the best contributor to the improvement of glucose control.