This systematic review of randomised trials found nine studies that investigated whether continuous glucose monitoring (CGM) compared with self-monitoring of blood glucose (SMBG) led to improved glycaemic control or a reduction in hypoglycaemic episodes.
The reviewers combined the results of the study in a meta-analysis to measure the benefit of CGM compared with conventional treatment with SMBG.
Bottom line
Continuous glucose monitoring may improve glycaemic control amongst adult diabetics with poor control. The meta-analysis for type 1 diabetes saw an average reduction in Hba1c of 0.5% (95% confidence interval 0.69% to 0.30%) whilst type 2 diabetes saw an average reduction of 0.70% (95% confidence interval 1.14% to 0.27%).
About the review
- Patients: Diabetes (type 1 and type 2), most with HbA1c >8%.
- Intervention: Continuous glucose monitoring (CGM) compared with Self-Monitoring of Blood Glucose, with at least 8 weeks follow-up
- Outcomes: Glycaemic control (HbA1c) and hypoglycemia
Appraisal tips
Readers of this review are advised to consider the following:
- The individual studies were reported as low to moderate quality. These were small studies and therefore more likely to be subject to bias.
- It seems likely that important differences between individual studies (such patient characteristics, how the interventions were delivered and the duration of follow-up) might undermine the validity of combining them into a single overall measure of beneit.
Reference
The studies varied in the duration and frequency of CGM and SMBG.
Efficacy of continuous glucose monitoring in improving glycemic control and reducing hypoglycemia: a systematic review and meta-analysis of randomized trials.
J Diabetes Sci Technol. 2011;5(4):952-65
Authors: Gandhi GY, Kovalaske M, Kudva Y, Walsh K, Elamin MB, Beers M, Coyle C, Goalen M, Murad MS, Erwin PJ, Corpus J, Montori VM, Murad MH