Benefits of the addition of continuous or flash glucose monitoring versus standard practice using self-monitored blood glucose and haemoglobin A1c in the primary care of diabetes mellitus: a systematic review protocol

INTRODUCTION: Studies demonstrate that optimal glycaemic control reduces morbidity from diabetes mellitus but remains elusive in a significant portion of patients. Although research shows that continuous glucose monitoring (CGM) and flash glucose monitoring (FGM) improves glycaemic control in selected subsets of patients with diabetes in specialty practices, we found no systematic reviews evaluating the use of CGM/FGM in primary care, where the majority of patients with diabetes are cared for. This systematic review aims to answer the questions: ‘compared with usual care of self-monitoring blood glucose and haemoglobin A1c (HbA1c), does the addition of CGM/FGM use in the primary care of patients with diabetes improve glycaemic control, decrease rates of hypoglycaemia, and improve patient and physician satisfaction?’ and if so, ‘what subgroups of primary care patients with diabetes are most likely to benefit?’. METHODS AND ANALYSIS: Aligning with the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols guidelines, a search will be conducted in PubMed, EMBASE, Scopus, CINAHL, Cochrane Central Register of Controlled Trials and Web of Science. We will include studies investigating CGM/FGM use and reporting the primary outcome measure of HbA1c and secondary outcome measures of hypoglycaemia, time in range, time below range, time above range and patient/staff satisfaction. We will examine which patient populations appear to benefit from CGM/FGM. Three independent researchers will use the Covidence systematic review software for blinded screening and study selection. The National Heart, Lung, and Blood Institute quality assessment tool and Grading of Recommendations Assessment, Development and Evaluation will be used to assess the risk of bias and quality of evidence. ETHICS AND DISSEMINATION: The systematic review methodology does not require ethics approval due to the nature of the study design. Study findings will be publicly available to a wide readership across disciplines and will be published in a peer-reviewed journal. PROSPERO REGISTRATION NUMBER: CRD42021229416.