Intermittently scanned continuous glucose monitoring compared with blood glucose monitoring is associated with lower HbA1c and a reduced risk of hospitalisation for diabetes-related complications in adults with type 2 diabetes on insulin therapies

Abstract

Aims/hypothesis: We assessed the impact of initiating intermittently scanned continuous glucose monitoring (isCGM) compared with capillary blood glucose monitoring (BGM) on HbA_1c levels and hospitalisations for diabetes-related complications in adults with insulin-treated type 2 diabetes in Sweden.

Methods: This retrospective comparative cohort study included adults with type 2 diabetes who had a National Diabetes Register initiation date for isCGM after 1 June 2017. Prescribed Drug Register records identified subgroups treated with multiple daily insulin injections (T2D-MDI) or basal insulin (T2D-B), with or without other glucose-lowering drugs. The National Patient Register provided data on hospitalisation rates.

Results: We identified 2876 adults in the T2D-MDI group and 2292 in the T2D-B group with an isCGM index date after 1 June 2017, matched with 33,584 and 43,424 BGM control participants, respectively. The baseline-adjusted difference in the change in mean HbA_1c for isCGM users vs BGM control participants in the T2D-MDI cohort was -3.7 mmol/mol (-0.34%) at 6 months, and this was maintained at 24 months. The baseline-adjusted difference in the change in HbA_1c for isCGM users vs BGM control participants in the T2D-B cohort was -3.5 mmol/mol (-0.32%) at 6 months, and this was also maintained at 24 months. Compared with BGM control participants, isCGM users in the T2D-MDI cohort had a significantly lower RR of admission for severe hypoglycaemia (0.51; 95% CI 0.27, 0.95), stroke (0.54; 95% CI 0.39, 0.73), acute non-fatal myocardial infarction (0.75; 95% CI 0.57, 0.99) or hospitalisation for any reason (0.84; 95% CI 0.77, 0.90). isCGM users in the T2D-B cohort had a lower RR of admission for heart failure (0.63; 95% CI 0.46, 0.87) or hospitalisation for any reason (0.76; 95% CI 0.69, 0.84).

Conclusions/interpretation: This study shows that Swedish adults with type 2 diabetes on insulin who are using isCGM have a significantly reduced HbA_1c and fewer hospital admissions for diabetes-related complications compared with BGM control participants.

Keywords: CGM; Cardiovascular disease; Hospitalisation; Insulin treated; Intermittently scanned; Swedish National Diabetes Register; Swedish National Patient Register; Type 2 diabetes.