Continuous glucose monitoring outperformed self-monitoring of blood glucose for glycaemic control in type 2 diabetes patients on insulin, a large industry-funded RCT has found.

Published in The Lancet Diabetes and Endocrinology, the trial assigned 303 patients 2:1 to CGM or self-monitoring of blood glucose (SMBG). Baseline HbA1c was 8.8% in both groups.

Funded by CGM maker Abbott Diabetes Care, the two-phase study first had patients self-manage with basal insulin titration for 16 weeks, then allowed clinicians to review and add therapies from weeks 17 to 32.

Key results:

CGM users also recorded higher time-in-range, greater device satisfaction and more confidence managing hypoglycaemia.

The study targeted a population “commonly seen in clinical practice”; patients who had not achieved glycaemic targets despite being on contemporary therapies, wrote Associate Professor Emma Wilmot of the University of Nottingham and colleagues.

The between-group HbA1c difference at 16 weeks was achieved without any differences in insulin doses or other medications, suggesting “the glycaemic benefits might have been driven through lifestyle changes,” the authors said.

Once clinicians became involved, patients in the CGM group had four-fold greater clinician-initiated prandial insulin use than the finger-prick group, likely reflecting better recognition of post-prandial glucose excursions through direct glucose visualisation, the authors said.

“Together with previous randomised evidence, findings from this study support the use of CGM for people with type 2 diabetes treated with basal insulin in routine practice,” they wrote.

The trial was open-label, a recognised limitation. Recruitment was also prolonged by a global GLP- shortage that restricted prescribing in the UK during the study period.