Authors' objectives: The appraisal aimed to identify and summarise evidence that addresses the following question: What is the clinical and cost effectiveness of flash glucose monitoring in people with diabetes? This is an updated version of an appraisal. HTW originally issued Guidance on this topic in November 2018.

Authors' results and conclusions: This rapid review used evidence from randomised controlled trials (RCTs), existing evidence reviews, and non-randomised trials if limited outcome data from RCTs was available. Seven RCTs compared flash glucose monitoring to self-monitoring of blood glucose (SMBG) in people with type 1 or type 2 diabetes, the majority of whom were treated with insulin. All of the studies used the Freestyle Libre device (either Freestyle Libre or Freestyle Libre 2) and it was noted that the functionality of these two device iterations in terms of blood glucose measurement and monitoring is not significantly different. Overall, the results suggest Freestyle Libre flash glucose monitoring (FLFGM) is beneficial in terms of improving time spent in target glucose range (and thus avoiding episodes or hypo- or hyperglycaemia), although it should be noted that not all trials found conclusive evidence of a difference between the two interventions. The evidence also suggests people who use FLFGM are able to check their glucose more frequently by scanning the device than those who use SMBG. For other outcomes (glycosylated haemoglobin levels, quality of life, and device-related adverse events) there was no convincing evidence of a difference between FLFGM and SMBG. Large-scale audits of real-world evidence suggest a reduction in paramedic callouts, hospital admissions, visits to diabetes/endocrine specialists and primary care visits following initiation of FLFGM over follow up times of 7.5 to 14 months. However, this evidence is of lower certainty than the evidence derived from RCTs. Evidence from three cost-utility analyses identified in the literature showed the potential for FLFGM to be cost-effective in cost per quality-adjusted life years (QALY) terms. However, there was uncertainty around key assumptions in the analyses, such as the inclusion of a process-related improvement in quality of life associated with using flash glucose monitoring. A cost-utility analysis developed by HTW aimed to provide a more conservative estimate of the cost-effectiveness of FLFGM since it was based only on reductions in non-severe hypoglycaemic events and SMBG usage. The results suggest that FLFGM is a cost-effective intervention compared to usual care with incremental cost-effectiveness ratios (ICERs) of £4,706 and £13,137 per QALY for type 1 and type 2 diabetes, respectively. Sensitivity analysis showed that the key areas of uncertainty were the baseline SMBG testing frequency and the quality of life benefits associated with reducing non-severe hypoglycaemic events. The appropriate mechanism for patient engagement was determined and the patient perspective was considered where possible. A written patient submission from Diabetes UK Cymru was included in the appraisal. A literature search was also undertaken to report experiences, perspectives, and opinions of patients with this condition and their experiences of blood glucose monitoring.

Authors' recommendations: The evidence supports the routine adoption of Freestyle Libre flash glucose monitoring to guide blood glucose regulation in people with diabetes who require treatment with insulin. The use of Freestyle Libre flash glucose monitoring in these people improves the proportion of time that the blood glucose is in target range and reduces time in hypo- and hyperglycaemia. Health economic modelling indicates that the use of Freestyle Libre flash glucose monitoring is a cost-effective intervention compared to finger-prick self-monitoring of blood glucose with incremental cost-effectiveness ratios (ICERs) of £4,706 and £13,137 per QALY for type 1 and type 2 diabetes, respectively.

Authors' methods: The Evidence Appraisal Report is based on a literature search (strategy available on request) for published clinical and economic evidence on the health technology of interest. It is not a full systematic review but aims to identify the best available evidence on the health technology of interest. Researchers critically evaluate and synthesise this evidence. We include the following clinical evidence in order of priority: systematic reviews; randomised trials; non-randomised trials. We only include evidence for “lower priority” evidence where outcomes are not reported by a “higher priority” source. We also search for economic evaluations or original research that can form the basis of an assessment of costs/cost comparison. We carry out various levels of economic evaluation, according to the evidence that is available to inform this.

Project Status: Completed

Year Published: 2021

URL for published report: https://www.healthtechnology.wales/reports-guidance/freestyle-libre-flash-glucose-monitoring/

English language abstract: An English language summary is available

Publication Type: Rapid Review

Country: Wales, United Kingdom

Organisation Name: Health Technology Wales

Contact Address: Floor 3, 2 Capital Quarter, Tyndall Street, Cardiff, CF10 4BZ

Contact Name: Susan Myles, PhD

Contact Email: healthtechnology@wales.nhs.uk