The Association of British Clinical Endocrinologists (ABCD) began its UK-wide audit of FreeStyle Libre users in November 2017, after the flash glucose monitoring device was made available on the NHS Drug Tariff. Data have been recorded during routine clinical care. Out of 10 370 individuals from 102 NHS hospitals who had baseline data submitted (97% of whom had type 1 diabetes), follow-up data are now available for 3182 in total.
Mean HbA1c across the study cohort fell from 68 to 62 mmol/mol (8.3% to 7.9%) over the follow-up. Reductions were greater in those with a higher baseline HbA1c. Higher baseline HbA1c and a higher number of scans per day were significant predictors of greater HbA1c reduction. In contrast, age, sex, BMI, structured diabetes education completion and duration of diabetes did not significantly affect HbA1c reduction.
Mean Gold score fell significantly from 2.7 to 2.4 (indicating greater hypoglycaemia awareness). Of those participants with a baseline score of ≥4 (indicating hypo unawareness), 53% reported a score of <4 (indicating restored awareness) at follow-up. Mean diabetes distress scores also fell over the follow-up.
Comparing the 12 months prior to Libre initiation with a median of 7.5 months post-initiation (data available from around 2000 participants for each comparison), the total number of paramedic call-outs fell from 275 to 38. Hospital admissions due to hyperglycaemia or diabetic ketoacidosis fell from 269 to 86, and those due to hypoglycaemia fell from 120 to 45. The total number of episodes of severe hypoglycaemia (requiring third-party assistance) fell from 1032 to 237.
Side-effects, including itching, redness, rash, allergic reaction or bleeding, occurred in 4% of users, and 7% had technical issues concerning either the sensor or the reader.
The authors conclude that, in this large, real-world data set, use of the FreeStyle Libre was associated with significant improvements in glycaemic control, hypoglycaemia awareness, severe hypoglycaemia and hospital admissions. Longer-term follow-up and cost analyses are needed to assess whether these benefits are sustained and affordable to healthcare systems.
Deshmukh H, Wilmot EG, Gregory R et al (2020) Effect of flash glucose monitoring on glycemic control, hypoglycemia, diabetes-related distress, and resource utilization in the Association of British Clinical Diabetologists (ABCD) nationwide audit. Diabetes Care 15 Jul [epub ahead of print]. https://doi.org/10.2337/dc20-0738