907-P: Striking Improvements in HbA1c following Commencement of Flash Glucose Monitoring in Type 1 Diabetes

Abstract

Little evidence currently supports the efficacy of Flash Monitoring (FM) in type 1 diabetes. We present the largest prospective study of clinical outcomes following FM. National Health Service (NHS) funding for FM was introduced in Feb 2018 in our center. We evaluated outcomes in 900 people with T1DM. Baseline HbA1c was the most recent value prior to commencing FM. Control HbA1c data were obtained from 518 people with no prior or current FM use. Pre- and post-FM hypoglycemia and Hospital Anxiety and Depression Scale (HADS) data were available in 57%. Hospital admission and test-strip prescription data were obtained for the 6 months following NHS-funding and the corresponding period the previous year. Median age was 42 years (IQR 30 - 55). Mean baseline HbA1c was 65±15 mmol/mol. Pre-FM, 34.2% had HbA1c <58 mmol/mol (7.5%) which rose to 50.9% at next follow-up (median 343 days from baseline HbA1c), P < 0.001. Those with HbA1c > 75 mmol/mol (9.0%) fell from 17.8% to 8.5%, P < 0.001. Mean reduction in HbA1c was 5.6±10.9 mmol/mol (P < 0.001) but was greater in those with baseline HbA1c above 75mmol/mol (-15.4±16.8 mmol/mol, P < 0.001). In the control group, HbA1c did not change across the corresponding period (+0.2 mmol/mol, P = 0.66). In multivariate analysis, less frequent SMBG pre-FM (P = 0.03), higher HbA1c (P <0.001) and higher socioeconomic status (P = 0.02) were all associated with greater likelihood of a ≥5 mmol/mol fall in HbA1c. Impaired awareness of hypoglycemia (IAH) improved, in those with a prior history of IAH, after FM use (P < 0.001). HADS depression (2 [1 - 5] vs. 1 [0 - 3], P < 0.0001) and anxiety scores (2 [1 - 5] vs. 1 [0 - 3], P = 0.03) were higher following FM use. DKA admissions fell significantly (2 vs. 8, P = 0.02) but no effect was observed on total admissions or emergency department attendance. Blood glucose test strip prescribing fell to 14.3% of pre-FM levels (P < 0.01). FM is associated with reduced DKA admissions and marked improvement in glycemic control across a wide range of people with T1DM. Disclosure F.W. Gibb: None. R.H. Stimson: None. J.A. McKnight: Other Relationship; Self; Boehringer Ingelheim International GmbH, Lilly Diabetes, MedImmune, Novo Nordisk Inc. V. Tyndall: None. S.A. Ritchie: Other Relationship; Self; MedImmune, Novo Nordisk Inc. N.N. Zammitt: None. A.R. Dover: Other Relationship; Self; Abbott.