Background: The use of flash glucose monitoring (FGM) has expanded widely among diabetic patients. Large randomized controlled trials demonstrated that use of FGM resulted in significant reductions in hypoglycemia, increased time in target range, reduced glycemic variability, and greater patient satisfaction compared with finger stick but no significant effects on glycemic control. Nonetheless, there is sparse guidance for what actions individuals should take based on the trend arrow data.

Aim of the Study: To verify the impact of published recommendation (Bianchi C., Aragona M. J Diabetes Complications. 2018 Oct 24) on glycemic control in type 1 diabetic subjects (T1DM). Patients and Methods: Since January 2018, 145 T1DM patients initiated FGM, after a period of education on the system and how to adjust insulin doses based on trend arrow (Trained Group - TG) and compared to a matched group of 204 patients who started FMG before recommendations were elaborated and therefore not being trained (Not Trained Group - NTG). The two groups showed no significant difference in terms of age, sex, duration of disease, type of treatment, BMI and insulin requirements.

Results: In TG HbA1c at baseline was 59±14 mmol/mol to decline 55±12 mmol/mol at month 6 (p<0.00001). In NTG HbA1c at baseline was 58±14 mmol/mol with minimal though statistically significant reduction after 6 months (56±12 mmol/mol; p<0.04). In both groups there was no change in BMI and Insulin Requirements.

Conclusions and Comments: In our clinical practice, FGM implementation was associated with a small but significant reduction in HbA1c, particularly in trained patients. Prospective and larger studies are needed to validate international guidelines for the education of diabetic patients adopting these new technologies.


C. Rodia: None. C. Bianchi: None. A. Bertolotto: Speaker's Bureau; Self; Abbott, Lilly Diabetes. R. Giannarelli: None. F. Campi: None. S. Gennai: None. S. Del Prato: Advisory Panel; Self; AstraZeneca, Boehringer Ingelheim Pharmaceuticals, Inc., Eli Lilly and Company, GlaxoSmithKline plc., Merck Sharp & Dohme Corp., Novartis Pharmaceuticals Corporation, Novo Nordisk A/S, Sanofi, Servier, Takeda Pharmaceutical Company Limited. Board Member; Self; AstraZeneca. Research Support; Self; AstraZeneca, Boehringer Ingelheim Pharmaceuticals, Inc. Speaker's Bureau; Self; Boehringer Ingelheim Pharmaceuticals, Inc., Takeda Pharmaceutical Company Limited. M. Aragona: None.

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