Background and Aims: Insulin Degludec (IDeg) , in comparison with Insulin Glargine U100 (IGla) , reduces the risk of hypoglycemic events in people with type 1 diabetes (T1D) . The impact on CGM assessed glycemic metrics: the coefficient of variation (CV) , time in range (TIR) , time below range (TBR) , and time-above range (TAR) is less known. We present CGM results from the HypoDeg trial comparing treatment with IDeg and IGla in people with T1D and recurrent nocturnal severe hypoglycemia.
Materials and Methods: This is a pre-defined optional substudy of the HypoDeg trial: a 2-year investigator-initiated, randomized, cross-over trial comparing treatment with IDeg or IGla in 149 participants with T1D and at least one nocturnal severe hypoglycemic event within the last two years. Participants underwent 2 x 6 days of blinded CGM (Medtronic iPro) in each treatment arm after 6 and 12 months of treatment. Seventy-four participants completed at least one CGM period in each treatment arm. The endpoints were CV, TIR (3.9 - 10.0 mmol/L) , TBR at level 2 (< 3.0 mmol/L) and TAR (>10.0mmol/L, >13.9mmol/L) . Time spent in, below, or above range provided as percentage of readings.
Results: We collected 261 CGM traces with a mean (SD) observation period of 5.9 (0.7) days. The all-day CV was lower with IDeg than IGla, with a mean (SE) CV of 40.5% (0.9) and 42.5% (0.9) , respectively (p=0.009) . A difference in CV during the night (23:00h to 07:00h) drove this, with a mean CV of 35.7% (1.1) for IDeg versus 39.6% (1.1) for IGla (p=0.001) . The all-day level 2 TBR was lower with IDeg than IGla, with a mean TBR of 1.8% (0.4) and 3.1% (0.4) , respectively (p=0.001) . The percentages of TIR and TAR were not different between treatments.
Conclusion: In people with T1D prone to nocturnal severe hypoglycemia, treatment with IDeg results in a lower mean CV, reaching the definition of stable glucose levels during the night and a lower all-day TBR than IGla.
J.M.Brøsen: None. S.Lerche: None. K.Nørgaard: Advisory Panel; Medtronic, Novo Nordisk A/S, Consultant; Novo Nordisk A/S, Research Support; Dexcom, Inc., Medtronic, Novo Nordisk A/S, Zealand Pharma A/S, Speaker's Bureau; Medtronic, Stock/Shareholder; Novo Nordisk A/S. L.Tarnow: None. B.Thorsteinsson: None. U.Pedersen-bjergaard: Advisory Panel; Novo Nordisk A/S, Sanofi. R.Agesen: Employee; Novo Nordisk A/S. A.Alibegovic: Employee; Novo Nordisk A/S, Novo Nordisk A/S. H.U.Andersen: Advisory Panel; Abbott Diabetes, Stock/Shareholder; Novo Nordisk A/S. P.Gustenhoff: Advisory Panel; Abbott Diagnostics. T.K.Hansen: None. C.Hedetoft: None. C.R.Stolberg: None. C.B.Juhl: None.