Type 1 diabetes and COVID-19: the "Lockdown effect"

Aims: The aim of this study was to evaluate the effect the lockdown imposed during COVID-19 outbreak on the glycemic control of people with Type 1 diabetes (T1D) using Con- tinuous (CGM) or Flash Glucose Monitoring (FGM). Materials and methods: We retrospectively analyzed glucose reading obtained by FGM or CGM in T1D subjects. Sensor data from 2 weeks before the lockdown (Period 0, P0), 2 weeks immediately after the lockdown (period 1, P1), in mid-lockdown (Period 2, P2) and immedi- ately after end of lockdown (Period 3, P3) were analyzed. Results: The study included 63 T1D patients, (FGM: 52, 82%; CGM:11, 18%). Sensor use (91%) were slightly reduced. Despite this reduction, Time in Range increased in P1 (62%), P2 (61%) and P3 (62%) as compared to P0 (58%, all p < 0.05 or less) with concomitant reduction in the Time Above Range (P0: 38%; P1: 34%, P2: 34%, P3: 32%, all p < 0.05 or less vs. P0). Average glu- cose and GMI improved achieving statistical difference in P3 (165 vs. 158 mg/dl, p = 0.040 and 7.2% (55 mmol/mol) vs. 7.0% (53 mmol/mol), p = 0.016) compared to P0. Time Below Range (TBR) and overall glucose variability remained unchanged. Bi-hourly analysis of glu- cose profile showed an improvement particularly in the early morning hours. Conclusions: In T1D subjects with good glycemic control on CGM or FGM, the lockdown had no negative impact. Rather a modest but significant improvement in glycemic control has been recorded, most likely reflecting more regular daily life activities and reduces work- related distress.