ABSTRACT
Aims: Regional variations in adoption of real-time continuous glucose monitoring (RT-CGM) may be reflected in population-level metrics of glycaemic control. In this observational study, we characterised the impact of two different RT-CGM systems in three European countries. Methods: Anonymised data from users in Germany, Sweden, and the UK who transitioned from Dexcom's G5 to its G6 RT-CGM System in 2018 and uploaded data from both systems were analysed. The G6 (but not G5) feature set includes a predictive alert designed to mitigate hypoglycaemia. Endpoints were time in range (TIR, 3.9-10.0mmol/ L), retention rates, and intraday/interday device utilisation. Metrics were computed for three month intervals in the two year study window following G6 launches. Results: Utilisation among G5-to- G6 transitioners improved across all countries, and the user retention rate at the end of the study was 85.5%. Overall mean TIR increased from 60.1% (final three months of G5) to 62.8% (two years after switching to G6), and the proportion achieving >70% TIR increased from 28.3% to 37.9%.Regional TIR differences were observed in 2020 and may have been influenced by covid-19 lockdown approaches. Pandemic-related increases in TIR were evident in the UK and Germany, where stringent lockdown measures were introduced;TIR changes in Sweden, where lockdowns were less restrictive, were negligible. Conclusions: Population-level analysis of RT-CGM data can reveal nationwide trends and disparities in the adequacy of glycaemic control. These may be impacted by factors including features and performance attributes of the RT-CGM system itself, and by public health measures such as lockdowns.