The use of isCGM leads to marked reduction in severe hypoglycemia requiring emergency medical service or hospital admission and diabetic ketoacidosis in adult type 1 diabetes patients.

"Declarations Conflict of interestJanne Martikainen is a founding partner of ESiOR. This company was not involved in carrying out this research. The other authors declare that they have no conflict of interest. Human and animal rightsThis article does not contain any studies using human or animal subjects performed by any of the authors. Informed consent statementAccording to the Finnish legislation, register authorities give permissions to use register data including sensitive individual information (e.g., health data) to study specified research questions to named individuals who have signed a pledge of secrecy. The joint municipal authority for North Karelia Social and Health services (Siun sote) has given a permission for the use of the data. The Finnish legislation do not require ethics approcla nor informed consent for register-based research when study is solely based on registers (involving no contact with the study subjects) and the study is considered to be of public health importance. Conflict of interest Janne Martikainen is a founding partner of ESiOR. This company was not involved in carrying out this research. The other authors declare that they have no conflict of interest."

"Funding Open access funding provided by University of Eastern Finland (UEF) including Kuopio University Hospital. The funding for this study came from the Siun sote fund and was partly funded by the Research Committee of the Kuopio University Hospital Catchment Area for the State Research Funding (project QCARE, Joensuu, Finland), the Strategic Research Council at the Academy of Finland (project IMPRO, 312703 and 336325), and the Finnish Diabetes Association. No funding from Abbott Diabetes was included."