Trends in diabetes medication use in Canada, England, Scotland and Australia : a repeated cross-sectional analysis (2012-2017)

Abstract

Background: Several new classes of glucose lowering medications have been introduced in the past two decades. Some, such as Sodium-glucose cotransporter 2 inhibitors (SGLT2s), have evidence of improved cardiovascular outcomes, while others, such as Dipeptidyl peptidase-4 inhibitors (DPP4s), do not. It is therefore important to identify their uptake, in order to find ways to support the use of more effective medications. Aims: We studied the uptake of these new classes amongst patients with type 2 diabetes. Design and setting: Retrospective repeated cross-sectional analysis. We compared rates of medication uptake in Australia, Canada, England and Scotland. Method: We used primary care Electronic Medical Data on prescriptions (Canada, UK) and dispensing data (Australia) from 2012 to 2017. We included persons aged 40 years or over on at least one glucose-lowering drug class in each year of interest, excluding those on insulin only. We determined proportions of patients in each nation, for each year, on each class of medication, and on combinations of classes. Results: By 2017, data from 238,609 patients were included. The proportion of patients on sulfonylureas (SUs) decreased in three out of four nations, while metformin decreased in Canada. Use of combinations of metformin and new drug classes increased in all nations, replacing combinations involving SUs. In 2017 more patients were on DPP4s (between 19.1% and 27.6%) than on SGLT2s (between 10.1% and 15.3%). Conclusions: New drugs are displacing SUs. However, despite evidence of better outcomes, the adoption of SGLT2s lagged behind DPP4s.