Longitudinal treatment patterns in patients recently diagnosed with type 2 diabetes mellitus in Catalonia

Aim: To investigate initial and subsequent treatments prescribed to newly diagnosed type 2 diabetes mellitus (T2DM) patients. Methods: Data from SIDIAP (Information System for Research in Primary Care) including all recorded incident T2DM patients in primary care between 2015 and 2020. We used descriptive statistics and different graphical techniques to describe the most frequent longitudinal patterns. Results: A total of 86,854 patients were included. 78.3 % of the patients began treatment with a single metformin medication and 21.7 % began with a combination therapy (CT). Metformin was the most frequent treatment as first and third-line therapy, while the CT of metformin with DPP4i or sulfonylurea was more prevalent as second-line. Most common first to third-line pattern was initial metformin for 15 months, adding a second antidiabetic in the second line, staying in CT for 6 months, and switching back to single metformin. Treatment patterns varied depending on HbA1c levels, with higher levels (>8 %) being associated with changes to CT and lower levels with switches to monotherapy or temporary discontinuation. Conclusion: The study described in detail the different treatment patterns in incident T2DM patients in Catalonia, its adherence to the guidelines, and how the changes are associated to the HbA1c dynamics.