Canadian Journal of Diabetes · Jun 10, 2025

Do Provincial Formulary Restrictions Explain Differential Uptake of Sodium-Glucose Cotransporter-2 Inhibitors in Adults With Diabetes and Cardiovascular Disease in Canada? A Retrospective Cohort Study of Pharmacy Claims

By Lau D, Dover DC, Qureshi H et al.

OBJECTIVES: Ontario listed sodium-glucose cotransporter-2 inhibitors (SGLT2is) as a regular public drug benefit for adults ≥65 years of age, whereas other Canadian provinces providing benefits for SGLT2is have implemented special authorization restrictions. We hypothesized that special authorization led to lower SGLT2i use among older adults with diabetes and cardiovascular disease (CVD) in other provinces (Alberta, Manitoba, New Brunswick, and Saskatchewan) as compared with Ontario. METHODS: We performed a retrospective cohort study of adults with diabetes and CVD who were ≥65 years of age and discharged from hospital between April 1, 2016, and March 31, 2019, in 5 Canadian provinces. Data were obtained from a national discharge database linked with public pharmacy claims. We followed individuals from discharge until March 31, 2019, for SGLT2i uptake. We also examined SGLT2i discontinuation and sulfonylurea uptake as control outcomes. Fine-Gray hazard models were adjusted for comorbidities and area-level sociodemographics. RESULTS: Of 161,249 individuals (average age 78 years, 42% female, median follow-up 1.8 years), 68% were from Ontario and 32% were from other provinces. Cumulative SGLT2i uptake at 6 months was 2.2% in Ontario as compared with 0.7% in other provinces, with an adjusted hazard ratio (aHR) of 2.72 (95% confidence interval 2.56 to 2.94, p<0.001). Ontario residents had similar SGLT2i discontinuation or sulfonylurea uptake compared with other provinces. Other predictors of SGLT2i uptake were identified. CONCLUSIONS: There was an interprovincial disparity in SGLT2i uptake in older adults with diabetes and CVD, among whom SGLT2is are now indicated for cardiorenal benefit. Special authorization restrictions should be flexibly and rapidly reassessed and revised as new evidence of clinical benefits becomes available.

doi.org/10.1016/j.jcjd.2025.06.001Open accessPubMed 40505962Populations