Diabetes mellitus (DM) is a well-established risk factor for adverse prognosis in patients with heart failure (HF). The combination of HF and DM confers an increased risk for hospitalization and worse health outcomes (1). The prevalence of DM among patients with HF is 24%, over two times higher than the population average.(2) Sodium/glucose cotransporter-2 inhibitors (SGLT2i) have been commercially available for over ten years but. until recently, were primarily used to treat Type 2 Diabetes Mellitus (T2DM) as a glucose-lowering agent. In 2015, the Empagliflozin, Cardiovascular Outcomes, and Mortality in Type 2 Diabetes (EMPA-REG) study demonstrated that HF hospitalizations decreased by 35% following SGLT2i treatment.(3) In 2019, the first outcome trial of SGLT2i in T2DM patients with Heart failure with a reduced ejection fraction (HFrEF) reported reduced all-cause mortality and cardiovascular (CV) mortality.(4) Subsequently, the Dapagliflozin in Patients with Heart Failure and Reduced Ejection Fraction (DAPA-HF) and Cardiovascular and Renal Outcomes with Empagliflozin in Heart Failure (EMPEROR Reduced) trials demonstrated a reduction in the risk of worsening HF or CV mortality in patients with HF independent of DM status.(5,6) In 2021, the Empagliflozin in Heart Failure with a Preserved Ejection Fraction (EMPEROR Preserved) trial reported that the risk of CV mortality or HF hospitalization was lower for patients treated with empagliflozin with a left ventricular ejection fraction (LVEF) greater than 40% known as heart failure with mid-range ejection fraction (HFmrEF) and heart failure with a preserved ejection fraction (HFpEF) (7) – a result confirmed by the Dapagliflozin in Heart Failure with Mildly Reduced or Preserved Ejection Fraction, (DELIVER) trial with dapagliflozin in 2022.(8) These clinically important improvement in outcomes have also translated to a meaningful improvement in functional status as well.(9)

Given the effectiveness of SGLT2i in the HF and DM population from randomized trials, we designed this study to compare the uptake of SGLT2i and associated outcomes in two cohorts: a population-based cohort of all adults with DM and HF in Alberta, Canada and a specialized heart failure clinic (HFC) cohort based at the Mazankowski Alberta Heart Institute (MAHI) in Edmonton, Alberta.