BACKGROUND: The aims of this study were to: (i) report the baseline characteristics of patients enrolled in the Dapagliflozin And Prevention of Adverse-outcomes in Heart Failure (DAPA-HF) trial, (ii) compare DAPA-HF patients to participants in contemporary heart failure (HF) registries and in other recent HF trials, and (iii) compare individuals with diabetes, pre-diabetes and a normal glycated haemoglobin (HbA1c) in DAPA-HF.

METHODS AND RESULTS: Adults with HF in New York Heart Association functional class ≥ II, a left ventricular ejection fraction ≤ 40%, an elevated N-terminal pro-B-type natriuretic peptide concentration and receiving standard treatment were eligible for DAPA-HF, which is comparing dapagliflozin 10 mg once daily to matching placebo. In patients without a history of diabetes, previously undiagnosed diabetes was defined as a confirmed HbA1c ≥ 6.5%. Among patients without known or undiagnosed diabetes, pre-diabetes was defined as a HbA1c ≥ 5.7% The remainder of patients, with a HbA1c < 5.7%, were defined as normoglycaemic. Of the 4744 patients (mean age 66 years; 23% women) randomized, 42% had known diabetes and 3% undiagnosed diabetes. Of the remainder, 67% had pre-diabetes and 33% normal HbA1c. Overall, DAPA-HF patients were generally similar to those in recent registries and in relevant trials and had high levels of background therapy: 94% angiotensin-converting enzyme inhibitor/angiotensin receptor blocker/angiotensin receptor-neprilysin inhibitor, 96% beta-blocker, and 71% mineralocorticoid receptor antagonist; 26% had a defibrillator. Patients with diabetes had worse HF status, more co-morbidity, and greater renal impairment but received similar HF therapy. Patients with diabetes received non-insulin hypoglycaemic therapy alone in 49%, insulin alone in 11%, both in 14%, and none in 26%.

CONCLUSIONS: Patients randomized in DAPA-HF were similar to those in other contemporary HF with reduced ejection fraction (HFrEF) registries and trials. These patients were receiving recommended HFrEF therapy and those with diabetes were also treated with conventional glucose-lowering therapy. Consequently, DAPA-HF will test the incremental efficacy and safety of dapagliflozin in HFrEF patients with and without diabetes.

CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov Identifier NCT03036124.