Background: Heart failure (HF) is associated with high mortality, morbidity, and impaired quality of life. Randomised trials show that sodium–glucose cotransporter2 inhibitors (SGLT2i) reduce mortality and hospitalisations across HF phenotypes. Evidence on their effectiveness in real-world patients, who are mostly sicker than those in clinical trials —particularly those in New York Heart Association (NYHA) class III–IV—remains limited.
Objective: To compare all-cause mortality and HF-related hospitalisations in real-world HF patients with NYHA class III and IV treated with and those without SGLT2i.
Methods: We conducted a retrospective analysis of anonymised German statutory health insurance claims for 2024. This dataset comprised approximately 4.5 million insured individuals and was representative by age, sex, and morbidity. Results are presented as extrapolated estimates to the national population unless stated otherwise. HF patients were identified irrespective of ejection fraction phenotype using ICD10 codes (I50.01, I50.1, I50.5, I11.0, I13.0, I13.2), resulting in a projected number of HF population of 4,195,239 patients. Medication exposure was captured via ATC codes. Outcomes included all-cause mortality and HF-related hospitalisations, stratified by NYHA class (III, IV) and SGLT2i use. All analyses were purely descriptive and unadjusted; no correlations, regression analyses, or causal inference methods were applied.
Results: Among the projected 4,195,239 patients with HF, NYHA class was available for 2,382,741: 10.7% (254,648) NYHA I, 34.7% (827,236) NYHA II, 35.7% (849,612) NYHA III, and 18.9% (451,245) NYHA IV. 46.8% (n=397,353) of HF patients with documented NYHA III status received SGLT-2i. All-cause mortality rate in NYHA class III with SGLT2i was 12.3% and 17.2% without. HF-related hospitalisations in NYHA III occurred in 16.0% with SGLT2i and 21.7% without. SGLT2i prescriptions were similar in the cohort of NYHA IV categorised HF-patients: 49.6% (n=223,759) received SGLT2i. All-cause mortality rate in this population was 41.5% with SGLT2i and 48.3% without. HF-related hospitalisations occurred in 52.9% with SGLT2i and 62.7% without.
Conclusions: In this nationwide real-world cohort of advanced HF, SGLT2i use was associated with lower all-cause mortality and fewer HF-related hospitalisations, yet only approximately half of eligible patients received SGLT2i, highlighting a clear implementation gap. The observed patterns are consistent with the known mechanism of action and the existing body of randomised trial evidence but do not replace causal evidence. The findings support tailored strategies to improve equitable SGLT2i initiation and persistence, with attention to patient selection, access, and ambulatory care pathways.
