Abstract
Background: Sodium-glucose cotransporter 2 inhibitors (SGLT2i) reduce mortality and morbidity in patients with heart failure (HF). However, their efficacy and safety in underweight patients remain uncertain. This study aimed to evaluate the efficacy and safety of SGLT2i in underweight patients with HF. Methods: This study was a single-center, prospective observational study designed to assess the efficacy of SGLT2i therapy in underweight patients with HF. The primary outcome was a composite of unplanned hospitalization for HF or death from cardiovascular causes. A key secondary outcome was hospitalization from any cause. Results: This study enrolled 131 consecutive patients with a body mass index (BMI) > 18.5 kg/m(2) hospitalized for HF between December 2020 and October 2023. The median age of the study population was 81 (73-87) years, and 60% were female. Baseline BMI was 17.2 (16.0-17.9) kg/m(2). Of these, 28 patients initiated SGLT2i during index hospitalization, while the remaining 103 did not receive SGLT2i. Over a median of 20.4 months of follow-up, the primary outcome occurred in 6 of 28 patients (21.4%) with SGLT2i and 22 of 103 patients (21.4%) without SGLT2i (p = 0.758). All-cause hospitalizations occurred in 23 of 28 patients (82.1%) with SGLT2i and 65 of 103 patients (63.1%) without SGLT2i (p = 0.009). Patients receiving SGLT2i showed a significant decrease in BMI at discharge, 1 month after discharge, and 3 months after discharge compared with those without SGLT2i (p < 0.05 for each time point). Conclusions: SGLT2i in underweight patients with HF may not reduce cardiovascular event risk and may be associated with a higher rate of overall hospitalizations.