Torsemide vs Furosemide Among Patients With New-Onset vs Worsening Chronic Heart Failure A Substudy of the TRANSFORM-HF Randomized Clinical Trial

Importance Differences in clinical profiles, outcomes, and diuretic treatment effects may exist between patients with de novo heart failure (HF) and worsening chronic HF (WHF).Objectives To compare clinical characteristics and treatment outcomes of torsemide vs furosemide in patients hospitalized with de novo HF vs WHF.Design, Setting, and Participants All patients with a documented ejection fraction who were randomized in the Torsemide Comparison With Furosemide for Management of Heart Failure (TRANSFORM-HF) trial, conducted from June 18 through March 2022, were included in this post hoc analysis. Study data were analyzed March to May 2023.Exposure Patients were categorized by HF type and further divided by loop diuretic strategy.Main Outcomes and Measures End points included all-cause mortality and hospitalization outcomes over 12 months, as well as change from baseline in the Kansas City Cardiomyopathy Questionnaire Clinical Summary Score (KCCQ-CSS).Results Among 2858 patients (mean [SD] age, 64.5 [14.0] years; 1803 male [63.1%]), 838 patients (29.3%) had de novo HF, and 2020 patients (70.7%) had WHF. Patients with de novo HF were younger (mean [SD] age, 60.6 [14.5] years vs 66.1 [13.5] years), had a higher glomerular filtration rate (mean [SD], 68.6 [24.9] vs 57.0 [24.0]), lower levels of natriuretic peptides (median [IQR], brain-type natriuretic peptide, 855.0 [423.0-1555.0] pg/mL vs 1022.0 [500.0-1927.0] pg/mL), and tended to be discharged on lower doses of loop diuretic (mean [SD], 50.3 [46.2] mg vs 63.8 [52.4] mg). De novo HF was associated with lower all-cause mortality at 12 months (de novo, 65 of 838 [9.1%] vs WHF, 408 of 2020 [25.4%]; adjusted hazard ratio [aHR], 0.50; 95% CI, 0.38-0.66; P < .001). Similarly, lower all-cause first rehospitalization at 12 months and greater improvement from baseline in KCCQ-CSS at 12 months were noted among patients with de novo HF (median [IQR]: de novo, 29.94 [27.35-32.54] vs WHF, 23.68 [21.62-25.74]; adjusted estimated difference in means: 6.26; 95% CI, 3.72-8.81; P < .001). There was no significant difference in mortality with torsemide vs furosemide in either de novo (No. of events [rate per 100 patient-years]: torsemide, 27 [7.4%] vs furosemide, 38 [10.9%]; aHR, 0.70; 95% CI, 0.40-1.14; P = .15) or WHF (torsemide 212 [26.8%] vs furosemide, 196 [24.0%]; aHR, 1.08; 95% CI, 0.89-1.32; P = .42; P for interaction = .10), In addition, no significant differences in hospitalizations, first all-cause hospitalization, or total hospitalizations at 12 months were noted with a strategy of torsemide vs furosemide in either de novo HF or WHF.Conclusions and Relevance Among patients discharged after hospitalization for HF, de novo HF was associated with better clinical and patient-reported outcomes when compared with WHF. Regardless of HF type, there was no significant difference between torsemide and furosemide with respect to 12-month clinical or patient-reported outcomes.