Weight loss as a marker of successful decongestion during acute heart failure hospitalisation

Background Effective decongestion is a key therapeutic goal during hospitalisation for acute heart failure (HF), but the clinical significance of intravenous loop diuretic-induced weight loss and its relationship with biomarker changes remain uncertain. Methods We included patients hospitalised for HF in the nationwide Swedish Heart Failure Registry (2017–2021) who received intravenous loop diuretics, survived to discharge and had body weight recorded at admission and discharge. Weight loss was defined as ≥2 kg between admission and discharge. Associations between weight loss, changes in biomarkers (estimated glomerular filtration rate (eGFR), N-terminal pro-B-type natriuretic peptides (NT-proBNP), haemoglobin, sodium and potassium) and outcomes were evaluated. The primary outcome was rehospitalisation for HF (re-HHF); the secondary outcome was the composite of cardiovascular death or re-HHF at 30 days and 1 year. Results Among 4979 patients (median age 80 years; 57% male), median weight change during hospitalisation was −2.5 kg and 2949 (59%) achieved weight loss ≥2 kg. Male sex, atrial fibrillation, obesity, higher admission NT-proBNP and mineralocorticoid receptor antagonist use were independently associated with weight loss. Weight change showed no meaningful association with change in eGFR. Weight loss was independently associated with a lower risk of re-HHF (HR 0.59, 95% CI 0.53 to 0.67) and the composite of cardiovascular death or re-HHF (HR 0.76, 95% CI 0.69 to 0.84) within 30 days but not thereafter. These associations were consistent irrespective of biomarker changes, including worsening renal function. Conclusions In this nationwide cohort of patients hospitalised for HF and treated with intravenous loop diuretics, diuretic-induced weight loss, a pragmatic marker of decongestion, was associated with improved short-term clinical outcomes without an accompanying decline in renal function and irrespective of biomarker changes, including worsening renal function.