Copeptin, Routine Laboratory Parameters, and Ischemic Etiology of Heart Failure Predict Outcomes in Elderly Patients with Decompensated Heart Failure

<b>Background</b>: Diagnosing and predicting outcomes in elderly patients with heart failure (HF) is challenging due to atypical symptoms and the limited value of natriuretic peptides, highlighting the need to search for new risk stratification biomarkers in this population. <b>Aim</b>: We aimed to analyze factors associated with the composite endpoint (all-cause mortality or decompensated HF-related hospitalization) within six months of follow-up in elderly patients with left ventricular systolic dysfunction and decompensated HF, with particular emphasis on copeptin concentration. <b>Methods</b>: This is a retrospective observational study based on prospectively collected data of 279 consecutive elderly patients hospitalized between 2018 and 2023 due to decompensated HF. Inclusion criteria were age > 65 years, history of HF diagnosed at least two years before the index hospitalization, and left ventricular ejection fraction < 40% on admission echocardiography. Serum copeptin levels were measured using an Enzyme-Linked Immunosorbent Assay (ELISA) (Human Copeptin ELISA kit, Sunred Biological Technology Co, Shanghai, China). The primary endpoint was all-cause mortality or decompensated HF-related hospitalization during the six-month follow-up. <b>Results</b>: The median age of the study population was 77 years (IQR: 69-79), and 221 (79.2%) were male. The composite endpoint occurred in 110 patients (38.1%). Multivariable analysis showed that serum concentrations of copeptin [hazard ratio (HR) 1.053 (1.042-1.064), <i>p</i> < 0.0001], bilirubin [HR 1.085 (1.057-1.114), <i>p</i> < 0.0001], uric acid [HR 1.005 (1.003-1.006), <i>p</i> < 0.0001], high-sensitivity C-reactive protein (hs-CRP) [HR 1.208 (1.088-1.342), <i>p</i> < 0.0001], and sodium [HR 1.111 (1.025-1.203), <i>p</i> = 0.01], as well as ischemic etiology of HF [HR 3.969 (2.396-6.575), <i>p</i> < 0.0001], were independently associated with worse outcomes. <b>Conclusions</b>: Our study demonstrated that higher concentrations of copeptin, bilirubin, hs-CRP, and uric acid, as well as lower sodium levels and ischemic etiology of HF, were independently associated with all-cause mortality or HF-related hospitalization during a six-month follow-up in elderly patients with decompensated HF.