Background: Hospitalizations due to worsening chronic heart failure (CHF) are common. However, the relationship between a single measurement of soluble ST2 protein (sST2) and the necessity of hospitalization in CHF is still unclear.Objectives: The aim of this study was to determine the association between a single measurement of sST2 concentration and hospitalizations due to worsening CHF during a one-year follow-up. Material And Methods: The study involved 167 consecutive patients (mean age 63 years, 83% males) with CHF in stable NYHA classes I-III with left ventricular ejection fraction (LVEF) ≤ 45% (median 29.65%, range 13-45%). Fifty-six variables were analyzed (clinical factors, basic laboratory results on admission, standard 12-lead ECG, echocardiography and coronary arteriography results). Information about hospitalizations due to worsening CHF was obtained during telephone interviews conducted 12 months after discharge from the cardiac ward. In order to define factors associated with hospitalization, uniand multivariate regression analyses were performed.Results: A total of 53 patients from the study group (38%) were hospitalized due to worsening CHF. They included a higher percentage of males (p = 0.042), higher concentrations of sST2 (p = 0.049), and glucose (p = 0.010). The multivariate analysis (for model χ2 = 17.235; p < 0.001) revealed that glucose and sST2 were independently associated with hospitalization due to worsening CHF during the 1-year observation (p < 0.001).Conclusions: In patients with stable mild to moderate CHF with reduced EF, a single measurement of sST2 protein and glucose were independent variables for hospitalization due to worsening CHF over a 1-year follow-up period. The defined prognostic model including sST2 and fasting glucose better identified patients without HF-related hospitalizations.