Objective. To determine whether inflammatory markers prospectively predict depressive symptom severity 12 months later in heart failure (HF) patients. Methods. In 30 HF patients we assessed depressive symptom severity by the Beck depression inventory (BDI) at baseline as well as 12 months later. We measured circulating levels of the soluble intercellular adhesion molecule (sICAM)-1, the cytokine interleukin (IL)-6 and the acute phase protein C-reactive protein (CRP) at baseline assessment. Results. sICAM-1 (r=.38, p=.045) but not CRP or IL-6 correlated with BDI scores 12 months later. Hierarchical linear regression analysis revealed that independent of baseline BDI assessment, cardiovascular risk factors, indicators of HF disease severity, and medication intake, sICAM-1 significantly predicted BDI scores 12 months later. sICAM-1 independently explained between 7% (beta=.26, p=.040) and 10% (beta=.35, p=.045) of the total variance in BDI scores 12 months later. Conclusion. The findings from this exploratory analysis suggest that the adhesion molecule sICAM-1 is an independent predictor of depressive symptoms 12 months later in HF patients. Our prospective findings support the suggested role for inflammation in increasing future depressive symptom severity and extend this linkage for the first time to HF.