Depressive symptoms and inflammation in patients hospitalized for heart failure

BACKGROUND: Depressive symptoms in patients with heart failure (HF) are common and might be associated with inflammation. No studies have examined both the cross-sectional and prospective association between inflammation and depressive symptoms in patients with HF with adequate correction for disease severity. The aim of this study was to describe if the cytokines interleukin-6 (IL-6) and C-reactive protein (CRP) are associated with depressive symptoms in hospitalized HF patients.

METHODS: Data from 517 patients hospitalized for HF from the COACH study were analyzed on inflammation markers (IL-6 and CRP) and depressive symptoms (Center for Epidemiological Studies Depression-Scale).

RESULTS: Heart failure patients with depressive symptoms (n = 208, 40%) had significantly higher plasma values of IL-6 (median 12.8 pg/mL vs median 11.0 pg/mL, P = .018) and CRP (median 2.4 mg/mL vs median 2.1 mg/mL, P = .03) compared with the nondepressed patients. Structural equation modelling showed that the factor inflammation (including IL-6 and CRP) was associated with depressive symptoms (β = 0.18, P < .05) when left ventricular ejection fraction and plasma values brain natriuretic peptides were included in the model. A small negative (β = -0.18, P < .05) effect was found between inflammation at baseline and the change in depressive symptoms during the 18 months of follow-up.

CONCLUSIONS: Higher levels of inflammatory markers are independently associated with depressive symptoms in HF patients, even after correcting for disease severity. There is no clear relationship between inflammation at baseline and depressive symptoms during the 18 months of follow-up.