Time-course of changes in levels of interleukin 6 in acutely decompensated heart failure

Cytokines are thought to be involved in the physiopathology of heart failure, although its role is not fully understood. The study of Suzuki et al. adds some light to the behaviour of cytokines in patients with acutely decompensated heart failure [1]. High levels of cytokines in these patients could be explained by neurohormonal activation and pro-inflammatory cytokine gene expression secondary to acute hemodynamic pressure overloading. However, clinical usefulness of this test might be limited. We measured interleukin-6 (IL-6) level in a group of 111 patients with decompensated heart failure, who were then followed-up for 21 months. Although IL-6 rose during acute heart failure, its level did not correlate with clinical outcome, nor had prognostic value (unpublished data). Hence, acute increase of cytokine levels does not necessarily correlate with clinical outcome. Previous studies have demonstrated a limited prognostic value of cytokines and neurohormones in patients with advanced heart failure [2]. Cytokine concentrations in peripheral blood are unstable and modifiable by different factors either clinical or pharmacological, present in patients with heart failure. In addition, patients with heart failure are elderly in a high percentage. Ageing produces changes in expression of