Therapeutic use of dopamine and beta-blockers modulates plasma interleukin-6 levels in patients with congestive heart failure

We previously reported that the spillover of interleukin-6 (IL-6) into the peripheral circulation increases with the severity of congestive heart failure (CHF), and that the increase is mainly associated with activation of the endogenous sympathetic nervous system. However, the role of the sympathetic nervous system in the increase of IL-6 in CHF patients is not yet fully understood. To address this question, we measured plasma IL-6 levels before and after therapeutic administration of dopamine and betablockers in patients with CHF. After more than 24 h (mean, 34 h) of treatment with a low dose of intravenous dopamine (mean, 2.4 microg/kg/min) in 1 patients with dilated cardiomyopathy and deterioration of CHF, the plasma IL-6 level was increased significantly (30.8 vs. 16.6 pg/ml; p = 0.003) despite the improved hemodynamics. After 377 days of beta-blocker therapy in 24 patients with dilated cardiomyopathy, the plasma IL-6 level was decreased significantly (2.04 vs. 3.11 pg/ml; p = 0.01) along with the improvement of symptoms, left ventricular ejection fraction, and neurohumoral factors. Dopamine increases and beta-blockers decrease the plasma IL-6 level in patients with CHF, suggesting that drugs modulating the sympathetic nervous system may alter IL-6 in these patients.