In addition, increased levels of IL-6 have been reported in CHF patients and are correlated to plasma levels of NE (R = 0.839, p < 0.0001).20 In our study, plasma levels of IL-1β, IL-6, IL-10, IFN-α, IFN-β, and TNFR1 were below the detection limit. This evidence concerns the gene IFNB1 and congestive heart failure.