IL6 and asthma: The inflammatory cytokines interleukin-6 and interleukin-17 have been shown to be related to the severity of asthma.14 Interestingly, we also found that interleukin-6 levels are independently associated with CVsA.15 In a recent in vitro study,16 we demonstrated that increased level of interleukin-6 was associated with a decrease in endothelial nitric oxide synthase activation and subsequently a decrease in nitric oxide bioavailability.