FRISC-II (Fragmin and/or early Revascularization during InStability in Coronary artery disease) study, elevated IL-6 (5 ng/L) was associated with higher 6-and 12-month mortality and was additive to and independent of cardiac troponin T status. 7 Elevated IL-6 levels also identified a subgroup of patients who derived the greatest mortality benefit from an early invasive strategy. These results suggest that an elevated level of IL-6 may identify patients with a more severe index event, who would therefore benefit from more aggressive treatment. Currently, however, the large circadian variations in IL-6 levels and lack of confirmatory studies limit the applications of IL-6 as a biomarker in ACS.