Prognostic value of cytokines and chemokines in addition to the GRACE Score in non-ST-elevation acute coronary syndromes

BackgroundIncreased cytokine and chemokine levels are associated with cardiovascular events in patients with non-ST-elevation acute coronary syndromes (ACS), but the incremental prognostic value of these inflammatory markers is not known. We determined if cytokine and chemokine assessment adds prognostic information to the GRACE Score in patients with ACS.MethodsFive cytokines (interleukin (IL)-1β, IL-6, IL-10, IL-12p70, and tumor necrosis factor (TNF)-α soluble receptor I), five chemokines (IL-8, CCL5, CXCL9, CCL2, and CXCL10) and C-reactive protein (CRP) were measured at admission of 87 patients admitted with ACS.ResultsDuring hospitalization, the incidence of cardiovascular events was 13% (7 deaths, 1 nonfatal acute myocardial infarction, and 3 refractory unstable angina). Individuals who developed events had significantly greater levels of CRP, IL-1β, IL-12, TNF-α, IL-8, CXCL9 and CCL2, compared with those free of events. Thus, these markers were used to build an Inflammatory Score, by the input of one point for each of these variables above the 75th percentile. After adjustment for the GRACE Score, the Inflammatory Score independently predicted events (OR = 1.80; 95% CI = 1.12–1.88). Incorporation of the Inflammatory Score into the GRACE Score promoted a C-statistics improvement from 0.77 (95% CI = 0.58–0.96) to 0.85 (95% CI = 0.71–1.0). Net reclassification improvement obtained with GRACE–Inflammatory Score was 13% (P = 0.007), indicating a significant reclassification. When only CRP was incorporated into GRACE, the increase on C-statistics was not relevant (from 0.77 to 0.80).ConclusionCytokines and chemokines measured at admission add prognostic information to the GRACE Score in patients admitted with ACS.