Relation between proinflammatory to anti-inflammatory cytokine ratios and long-term prognosis in patients with non-ST elevation acute coronary syndrome.

OBJECTIVE: To investigate the relation between serum high sensitivity (hs) C reactive protein (CRP), proinflammatory cytokine concentrations, proinflammatory to anti-inflammatory cytokine ratios and long-term prognosis in patients with non-ST elevation acute coronary syndrome (NSTEACS).

DESIGN: Prospective follow-up study for the first six months and then for the first year after admission to hospital.

SETTING: Tertiary referral centre.

PATIENTS: 80 patients (60 men, 20 women, mean age 60 (SD 10) years) with NSTEACS and moderate to high TIMI (Thrombolysis In Myocardial Infarction) risk scores.

INTERVENTIONS: Blood samples from patients with NSTEACS were obtained at the time of admission. Serum concentrations of hs-CRP, (hs) pro-inflammatory (interleukin (IL) -1beta, IL-6, tumour necrosis factor alpha) and (hs) anti-inflammatory (IL-10) cytokines were analysed and proinflammatory to anti-inflammatory cytokine ratios were calculated by dividing proinflammatory cytokine concentrations by anti-inflammatory cytokine IL-10.

MAIN OUTCOME MEASURE: The primary end point of the study was new coronary events (NCE) defined as the combination of cardiac death, non-fatal myocardial infarction and recurrent rest angina that required hospitalisation within 12 months of follow up.

RESULTS: During the one-year follow-up period, 23 patients (29%) met the NCE criteria. Concentrations of hs-CRP, IL-1beta and IL-6 and ratios of IL-1beta:IL-10 and IL-6:IL-10 were significantly higher in patients with NCE than in patients without NCE. In the logistic regression analysis, IL-6:IL-10 ratio was the most important predictor for NCE (p = 0.006) with an odds ratio of 2.24 (95% CI 1.26 to 3.97).

CONCLUSIONS: Cytokine concentrations and proinflammatory to anti-inflammatory cytokine ratios may be useful markers for predicting vascular risk in patients with NSTEACS.