We sought to evaluate the association between C-reactive protein (CRP) sampled on admission and short- and long-term mortality in patients with acute coronary syndromes (ACS) undergoing early invasive treatment. Baseline levels of CRP were determined in 2,974 patients with moderate and high-risk ACS undergoing an early invasive treatment strategy in the large-scale randomized ACUITY trial. The relationship of CRP to 30-day and 1-year clinical outcomes were assessed according to quartiles of CRP values. Patients with CRP levels in the fourth quartile compared to the first quartile had significantly higher 30-day mortality (2.3 vs. 0.3%, P = 0.0004) and 1-year mortality (5.5 vs. 2.8%, P = 0.0003). CRP level as a continuous variable was associated with 30-day mortality (OR [95% CI] for one unit increase in logarithmically transformed CRP level = 1.42 [1.08-1.89], P = 0.01) and 1-year mortality (OR [95% CI] = 1.24, [1.04-1.47], P = 0.02). By multivariable analysis, higher baseline CRP levels independently predicted 30-day and 1-year mortality, a relationship that was particularly strong for patients with the highest quartile of CRP (OR [95% CI] = 5.19 [1.14-23.68], P = 0.009). In troponin-positive patients, increasing quartiles of CRP were associated with a trend for 30-day mortality (P (trend) = 0.08) and a significant increase in 1-year mortality (P (trend) = 0.02); this relationship was not present in troponin-negative patients. Baseline CRP level is a powerful independent predictor of both early and late mortality in patients with ACS being treated with an early invasive strategy, especially in troponin positive patients.
Trial registration: ClinicalTrials.gov NCT00093158.