Differential Impact of Admission C-Reactive Protein Levels on 28-Day Mortality Risk in Patients With ST-Elevation Versus Non–ST-Elevation Myocardial Infarction (from the Monitoring Trends and Determinants on Cardiovascular Diseases [MONICA]/Cooperative Health Research in the Region of Augsburg [KORA] Augsburg Myocardial Infarction Registry)

The present study investigated the association between C-reactive protein (CRP) on admission independently and in combination with troponin and short-term prognosis in an unselected sample of patients with acute myocardial infarction (AMI) from the community. The study population consisted of 1,646 patients aged 25 to 74 years who were consecutively hospitalized with AMI within 12 hours after symptom onset. They were divided into the 2 groups of CRP positive (n = 919) or CRP negative (n = 727) with respect to admission CRP (cutoff ≤0.3 mg/dl). CRP-positive patients had significantly more in-hospital complications and a higher 28-day case-fatality rate (9.6% vs 3.4%; p <0.0001). Troponin at admission (n = 1,419) also correlated with 28-day case-fatality rate (troponin-negative 3.4% vs troponin-positive patients 8.0%; p <0.002). Multivariable analysis showed that both troponin positivity and CRP positivity were associated with a 2-fold (adjusted odds ratio 1.99, 95% confidence interval 1.15 to 3.44; adjusted odds ratio 2.05, 95% confidence interval 1.09 to 3.84, respectively) increased risk of dying within 28 days after the acute event for all patients with AMI. Stratifying by AMI type showed that in patients with ST-elevation myocardial infarction (STEMI), troponin positivity, but not CRP positivity, independently predicted 28-day case fatality. In patients with non-STEMI, CRP positivity, but not troponin positivity, predicted outcome. In conclusion, admission CRP was a powerful parameter for risk stratification of patients with AMI. Stratification by AMI type and troponin showed that CRP was a better short-term risk predictor for patients with non-STEMI, and troponin was, for patients with STEMI.