Independent prognostic value of C-reactive protein and troponin I in patients with unstable angina or non-Q-wave myocardial infarction

Objectives: Elevated concentrations of C-reactive protein (CRP), a non-spec ific acute phase reactant, and troponin I (TnI), a cardiac-specific marker of myocardial damage, have been found to be associated with a higher risk f or cardiac events in patients with an acute coronary syndrome. We evaluated CRP alone and in combination with TnI for predicting the incidence of majo r cardiac complications within 6 months in patients with unstable angina or non-Q-wave infaction (NQMI). Methods: CRP and TnI was measured on admissio n in patients with unstable angina or NQMI, but results were kept blinded. Patients were treated according to a conservative management strategy, and the incidence of major cardiac events within 6 months was assessed. Results : An abnormal CRP (>5 mg/l) and an abnormal TnI (>0.4 mu g/l) were more fre quent in patients that suffered a major cardiac event (CRP: 93 vs. 35%, P<0 .0001; TnI: 73 vs. 26%, P<0.001). The incidence of major cardiac events was higher in patients with an abnormal CRP than in patients with a normal CRP , both when TnI was abnormal (42 vs. 4.5%, P=0.003) and when TnI was normal (11 vs. 0%, P=0.014). Mean event-free survival was excellent in patients w ith both a normal CRP acid TnI, whereas survival was poorest in patients wi th both an abnormal CRP and TnI (121+/-16 vs. 180 days, P<0.0001). Conclusi ons: An abnormal CRP on admission in patients with unstable angina or NQMI is associated with increased incidence of major cardiac events within 6 mon ths, both in patients with normal and abnormal TnI. CRP and TnI. have indep endent and additive prognostic value in this patient group, and the combina tion may be useful for early risk stratification. (C) 1999 Elsevier Science B.V. All rights reserved.