Background: Procalcitonin (PCT) is an established biomarker for the diagnosis of sepsis. Evidence is growing that PCT concentration correlates with the extent of atherosclerosis and prognosis in patients with coronary artery disease (CAD).
Methods and results: A total of 2,131 patients with CAD were followed up for a median of 3.6 years. During follow-up, death from cardiovascular causes was registered in 95 patients and non-fatal myocardial infarction in 85 patients. Median and quartile 1 and 3 are reported for PCT concentration. Patients who died of cardiovascular causes had higher PCT concentrations [0.021 (0.012/0.036) ng/ml vs. 0.015 (0.010/0.023) ng/ml; P<0.0001]. Patients with acute coronary syndrome had increased concentrations of PCT in relation to patients with stable angina [0.016 (0.011/0.027) ng/ml vs. 0.014 (0.009/0.014) ng/ml; P for trend <0.0001]. PCT concentration across quartiles was associated with the event rate (P=0.026; log-rank test) and mortality (P=0.00018). On Cox regression analysis, elevated PCT concentration was related to cardiovascular mortality [hazard ratio (HR), 1.34; 95% confidence interval (CI): 1.08-1.65, P=0.0070], but not to cardiovascular events (HR, 1.09; 95%CI: 0.93-1.28, P=0.28). After adjustment for C-reactive protein (CRP), PCT did not provide additional prognostic information.
Conclusions: PCT is associated with future cardiovascular mortality in patients with CAD, but PCT is not superior to CRP for prediction of outcome.