Copeptin for risk stratification in acute illness: beyond cardiological problems

Copeptin (Cop) has been recently proposed as a reliable marker for the diagnosis of acute coronary syndrome, altough its concentration was found to increase in a variety of other severe clinical conditions. The aim of the present study was to assess the utility of Cop to identify high-risk patients in the emergency room (ER). Eighty-five patients admitted to ER of the San Maurizio Regional Hospital of Bolzano between February to March 2010 with epigastric or chest pain and/or discomfort were included in the study. Blood was drawn at admission and sampled for Cop in standard laboratory tests. Cop levels were significantly higher in patients who died at the hospital or shortly afterwards as compared with survivors (median 61 vs 40.6 pmol/L; P=0.014). Cop levels were also higher in patients with severe health problems (62.9 vs 28.3 pmol/L; P<0.0001). The area under the receiver-operating characteristic curve of Cop was 0.70 for in-hospital death [95% confidence interval (CI) 0.53-0.86], 0.74 for acute and subacute death (95% CI 0.61-0.87) and 0.90 for prediction of severe acute illness (95% CI 0.84-0.97). Accordingly, a Cop level >33.1 pmol/L correctly identified in-hospital death with 71% sensitivity and 74% specificity. A Cop level >13.6 pmol/L was instead associated with 89% sensitivity and 80% specificity for identifying patients with acute and severe conditions. The results of our analysis would suggest that the use of Cop may be a valuable aid in the ER for identifying patients with life-threatening conditions.