Could Serum Copeptin Level Be an Indicator of Coronary Artery Disease Severity in Patients with Unstable Angina?

This study aimed to identify the serum copeptin levels in patients diagnosed with unstable angina (UA) and evaluate the relationship between the patients' copeptin levels and angiographic severity.A total of 200 patients who were diagnosed with UA and underwent coronary angiography were included in the study. Clinical, electrocardiographic, echocardiographic, and laboratory data (high-sensitivity cardiac troponin T and copeptin levels) as well as The Global Registry of Acute Coronary Events (GRACE) 1.0 risk score were recorded upon admission. Moreover, the Synergy Between Percutaneous Coronary Intervention with Taxus and Cardiac Surgery (SYNTAX) score was calculated following coronary angiography.We isolated and defined two subgroups within our study population: group 1 included patients with non-significant coronary artery disease (CAD) (< 50% diameter stenosis, n = 105); group 2 included patients with significant CAD (≥ 50% diameter stenosis, n = 95). The number of cases with a GRACE score higher than 140 was significantly higher in group 2 than in group 1 (P < 0.001). The SYNTAX scores and copeptin levels were significantly higher in group 2 than in group 1 (P < 0.001 for both). A positive correlation was observed between the copeptin levels and SYNTAX scores (r = 0.683; P < 0.001), and the cut-off level of copeptin was 18.3 pmol/L (sensitivity of 74.7%, specificity of 83.8%, and area under the curve of 0.795).This study suggests that it may be beneficial to use conventional scoring systems and serum copeptin levels when identifying high-risk UA patients.