Copeptin in patients with acute myocardial infarction and newly detected glucose abnormalities - A marker of increased stress susceptibility? A report from the Glucose in Acute Myocardial Infarction cohort

Objective: To characterize copeptin levels and to explore its prognostic importance in patients with acute myocardial infarction with newly detected glucose abnormalities. Methods: Copeptin was measured in 166 patients with acute myocardial infarction without known diabetes and in 168 age- and gender-matched controls. Participants were classified as having normal glucose tolerance or abnormal glucose tolerance (impaired glucose tolerance + type 2 diabetes mellitus) by oral glucose tolerance test. Study participants were followed over a decade for major cardiovascular event (acute myocardial infarction/stroke/congestive heart failure/cardiovascular death), cardiovascular and total death. Results: Median copeptin level was higher in patients (10.5 pmol/L) than controls (5.9 pmol/L; p < 0.01). Patients with abnormal glucose tolerance had higher copeptin (12.2 pmol/L) than those with normal glucose tolerance (7.9 pmol/L; p < 0.01) but levels of copeptin did not differ in controls with abnormal glucose tolerance or normal glucose tolerance. Copeptin predicted major cardiovascular events [n = 64; hazard ratio = 1.15 (1.01-1.32; p = 0.04)], cardiovascular mortality [n = 29; hazard ratio = 1.24 (1.06-1.46; p = 0.01)] and total death [n = 51; hazard ratio = 1.21 (1.05-1.40; p = 0.01)] in unadjusted Cox regression analyses in the patient cohort. In controls, copeptin predicted major cardiovascular events [n = 26; hazard ratio = 1.17 (1.01-1.36; p = 0.03)]. Conclusion: Copeptin levels are highest among acute myocardial infarction patients with glucose disturbances and predict an adverse prognosis in unadjusted analyses. These findings imply that raised copeptin reflects stress rather than acting as a pathogenic factor for glucose abnormalities.