Predictive value of early postoperative copeptin after cardiac surgery: A two-centre prospective cohort study

BACKGROUND Patients undergoing cardiac surgery are at increased risk for postoperative complications, making early postoperative risk evaluation crucial. Recent studies have shown that copeptin, a neurohumoral marker, is associated with major adverse events after noncardiac surgery. However, data on its role after cardiac surgery are scarce. OBJECTIVE Primary aim of this study was to analyse the association of early postoperative copeptin levels with adverse events after cardiac surgery. DESIGN Observational, prospective cohort study. SETTING Two German tertiary healthcare centres. Enrolment took place between March 2021 and August 2022. PATIENTS Adults undergoing elective on-pump cardiac surgery were included. MAIN OUTCOME MEASURES Main exposure was early postoperative copeptin. Primary outcome was new-onset disability 1 year after surgery, as defined by a World Health Organization Disability Assessment Schedule 2.0 (WHODAS 2.0) score of ≥16% or an increase of ≥5% in case of pre-operative disability. RESULTS 295 out of 363 prospectively enrolled patients were included in the final analysis (28.8% female, median [IQR] age 64 years, [56 to 71]. Fifty-four patients (18.3%) developed new-onset disability and 3.4% (10/295) died within 1 year. Logistic regression analysis showed an adjusted odds ratio (aOR) of 2.35 (95% confidence interval, 'CI', 1.17 to 4.72) for the association between elevated copeptin and new-onset disability. The discrimination of copeptin for new-onset disability was weak and did not improve risk stratification when added to the pre-operative EuroSCORE II and postoperative troponin (ROC AUCEuroSCOREII+troponin+copeptin = 0.685, 95% CI 0.61 to 0.76; ROC AUCEuroSCOREII+troponin = 0.678, 95% CI 0.59 to 0.76, DeLong test: P = 0.82). DeLong test: P = 0.82). CONCLUSION Early postoperative copeptin is independently associated with new-onset disability at 1 year after cardiac surgery. Due to weak discrimination for new-onset disability routine measurement of copeptin cannot be recommended. TRIAL REGISTRATION Clinicaltrials.gov identifier: NCT04877795.