Objective: To investigate the relationship between postoperative delirium (POD) and postoperative cognitive dysfunction (POCD) after coronary artery bypass graft in Chinese population.
Methods: One hundred and seven patients who were referred for elective coronary artery bypass grafting (CABG) surgery were enrolled in this prospective cohort study. Baseline and perioperative variables as well as occurrence of postoperative complications were recorded. POD was diagnosed using the Confusion Assessment Method for the Intensive Care Unit twice daily during the first seven postoperative days. A neuropsychological test battery that included 7 tests with 9 subscales was administered at baseline and on the seventh day after surgery. POCD was defined using the same definition that was used in the ISPOCD1 study.
Results: The incidence of POD was 47.7% (51/107) while that of POCD was 55.3% (57/103). Multivariate Logistic regression analyses identified four independent risk factors of POD, i.e., increasing age (OR 1.174, 95% CI 1.085-1.269, P<0.001), preoperative history of diabetes mellitus (OR 4.224, 95% CI 1.543-11.563, P=0.005), occurrence of postoperative complications (OR 3.667, 95% CI 1.152-11.670, P=0.028), and prolonged duration of intensive care unit stay (OR 1.024, 95% CI 1.005-1.044, P=0.016). And two independent risk factors of POCD were identified, i.e., increasing age (OR 1.065, 95% CI 1.001-1.134, P=0.047) and prolonged duration of POD (OR 1.744, 95% CI 1.173-2.593, P=0.006).
Conclusion: POD and POCD are common cognitive complications after CABG surgery in Chinese population. Prolonged duration of POD is an independent risk factor of the occurrence of POCD.