Objective: To describe the association between cognitive outcome in the first postoperative week and that at three months after both off-pump and on-pump coronary bypass surgery, and to make a direct comparison of early cognitive outcome after off-pump versus on-pump surgery.
Design: Randomised trial with an additional prediction study within the two randomised groups.
Setting: Three centres for heart surgery in the Netherlands.
Patients: 281 patients, mean age 61 years.
Interventions: Participants were randomly assigned to off-pump or on-pump coronary bypass surgery.
Main outcome measures: Cognitive outcome, assessed by psychologists who administered neuropsychological tests one day before and four days and three months after surgery. A logistic regression model was used to study the predictive association between early cognitive outcome, together with eight clinical variables, and cognitive outcome after three months.
Results: Cognitive outcome in the first week after surgery was determined for 219 patients and was a predictor of cognitive decline after three months. This association was stronger in on-pump patients (odds ratio (OR) 5.24, p < 0.01) than in off-pump patients (OR 1.80, p = 0.23). Early decline was present in 54 patients (49%) after off-pump surgery and 61 patients (57%) after on-pump surgery (OR 0.73, p = 0.25).
Conclusions: In patients undergoing first time coronary bypass surgery, early cognitive decline predicts cognitive outcome after three months. Early cognitive decline is not significantly influenced by the use of cardiopulmonary bypass.