A randomized clinical trial evaluated whether preoperative cognitive training reduces postoperative delirium in patients undergoing coronary artery bypass grafting (CABG) surgery. The study enrolled 218 patients across three hospitals in southeastern China, with 208 patients included in the final analysis. Participants were randomly assigned to either routine care or cognitive training, which involved 10 hours of online cognitive exercises designed to enhance memory, attention, and other cognitive functions. Cognitive training was associated with a 57% reduction in delirium incidence compared to routine care (adjusted odds ratio 0.43; 95% CI 0.23-0.77; P = .007). Significant differences were also observed in the severity and duration of delirium. Secondary outcomes, including postoperative cognitive dysfunction and 30-day mortality, did not show significant differences between groups. The study suggests that preoperative cognitive training may help prevent delirium in CABG patients, though results should be considered exploratory and further research is needed. The trial was conducted in a hospital setting, with patients receiving cognitive training for 6 hours on average, which was less than the 10 hours requested. The study highlights the potential benefits of cognitive training in reducing delirium, but acknowledges limitations such as possible confounding factors and the need for larger trials. The findings indicate that preoperative cognitive training may be an effective strategy for reducing delirium in CABG patients, but more research is needed to confirm these results.A randomized clinical trial evaluated whether preoperative cognitive training reduces postoperative delirium in patients undergoing coronary artery bypass grafting (CABG) surgery. The study enrolled 218 patients across three hospitals in southeastern China, with 208 patients included in the final analysis. Participants were randomly assigned to either routine care or cognitive training, which involved 10 hours of online cognitive exercises designed to enhance memory, attention, and other cognitive functions. Cognitive training was associated with a 57% reduction in delirium incidence compared to routine care (adjusted odds ratio 0.43; 95% CI 0.23-0.77; P = .007). Significant differences were also observed in the severity and duration of delirium. Secondary outcomes, including postoperative cognitive dysfunction and 30-day mortality, did not show significant differences between groups. The study suggests that preoperative cognitive training may help prevent delirium in CABG patients, though results should be considered exploratory and further research is needed. The trial was conducted in a hospital setting, with patients receiving cognitive training for 6 hours on average, which was less than the 10 hours requested. The study highlights the potential benefits of cognitive training in reducing delirium, but acknowledges limitations such as possible confounding factors and the need for larger trials. The findings indicate that preoperative cognitive training may be an effective strategy for reducing delirium in CABG patients, but more research is needed to confirm these results.