Temporal Trends and Severity of Postoperative Delirium in Cardiac Surgery: Insights from a Systematic Review and Meta-analysis.

Abstract

Postoperative delirium (POD) is one of the most common neurocognitive complications following cardiac surgery, typically occurring within 72 hours and leading to serious consequences, including falls, prolonged hospitalization, and increased healthcare costs. Annually, over two million cardiac surgeries, including coronary artery bypass grafting, are performed worldwide. This study systematically reviews and meta-analyzes the incidence, duration, time to onset, and severity of delirium following cardiac surgery. No previous comprehensive analysis has addressed all these outcomes, particularly regarding temporal patterns and severity of POD. A systematic review was performed following PRISMA guidelines. The studies included adult patients who underwent cardiac surgery and were assessed for delirium using validated tools. Statistical analyses included random-effects meta-analysis for incidence rates and subgroup analyses. Twenty-seven studies involving 5,126 participants from 2009 to March 2024 were included. The overall incidence of POD was 25.1% (95% confidence interval [CI]: 21.8%-28.3%), with a mean duration of 2.378 days (95% CI: 2.086-2.671), and onset occurring at 1.706 days (95% CI: 1.198-2.214). Only three studies assessed the severity of delirium, reporting a maximum Confusion Assessment Method score of 9.308 (95% CI: 7.309-11.307) on a scale of 0 to 19. Subgroup analyses were conducted to examine heterogeneity but revealed no significant differences in outcomes. Therefore, a meta-regression analysis focusing on age, surgery duration, assessment length, study design, and assessment tools was performed. The incidence and burden of POD highlight the need for regular screening and effective management strategies.