The impact of postoperative agitated delirium on dementia in surgical patients

Abstract

This study investigates the association between postoperative agitated delirium and the risk of dementia in patients who were cognitively intact before undergoing major inpatient surgery. The study included inpatients aged 20 years or older who underwent major surgery requiring general, epidural, or spinal anaesthesia and hospitalization for over one day in Taiwan between 2008 and 2018. Patients were categorized into two groups based on the presence or absence of postoperative agitated delirium. Propensity score matching was conducted to balance various covariates known to influence dementia risk. The final analysis included 10 932 patients (5466 in each group). Multivariate Cox regression analysis was performed to assess the risk of dementia, and incidence rates and incidence rate ratios were calculated. After Propensity score matching, the study cohort comprised 5467 patients without postoperative agitated delirium and 5467 patients with postoperative agitated delirium. In the multivariate Cox regression analysis, the adjusted hazard ratio for dementia were 1.26 (95% confidence intervals, 1.08-1.46; P = 0.003) in the postoperative agitated delirium group compared to the no postoperative agitated delirium group. The incidence rates of dementia was significantly higher in patients with postoperative agitated delirium (97.65 versus 70.85 per 10 000 person-years), with an incidence rate ratio of 1.21 (95% CI: 1.04-1.40). Our study demonstrates a substantial rise in dementia incidence linked to postoperative agitated delirium. These findings stress the need for effective prevention and management strategies. Addressing this issue emerges as a vital clinical approach to reduce subsequent dementia risk, with broad implications for enhancing overall perioperative patient outcomes.

Keywords: PSM; dementia; incidence rate; postoperative agitated delirium.

Graphical Abstract

Figure 1

Kaplan–Meier cumulative incidence curves of dementia in patients undergoing non-cardiac major surgery with and without postoperative agitated delirium. Statistical significance was assessed using a stratified log-rank test (P < 0.001). (A) Before propensity scores match. (B) After propensity scores match.