Preoperative Risk Factors for Postoperative Delirium in Older Patients with Cancer Undergoing Surgery: A Case–control Study

Purpose Postoperative delirium (POD) is a common complication in older patients with cancer undergoing surgery, leading to prolonged hospitalization and cognitive decline. This study examined the relationship between preoperative psychological and cognitive assessments and POD incidence in these patients. Methods This case–control study included 195 patients (≥ 65 years) undergoing elective surgery. Patients were classified into delirium (n = 53) and non-delirium (n = 142) groups based on the delirium screening tool and the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, criteria. Preoperative assessments included physical function (performance status, bedside mobility scale, functional independence measure, grip strength), fatigue (cancer fatigue scale), psychological state (hospital anxiety and depression scale [HADS-A and HADS-D], vitality index, numerical rating scale), and cognitive function (mini-mental state examination [MMSE] and frontal assessment battery). The demographic, clinical, and preoperative characteristics of the two groups were compared. Multivariate logistic regression analysis was performed to identify POD-associated factors. Results Patients with POD had lower MMSE (p < .001) and higher HADS-A (p < .001) and HADS-D (p < .001) scores. Logistic regression identified HADS-A (odd ratio [OR] 1.505; 95% confidence intervals (CI), 1.225–1.849, p < .001) and HADS-D (OR, 1.280; 95% CI, 1.085–1.510, p = .003) as independent risk factors, whereas higher MMSE scores (OR, 0.811; 95% CI, 0.719 to 0.916, p < .001) were associated with a reduced risk. Conclusions Preoperative MMSE and HADS predict POD in older patients with cancer, emphasizing the importance of cognitive and psychological assessments and the need for effective preoperative interventions.