Preoperative Factors Associated With Postoperative Delirium in Older Patients With Cancer Undergoing Surgery: Retrospective Cohort Study

BACKGROUND: Post-operative delirium (POD) is a common complication in older patients with cancer undergoing surgery, leading to prolonged hospitalisation and cognitive decline. This study examined the relationship between pre-operative psychological and cognitive assessments and POD incidence in these patients. METHODS: This retrospective cohort 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. Pre-operative assessments included grip strength; fatigue (Cancer Fatigue Scale); psychological state (Hospital Anxiety and Depression Scale [HADS-A and HADS-D]); vitality index; numerical rating scale; cognitive function (Mini-Mental State Examination [MMSE] and frontal assessment battery) and physical function (performance status and bedside mobility scale). The demographic, clinical and pre-operative characteristics of the two groups were compared. Multivariate logistic regression analysis was performed to identify POD-associated factors. RESULTS: Compared with the non-delirium group, patients with POD had lower pre-operative MMSE scores and higher pre-operative HADS-A and HADS-D scores (all p < 0.001). Logistic regression identified HADS-A (odds ratio [OR], 1.505; 95% confidence interval [CI], 1.225-1.849; p < 0.001) and HADS-D (OR, 1.280; 95% CI, 1.085-1.510; p = 0.003) as factors independently associated with POD, whereas higher MMSE scores (OR, 0.811; 95% CI, 0.719-0.916; p < 0.001) were associated with a lower likelihood of POD. CONCLUSIONS: Pre-operative MMSE and HADS were associated with POD in older patients with cancer, emphasising the importance of cognitive and psychological assessments in perioperative care.