Interventions to prevent postoperative delirium in elderly cancer patients should be targeted at those undergoing nonsuperficial surgery with special attention to the cognitive impaired patients.

Aims: The aim of this study was to determine risk factors for postoperative delirium (POD) in elderly cancer patients.

Methods: This study was an observational multicentre retrospective study performed in the University Medical Center Groningen and Medical Center Leeuwarden, the Netherlands. Patients over 65 years of age undergoing elective surgery for a solid tumour were included. The main outcome was POD. Medical records were screened for POD using a standardized instrument. The risk factors considered were: age, gender, severity of the surgical procedure, comorbidity, American Society of Anaesthesiologists (ASA) score and 15 items suggestive for frailty as measured with the Groningen Frailty Indicator (GFI). To examine an association between the risk factors and the development of POD, univariate and multivariate logistic regression analysis was performed to estimate odds ratios (ORs) and 95% confidence intervals (CIs).

Results: We reviewed 251 medical records. Forty-six patients developed POD (18.3%). Preoperative cognitive functioning (as measured by the item cognition of the GFI) (OR: 23.36; 95% CI: 5.33-102.36) and severity of the surgical procedure were identified as independent risk factors for POD; intermediate (OR: 15.44, 95% CI: 1.70-140.18) and major surgical procedures (OR: 45.01, 95% CI: 5.22-387.87) significantly increased the risk for POD as compared to minor surgery.

Conclusions: Preoperative cognitive functioning and the severity of the surgical procedure are independent risk factors for POD in elderly undergoing elective surgery for a solid tumour.