Objective: Postoperative delirium (POD) is a common, but severe complication in elderly patients undergoing surgery for colorectal cancer, but the prevalence and potential risk factors for POD were not well established. Therefore, a meta-analysis was preformed to clarify the prevalence and risk factors of POD in patients undergoing surgery for colorectal cancer.
Methods: PubMed, Embase, and the Cochrane Library were systematically searched on August 2019. Studies were included if they reported the prevalence and risk factors of POD in patients undergoing colorectal cancer surgery. The guidelines for critically appraising studies of prevalence or incidence of a health problem were used to assess the quality of included studies. Pooled odds ratios (ORs) for individual risk factors were estimated using the Mantel-Haenszel methods in random effect model. Sensitive analyses based on different inclusion criteria were conducted to explore whether the current meta-analysis was enough credible and robust.
Results: Seventeen studies totaling 4472 patients undergoing colorectal cancer surgery were included. The pooled prevalence of POD is 14% (95% CI = 12-17%). Twelve significant risk factors were identified in pooled analysis including older age (OR = 1.10), sex (OR = 1.87), history of psychiatric disease (OR = 6.47), comorbidities (OR = 2.17), prognostic nutritional index (OR = 1.12), physical status (OR = 1.27), American Society of Anesthesiologists Score (ASA Scores) (OR = 1.65), history of alcohol abuse (OR = 2.23), postoperative pain management (OR = 1.91), perioperative blood transfusion (OR = 2.37), cognitive status (OR = 1.91), and lower serum level of albumin (OR = 0.58).
Conclusions: POD is a frequent complication in patients undergoing surgery with colorectal cancer. Several risk factors including history of psychiatric disease, transfusion, comorbidities, male gender, and old age were significant predictors for POD.
Keywords: Coloretal cancer; Delirium; Meta-analysis; Prevalence; Risk factor.