Preoperative anxiety predicted the incidence of postoperative delirium in patients undergoing total hip arthroplasty: a prospective cohort study

BACKGROUND: Delirium was characterized with a series of symptoms of a sudden onset of disturbances in attention, a loss in memory loss and defects in other cognitive abilities that were also appeared in the syndrome of anxiety. Even though there are overlapped clinical symptoms existed in anxiety and delirium, the relationship between anxiety and delirium was still unclear. The propose of this study was to investigated the effect of preoperative anxiety on postoperative delirium. METHODS: Three hundred and seventy-two adults undergoing total hip arthroplasty were enrolled from October 2019 to May 2020 in the study. The preoperative anxiety was measured with the Hospital Anxiety and Depression Scale-Anxiety (HADS-A). The participants were allocated into anxiety group (HADS-A≧7) and non-anxiety group (HADS-A < 7). The primary outcome was the incidence of the postoperative delirium assessed with the Confusion Assessment Method (CAM). The secondary outcomes were the duration and the severity of delirium evaluated with the Memorial Delirium assessment Scale (MDAS). The risks of delirium were also evaluated with logistic regression analysis. RESULTS: There were 325 patients enrolled in the end, 95 of whom met the criteria for anxiety. The incidence of delirium was 17.8% in all participants. The patients with anxiety had a higher incidence of delirium than the non-anxiety patients (25.3% vs. 14.8%, odds ratio (OR) = 0.51, 95% confidence interval (CI) = 0.92-0.29, p = 0.025). However, no significant differences were found in the duration and the severity of the delirium between the above two groups. The age, alcohol abuse, history of stroke, scores of the HADS-A, and education level were considered to be predictors of delirium. CONCLUSIONS: The preoperative anxiety predicted the incidence of the postoperative delirium in total hip arthroplasty patients. The related intervention may be a good point for delirium prophylaxis. TRIAL REGISTRATION: It was registered at Chinese Clinical Trial Registry ( www.chictr.org.cn ) with the name of "the effect of preoperative anxiety on the postoperative cognitive function" ( ChiCTR1900026054 ) at September 19, 2019.