Effect of pre-operative statin administration on delirium rate after coronary artery bypass grafting (CABG): a prospective cohort study

Background: Statins have recently been suggested to exert protective cerebral effects in patients undergoing cardiac surgery. Objective: The aim of this study was to determine the association between pre-operative statin administration and the rate of post-operative delirium (POD) in patients undergoing coronary artery bypass grafting (CABG). Methods: This prospective cohort study was conducted at Seyedoshohada Hospital (Urmia, Iran) from June 2017 through April 2018. Patients, before undergoing CABG may have two different approaches by clinicians; administrating statins vs. those who do not receive statins. Participants in this study were selected among each of the two approaches. Therefore, Group A (n=200) (exposure group) received statins 10 mg or 20 mg in the preoperative period and Group B (n=200) did not receive statins before admission to hospital. During their intensive care unit (ICU) stay, Confusion Assessment Method (CAM) was performed every 8 hours to assess delirium. The data were analyzed by STATA version 13. The rate of POD were determined across the groups using independent samples t-test and Chi-square tests. Study covariates were adjusted and the association between the outcome of delirium incidence and clinical interventions was examined using multiple logistic regression. Results: Demographic data was similar between the two groups. Of the four hundred patients analyzed, 57 patients (14.5%) had delirium at some time during their cardiovascular ICU stay; nine (4.5%) in the patients group with use of statins and forty-eight (24%) in the patients group without use of statins had POD. There was a significant difference in the occurrence of delirium across the two groups (p=0.001). Incidence of POD in patients ≥ 60 years in Group A was significantly lower than in the patients in Group B, 4.2% and 32.3% respectively (p=0.001). Conclusion: Statin Pretreatment reduces the occurrence of post-operative delirium after coronary artery bypass surgery.