Oh TK, et al. - After total knee arthroplasty (TKA) under spinal anesthesia, experts gauged the relationship between perioperative statin use and occurrence of delirium. The electronic medical records of patients who underwent TKA under spinal anesthesia at a single tertiary care hospital between January 2005 and October 2017 were retrospectively reviewed. Findings suggested a probable association of continuous perioperative statin use with a significantly lower risk of delirium following TKA under spinal anesthesia. The most effective statin for POD prevention was simvastatin. After administering simvastatin, the POD incidence decreased by 37%, and 79% respectively.