Oe S, et al. - In this retrospective study, researchers recognized the risk factors of post-adult spinal deformity (ASD) surgery delirium, including nutritional state before surgery. They included 319 consecutive patients, divided into a group of 30 delirium (group D) or 289 non-delirium (group ND) who had ASD surgery. A significant difference was found between groups in age, serum albumin, operative time, prognostic nutritional index (PNI) score, and controlling nutritional status index (CONUT) score. Investigators found that postoperative delirium risk factors following ASD surgery were PNI less than 49.7 and age more than 68.5 years. Satisfactory informed consent needs to be provided by patients having ASD surgery who are past these preoperative cut-off values, and they should be advised of delirium.