Predicting postoperative delirium severity in older adults: The role of surgical risk and executive function

• Published in: International journal of geriatric psychiatry 2019-07, Vol.34 (7), p.1018-1028
• Main Authors: Lindroth, Heidi, Bratzke, Lisa, Twadell, Sara, Rowley, Paul, Kildow, Janie, Danner, Mara, Turner, Lily, Hernandez, Brandon, Brown, Roger, Sanders, Robert D.
• Format: Article
• Language: English
• Subjects: Aged; Aged, 80 and over; aging; Blood pressure; Cognitive ability; Cohort Studies; Delirium; Delirium - epidemiology; Delirium - etiology; Delirium - psychology; Executive function; Executive Function - physiology; Female; Geriatric psychiatry; Health risk assessment; Humans; Incidence; Linear Models; Male; Middle Aged; perioperative; Postoperative Complications - epidemiology; Postoperative Complications - etiology; Postoperative Complications - psychology; Prediction models; Predictive Value of Tests; Prospective Studies; risk; Risk Factors; severity; Statistical analysis; Surgery; Surgical Procedures, Operative - adverse effects; Tobacco
• ISSN: 0885-6230; 1099-1166
• DOI: 10.1002/gps.5104

Objectives Delirium is an important postoperative complication, yet predictive risk factors for postoperative delirium severity remain elusive. We hypothesized that the NSQIP risk calculation for serious complications (NSQIP‐SC) or risk of death (NSQIP‐D), and cognitive tests of executive function (Trail Making Tests A and B [TMTA and TMTB]), would be predictive of postoperative delirium severity. Further, we demonstrate how advanced statistical techniques can be used to identify candidate predictors. Methods/Design Data from an ongoing perioperative prospective cohort study of 100 adults (65 y old or older) undergoing noncardiac surgery were analyzed. In addition to NSQIP‐SC, NSQIP‐D, TMTA, and TMTB, participant age, sex, American Society of Anesthesiologists (ASA) score, tobacco use, surgery type, depression, Framingham risk score, and preoperative blood pressure were collected. The Delirium Rating Scale‐R‐98 (DRS) measured delirium severity; the Confusion Assessment Method (CAM) identified delirium. LASSO and best subsets linear regression were employed to identify predictive risk factors. Results Ninety‐seven participants with a mean age of 71.68 ± 4.55, 55% male (31/97 CAM+, 32%), and a mean peak DRS of 21.5 ± 6.40 were analyzed. LASSO and best subsets regression identified NSQIP‐SC and TMTB to predict postoperative delirium severity (P