title: Risk factors of delirium in patients undergoing total knee arthroplasty.
abstract: Although postoperative delirium is a complicated disorder in elderly individuals, no study has been examined the risk factors associated with perioperative comorbidities and clinical laboratory data while specifically focusing on only total knee arthroplasty (TKA). In the present retrospective study, we aimed to evaluate the incidence and perioperative risk factors of postoperative delirium after TKA. Between April 2009 and May 2013, 287 patients (365 knees) aged >65 years who had undergone primary TKA were enrolled. These patients were assigned to the delirium group of 11 patients (11 knees) or the non-delirium group of 276 patients (354 knees). The incidence of delirium among the patients was 3.1% (11/365). Univariate logistic regression analysis indicated that a history of dementia, older age, lower body mass index (BMI) level, and a postoperative day 3 blood urea nitrogen (BUN) level of >14.9 mg/dL were risk factors. However, multivariate logistic regression analysis indicated that a history of dementia (adjusted odds ratio [AOR]: 10.4, [1.09, 100]), older age (AOR: 1.15, [1.01, 1.31]), and a postoperative day 3 BUN level of >14.9 mg/dL (AOR: 4.76, [1.15, 19.7]) were independent risk factors. Based on our findings, we believe that the surgeons should be careful to avoid the postoperative delirium and ensure the appropriate management for patients who have these risk factors.
authors.affiliation: Department of Orthopaedic Surgery, College of Medicine, Hanyang University, Seoul, Republic of Korea.
authors.forename: Kyu Sung
authors.initials: KS
authors.lastname: Chung
authors.affiliation: Department of Orthopaedic Surgery, College of Medicine, Hanyang University, Seoul, Republic of Korea.
authors.forename: Jin Kyu
authors.initials: JK
authors.lastname: Lee
authors.affiliation: Department of Orthopaedic Surgery, College of Medicine, Hanyang University, Seoul, Republic of Korea.
authors.forename: Jin Sik
authors.initials: JS
authors.lastname: Park
authors.affiliation: Department of Orthopaedic Surgery, College of Medicine, Hanyang University, Seoul, Republic of Korea. Electronic address: chhchoi@hanyang.ac.kr.
authors.forename: Choong Hyeok
authors.initials: CH
authors.lastname: Choi
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee / Q000523:psychology*; D003693:Delirium; D003704:Dementia / Q000453:epidemiology* / Q000209:etiology; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D009017:Morbidity / Q000639:trends; D020370:Osteoarthritis, Knee / Q000601:surgery; D011183:Postoperative Complications; D056910:Republic of Korea / Q000453:epidemiology; D012189:Retrospective Studies; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D015996:Survival Rate / Q000639:trends
keywords: Delirium; Risk factor; Total knee arthroplasty