Impact of Dementia on Perioperative Complications in Elderly Patients Undergoing Total Knee Arthroplasty: A Retrospective National Inpatient Sample Database Study

Background Dementia is widely recognized as a factor that influences the outcomes of total knee arthroplasty (TKA). However, recent studies have not fully elucidated the effects of dementia on perioperative medical and surgical complications, as well as in-hospital resource utilization. The objective of this study is to evaluate the specific impact of dementia on perioperative outcomes in elderly patients undergoing TKA. Methods Data on elderly patients undergoing TKA were extracted from the National Inpatient Sample database (2010-2019). Patients were categorized into a dementia group and a non-dementia group. Propensity score matching (PSM) was employed to control for differences in demographics, hospital characteristics, and comorbidities. Multivariate logistic regressions were conducted to evaluate perioperative outcomes. Results From 2010 to 2019, a group of 344,200 patients undergoing TKA was identified, among whom 6761 individuals (2.0%) were diagnosed with dementia. Following PSM, dementia remained an independent predictor for several perioperative outcomes, including urinary tract infection (aOR = 2.001, 95%CI = 1.561-2.564, P < 0.0001), pneumonia (aOR = 2.043, 95%CI = 1.244-3.355, P = 0.005), postoperative delirium (aOR = 5.854, 95%CI = 4.418-7.758, P < 0.0001), acute hemorrhagic anemia (aOR = 1.229, 95%CI = 1.128-1.340, P < 0.0001), prolonged hospital stay (aOR = 1.966, 95%CI = 1.785-2.165, P < 0.0001), and increased total healthcare charges (aOR = 1.122, 95%CI = 1.037-1.215, P = 0.004). Conclusion Dementia is independently associated with an increased risk of perioperative complications after TKA, underscoring the importance of tailored perioperative care for elderly patients with dementia.