Postoperative Delirium Following Joint Replacement in Patients With Dementia in New South Wales, Australia: A State-Wide Retrospective Cohort Study.

The objective of the current study was to investigate the variation in postoperative delirium in patients with dementia undergoing joint replacement in New South Wales (NSW) Australia public hospitals, identify factors related to its occurrence, and explore the volume-outcome relationship. The NSW Admitted Patient Data (July 2001 to June 2014) were used in this study and included patients with dementia undergoing joint replacement who were 65 or older with minor to severe comorbidities. Mixed-effect logistic models were applied to investigate hospital-level variation and factors associated with postoperative delirium. The between-hospital variability of postoperative delirium was 0.19% prior to 2008-2009 and 8.32% after 2008-2009. Hospital volume was not inversely associated with postoperative delirium rate. During 2001-2014, the incidence of postoperative delirium increased by 13% per annum (95% confidence interval [CI] 10% to 16%), while it increased by 15% per annum (95% CI 8% to 22%) after 2008-2009. An integrated approach addressing complex needs of patients with dementia may reduce the observed unwarranted variation and improve surgical outcomes. [Research in Gerontological Nursing, 13(5), 243-253.].