The Association of Delirium with Perioperative Complications in Primary Elective Total Hip Arthroplasty

BACKGROUND: Our goal was to determine whether postoperative delirium is associated with inpatient complication rates after primary elective total hip arthroplasty (THA). METHODS: Using the National Inpatient Sample, we analyzed records of patients who underwent primary elective THA from 2000 through 2009 to identify patients with delirium (n = 13,551) and without delirium (n = 1,992,971) and to assess major perioperative complications (acute renal failure, death, myocardial infarction, pneumonia, pulmonary embolism, and stroke) and minor perioperative complications (deep vein thrombosis, dislocation, general procedural complication, hematoma, seroma, and wound infection). Patient age, sex, length of hospital stay, and number of comorbidities were assessed. We used multivariate logistic regression to determine the association of delirium with complication rates (significance, p < 0.01). RESULTS: Patients with delirium were older (mean, 75 ± 0.2 vs. 65 ± 0.1 years), were more likely to be male (56% vs. 52%), had longer hospital stays (mean, 5.7 ± 0.07 vs. 3.8 ± 0.02 days), and had more comorbidities (mean, 2.8 ± 0.03 vs. 1.4 ± 0.01) (all p < 0.001) versus patients without delirium. Patients with delirium were more likely to have major (11% vs. 3%) and minor (17% vs. 7%) perioperative complications versus patients without delirium (both p < 0.001). When controlling for age, sex, and number of comorbidities, delirium was independently associated with major and minor complications (odds ratio, 2.0; 95% confidence interval, 1.7 to 2.3). CONCLUSIONS: Delirium is an independent risk factor for major and minor perioperative complications after primary elective THA.