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.
Arthroplasty, Replacement, Hip* ; Comorbidity ; Delirium* ; Dislocations ; Hematoma ; Humans ; Inpatients ; Length of Stay ; Logistic Models ; Male ; Myocardial Infarction ; Pneumonia ; Postoperative Complications ; Pulmonary Embolism ; Renal Insufficiency ; Risk Factors ; Seroma ; Thrombosis ; Veins ; Wounds and Injuries

BACKGROUND: The number of patients with systemic lupus erythematosus (herein, lupus) undergoing total hip arthroplasty (THA) or total knee arthroplasty (TKA) is increasing. There is disagreement about the effect of lupus on perioperative complication rates. We hypothesized that lupus would be associated with higher complication rates in patients who undergo elective primary THA or TKA. METHODS: Records of more than 6.2 million patients from the National Inpatient Sample who underwent elective primary THA or TKA from 2000 to 2009 were reviewed. Patients with lupus (n = 38,644) were compared with those without lupus (n = 6,173,826). Major complications were death, pulmonary embolism, myocardial infarction, stroke, pneumonia, and acute renal failure. Minor complications were wound infection, seroma, deep vein thrombosis, hip dislocation, wound dehiscence, and hematoma. Patient age, sex, duration of hospital stay, and number of Elixhauser comorbidities were assessed for both groups. Multivariate logistic regression models using comorbidities, age, and sex as covariates were used to assess the association of lupus with major and minor perioperative complications. The alpha level was set to 0.001. RESULTS: Among patients who underwent THA, those with lupus were younger (mean age, 56 vs. 65 years), were more likely to be women (87% vs. 56%), had longer hospital stays (mean, 4.0 vs. 3.8 days), and had more comorbidities (mean, 2.5 vs. 1.4) than those without lupus (all p < 0.001). In patients with THA, lupus was independently associated with major complications (odds ratio [OR], 1.4; 95% confidence interval [CI], 1.1 to 1.7) and minor complications (OR, 1.2; 95% CI, 1.0 to 1.5). Similarly, among patients who underwent TKA, those with lupus were younger (mean, 62 vs. 67 years), were more likely to be women (93% vs. 64%), had longer hospital stays (mean, 3.8 vs. 3.7 days), and had more comorbidities (mean, 2.8 vs. 1.7) than those without lupus (all p < 0.001). However, in TKA patients, lupus was not associated with greater odds of major complications (OR, 1.2; 95% CI, 0.9 to 1.4) or minor complications (OR, 1.1; 95% CI, 0.9 to 1.3). CONCLUSIONS Lupus is an independent risk factor for major and minor perioperative complications in elective primary THA but not TKA.