The Elixhauser Comorbidity Index as a Predictor of Disruptive Bleeding in Total Hip Arthroplasty: Impact on Outcomes and Costs

BACKGROUND: With an estimated one million cases per year anticipated by 2030, total hip arthroplasty (THA) is a popular and successful treatment for end-stage hip osteoarthritis. The objectives of this study were to: (1) measure the incidence of disruptive bleeding; (2) determine the demographics of patients and the burden of Elixhauser comorbidity related to disruptive bleeding; and (3) assess the effect of disruptive bleeding on health care utilization (inpatient costs, hospital lengths of stay, and 90-day readmission rates). METHODS: In this cohort study, patients who had primary THA in 2019 were identified using a national health care database. Multivariate logistic regressions were used to examine possible associations with disruptive bleeding after patients were grouped by Elixhauser Comorbidity Index (ECI), which ranged from 0 to ≥ 6. Both 95% confidence intervals (CIs) and odds ratios (ORs) were presented for every ECI. Generalized linear models were used to assess the effects of disruptive bleeding on hospital lengths of stay, 90-day readmission rates, and overall expenses. RESULTS: Disruptive hemorrhage occurred in 6,586 (6.0%) of the 109,482 patients receiving THA. Higher bleeding risk was linked to women and Medicare coverage (P < 0.01). For instance, the risks of disruptive bleeding rose from OR = 1.48 (95% CI 1.23 to 1.78, P < 0.001) for ECI = 2 to OR = 3.81 (95% CI 2.85 to 5.10, P < 0.001) as the comorbidity burden increased. Disruptive bleeding was linked to higher overall expenses ($34,700 versus $23,500 for ECI > 6; P < 0.001), longer hospital stays (6.0 days for ECI ≥ 6; P < 0.001), and higher 90-day readmissions (18.5 versus 10.2% for ECI = 5; P < 0.001). CONCLUSIONS: Patients who had higher comorbidity burdens are more likely to experience disruptive hemorrhage following THA, which is linked to worse short-term results and noticeably higher resource utilization.