How Does Iron Deficiency Anemia Impact Outcomes following Revision Total Hip Arthroplasty?

PURPOSE: Studies have shown the prevalence of iron deficiency anemia (IDA) increasing worldwide, and currently the literature is limited on the impact of IDA on outcomes following revision total hip arthroplasty (RTHA). Therefore, the purpose of this study was to determine whether IDA patients undergoing RTHA have longer: 1) in-hospital lengths of stay (LOS); 2) medical complications; and 3) costs of care. MATERIALS AND METHODS: A retrospective query of a nationwide administrative claims database was performed. Using Boolean command operations, the study group consisted of all patients in the database undergoing RTHA with IDA; whereas, patients without IDA served as controls. To reduce the effects of confounding, study group patients were matched to controls in a 1:5 ratio by age, sex, and medical comorbidities yielding 92,948 patients with (n=15,508) and without (n=77,440) IDA undergoing revision THA. A P-value less than 0.001 was considered statistically significant. RESULTS: IDA patients were found to have significantly longer in-hospital LOS (5 days vs. 4 days, P<0.0001). Additionally, the study showed IDA patients were found to higher incidence and odds of (73.84% vs. 11.77%, OR 5.04, P<0.0001) 90-day medical complications. IDA patients also incurred high 90-day episode of care costs ($25,597.51 vs. $20,085.70, P<0.0001). CONCLUSION: After adjusting for age, sex, and medical comorbidities this study of over 92,000 patients demonstrated IDA is associated with longer in-hospital LOS, complications, and costs of care. Future studies should compare the duration and severity of IDA on outcomes.