Abstract
BACKGROUND: Managing pre-operative anemia is an essential element of the Enhanced Recovery After Surgery program. In developing nations, a high prevalence of pre-operative anemia and worse outcomes are predicted for patients undergoing hip arthroplasty. However, this area remains a significant research gap in these healthcare settings. PURPOSE: The study aims to determine the prevalence, related factors, and outcomes of pre-operative anemia in hip arthroplasty patients. METHODS: This retrospective observational study used descriptive statistics to determine the prevalence of pre-operative anemia and employed multivariable logistic regression to identify its associated factors. Propensity score matching (PSM) was applied to reduce confounding before outcome comparisons, with inverse probability of treatment weighting (IPTW) used as a sensitivity analysis. The primary outcome was post-operative complications, with secondary and tertiary outcomes focusing on infection conditions, length of stay, clinical symptoms, and care demands. RESULTS: The study involved 769 patients, with a pre-operative anemia prevalence of 41.1%. Pre-operative factors related independently to anemia included aging, body mass index, creatinine levels, hip fractures, hyponatremia, and atrial fibrillation. After PSM, those with pre-operative anemia had significantly higher rates of post-operative composite complications (37.6% and 25.9%, p=0.017), infection complications (22.8% and 11.2%, p=0.003), urinary tract infections (10.2% and 3.6%, p=0.017), and sepsis (14.2% and 6.1%, p=0.012). Additionally, these patients experienced post-operative anemia (89.8% vs 74.6%, p<0.001), a higher need for blood transfusions (44.7% vs 10.7%, p<0.001), and a longer post-operative length of stay (7.2 vs 6.8 days, p<0.001). These findings remained consistent after IPTW adjustment. CONCLUSION: In our setting, pre-operative anemia is highly prevalent among patients undergoing hip arthroplasty and is associated with adverse post-operative outcomes. Therefore, this study emphasizes the need to identify these patients as high risk for post-operative complications.