Predictive value of monocyte-to-albumin ratio, red cell distribution with-to-albumin ratio, hemoglobin-to-albumin ratio, leukocyte-to-albumin ratio, and platelet-to-albumin ratio for 14-day readmission following primary total knee arthroplasty.

Total knee arthroplasty (TKA) is a frequently performed surgery for restoring function in patients with severe knee osteoarthritis. TKA is associated with significant healthcare costs, partly due to complications leading to readmissions. This study aimed to identify biomarkers predictive of readmission after TKA. Data of adult patients who underwent primary TKA between 2014 and 2022 extracted from the Chang Gung Medical Research Database were retrospectively reviewed. Associations between the monocyte-to-albumin ratio (MAR), red cell distribution with (RDW)-to-albumin ratio (RAR), hemoglobin-to-albumin ratio (HAR), leukocyte-to-albumin ratio (LAR), and platelet-to-albumin ratio (PAR) with 14-day readmission were determined using univariate and multivariable regression analyses. A score termed the 'MAR-LAR-PAR' score was developed using the combination of these 3 markers, and its prognostic value was assessed. Data from 1,137 patients were included. Elevated MAR (adjusted odds ratio [aOR] = 1.77, 95% confidence interval [CI]: 1.08-2.89, p = 0.022), LAR (aOR = 1.59, 95% CI: 1.02-2.45, p = 0.039), and PAR (aOR = 1.88, 95% CI: 1.12-3.15, p = 0.016) were significantly associated with increased risk of 14-day readmission. The highest MAR-LAR-PAR score (score = 3) was significantly associated with 14-day readmission compared to score = 0 (aOR = 4.24, 95% CI: 1.91-9.44, p < 0.001). This study highlights the potential of MAR, LAR, PAR, and the score based on their combination, as significant predictors of short-term readmission following TKA. Incorporating these biomarkers into preoperative assessment may help determine the risk of readmission, and provide additional care for these patients.