Which Clinical and Patient Factors Influence the National Economic Burden of Hospital Readmissions After Total Joint Arthroplasty?

• Published in: Clinical orthopaedics and related research 2017-12, Vol.475 (12), p.2926-2937
• Main Authors: Kurtz, Steven M., Lau, Edmund C., Ong, Kevin L., Adler, Edward M., Kolisek, Frank R., Manley, Michael T.
• Format: Article
• Language: English
• Subjects: Adult; Aged; Aged, 80 and over; Arthroplasty; Arthroplasty, Replacement, Hip - adverse effects; Arthroplasty, Replacement, Hip - economics; Arthroplasty, Replacement, Knee - adverse effects; Arthroplasty, Replacement, Knee - economics; Conservative Orthopedics; Costs; Data Mining; Databases, Factual; Demography; Diagnosis-Related Groups - economics; Dislocation; Female; Fractures; Health care policy; Hospital Costs; Hospitals; Hospitals, High-Volume; Hospitals, Low-Volume - economics; Humans; Joint surgery; Length of Stay - economics; Male; Medicare - economics; Medicine; Medicine & Public Health; Middle Aged; Orthopedics; Patient admissions; Patient Readmission - economics; Postoperative Complications - economics; Postoperative Complications - therapy; Process Assessment (Health Care) - economics; Risk Assessment; Risk Factors; Sex Factors; Sports Medicine; Surgery; Surgical Orthopedics; Symposium: Learning From Large-Scale Orthopaedic Databases; Time Factors; Treatment Outcome; United States
• ISSN: 0009-921X; 1528-1132
• DOI: 10.1007/s11999-017-5244-6

Background The Affordable Care Act of 2010 advanced the economic model of bundled payments for total joint arthroplasty (TJA), in which hospitals will be financially responsible for readmissions, typically at 90 days after surgery. However, little is known about the financial burden of readmissions and what patient, clinical, and hospital factors drive readmission costs. Questions/purposes (1) What is the incidence, payer mix, and demographics of THA and TKA readmissions in the United States? (2) What patient, clinical, and hospital factors are associated with the cost of 30- and 90-day readmissions after primary THA and TKA? (3) Are there any differences in the economic burden of THA and TKA readmissions between payers? (4) What types of THA and TKA readmissions are most costly to the US hospital system? Methods The recently developed Nationwide Readmissions Database from the Healthcare Cost and Utilization Project (2006 hospitals from 21 states) was used to identify 719,394 primary TJAs and 62,493 90-day readmissions in the first 9 months of 2013 based on International Classification of Diseases, 9th Revision, Clinical Modification codes. We classified the reasons for readmissions as either procedure- or medical-related. Cost-to-charge ratios supplied with the Nationwide Readmissions Database were used to compute the individual per-patient cost of 90-day readmissions as a continuous variable in separate general linear models for THA and TKA. Payer, patient, clinical, and hospital factors were treated as covariates. We estimated the national burden of readmissions by payer and by the reason for readmission. Results The national rates of 30- and 90-day readmissions after THA were 4% (95% confidence interval [CI], 4.2%–4.5%) and 8% (95% CI, 7.5%–8.1%), respectively. The national rates of 30- and 90-day readmissions after primary TKA were 4% (95% CI, 3.8%–4.0%) and 7% (95% CI, 6.8%–7.2%), respectively. The five most important variables responsible for the cost of 90-day THA readmissions (in rank order, based on the Type III F-statistic, p