Readmission Rates and Diagnoses Following Total Hip Replacement in Relation to Insurance Payer Status, Race and Ethnicity, and Income Status

Robert S. White, Dahniel L. Sastow, Licia K. Gaber-Baylis, Virginia Tangel, Andrew D. Fisher, Zachary A. Turnbull

Total hip replacements (THRs) are the sixth most common surgical procedure performed in the USA. Readmission rates are estimated at between 4.0 and 10.9%, and mean costs are between $10,000 and $19,000. Readmissions are influenced by the quality of care received. We sought to examine differences in readmissions by insurance payer, race and ethnicity, and income status. We analyzed all THRs from 2007 to 2011 in California, Florida, and New York from the State Inpatient Databases, Healthcare Cost and Utilization Project, Agency for Healthcare Research and Quality. Primary outcomes were readmission at 30 and 90 days after THR. Descriptive statistics were calculated, and multivariate logistic regression analysis was used to estimate adjusted odds ratio (OR) for readmissions. Statistical significance was evaluated at the < 0.05 alpha level. A total of 274,851 patients were included in the analyses. At 30 days (90 days), 5.6% (10.2%) patients had been readmitted. Multivariate logistic regression analysis showed that patients insured by Medicaid (OR 1.23, 95%CI 1.17-1.29) and Medicare (OR 1.58, 95%CI 1.44-1.73) had increased odds of 30-day readmission, as did patients living in areas with lower incomes, Black patients, and patients treated at lower volume hospitals. Ninety-day readmissions showed similar significant results. The present study has shown that patients on public insurance, Black patients, and patients who live in areas with lower median incomes have higher odds of readmission. Future research should focus on further identifying racial and socioeconomic disparities in readmission after THR with an eye towards implementing strategies to ameliorate these differences.