Xinning Li (Boston University School of Medicine), David Veltre (Boston University School of Medicine), Paul Yi (Johns Hopkins Department of Radiology), David Sing (Boston University School of Medicine), Emily Curry (Boston University School of Medicine), Eric Smith (Boston University School of Medicine)
Hip arthroplasty (HA) is a commonly performed orthopaedic procedure. Prior studies have suggested an association between health insurance status and complications after THA in small cohorts.
The purpose of our study was to utilize a large inpatient healthcare database to evaluate the effect of patient insurance status on complications following HA.
Data was obtained from the Nationwide Inpatient Sample between 2004 and 2011 and included patients undergoing HA as determined by ICD-9-CM procedure codes. Patient demographics and comorbidities were analyzed based on insurance type. The primary outcomes were medical complications, surgical complications and mortality during the same hospitalization period. A secondary analysis was performed using a matched cohort comparing patients with Medicare versus private insurance using the coarsened exact matching algorithm. Pearson’s chi-squared test and multivariate regression were performed.
Overall, 1,011,184 patients (64.8% Medicare, 29.3% private insurance, 3.7% Medicaid or uninsured, 2.0% Other insurance) fulfilled study inclusion criteria. The majority of patients were primary total HA (64.2%) and primary hip hemiarthroplasty (29.8%), with 6% revision HA. Multivariate regression analysis showed that patients with private insurance had fewer complications (OR=0.8, p<0.001) while those with Medicaid or no insurance had more medical complications (OR=1.06, p=0.005) compared to Medicare patients (Table 1 & Figure 1). Similar trends were found for both surgical complications and mortality. The matched cohort comparing Medicare to private insurance patients showed low in-hospital complication rates (<1%). More gastrointestinal and genitourinary complications were seen in the Medicare patient population, while more CNS, peripheral vascular, wound dehiscence, and DVT were seen in the Private insurance patients. The most common complication was postoperative anemia with 23% in the Medicare and 21% in the private insurance patients (p<0.001).
Patients with Medicare, Medicaid or no insurance have higher risk of medical complications, surgical complications and mortality following hip arthroplasty. Using a matched cohort to directly compare Medicare to private insurance patients, the risk of postoperative complications are generally low, but different between the two insurance groups. The most common complication, postoperative anemia, occurs more frequently in patients with Medicare insurance.
Implications for the Patient
Significant disparities exist in THA outcomes and complications between patients with private insurance and non-private insurance. These findings have implications for patient selection for THA, as well as developing quality improvement initiatives to improve what is generally considered a high-value orthopaedic procedure.