Racial and Ethnic Disparities in Utilization Rate, Hospital Volume, and Perioperative Outcomes After Total Knee Arthroplasty.

BACKGROUND: Previous studies of racial disparities in total joint replacement, particularly total knee arthroplasty, in the U.S. have predominantly focused on disparities between blacks and whites and were limited to Medicare patients or veterans, populations that are not representative of the entire U.S. POPULATION: We sought to study racial disparities in the utilization of total knee arthroplasty, the use of high-volume hospitals, and total knee arthroplasty outcomes, including mortality and complications, using all-payer databases.
METHODS: We analyzed data from 8 years and 8 racially diverse states in the State Inpatient Databases (SID). Patient race was categorized according to the SID as white, black, Hispanic, Asian, Native American, and mixed race. Both crude and adjusted racial and/or ethnic disparities were evaluated.
RESULTS: In comparison with whites (4.65 per 1000 population per year), black (3.90), Hispanic (3.71), Asian (3.89), Native American (4.40), and mixed-race (3.69) populations had lower rates of total knee arthroplasty utilization (p < 0.0001). After risk adjustment, the rate of total knee arthroplasty utilization was significantly lower for blacks (odds ratio [OR] = 0.87 [95% confidence interval (CI), 0.85 to 0.89]; p < 0.0001), Hispanics (OR = 0.76 [95% CI, 0.68 to 0.83]; p < 0.0001), Asians (OR = 0.83 [95% CI, 0.78 to 0.89]; p < 0.0001), Native Americans (OR = 0.87 [95% CI, 0.81 to 0.93]; p < 0.0001), and mixed race (OR = 0.84 [95% CI, 0.79 to 0.90]; p < 0.0001) compared with the rate for whites. Lower rates of total knee arthroplasty utilization for blacks, Hispanics, and mixed-race groups became worse over the years. Patients from minority groups were less likely to undergo total knee arthroplasty in high-volume hospitals than were whites. Moreover, the rates of mortality were significantly higher for blacks (OR = 1.52 [95% CI, 1.17 to 1.97]; p = 0.0017), Native Americans (OR = 6.52 [95% CI, 4.63 to 9.17]; p < 0.0001), and mixed-race patients (OR = 4.35 [95% CI, 3.24 to 5.84]; p < 0.0001). Blacks (OR = 1.08 [95% CI, 1.01 to 1.15]; p = 0.01) and mixed-race patients (OR = 1.17 [95% CI, 1.001 to 1.36]; p = 0.04) had higher rates of complications than whites.
CONCLUSIONS: Minorities had lower rates of total knee arthroplasty utilization but higher rates of adverse health outcomes associated with the procedure, even after adjusting for patient-related and health-care system-related characteristics. Utilization rates were based on overall population as the proportion of the population with osteoarthritis requiring arthroplasty is unknown. Future studies that consider specific patient-level information with psychosocial and behavioral factors are needed. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.