Do Medicare Accountable Care Organizations Reduce Disparities After Spinal Fracture?

National changes in health care disparities within the setting of trauma care have not been examined within Accountable Care Organizations (ACOs) or non-ACOs. We sought to examine the impact of ACOs on post-treatment outcomes (in-hospital mortality, 90-day complications, and readmissions), as well as surgical intervention among whites and nonwhites treated for spinal fractures.

We identified all beneficiaries treated for spinal fractures between 2009 and 2014 using national Medicare fee for service claims data. Claims were used to identify sociodemographic and clinical criteria, receipt of surgery and in-hospital mortality, 90-day complications, and readmissions. Multivariable logistic regression analysis accounting for all confounders was used to determine the effect of race/ethnicity on outcomes. Nonwhites were compared with whites treated in non-ACOs between 2009 and 2011 as the referent.

We identified 245,704 patients who were treated for spinal fractures. Two percent of the cohort received care in an ACO, whereas 7% were nonwhite. We found that disparities in the use of surgical fixation for spinal fractures were present in non-ACOs over the period 2009-2014 but did not exist in the context of care provided through ACOs (odds ratio [OR] 0.75; 95% confidence interval [CI] 0.44, 1.28). A disparity in the development of complications existed for nonwhites in non-ACOs (OR 1.09; 95% CI 1.01, 1.17) that was not encountered among nonwhites receiving care in ACOs (OR 1.32; 95% CI 0.90, 1.95). An existing disparity in readmission rates for nonwhites in ACOs over 2009-2011 (OR 1.34; 95% CI 1.01, 1.80) was eliminated in the period 2012-2014 (OR 0.85; 95% CI 0.65, 1.09).

Our work reinforces the idea that ACOs could improve health care disparities among nonwhites. There is also the potential that as ACOs become more familiar with care integration and streamlined delivery of services, further improvements in disparities could be realized.