• Press Release

Comprehensive Care Program Helped Reduce Some Racial Disparities after Hip and Knee Replacement, Researchers Find

  • New York, NY
  • (June 01, 2022)

Reductions in some outcome disparities for Black patients were observed after the launch of a “bundled care” Medicare program aimed at improving care for patients undergoing hip or knee replacement surgery, according to findings by a team of researchers from the Icahn School of Medicine at Mount Sinai. The results are reported in The Journal of Bone & Joint Surgery.

The gap between hospital readmission rates for Black and white patients after hip or knee replacement surgery narrowed after the introduction of Medicare's Comprehensive Care for Joint Replacement (CJR) Model, as did the gap in the amounts of some related Medicare payments. The researchers said they were unable to determine whether the model caused the reductions, but identified bundle design as a potential novel strategy to target racial disparities.

Using nationwide Medicare claims data, the researchers analyzed disparities between Black and white patients undergoing total hip or knee replacement surgery, before and after the rollout of the CJR Model in 2016. Under the CJR Model, health care organizations receive a single "bundled" payment for all services throughout an episode of care—from the initial hospitalization to 90 days postoperatively—providing incentives to reduce costs while improving quality of care.

The study included data on nearly 1.5 million hip or knee replacement surgeries performed from 2013 to 2018. About five percent of patients were Black.

The analysis showed substantial racial differences in patient characteristics, outcomes, and Medicare payments, both before and after implementation of the CJR Model. As a group, Black patients had higher rates of other health problems, received more blood transfusions, spent more days in the hospital, and were more likely to be discharged to an institution such as a skilled nursing facility rather than being sent directly home.

The CJR program led to improvements in several key outcomes, some of which differed by race. After adjustment for other factors, patients who were managed under the CJR approach had reductions in length of hospital stay, complication rate, risk of hospital readmission within 90 and 180 days, discharge to institutional care, and Medicare payments to skilled nursing facilities, and some of these improvements were greater among Black patients than white patients. In particular, Black patients had larger reductions in 90-day and 180-day hospital readmission rates, as well as in Medicare payments related to skilled nursing facilities.

The greater benefits among Black compared to white patients suggest that the CJR program has improved some pre-existing racial disparities. "These observed racial differences may represent true 'disparities' as some may not be attributable to clinical factors and may be directly associated with poorer outcomes," the researchers write.

“This is an important finding as it provides insights on how to effectively reduce these disparities that we know are widespread, not just in orthopedics, but in medicine in general,” said Calin Moucha, MD, Chief of Adult Reconstruction and Joint Replacement Surgery at The Mount Sinai Hospital and lead author on the study.

"These results indeed seem promising, but we do have to consider alternative perspectives and explanations of our results,” said Jashvant Poeran, MD, PhD, Director of Mount Sinai’s Center for Clinical and Outcomes Research and co-author on the study. “For example, although the effects on readmission rates are promising, the difference in payments for outpatient care—where we saw lower Medicare payments for Black patients—may also indicate potential under-utilization of post-discharge care in certain subgroups."

The researchers noted that their study could not demonstrate a causal relationship between the CJR Model and the observed improvements in patient outcomes, but wrote that together with some previous reports about outcomes after introduction of the CJR Model, the new findings "support the notion of adapting and leveraging the bundled payment program design to reduce disparities in [total hip and knee replacement] care and outcomes."

"A first step toward reducing racial differences that represent disparities is to understand the sources of these disparities," said Dr. Poeran. The authors call for further studies to evaluate the potential of bundled payment models to reduce racial disparities, and the mechanisms by which they do so.


About the Mount Sinai Health System

Mount Sinai Health System is one of the nation’s leading integrated academic health systems and one of the largest in the New York metropolitan area. Its comprehensive system includes seven hospitals, more than 400 outpatient practices, over 600 research and clinical laboratories, the Icahn School of Medicine at Mount Sinai, the Graduate School of Biomedical Sciences, and the Mount Sinai Phillips School of Nursing. Together, the Health System comprises approximately 48,000 employees, more than 9,000 physicians, and 8,600 nurses.

As a leading learning health system, Mount Sinai combines clinical expertise with scientific discovery to improve patient care while training the next generation of health care and biomedical leaders. The Health System provides care across every stage of life, from prenatal care through geriatrics, while advancing personalized medicine through artificial intelligence, data science, and biomedical research.

Mount Sinai is consistently recognized among the nation’s leading academic health systems for patient care, research, and education. The Mount Sinai Hospital is ranked No. 1 in New York by Newsweek and No. 5 on the magazine’s World’s Best Hospitals list. The Icahn School of Medicine at Mount Sinai ranks No. 11 among U.S. medical schools and No. 1 among freestanding medical schools for National Institutes of Health funding, reflecting the strength of its scientific enterprise and leadership in biomedical research.