Implicit Bias in Medicare’s Comprehensive Care for Joint Replacement Model

By Inna Cintina, PhD, Lane Koenig, PhD, and Elizabeth Hamlett, BS
December 13, 2022

In a July 2022 Health Affairs Forefront blog, the Centers for Medicare & Medicaid (CMS) discussed its review of implicit bias in the Comprehensive Care for Joint Replacement (CJR) model.  For its purpose, CMS defined implicit bias as unintentional differential care and/or treatment of certain racial and ethnic beneficiaries created by an algorithm, set of rules or processes within a model. The CJR aims to reduce the costs of lower-extremity joint replacement, while maintaining or improving patient outcomes.  CMS found that financial incentives related to meeting episode-based target prices led providers to reduce costs by shifting patients to lower-cost settings (i.e., home health agencies) following joint replacement.  However, CMS cited literature that has found that Black and low-income Medicare beneficiaries tend to use skilled nursing facilities (SNFs) and inpatient rehabilitation hospitals (IRFs) more than other patients following joint replacement surgery, making them potentially more expensive than their counterparts. Because CMS did not adjust spending targets for socioeconomic factors, it concluded that participating providers may have had a disincentive to offer joint replacement to Black and low-income beneficiaries.

In this blog, we explore the root causes of disparities in joint replacement and post-acute care (PAC) use among Black beneficiaries that could lead to higher use of SNFs and IRFs.  We argue that a chain of factors leads to disparities in access and use of joint replacement treatment as well as the care setting following surgery.

Black beneficiaries and low-income populations may represent more severe cases when receiving joint replacement due to delays in accessing care

Prior to joint replacement surgery, Black patients present with more severe conditions, have more comorbidities, and, as a result, tend to be at greater risk for complications than their non-Black counterparts.  There are documented differences in preferences for the elective joint replacement treatment, accessibility, and disease progression between Black individuals and non-Black individuals.  Some studies have shown that poorer health status during surgery leads to slower and more difficult recovery.  Another study showed that Black patients undergoing an elective total hip arthroplasty were more likely to require functional assistance than White patients.  These findings are in line with observed longer hospital lengths of stay and non-home discharges following surgery for Black patients.

Factors other than financial concerns contribute to the underutilization of joint replacement among Black individuals

A study by KNG Health researchers found lower utilization of joint replacement in elderly Black individuals with osteoarthritis, particularly among Black women.  In addition, the study found that lack of familial support at home contributes to lower rates of joint replacement for certain age and gender groups.  Lack of familial support could also contribute to higher likelihood of utilizing institutional care post treatment, as these patients may need more support during recovery.  While poverty status affects the utilization of joint replacement surgeries, it does not appear to completely explain lower rates of joint replacement among Black patients relative to White patients, given that disparities were observed for  both Medicare-Medicaid eligible beneficiaries and Medicare-only patients.  Moreover, for Medicare beneficiaries whose surgical expenses are covered by Medicare, disparities are less likely to be due to financial reasons.

The low use of joint replacement by Black individuals can also be traced to differences in preferences and lack of communication of the benefits related to surgical intervention (e.g., pain relief and impact on functional improvement).  Preference-based discussions and shared decisionmaking tools, which explain the risk and benefits of surgical procedures, have been shown to increase uptake of knee replacement surgeries among Black individuals, who otherwise might have opted for conservative therapy.  Finally, disparities in utilization might be related to access and other community-specific reasons, as fewer total hip and knee replacements were conducted in hospital service areas with higher proportions of Medicare-Medicaid enrollees and Black population.

Minorities more likely to utilize institutional PAC settings, such as IRFs and SNFs

After joint replacement, Black patients use more IRFs and SNFs, rather than home health (HH) care or home without PAC.  As noted earlier, minorities may represent a sicker patient population, which would make them better candidates for institutionalized care.  Shifting patients who may benefit from institutional post-acute care to HH may have negative consequences, as these patients care needs may not be met optimally at home, leading to poorer patient outcomes.  Furthermore, not all patients referred to HH care receive that care.  Another study with KNG Health researchers found that one-third of patients referred to HH after a hospital stay did not receive HH care.  Patients with “incomplete HH care referrals” were more likely to be people of color, dual eligible, from non-rural communities, have higher prior utilization of health care, and have more comorbidities.  Since people of color and dual-eligible patients may be at a greater risk of incomplete HH referrals, any efforts to reduce cost by shifting patients to low-cost PAC settings, such as HH, have the potential to increase disparities.

Implications for policy makers and health care in general

Policy makers must recognize that baseline treatment patterns may reflect pre-existing biases and disparities in a study population.  It is essential to understand these existing disparities and the underlying causes of the inequities.  When designing value-based payment models, designers must consider these inequities and develop approaches to either reduce or, at a minimum, not acerbate them.

CMS is focused on eliminating implicit bias in its alternative payment models and reducing disparities in access to beneficial treatments and outcomes.  To be successful, CMS should move beyond just reshaping existing models that focus on the point of service but use population health approaches to reduce inequities in accessing appropriate care.

Services : Blog, Health Economics & Outcomes Research, Payment Policy & Delivery System Innovation, Quality & Performance Measurement Expertise: , , , , , , ,