Dialysis path leads to improvements in health equity

Current events have demonstrated the ongoing need for health care providers to strive for more equitable delivery of care to all patients.

While such efforts can take many forms, the achievement of health equity is something the medical community can and should continue to focus. Specifically, a growing body of literature has described the profound impact that environmental and socioeconomic factors (collectively, social determinants of health [SDOH]) can have on patient outcomes. However, achieving equitable health outcomes across the socioeconomic spectrum at a national scale is a major challenge.

Dialysis and health equity

By design, dialysis has the potential to be a leader in health equity. First, dialysis treatments are broadly available in local communities, with most patients residing within 7.9 miles of a dialysis facility. That, combined with a universal payment benefit, standardized processes, socioeconomic status-agnostic service design and on-site provision of social work and dietitian support, makes dialysis a unique health care delivery model. This structure may facilitate more equitable outcomes across socioeconomic strata nationwide.

Patient-level data from the United States Renal Data System (USRDS) provide some indication that the set of standard services that define U.S. dialysis have helped to improve care and outcomes across all patients on dialysis. According to the USRDS 2020 Annual Data Report, adjusted mortality rates for prevalent dialysis patients in the United States declined from 19.8 deaths per 100 patient-years in 2008 to 16.4 deaths per 100 patient-years in 2018, a decrease of 17.3%. The relative decline was similar across racial groups; for example, adjusted mortality rates fell from 21.5 to 17.6 deaths per 100 patient-years in white patients (17.8% decrease) vs. 17.6 to 14.4 deaths per 100 patient-years in African American patients (18% decrease).

A more direct examination of how dialysis facilities perform across SDOH strata is needed to assess progress toward the equitable delivery of dialysis care nationwide. We examined the performance of dialysis facilities based on the features of the geographic areas in which these are located. This methodology assumes SDOH that exist in a small geographic region such as a county are representative of patients who receive care in those geographies and is widely used in the health care industry for such assessments.

Equity of care

There are a limited number of metrics that uniformly measure health care quality at facilities nationwide. One such measure is the CMS Star Rating System. The agency implemented this system during the past decade as a method to summarize quality of care metrics in a form that is easy for patients to understand. It has a sound methodological basis in terms of the measures included and the statistical approach for determining the rating. Dialysis facility ratings are based on nine clinical outcome measures and range from one to five stars, with five stars indicating the highest performance.

We used star ratings to assess health equity by examining the variability in star ratings across the spectrum of socioeconomic advantage. Specifically, we sought to understand if dialysis facility star rating performance is similar for facilities that serve more socioeconomically disadvantaged patients compared to those that serve more socioeconomically advantaged patients.

We considered all dialysis facilities for which 2018 star rating data were available (6,105 facilities). Given patients are likely to live near the health care facilities that they use, SDOH indicators for the population served by a given facility can be estimated based on facility location by linkage to U.S. Census data (poverty) and county health rankings (food environment index, unemployment, high school graduation rates and severe housing problems).

Of the measures available in the county health rankings data, those used in this analysis were selected as relevant representative measures addressing aspects of both the social economic and the physical environment. County-level data derived from these sources were aggregated into national-level quartiles and linked to each dialysis facility on the basis of FIPS county code. Associations between facility rating and SDOH indicators were then estimated using linear regression models.

For each socioeconomic indicator assessed, dialysis facilities achieved fairly consistent performance across the first two quartiles of each socioeconomic indicator, with a statistically significant drop-off in star ratings in the less advantaged two quartiles (see Figure). However, differences between the most- and least-advantaged quartiles were small, being less than 0.4 points on a 5-point scale in each case.

This data suggest that dialysis practiced in the United States has achieved a degree of health equity over the studied factors, but more work is required to continue to close equity gaps.

Equitable outcomes

A number of factors may have contributed to the ability of the dialysis community to make progress toward equitable outcomes on a national scale. First, dialysis centers are located in the community where the patients live and care is personalized by local health care workers. Second, the Medicare End-Stage Renal Disease Program covers most patients on dialysis, regardless of age. Third, the USRDS ensures transparency and allows for evaluation of outcomes by potential disparity strata. Lastly, CMS, in conjunction with ESRD Networks, has leveraged the dialysis facility conditions for coverage to drive improvements in the quality of care for all patients on dialysis.

The bundled payment system implemented by CMS in 2011 covers a variety of services that may not be covered in other patient populations, such as education and support from dietitians and social workers. These support services may be especially important in achieving equitable outcomes in at-risk populations. Importantly, the analysis presented here evaluates facility level performance; further studies will be needed to address whether provision of care is equitable across patients within facilities.

Conclusions

As a result of successfully scaling a complex medical procedure to a national level, providing near-universal coverage through policy and implementing quality control standards and improvement processes, the U.S. dialysis community has made advancements toward health equity. However, work remains to be done to extend these advancements to the most disadvantaged geographic regions. It is possible that further improvements in health equity may require a shift to more value-based programs, such as those suggested by the Center for Medicare and Medicaid Innovation. Such programs may allow the identification and provision of resources that are needed to improve health equity across the renal continuum.

• References:
• HHS. CMS. Medicare Program; End-Stage Renal Disease Prospective Payment System, Payment for Renal Dialysis Services Furnished to Individuals With Acute Kidney Injury, End-Stage Renal Disease Quality Incentive Program. Final rule. Fed Reg. 2019;84:60648-60809.
• Stephens JM, et al. J Rural Health.2013;doi:10.1111/jrh.12022.
• United States Renal Data System. 2020 Annual Data Report: Epidemiology of kidney disease in the United States. NIH, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, Md.
• www.countyhealthrankings.org
• www.medicare.gov/dialysisfacilitycompare

• For more information:
• Geoffrey A. Block, MD, FASN, is the associate chief medical officer and senior vice president of clinical research at U.S. Renal Care and can be reached at [email protected].
• Steven M. Brunelli, MD, MSCE, is the vice president and medical director of Health Analytics and Insights at DaVita Clinical Research and can be reached at [email protected].
• Mary Dittrich, MD, FASN, is the executive vice president and chief medical officer of U.S. Renal Care and can be reached at [email protected].
• Jeffrey Giullian, MD, MBA, is the chief medical officer at DaVita Inc. and can be reached at [email protected].
• Mahesh Krishnan, MD, MPH, MBA, is group vice president, research and development at DaVita Inc. and can be reached at [email protected].