Medicaid Expansion May Reduce Access Gaps in Kidney-Related Care, Study Suggests

While Medicaid is designed to provide health insurance for low-income Americans, states have flexibility within federal guidelines to design their programs. There is limited information on how differences in Medicaid coverage influence chronic disease care. Now a study shows that states with broader Medicaid coverage have lower incidences of kidney failure and smaller insurance-related gaps in access to kidney disease care. The Journal of the American Society of Nephrology findings point to the potential benefits of Medicaid expansion on the prevention and management of a chronic disease.

Chronic disease care is a major source of rising health care expenditures, and access to care for uninsured individuals with a chronic disease has eroded over the last decade. This may change for many patients with the implementation of the Affordable Care Act, which expands Medicaid coverage to adults with incomes below 133% of the federal poverty level; however, not all states are expected to participate in this expansion.

Examining the care of patients approaching end stage renal disease (ESRD) may provide insights into the potential effect of Medicaid expansion on chronic disease care. Affecting more than 350,000 nonelderly Americans, ESRD comes with a cost of $10 billion per year. While all Americans with ESRD can qualify for Medicare coverage, those who are younger than 65 years must rely on other sources of insurance or pay out of pocket to cover pre-ESRD care. Research indicates that an estimated 10% of adults with nondialysis-dependent chronic kidney disease are uninsured.

Using national data, Manjula Tamura, MD, MPH, of the VA Palo Alto Health Care System and Stanford University, led a team that assessed the relation between the extent of state Medicaid coverage and access to care among nonelderly adults approaching ESRD and whether that relationship differed based on patients’ insurance status. “We wanted to determine whether states with broader Medicaid coverage of low-income non-elderly adults had a lower incidence of ESRD and better access to pre-ESRD care,” Tamura said. “We also wanted to determine whether broad state Medicaid coverage benefited uninsured adults in addition to those receiving Medicaid.”

The researchers identified 408,535 adults aged 20 to 64 years who developed ESRD from 2001 through 2008. Medicaid coverage among low-income nonelderly adults living in different states ranged from 12.2% to 66.0%. Broader Medicaid coverage among low-income nonelderly adults was associated with a lower incidence of ESRD: for each additional 10% of the low-income nonelderly population covered by Medicaid, there was a 1.8% decrease in ESRD incidence.

Low-income nonelderly adults with ESRD who were on Medicaid had better access to care in states with broader Medicaid coverage: For a 50-year-old white woman, the access gap to being put on the kidney transplant waiting list between Medicaid and private insurance decreased by 7.7 percentage points in high vs. low Medicaid coverage states. Similarly, the access gap to transplantation decreased by 4.0 percentage points and the access gap to peritoneal dialysis decreased by 3.8 percentage points. Finally, broader Medicaid coverage was associated with some spillover benefits for uninsured adults with ESRD, but these were small and not consistently observed.

“Our study suggests that Medicaid expansion among low-income nonelderly adults could support efforts to prevent kidney failure and improve access to kidney disease care,” Tamura said.

The findings are consistent with other recent studies that found lower rates of adult mortality and delayed care in states that expanded Medicaid coverage, and improvements in mental health among newly enrolled Medicaid beneficiaries.

In an accompanying editorial, Raj-nish Mehrotra, MD, and Larry Kessler, ScD, of the University of Washington, Seattle, stated that the researchers’ work “highlights the intricate web of health insurance, access to care, and ESRD. Their study is timely as a social experiment is unfolding in this country that will allow us to further examine the association between Medicaid coverage and health care outcomes.” They noted that such a population-level analysis needs corroborative evidence to identify the causes for the links that were found, though. For example, improved treatment for diabetes and hypertension, which are the most common underlying causes of ESRD, may have considerable impacts on the association of more generous state Medicaid coverage with lower incidences of ESRD.

Because a 2012 Supreme Court judgment made the Affordable Care Act’s Medicaid expansion optional for states, the current period of differential Medicaid coverage will allow researchers to study a variety of questions related to access to care and health gains for the most vulnerable segments of the population.

“In the case of ESRD, we strongly recommend that detailed data also be collected concerning the intermediate markers or indicators, such as diabetes and hypertension control, to understand the nature of the impact of the provision of expanded coverage,” wrote Mehrotra and Kessler.

The article, entitled “State Medicaid Coverage, ESRD Incidence, and Access to Care,” is online at http://jasn.asnjournals.org/.

The editorial, entitled “Health Insurance, Access to Care, and ESRD: An Intricate Web,” is online at http://jasn.asnjournals.org/.