Research Highlights:

  • States that participated in the Medicaid expansion provision of the Affordable Care Act, raising the income level to be eligible for Medicaid up to 138% of the federal poverty level, improved several measures of heart disease care for Medicaid recipients in their states.
  • In an analysis of 30 studies comparing states that chose to participate in Medicaid expansion with those that didn’t, Medicaid expansion was associated with improvement in insurance coverage for cardiac care, decreased out-of-hospital deaths, fewer socioeconomic and demographic disparities in care and increased preventive care and screening.

Embargoed until 1 p.m. CT/2 p.m. ET, Tuesday, June 20, 2023

DALLAS, June 20, 2023 — An expansion of the Affordable Care Act that extends Medicaid eligibility to more people improved patient outcomes, prevention measures and screening access, according to a review of research published today in Circulation: Cardiovascular Quality and Outcomes, a peer-reviewed American Heart Association journal.

A provision of the Affordable Care Act of 2010 extended Medicaid eligibility to all adults with incomes of up to 138% of the federal poverty level in states that elect to participate, with the federal government covering 90% of the costs. Medicaid provides health insurance coverage for people with low income, and the expansion ensures that, as of June 2023, individuals who are making less than $14,580 a year, or a family of four making less than $30,000 have access to health coverage. This includes low-wage workers, people working in jobs that don’t offer health insurance, seniors nearing retirement who have lost their health care coverage or uninsured people who make too much money to qualify for Medicaid without the expansion but too little to qualify for subsidized coverage policies in the general insurance marketplace.

“Our work adds to the growing body of evidence supporting the idea that expanding health insurance coverage results in better health outcomes,” said lead study author Ginger Y. Jiang, M.D., M.B.A., a clinical fellow in cardiovascular medicine at Beth Israel Deaconess Medical Center in Boston. “As a result, it is important for health care professionals, researchers and legislators to work together to develop policies that prioritize broadening insurance coverage to improve health for all people in America.”

More than 1 in 4 people covered by Medicaid have a history of heart disease, and many deal with multiple chronic conditions that raise the risk of heart disease – such as Type 2 diabetes, high blood pressure, high cholesterol and high triglycerides, Jiang noted.

“Expansion of Medicaid is one of the most important health policy changes over the past 10-15 years,” said senior study author Jason H. Wasfy, M.D., M.Phil., an associate professor of medicine at Harvard Medical School and director of outcomes research at the Massachusetts General Hospital Heart Center, both in Boston. “Many groups have studied Medicaid expansion and how it has affected the care of patients with heart disease, yet there was a need to synthesize results and resolve any discrepancies among study findings, which is what we intended to do with this paper.”

The researchers reviewed 30 studies, published between January 2014 and July 2022, that evaluated the association between Medicaid expansion and cardiac outcomes. Most studies (70%) used nationwide public or government data, followed by data in private registries (26.7%). The studies compared changes in outcomes before and after Medicaid expansion among people in states enrolled in Medicaid expansion and in non-participating states. The median follow-up time after Medicaid expansion was two years.

The analysis found:

  • Of the studies tracking changes in insurance coverage for cardiac treatments, 64% found improvement with Medicaid expansion.
  • Of the studies tracking changes in heart-related deaths and illness, 36% found improvement with Medicaid expansion. With Medicaid expansion, there was a decrease in out-of-hospital deaths from heart disease but no association with in-hospital deaths.
  • Of the studies tracking disparities in care across different socioeconomic and demographic groups, 37.5% found reduced disparities with Medicaid expansion.
  • Of the studies tracking preventive care, such as screening and treatment for high blood pressure, high cholesterol and Type 2 diabetes, 48% found improved preventive care with Medicaid expansion.

“Overall, it appears that expansion of Medicaid was associated with increased health insurance coverage for individuals with heart disease and improved uptake in preventive care such as screening for health concerns that impact heart health,” said Wasfy. “What is less clear is whether Medicaid expansion improved outcomes in hospital settings. Perhaps when patients are in the hospital, they tend to get recommended therapies regardless of insurance status, but then later, as outpatients without insurance, they may have many more difficulties in terms of accessing care.”

Studies included in the review are limited by a short follow-up time following Medicaid expansion, which may underestimate the eventual impact of the measure given the long-term benefits of preventive care and the delay between obtaining insurance coverage and receiving cardiac surgery or other interventions.

In addition, the study could not confirm whether differences in Medicaid expansion and non-expansion states are due to the Medicaid policy itself or other differences among the states.

The study’s other co-author is John W. Urwin, M.D. Authors’ disclosures are listed in the manuscript.

The study was funded in part by a Career Development Award to Dr. Wasfy from the American Heart Association.

Studies published in the American Heart Association’s scientific journals are peer-reviewed. The statements and conclusions in each manuscript are solely those of the study authors and do not necessarily reflect the Association’s policy or position. The Association makes no representation or guarantee as to their accuracy or reliability. The Association receives funding primarily from individuals; foundations and corporations (including pharmaceutical, device manufacturers and other companies) also make donations and fund specific Association programs and events. The Association has strict policies to prevent these relationships from influencing the science content. Revenues from pharmaceutical and biotech companies, device manufacturers and health insurance providers and the Association’s overall financial information are available here

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