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Study: ACA and Medicaid Expansion Drops Number of Uninsured and Lowers Disparities in Some States

States with Medicaid Expansion After ACA Implemented Saw Access to Care Disparities Diminish Dramatically

doctor goes over a chart with a male patient in exam room

The number of uninsured patients dropped in nearly all states after the implementation of the Affordable Care Act (ACA). However, the largest decreases were seen in states where Medicaid coverage was expanded (also known as expansion states) compared to states without Medicaid expansion (also known as nonexpansion states), according to an American Cancer Society study recently published in the JAMA Oncology medical journal.

Researchers found disparities - among minorities, patients living in high-poverty, or rural areas - were significantly lowered or eliminated in Medicaid expansion states but remained high in nonexpansion states. They reviewed data from nearly 2.5 million adult patients under the age of 65 in 40 states who received a cancer diagnosis between 2010 and 2014.

The Affordable Care Act (ACA), also known as Obamacare, became a law in March 2010, but wasn’t fully implemented until January 1, 2014. The study authors only analyzed data from 2014, the first full year of Medicaid expansion. 

The ACA and Medicaid expansion led to fewer people without health insurance, said Xuesong Han, PhD, the lead study author and senior principal scientist in the surveillance and health services research group of the American Cancer Society. Han and her co-authors compared states that increased Medicaid eligibility to states that didn’t. They discovered that after the ACA implementation:

  • The percentage of uninsured patients decreased in almost all states and reached a record low of 9% among all Americans in 2014. 
  • The largest decreases in the number of uninsured people were in expansion states. For example, before Obamacare, Kentucky had an uninsured population of 8.3% that dropped to 2.1% in 2014, after the state adopted Medicaid expansion. Neighboring Tennessee chose not to expand Medicaid coverage and saw its 9.1% uninsured rate only drop to 7.6%.

The researchers found disparities remained high in nonexpansion states, and in some cases were getting worse. “This suggests that Medicaid expansion may be an effective way to reduce health disparities based on race and ethnicity, yearly income, and rural locations,” Han says.

Earlier studies showed a narrowing in racial/ethnic disparities among the general population in both Medicaid expansion states and nonexpansion states. “But in our study, which was specific to patients with cancer, we saw the narrowing of disparities only in Medicaid expansion states,” Han said.

“People with health insurance are more likely to get an early cancer diagnosis and then receive the right treatments compared to the uninsured. Having health insurance also affects how well a person will do after being treated for cancer. For one thing, they live longer,” Han said. 

The Basics of Medicaid and Medicaid Expansion

Federal law requires all states to offer Medicaid as a health insurance option for people who meet certain rules. One of the rules is the Medicaid income limit. That’s how much money a person can make a year and still qualify for Medicaid based on the number of people in a family, age, parent status, and state. Each state sets its own Medicaid income limits. The limit is based on a percentage of the federal poverty level (FPL). In 2018, for example, the FPL for an individual is $12,140 and a family of 4 is $25,100 a year.  

The ACA offers federal help to fund the cost for states to increase eligibility to 138% of the FPL. Expansion states are those that have passed laws to expand health coverage through Medicaid. Nonexpansion states do not currently have laws that increase eligibility, but many are working to make changes that could greatly affect access to Medicaid.

Before the ACA and Medicaid expansion, people who lived in states where income levels had to be very low to qualify for Medicaid coverage were more likely to be uninsured, have more limited access to care, receive less preventive care, and have higher out-of-pocket costs. Han said, “the widening disparity in the percentage of uninsured patients between nonexpansion and expansion states will likely make the inequalities in access to care and health outcomes even greater in the future.”

Early stage cancer diagnoses increased slightly in Medicaid expansion states. How quickly cancer is diagnosed is important. Some cancers can be found early, when they may be easier to treat and before they have had a chance to grow and spread.

In expansion states, Han’s research revealed a slight shift toward earlier diagnoses for all types of cancer combined. “We need more data from a longer period to understand how an increase in the number of cancer patients insured by Medicaid may affect cancer treatment, survival, and costs of care,” Han says. 

“Like everyone, my family has been affected by cancer. I have seen the importance of needing health insurance and having access to care, and I understand the unique challenges of our health care system. Researchers at the ACS can help provide evidence about ways to improve cancer care and health outcomes, which can lead to changes in health care policy and laws. And that’s why research is so important,Han says.