After five consecutive years of coverage gains, progress toward reducing the number of uninsured Americans stalled in 2016, according to a government report that underscores the stakes as Republicans try to roll back Barack Obama's law.
The Centers for Disease Control and Prevention estimated that 28.6 million people were uninsured last year, unchanged from 2015. The uninsured rate was 9 percent, an insignificant difference from 9.1 percent in 2015.
The numbers, released Tuesday, suggest that the two main components of the Affordable Care Act, or ACA, were reaching their limits in Obama's final year as president.
Premiums for private insurance were about to jump, and 19 states continued to refuse the ACA's Medicaid expansion. The number of uninsured could start climbing again under some of the policies now being considered by President Donald Trump and congressional Republicans.
"To increase coverage, you would have to see more states take up the Medicaid expansion."
The politically unpopular GOP bill passed narrowly by the House would limit Medicaid financing and curtail subsidies for many consumers buying their own private policies. Republicans also would repeal the requirement that most Americans carry health insurance or risk fines.
The legislation would lead to an estimated increase of 24 million uninsured people within 10 years, according to congressional analysts. Under "Obamacare," there are 20 million fewer uninsured since 2010.
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"It's disappointing that it's stalled out," said health economist Gail Wilensky, a Republican. "The real question is, will we be able to keep the gains that we have made?" Critical of the ACA and co-author of an alternative plan by GOP policy experts, Wilensky nonetheless supports the goal of expanding coverage. She's concerned about the impact of the House bill on Medicaid, the federal-state program for low-income and disabled people.
The latest numbers come from CDC's National Health Interview Survey, which is considered an authoritative source, and publishes findings earlier than the Census Bureau. The survey's estimates for 2016 were based on data for nearly 97,500 people.
The report validates a trend other major surveys have noted. For example, the Gallup-Healthways Well-Being Index found that the uninsured rate for U.S. adults edged up slightly during the first three months of this year, a period for which there's yet no publicly available CDC data.
"It looks like we are kind of sticking a landing and holding on to the gains," said Katherine Hempstead, who directs research on health insurance at the nonpartisan Robert Wood Johnson Foundation. "To increase coverage, you would have to see more states take up the Medicaid expansion, and some reforms to increase take-up in the individual (private) market."
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Could the number of uninsured start rising again? Absolutely, say both Wilensky and Hempstead.
"This release is really timely because it just helps everybody focus on what's at stake," said Hempstead.
The report found a significant increase in the percentage of people under age 65 covered last year through government-sponsored insurance markets like HealthCare.gov. About 11.6 million (4.3 percent) had marketplace insurance in the last three months of 2016, compared with 9.1 million (3.4 percent) in the same period the previous year.
"It's news because people need to know we seem to have reached a plateau."
States that expanded Medicaid were more effective at reducing the number of uninsured. Of the 16 states with adult uninsured rates significantly lower than the nation as a whole, 15 expanded Medicaid. In that group, only Wisconsin had not extended coverage for low-income people.
Conversely, of the nine states that had significantly higher uninsured rates, only New Mexico expanded Medicaid.
The CDC numbers do not reflect any changes directly attributable to Trump, who took office this year on Jan. 20.
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During the campaign and since then, the president has made some expansive promises about health insurance, talking of coverage for everybody and much more affordable premiums and deductibles. But Trump has also embraced a GOP bill that would make more people uninsured, even if it fulfills his campaign promise to repeal "Obamacare." And he's threatened to stop paying subsidies that reduce out-of-pocket costs such as deductibles for people with modest incomes.
Hillary Clinton, whom Trump defeated, had promised to increase government assistance for private insurance costs, and also work to convince holdout states to expand their Medicaid programs.
"This is really pre-election activity" reflected in the CDC survey, said Wilensky. "It's news because people need to know we seem to have reached a plateau." Whether that will look the same a year from now is unclear, she added.