The Anthem logo hangs at the health insurer's corporate headquarters in Indianapolis. (Michael Conroy/AP)

Health insurer Anthem is pulling out of Ohio's Affordable Care Act marketplace, a move that leaves people in a fifth of the state's counties facing the prospect of having zero insurers selling individual marketplace plans in their area next year.

Ohio had one of the country's most competitive insurance marketplaces. In 2016, there were 17 insurers selling on the exchange in Ohio, with four offering plans state-wide. In 2017, there are still 11 insurers participating in the exchange, but 20 counties had only one insurer, according to the Ohio Department of Insurance.

In its decision to leave the state's exchange, Anthem cited lack of certainty around billions of dollars in federal payments that help reduce out-of-pocket costs for lower-income Americans. It also pointed to "an increasing lack of overall predictability."

As part of the Affordable Care Act, the federal government pays billions of dollars to insurers to help lower-income Americans cover their deductibles and out-of-pocket health-care costs. The Trump administration has not been clear about whether it will continue making those payments next year, as they're tied up in an ongoing legal challenge.

Anthem's statement also emphasized "continual changes in federal operations, rules and guidance" and a "shrinking individual market."

Anthem's withdrawal from Ohio's exchange — markets created by the law where people who buy individual insurance plans can take advantage of federal subsidies — will leave 10,500 people from Ohio in 18 counties with no choices, according to Ohio's Department of Insurance.

It also raises the deeper question of whether Anthem might be contemplating a larger exit from other states' Affordable Care Act marketplaces. Unlike many states where insurers are weighing whether to withdraw, Ohio's insurance marketplace has been competitive and performed better financially than the national average last year, according to an analysis by the Kaiser Family Foundation.

"It seems this is more motivated by political and regulatory uncertainty, and it could be a sign that Anthem would exit nationally," said Cynthia Cox, associate director for the Program for the Study of Health Reform and Private Insurance at the Kaiser Family Foundation. "If that is the case, that could leave hundreds of thousands of people without any insurer option. This could be the tip of the iceberg."

Leslie Porras, a spokeswoman for Anthem, said in an email that the company remains in "active dialogue" with states and regulators.

"Regulations and deadlines for making the decision regarding our participation vary by state and we intend to continue our dialogue with regulators until that time," Porras said.

Anthem has already signaled its intent to participate next year in exchanges in some other states, including Virginia and Connecticut.

"For more than seven decades, Anthem Blue Cross and Blue Shield has served consumers in the individual market and throughout that time our commitment remained the same: to provide access to affordable, quality healthcare," the company's statement said. "As the individual marketplace continues to evolve, Anthem will continue to advocate solutions that will stabilize the market to allow us to return to a more robust presence in the future."

The last few months have seen a trickle of news on insurers exiting markets or requesting big rate increases, with more announcements expected as deadlines approach in other states. Republicans have pointed to insurer exits or massive rate increases as evidence that the Affordable Care Act is dead. Democrats, meanwhile, have blamed Republicans for refusing to provide companies the regulatory clarity they need to continue providing insurance to millions of Americans.

"Obamacare continues to collapse," White House press secretary Sean Spicer said at the White House briefing Tuesday, pointing to Anthem's decision in Ohio.

The political blame game is likely to continue and intensify in coming weeks as insurers announce more decisions, either to curtail or withdraw from markets or to seek big rate increases.

“This is the latest example of President Trump and Republicans in Congress destabilizing health-care coverage for the American people. Their constant attacks and intentional efforts to create uncertainty are pushing some plans to withdraw from the marketplace and others to raise premiums," Rep. Sander M. Levin (D-Mich.) said in a statement.

In other states, insurers have made requests for large rate increases. Others face the prospect of having zero option for consumers. In Iowa and Nebraska, a small midwestern insurer called Medica has been catapulted into the national spotlight as potentially the last insurer in both states' marketplaces, although that company has not announced a final decision about whether to participate in either state. In Missouri, Blue Cross and Blue Shield of Kansas City announced in late May that it would leave 32 counties in Kansas and Missouri.

"Without true competition and choice in the market, we will never be able to lower health care costs for families and small businesses. This is one more reason why the status quo on health care is unsustainable. The Affordable Care Act has failed to meet the promises that were made to Ohio families," Sen. Rob Portman (R-Ohio) said in a statement.

Juliet Eilperin contributed to this story.

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