President Obama's executive order preventing the deportation of up to 5 million undocumented immigrants won't preclude all of them from getting affordable health coverage. But it remains to be seen just how many will be presented with that option.
Even if a good amount do get insurance, the health, social and economic costs from having the remaining immigrants effectively locked out of health coverage will remain a problem, say advocates and analysts. And some of those costs—including visits to emergency rooms that aren't paid by insurance—could end up getting passed along to the general public, they noted.
Undocumented immigrants, who currently comprise one in every six people in the United States without health insurance, by 2017 are projected to make up 1 in 4 such uninsured people, said Stephen Zuckerman, co-director of the Health Policy Center at the Urban Institute.
Zuckerman noted that it's not because there will be more undocumented immigrants without insurance. Instead, he said, it's because there will be significantly more currently uninsured people overall getting insured in the coming years through Obamacare insurance plans and from Medicaid, particularly in states that have expanded eligibility for Medicaid to include more people.
But both those options will essentially be blocked to the people subject to Obama's order last week, which lifts the threat of deportation and will give those people the ability to work legally in the U.S.
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The White House has indicated it will not allow such undocumented people access to federal subsidies that help most Obamacare enrollees afford policies sold on government-run insurance exchanges. And those people will also be barred by federal law from enrolling in Medicaid, the joint federal-state program that covers poor people.
"This issue of health coverage has been separated from their legal status and the ability to work," Zuckerman said. "And that's going to leave a large number of people without coverage, and without the ability to get coverage either through Medicaid or the subsidies in the marketplace."
That decision to separate health coverage out of the equation echoes a similar decision in 2013 by the Obama administration when it deferred deportation for young undocumented immigrants said they could not benefit from Obamacare subsidies, said Shannon Erwin, state policy director at the Massachusetts Immigrant and Refugee Advocacy Coalition.
"It was a political decision, and not really a health policy-informed decision," said Erwin, pointing out that the Obamacare exchanges were due to launch later that same year.
"I would hope there would be an an opportunity to re-open that conversation," said Erwin, who noted that health coverage is "a top concern" among immigrants.
But Derrick Morgan, vice president for economic freedom and opportunity of the conservative Heritage Foundation, said that while, "I think the administration would like" to expand subsidies to those affected people, it shouldn't do so.
"The president promised that illegal immigrants would not receive funding for Obamacare," Morgan said. The Heritage Foundation, he said, opposes having undocumented workers receive health coverage from government-sponsored or government-subsidized programs.
"They're here unlawfully, and the American taxpayer and the American citizens are the ones paying for these benefits, and these subsidies should not be going to those that are here illegally," Morgan said.
That said, the people covered by Obamas order will have several avenues for health coverage as they become eligible for work permits.
"More people will have jobs," noted Claudia Calhoon, senior health specialist with with the New York Immigration Coalition. "They will have more financial stability because they no longer will be in the shadows."
With some of those job, people will be offered employer-sponsored insurance, Calhoon said. They will also have the option of buying unsubsidized individual insurance outside the Obamacare exchanges, at the least, although Calhoon noted such "off-exchange" plans can be much more expensive than the ones sold on the exchanges.
"It will be very important to get the word out to people so they understand what benefits are available to them," she said. "Educating immigrant communities about what options do exist, and safety services for people who are uninsured, will be important.
But it's not clear how many of the immigrants subject to Obama's order will be able to buy—and able to afford—health coverage through their jobs or in the individual health plans, said Samatha Artiga, director of the Disparities Policy Project at the Kaiser Family Foundation.
"We do know, historically, that immigrants have been more likely to have low-wage job and be in industries that do not provide health-care coverage to workers," said Artiga.
And even if they are offered coverage through their employer, "In many cases, that's unaffordable," she said.
Artiga said Obama's order could alleviate the fears of being deported that have kept some of the affected undocumented immigrants from enrolling their U.S.-born children in Medicaid and CHIP health insurance programs that those kids are eligible for due to their citizenship status.
"From past research and experience, that has always been a big barrier for enrolling children in those mixed-status families," she said.
"But I think the broader issue is that individuals remain without access to affordable health coverage options, so many of them may remain uninsured."
But that doesn't mean they will stay out of the hospital.
Uninsured undocumented immigrants, along with other uninsured Americans who visit the emergency room and get other hospital services despite being unable to pay for their care, in 2012 generated nearly $46 billion in uncompensated care costs at 4,999 U.S. hospitals in 2012, the last year data was available, according to the American Hospital Association.
Those costs, equal to 6.1 percent of total hospital expenses, end up being covered by a federally funded program, by extra charges to those with insurance, or by the hospitals themselves.
While the AHA doesn't have data on how much of those costs are due to undocumented immigrants, they can be considerable in individual cases.
Dr. Julia Koehler, a pediatrician at Boston Children's Hospital, told CNBC about how an undocumented Brazilian immigrant had previously sought her help after incurring a back injury he suffered while trying to lift an older, heavier stranger who had slipped and fallen on some ice on a sidewalk.
For more than two weeks the immigrant, a father of three, had avoided going to the doctor because he lacked insurance, said Koehler, a Harvard Medical School assistant professor who volunteers at a clinic that serves immigrants.
"He ended up with an emergent injury to his spinal cord, which was a prolapse of the disc into the spinal canal," Koehler said. When he was properly diagnosed by "an excellent neurosurgeon," Koehler said, the man was told he had more than a 50 percent risk of paralysis.
"He was going to lose control of his feet, his bladder and his bowel, and not be able to work anymore because he didn't have health insurance," Koehler said.
Fortunately, the man's surgery at Brigham and Women's Hospital in Boston was a success, and he made a full recovery, she said. But the surgery itself cost "tens of thousands of dollars," which he was unable to pay, and which the hospital absorbed.
While the man's story has a happy ending, Koehler said in other cases, breadwinner in immigrant families are hurt on the job or get sick elsewhere, and then are left temporarily or permanently unable to support their families, which can in turn lead to health issues for them as well, and them becoming an economic burden to hospitals and taxpayers.
Even an immigrant going without a flu shot because of lack of insurance can lead to significant costs for others, she said.
"If you don't have health insurance and you have low income, it is very unlikely that you will come up with the money to buy a flu shot," Koehler said. "So the unimmunized person will then possibly expose other vulnerable people, perhaps asthmatics, young infants, older people."
"Health insurance should be available regardless of immigration status, because, again, it goes beyond the health of the affected individuals, and it goes to the health of the whole family and the whole community," she said.