RENEE MONTAGNE, HOST:
One of the great hopes for the Affordable Care Act was that it would bring down trips to emergency rooms, trips that are hugely expensive for hospitals. The theory was that people who don't have health care coverage end up in emergency rooms because they can't afford regular medical care.
Under Obamacare, about four million more of the poorest Americans are eligible for the newly expanded Medicaid, and a new study published in the journal Science has an ominous warning: Giving people Medicaid appears to increase, rather than decrease their use of hospital emergency rooms.
NPR's Julie Rovner reports.
JULIE ROVNER, BYLINE: The findings were pretty straightforward, said Amy Finkelstein. She's an economics professor at MIT, and one of the study's authors.
AMY FINKELSTEIN: What we found is that Medicaid coverage increases emergency department use both overall, and for a broad range of types of visits, conditions and subpopulations, including visits for conditions that may be most readily treatable in primary care settings.
ROVNER: In other words, visits to the emergency departments for things that aren't emergencies. This is exactly what policymakers hoped to avoid by giving people health insurance. The idea is that they will seek lower cost and more appropriate care in doctor's offices instead. And that increase in ER care was fairly significant, Finkelstein noted.
FINKELSTEIN: Medicaid increased the number of emergency department visits by about .41 visits, which is about 40 percent.
ROVNER: Now, this is perhaps were it would be good to point out that this isn't just any study. This is the third major paper from something called the Oregon Health Insurance Experiment. It was a rare opportunity to create a randomized, controlled experiment, the gold standard of scientific research. It came about almost by accident, thanks to Oregon's decision in 2008 to expand Medicaid by lottery. The result, said Finkelstein...
FINKELSTEIN: You have, literally, by construction, made the people with and without insurance identical, on average, except for the fact that some have insurance and some don't. You've literally randomized the allocation of insurance coverage.
ROVNER: Thus, they could compare people with and without insurance almost equally. The first paper from the research team was mostly positive. It found that people who got Medicaid coverage were more likely to use health services in general, less likely to suffer from depression, and less likely to suffer financial problems related to medical bills than those who remained uninsured. The second paper was more equivocal. It found no measurable health benefits in the Medicaid group for several chronic conditions, including hypertension, high cholesterol and diabetes. It's not clear that the emergency room results will translate directly, nationwide. The study only lasted 18 months, and the population is more white and more urban than the rest of the nation. But that's not stopping critics of the Medicaid expansion. Michael Cannon heads health policy for the libertarian Cato Institute. He says he's not all that surprised by the findings.
MICHAEL CANNON: When you make emergency room care free to people, they consume more of it. They consume 40 percent more of it, even as they're consuming more preventive care. And so one of the main arguments for how Obamacare was going to reduce health care costs is just flat-out false.
ROVNER: Cannon says the study will likely further hurt President Obama's credibility for vowing that expanding Medicaid would help get people out of emergency rooms. But what's likely to bother the administration even more, he says, is what it may do to the half of the states that have yet to adopt the Medicaid expansion.
CANNON: This study is going to make it less likely that the 25 states that decided not to expand Medicaid are going to change their minds and expand Medicaid.
ROVNER: Perhaps ironic, however, is that this study doesn't come as much as a surprise to those people who actually Medicaid programs around the country.
KATHLEEN NOLAN: It is not something that is unexpected, and not something that we're not prepared for.
ROVNER: Kathleen Nolan is director of state policy for the National Association of Medicaid Directors. She says most states are already working to help people get care in more appropriate settings.
NOLAN: Things like nurse-advice lines, trying to work with the community clinics and other community providers to expand hours and make sure that people who are working two and three jobs can get access to primary care after hours and on the weekends.
ROVNER: Unlike private insurance, Medicaid doesn't deter emergency room use by charging people more. But the key to getting health costs down for all patients, she says, is educating people about where they can go instead when it's not actually an emergency. Julie Rovner, NPR News, Washington.
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