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On a recent afternoon at his office in Hartford, Conn., Dr. Doug Gerard examines a patient complaining of joint pain. Gerard, an internist, checks her out, asks her a few questions about her symptoms and then orders a few tests before sending her on her way.

For a typical quick visit like this, Gerard could get reimbursed $100 or more from a private insurer. For the same visit, Medicare pays less — about $80. And now, with the new private plans under the Affordable Care Act, Gerard says he would get something in between, but closer to the lower Medicare rates.

That’s not something he’s willing to accept.

“I cannot accept a plan [in which] potentially commercial-type reimbursement rates were now going to be reimbursed at Medicare rates,” Gerard says. “You have to maintain a certain mix in private practice between the low reimbursers and the high reimbursers to be able to keep the lights on.”

Three insurers offered plans on Connecticut’s ACA marketplace in 2014, and Gerard is only accepting one. He won’t say which, but he will say it pays the highest rate to doctors.

“I don’t think most physicians know what they’re being reimbursed. Only when they start seeing some of those rates come through will they realize how low the rates are they agreed to.”

Gerard’s decision to reject two plans is something officials in Connecticut are concerned about. If reimbursement rates to doctors stay low in Obamacare plans, more doctors could reject those plans. And that could mean that people will get access to insurance, but they may not get access to a lot of doctors.

That worries Kevin Counihan, who runs Connecticut’s health insurance marketplace.

“I think it could lead potentially to this kind of distinction that there are these different tiers of quality of care,” Counihan says.

His agency recently approved rules geared at getting more providers into plans on the exchange. The goal is to make sure that everyone gets good care regardless of their income.

He doesn’t want the impression left that someone who gets a subsidy to buy ACA coverage will get inferior care. “That’s been something, at least in our state, that we’re trying to work against. And the carriers are, as well,” Counihan says.

All three of the insurers on Connecticut’s exchange were asked to comment. Two declined. One agreed. Ken Lalime is the CEO of Healthy CT — an insurance co-op. He says insurers face a real challenge figuring out how to pay doctors enough but also keep consumer premiums low.

“Every time you increase payments to providers, you have to offset that with increased reimbursements from the consumer,” says Lalime. “So there’s this balance between how much do you want to cost to provide that service and how much you can pass along in your premiums rates. It’s a balancing act.”

Healthy CT may have missed the balance – just 3 percent of the exchange’s consumers bought the co-op’s insurance in 2014. Lalime says he also thinks low reimbursement rates are forcing some doctors to decide against accepting insurance under the Affordable Care Act.

Dr. Bob Russo is sure of it. He’s a radiologist and he’s also the president-elect of the Connecticut State Medical Society. He says that the low rates and administrative burdens that come along with the ACA could make it a financial loser.

“You get what you pay for,” Russo says. “If you can’t convince [doctors] that they’re not losing money doing their job, then it’s a problem. And they haven’t been able to convince people of that.”

He, like Counihan, worries about creating a tiered health care system. He says, think about Medicaid. Before a recent rise in rates, it paid doctors even less than Medicare, so many stopped accepting Medicaid patients.

“There’s no question that Medicaid, under its old rates, wasn’t working. So, have we just invented a new Medicaid that kind of slid the scale up a little more to make access a little more?” Russo says.

The experience of these doctors is a good reminder that the Affordable Care Act is more than a thought exercise in health care. It’s happening. And here’s another reminder: open enrollment for 2015 begins in just over three months.