Some long Covid patients face big medical bills and denied insurance claims. How to navigate coverage.

In June 2021, 32-year-old Alyssa Maness was diagnosed with POTS, a nervous system disorder that her doctors believe was triggered by Covid.

POTS, or postural orthostatic tachycardia syndrome, caused numbness throughout her arms and legs, a pins-and-needles sensation and sudden drops in her heart rate.

Because her heart problems didn't go away, in early 2022 her doctors began conducting a series of lab tests in an attempt to better understand her long Covid symptoms.

When Maness submitted the testing to her insurance — Anthem Blue Cross — the provider deemed the testing medically unnecessary and declined to cover the cost. She’s now on the hook for the medical bills, which have already cost her more than $10,000 out of pocket.

“I’m kind of at the point sadly where I’ve just given up,” said Maness, a Ph.D. student in Sacramento, California. Many of her insurance appeals have been denied. “I don’t have the mental bandwidth to even battle this anymore, because it’s become clear that it is most likely going to be unsuccessful.”

Maness is among several long Covid patients in the United States interviewed by NBC News who say their insurance providers are declining to provide coverage related to their illness.

But there are likely many more. Up to 4 million full-time workers are out of the labor force due to long Covid, according to research from the Brookings Institution, a Washington-based think tank.

NBC News has asked insurance providers for comment.

For some, the care they need to manage their chronic illness has left them in medical debt, which can easily balloon into the thousands or even tens of thousands of dollars, experts say. It's unclear how many are being denied coverage, but a paper published in May in JAMA Health Forum estimated that the individual medical costs of long Covid could come to roughly $9,000 a year.

Part of the problem, experts say, is the ambiguity of long Covid symptoms, which can range from extreme fatigue to loss of taste and smell to debilitating heart palpitations. There's no official test to diagnose the condition, nor is there any specific recommended treatment. That makes it more difficult for doctors to come up with a proper treatment.

Before they pay, insurance companies often want to know if the treatment is proven to work.

Long Covid patients can fight the denied claims through appeals or going to court — a time-consuming and draining approach for any patient, let alone those who may suffer from fatigue and brain fog, said Michele Johnson, the executive director of the Tennessee Justice Center, a legal aid group that has helped long Covid patients get health coverage.

“They’re trying to keep their job or keep caring for their family," she said, "and there’s so much bureaucracy and red tape that they’re just drowning in it."

'Medical necessity'

Experts say insurance companies will often deny claims for care related to long Covid because they don't see it as a “medical necessity.”

The term is what insurance companies use to assess whether they should approve or deny a claim, said Linda Bergthold, a former health policy researcher at Stanford University’s Center for Health Policy.

The term has been thrown around by insurance companies for decades, but it wasn’t given a formal framework until the late 1990s, which Bergthold helped develop.

In order for the care a patient receives to be deemed medically necessary by an insurance provider, there has to be substantial research or evidence that shows that it works, she said.

That's "a key issue for long Covid," she said, because the illness is so new and still poorly understood.

"Research, just like everything with Covid, is all new," she said. "Nobody really quite knows what works and nobody really understands why some people have it longer than others."

To be sure, as of 2021, there are diagnostic codes for long Covid — key tools used by doctors to characterize medical diagnoses for insurance coverage, said Dr. Alan Kwan, a cardiologist at Cedars-Sinai Medical Center in Los Angeles. Those codes, however, don't always cover the myriad health problems linked to long Covid, he said.

POTS, for example, does not have a standardized diagnostic code and has only recently been linked to Covid.

Doctors may work hard to get a patient a formal diagnosis for long Covid to help with insurance, though there isn't an official test for long Covid and the testing that is done may not be covered by insurance.

Some patients may eventually get coverage after submitting an appeal to their insurance, but usually not before shelling out hundreds of dollars, Kwan said.

Others may not be so lucky and may be forced to pay for most of their care out of pocket.

That's what happened to Amy Cook, 51, of Orange County, California.

In May, she got Covid, which caused her multiple long-term health problems including chest congestion, erratic heart rate, headaches and visual impairment.

Cook, who works a full-time job as a chief operating officer for a consulting agency, said she was bedbound for four months because of her long Covid symptoms.

Around October, her doctor recommended that she try naltrexone, a drug used for opioid addiction that has shown promise in lifting long Covid symptoms, as well as hyperbaric oxygen. Both therapies are being tested in clinical trials as potential treatments for the condition, though neither is approved by the Food and Drug Administration for the illness.

Aetna, her insurance provider, declined to cover most of the cost of the treatments.

“I’m at $28,000 to date and I have more treatments coming up,” Cook said of her out-of-pocket expenses.

Cook said she’s currently in a financial position to be able to self-fund the treatments, although she still hasn’t recovered from her illness and the expenses could easily grow.

“I don’t know when I’ll be able to stop,” she said.

In a statement, Alex Kepnes, a spokesperson for Aetna, said there is no single definition for long Covid and that coverage decisions "are based on medical necessity and evidence-based guidelines."

"We are focused and committed to providing our members with access to care and treatments for medically necessary services to help them address their conditions and improve their health," he said.

What can be done?

Johnson, of the Tennessee Justice Center, said a patient can improve their chances of insurance approving their claim by making sure they have a plan before they even enter the doctor's office.

Her guidance:

• Ask how much the care will cost.

• Ask the doctor to explain clearly on insurance paperwork exactly why the care was needed.

Working with a doctor can be "very effective," Johnson said, as they are usually trained to know what meets insurance providers' standards for coverage.

If that doesn't work, and insurance denies the patient's claim, the patient can appeal the decision, she said. Under the Affordable Care Act, all health insurance must have an external appeal process that allows a patient to challenge the provider's verdict.

“The idea that you could deny services without an opportunity for appeal is no longer true,” she said.

If still unsuccessful at this point, patients may begin to panic, Johnson said, because the outstanding bill can be taken to collections and patients can take a hit on their credit score. Providers often provide a very short time window for payment, and appeals often take months.

Maness, of California, said she's panicked at least once when her insurance provider took too long to get back to her on an appeal and ended up shelling out hundreds of dollars toward her bill.

What a patient does after that will depend on their health insurance, Johnson said.

People with Medicaid, for example, can take the claim to court if they feel the denial was unjustified. For people on private insurance, it's less clear what they can do, but one option is to contact the state's Department of Commerce and Insurance, which regulates insurance companies.

Johnson suggested patients frame their complaint saying, "You've licensed this insurance to do this in our state and they're denying essential benefits consistently."

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This article was originally published on NBCNews.com