Uncompensated care is care provided by hospitals and doctors that is not covered by insurers or patients themselves, either because the patient is completely uninsured or because they cannot cover their out-of-pocket medical costs.
These costs are ultimately passed along to consumers who can afford to pay for their own health care, as well as to state and local governments, or end up being eaten as a loss by health-care providers.
"You have a big problem, because there is nothing in the law that would increase the [amount] of federal payments" that offset the costs of providing uncompensated care, said John Holahan, institute fellow at the Urban Institute's Health Policy Center, a co-author of the report.
The report, funded by the Robert Wood Johnson Foundation, noted that the $1.7 trillion estimate is based on "the amount of care the newly uninsured would seek, not the value of the uncompensated care they would actually receive."
The increase in uncompensated care would come as a consequence of lower overall health spending by insurers and households. The report estimates that there would be about $1.6 trillion less in such spending by insurers and households, according to the report.
Congress this week began laying the groundwork to repeal the ACA, as President-elect Donald Trump has planned, and which could lead to big increases in the number of uninsured people.
Since the ACA has been in effect, uncompensated care costs at hospitals have sharply fallen. The biggest drops, by far, have come in states that expanded their Medicaid eligibility standards to allow coverage of more poor adults, as allowed by Obamacare. Medicaid expansion has led to to biggest gains in coverage under the ACA.
A repeal scenario "being considered by Congress would create more uninsured people than would have been the case had the ACA never been passed," said Matthew Buettgens, senior research associate at the Health Policy Center.
"The increases in uncompensated care sought by the newly uninsured would be more than state and local governments and health providers could internalize, undoubtedly leading to substantially more unmet medical need."