Sen. Susan Collins, R-Maine, warned Monday that Congress will likely face "tremendous pressure" to change portions of President Donald Trump’s sprawling legislative package after the bill’s deep Medicaid cuts begin to take effect.

Speaking at the Global Health Innovation Forum at Massachusetts General Hospital in Boston, Collins said she supports several major elements of the measure, including extensions of provisions from the 2017 Tax Cuts and Jobs Act and efforts to strengthen Medicaid work requirements, but that the nearly $1 trillion in Medicaid reductions included in the bill risk harming vulnerable patients and straining health systems.

"They don't go into effect next year, they go into effect the following year," Collins said. "But a year is not going to make any difference at all, and I'm just very concerned that people who need the care aren't going to get it." She said that if Americans begin to get sicker because they delayed treatment after losing coverage, lawmakers will be obliged to reassess the cuts they approved in June.

Collins was one of three Senate Republicans who voted against the package when it passed the Senate in a marathon 29-hour vote-a-rama in June; Sens. Rand Paul of Kentucky and Thom Tillis of North Carolina joined her in opposition. At the time, Collins said the Medicaid reductions were the principal reason for her "no" vote, and she told GOP leaders and White House officials beforehand she would not support the bill without changes.

She said she provided Republican leaders and the administration with a list of 10 items of concern, including cuts she said would threaten rural hospitals. Collins noted that Maine has about 32 rural hospitals, one recently closed and five that she described as "teetering on the brink of closure." She warned that lower Medicaid reimbursements and demographic shifts make it unlikely that states could fill the funding gaps.

Lawmakers secured a $50 billion fund within the measure aimed at supporting rural hospitals, a concession Collins and other skeptics pressed for during negotiations. Collins said she would press Centers for Medicare and Medicaid Services Director Mehmet Oz to move quickly to distribute that assistance.

Big, Beautiful Bill graphic

Collins said she expects pressure to grow as the real-world effects of the cuts become clearer. "I don't see the states having the ability to step up and fill the gap here. I just don't. Even wealthy states," she said. "And as the implications of the bill become better known, I think there's going to be tremendous pressure on Congress to change the law. But we're going to need the evidence, the stories, the research that didn't occur."

She warned hospitals could face rising uncompensated care as patients who lose Medicaid coverage seek treatment in emergency departments. "They're going to be coming to you with their problems, and they're not going to be covered by Medicaid, and the problem with that is it's going to be uncompensated care for hospitals," Collins said.

The bill’s Medicaid reductions are scheduled to take effect in the year after next, a timeline Collins said will not blunt their impact. She urged collection of evidence and patient stories to document the effects and inform any future legislative fixes.

White House officials did not immediately respond to a request for comment. Analysts and health policy experts have previously said that while targeted funding and transitional supports can mitigate some impacts, large federal funding cuts to Medicaid typically shift costs to states, providers and patients.

President Donald Trump in the Oval Office

Collins’s comments underscore fractures within the GOP over the scope and pace of spending reductions embedded in the administration's signature legislative effort. With Medicaid covering large shares of the populations of some states, senators from those states have signaled they will closely watch enrollment, access and hospital finances as the law’s provisions begin to apply. Lawmakers on both sides of the aisle have in recent years moved to collect data and anecdotal evidence after major changes in federal health policy in order to inform potential corrections or new legislation.

As the effects of the legislation emerge, Collins said Congress will need rigorous research and concrete examples to guide any changes, and that she expects constituent experiences and state fiscal data to drive the debate.