The Trump administration is planning to fundamentally alter Medicaid, a move that could mean big changes to everything from health care to home and community-based services waivers for people with developmental disabilities.

President Donald Trump and his top advisors have indicated that they support moving to a block grant system for Medicaid. Though details are scant, such a shift may mean significantly less funding for Medicaid and greater control at the state level.

Currently, Medicaid programs are administered by the states, but they must meet certain federal requirements. In exchange, states receive matching grants from Uncle Sam, with no set cap.

Under a block grant system, however, states would likely get a finite amount of federal dollars for their Medicaid programs and more autonomy to set rules affecting everything from eligibility to coverage.

The prospect of such a dramatic shift has disability advocates bracing.

“We are very, very concerned,” said Marty Ford, senior executive officer for public policy at The Arc.

Individuals with developmental disabilities depend on Medicaid for everything from medical services to critical supports to help them live in the community.

Ford said that shifting to block grants could lead to eligibility changes, coverage cutbacks and longer waiting lists for Medicaid home and community-based services waivers, among other consequences.

“The reality is, this would be done to cut federal funding,” she said. “States generally do not have the ability to run a deficit under their constitutions so that puts more pressure on making cuts to the program.”

Republicans have yet to release any details about how exactly a block grant system might work. But Kellyanne Conway, Trump’s counselor, recently confirmed in an interview with NBC’s “Sunday Today” that block grants will be a key piece of the president’s effort to replace the Affordable Care Act.

Moving to a block grant approach would ensure that “those who are closest to the people in need will be administering it,” Conway said, adding that this change would “cut out the fraud, waste and abuse.”

Talk in Washington of such sweeping change to Medicaid is leaving providers of home and community-based services across the nation nervous, according to Gabrielle Sedor, chief operations officer at the American Network of Community Options and Resources, which represents more than 1,000 organizations providing services to people with disabilities.

“We’re hearing a lot of apprehension because (providers) don’t know what to expect and they don’t know what the administration intends,” Sedor said. “With intellectual and developmental disability services, it’s almost completely funded by Medicaid, so when you talk about changes, the impact is very direct.”

The prospect of drastically altering Medicaid comes as the program is strained, with waiting lists in most states for waivers and providers struggling with high staff turnover. A block grant approach would likely exacerbate those issues, advocates say.

“The bottom line is that Medicaid is already way underfunded,” said Julia Bascom, executive director of the Autistic Self Advocacy Network. “You see this already in states that have waiting lists and low wages for direct support professionals and the fact is that this is just going to get worse with block grants.”

Advocates said that they’re actively talking to lawmakers on Capitol Hill about the importance of Medicaid to people with developmental disabilities and they’re encouraging stakeholders to do the same. Such conversations are vital since some lawmakers don’t realize how Medicaid serves people with disabilities, instead thinking of it merely as a “poverty program,” Bascom said.