The American Medical Association is warning U.S. Senate leaders that millions of Americans risk losing health care if "significant changes" are made to the Affordable Care Act or Medicaid.

In an open letter to Senate leaders, AMA President James Madara said the ACA could be improved, but his group does not support changes that would leave millions uncovered or weaken the nation's health care safety net.

"We believe that the ACA was a major step toward the ultimate goal of ensuring that quality, affordable health insurance is available to all Americans, regardless of their health care status or economic situation," he said.

The Senate is considering health care overhaul after the House of Representatives passed the American Health Care Act May 4. AMA and most medical groups oppose the bill, but Madara did not mention the legislation by name in his letter.

Instead, Madara pointed to the millions of Americans who gained insurance because of the subsidized coverage provided by the ACA. He also pointed to those people who gained coverage through Medicaid expansion. (ACHA would reduce funding for Medicaid.)

"Changes to the financing of Medicaid must also guarantee that the safety net remains strong and is able to respond quickly, not only to changes in enrollment but to sudden and unforeseen increases in necessary medical expenditures such as epidemics or breakthrough treatments for serious medical conditions," Madara said.

The fate of ACHA in the Senate is uncertain. Senate Republicans were not enthusiastic about the bill and have vowed to draft their own legislation. http://bit.ly/2qsur4H

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