Nearly two-thirds of U.S. doctors surveyed fear healthcare reform could worsen care for patients, by flooding their offices and hurting income, according to a Thomson Reuters survey released Tuesday.

The survey of more than 2,900 doctors found many predict the legislation will force them to work harder for less money.

"When asked about the quality of healthcare in the U.S. over the next five years, 65 percent of the doctors believed it would deteriorate with only 18 percent predicting it would improve," Thomson Reuters, parent company of Reuters, said in a statement.

The U.S. House of Representatives began debate Tuesday on efforts to repeal President Barack Obama's overhaul of the U.S. healthcare industry.

Repeal of the bill is likely to fail in the Senate.

Also Tuesday, the Health and Human Services Department released a study predicting that up to 129 million Americans under 65 who have a pre-existing health condition would risk losing health insurance or be denied coverage if the bill is repealed.

Polls show consumers are divided about the impacts of healthcare reform and the House debate has presented an opportunity for many groups to make their arguments for or against it.

Reimbursement Concern

Thomson Reuters researchers and physician services company HCPlexus surveyed 2,958 doctors of varying specialties from 50 states plus Washington, D.C. via fax.

The survey found that 65 percent of the doctors predict healthcare quality will decline over the next five years, 18 percent say it will improve and 17 percent believe it will remain the same.

Most — 74 percent — believe the changes will make their reimbursement less fair, according to the survey, available here.

HHS has predicted that 32 million Americans who do not currently have health insurance will receive it under healthcare reforms.

When asked where most of these newly insured people would get care, 55 percent of the doctors said a nurse practitioner or physician assistant would provide care.

As for patients, 57 percent of doctors predicted the impact of the changes will be negative, 27 percent said they would be positive and 15 percent forecast a neutral effect.

"The National Physicians Survey tells us that physicians have not been enlisted in the healthcare reform process," said David Shrier, chief executive officer of HCPlexus.

"The message they've taken from healthcare reform appears to be 'Do more with less.' Doctors are telling us they feel disenfranchised and overburdened," Shrier added in a statement.

Doctors were also asked about electronic medical records, a major initiative of HHS and of healthcare reform.

There, opinions were split, with 39 percent saying electronic medical records would help patients, 37 percent saying the effect would be neutral and 24 percent saying they would hurt care.

"Our present survey suggests that greater attention should be paid to understanding the present opinions of the health care provider constituency before proceeding down a path of reform.

Without the physicians supporting change it will be difficult to accomplish," the report concludes.