PhotoThanks to the new health care law passed last year, millions of people now without health insurance will be required to get it. But some health researchers say that doesn't necessarily mean more people will get better health care.

Since 2005, U.S. doctors have been accepting fewer and fewer patients with health insurance, according to the research team, which reports its findings in the June 27th issue of Archives of Internal Medicine.

As a result, says Dr. Tara Bishop, assistant professor of public health at Weill Cornell Medical College, and lead author of the study, insured patients could face new obstacles to receiving the medical attention they need, and overall access to health care could actually contract.

Bishop, who is also a practicing physician at New York-Presbyterian Hospital/Weill Cornell Medical Center, and her fellow investigators looked at survey data from a national survey run by the CDC's National Center for Health Statistics and found an overall decline in physician acceptance of several types of insurance.

First, they noted a modest drop in acceptance of Medicare patients, from 95.5 percent in 2005 to 92.9 percent in 2008. Doctors also turned more and more Medicaid patients away over the four-year period -- a phenomenon the authors attribute to Medicaid's historically low reimbursement rates.

Privately-insured patients fall from favor

But the most surprising decline of all was seen in doctors' acceptance of new patients with private insurance.

"Given the medical profession's widely reported dissatisfaction with Medicare, we expected to find hard evidence that Medicare patients were being turned away," Bishop said. "Instead, we saw only a modest decline in doctors' acceptance of patients on Medicare. The survey data showed a more significant decline in their acceptance of patients with private insurance."

Physician acceptance of patients with traditional fee-for-service private insurance declined from 93.3 percent in 2005 to 87.8 percent in 2008.

What's behind the change?

This change could be traceable to two major factors, she explains: inadequate reimbursement levels that have not kept pace with medical practice expenditures; and the tangle of administrative issues that go hand in hand with private health insurance.

"At a moment when the country is poised to achieve near-universal coverage, patients' access to care could be a casualty of the collision between the medical profession and the insurance industry," said Bishop.

The researchers say they hope their study will alert policymakers to potential problems in health care access, exacerbated by current shortages in primary care, an aging population, the growing prevalence of serious chronic diseases, and the imminent expansion of health insurance coverage as mandated under health care reform.

"Consumers and health advocacy groups, too, should be aware of these early warning signs so that they can work to ensure access to quality medical care," Bishop said.