WASHINGTON Having trouble finding a doctor?

You're not alone.

Tens of millions of adults under age 65 both those with insurance and those without saw their access to health care worsen dramatically over the past decade, according to a study abstract released Monday.

The findings suggest that more privately insured Americans are delaying treatment because of rising out-of-pocket costs, while safety-net programs for the poor and uninsured are failing to keep up with demand for care, say Urban Institute researchers who wrote the report.

Overall, the study published in the journal Health Affairs found that one in five American adults under 65 had an "unmet medical need" because of costs in 2010, compared with one in eight in 2000. They also had a harder time accessing dental care, according to the analysis based on data from annual federal surveys of adults.

"For decades, Americans have been facing costs rising well above wage levels," said Lynn Quincy, senior policy analyst for Consumers Union, a nonpartisan group. "These are real families. ... It's very concerning."

The 2010 health care law, which will expand health coverage to 30 million people starting in 2014, won't necessarily solve all those access problems, the study said. That's because the law, which is under review by the Supreme Court, may not alter the trend toward private insurance policies with larger deductibles and higher co-payments or address some of the barriers within public coverage. While the law does increase payments temporarily to primary care doctors who see people covered by Medicaid, it will not force more doctors into the program, or require states to provide dental coverage to adults.

Quincy noted that the law does offer several new strategies, such as new payment methods to control rising costs, which could help improve access, but there's no guarantee they will work.

The study underscores what's at stake in the law's coverage expansion: People with private or public health insurance have significantly better access to care than the uninsured. If the law is overturned or scaled back, "we would be likely to see further deterioration in access to care for all adults uninsured and insured alike," it concludes.

The percent of adults with private insurance who reported an "unmet medical need" doubled to 10 percent from 2000 to 2010, while those who delayed seeking care because of cost rose from 4 percent to 7 percent in the same period, according to the study.

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Access to health care in U.S. worsens, study finds