About 9 million adults became uninsured over the past two years, and even many with jobs saw an erosion of benefits that plunged more into medical debt and caused them to delay care, according to a new report.

During the economic crisis, only a quarter of people who lost employer-sponsored health benefits found another source of coverage, according to the report by the Commonwealth Fund. An estimated 52 million Americans were uninsured sometime in 2010, according to the telephone survey of about 4,000 adults nationwide.

Despite a government subsidy, just 14% of the newly jobless continued their employer-based coverage through COBRA. Many were shut out of other coverage options, either because of prohibitive costs or a pre-existing medical condition. Of adults who tried to buy individual policies over the past three years—19 million people—71% could not get such coverage for these reasons.

The result is that people are forgoing care and paying steep medical bills, the report found. Only half of adults under age 64 are up to date with preventive care, for instance. Forty-nine million working-age adults spent 10% or more of their income on out-of-pocket costs and premiums, up from 31 million in 2001. A full 73 million Americans had problems paying medical bills, up from 58 million in 2005, the report found.

The healthcare reform law—with insurance subsidies, rules on coverage denials and standard benefit packages—could improve the situation, said Sara Collins, vice president of the Commonwealth Fund. “These reforms have enormous potential to begin solving the problems identified in this report,” Collins said.