The Affordable Care Act helped insurers increase individual major medical enrollment to 10.9 million in 2014, from 7.9 million in 2010.
But about 2.3 million of the 3 million additional enrollees covered in 2014 had either a major health problem, such as cancer, or a serious but less severe health problem, such as high blood pressure or depression.
About 1.4 million of the additional 2014 enrollees had a severe health problem, such as cancer or heart disease, that would probably have kept them from getting ordinary major medical coverage in states that allowed medical underwriting in the individual market before Jan. 1, 2014.
Officials at a policy office at the U.S. Department of Health and Human Services gave those figures in a commentary designed to show how the ACA has helped people with pre-existing conditions.
HHS based the commentary on data from the 2014 Medical Expenditure Panel Survey, a government survey that collects coverage information and detailed health status information at the same time.
The ACA banned use of personal health information other than age, location and tobacco use in individual major medical underwriting starting in January 2014.
HHS officials estimate that about 51 percent of all Americans under age 65 have some kind of condition, such as mild asthma, that could have made getting through the major medical application process difficult in 2013, and that 23 percent have a serious health problem that probably would have made getting medically underwritten coverage impossible.