Newly enrolled Obamacare customers have higher rates of disease than individuals who had coverage prior to healthcare reform, according to a new report from a major insurer.

The Blue Cross and Blue Shield Association released the report Wednesday, looking at the impact of healthcare reform on enrollees in 2014 and 2015.

The report compared people who had individual coverage through 36 independent Blue Cross Blue Shield insurers both before and after the introduction of Obamacare in 2014. The individual insurance market is for those who don't have employer-based coverage, and it's now dominated by Obamacare enrollees.

It found that members newly enrolled in Blue Cross plans in 2014 and 2015 "have higher rates of certain diseases such as hypertension, diabetes, depression, coronary artery disease, HIV and hepatitis C than individuals who had [Blue Cross] individual coverage prior to healthcare reform," the assocation said.

The report found that new enrollees had HIV and hepatitis C rates of 41 and 24 per 10,000 people, respectively, compared with 12 and 10 before Obamacare went into effect.

The report also looked at the cost of the new enrollees, saying that they cost on average 19 percent more than people in employer-based group plans in 2014 and 22 percent higher in 2015.

The report comes as insurers are struggling to gain profitability on the exchanges. America's largest insurer, UnitedHealthcare, has previously said it may leave the exchanges due to $400 million in losses.

Insurance giant Anthem, which bought Blue Cross Blue Shield, has said that its business on the exchanges hasn't been profitable, but is willing to stick it out in case the Obamacare market stabilizes.

Enrollment in Obamacare has been lower than expected. The nonpartisan Congressional Budget Office initially expected that 21 million people would sign up for Obamacare for 2016 coverage, but that figure was downgraded to 13 million people.

Obamacare signed up 12.7 million people during the latest open enrollment that ended in January, and the administration has a goal of 10 million people paying for coverage by the end of the year.

The administration punched back on Wednesday against the Blue Cross report by noting that the spikes in sicker enrollees can be attributed to the Obamacare provision that requires insurers to take people with pre-existing conditions.

"After years of being discriminated against, Americans with pre-existing conditions are no longer locked out of coverage because of a health condition like asthma or diabetes," said Ben Wakana, spokesman for the Department of Health and Human Services. "It's no surprise that people who newly gained access to coverage under the Affordable Care Act needed healthcare; that's why they were locked out of coverage before."