Bohn said the study overall presents a mixed picture.
Millions of now-uninsured people will be covered as the market for directly purchased insurance more than doubles with the help of government subsidies. The study found that market will grow to more than 25 million people. But costs will rise because spending on sicker people and other high-cost groups will overwhelm an influx of younger, healthier people into the program.
Some of the higher-cost cases will come from existing state high-risk insurance pools. Those people will now be able to get coverage in the individual insurance market, since insurance companies will no longer be able to turn them down. Other people will end up buying their own plans because their employers cancel coverage. While some of these individuals might save money for themselves, they will end up raising costs for others.
Part the reason for the wide disparities in the study is that states have different populations and insurance rules. In the relatively small number of states where insurers were already restricted from charging higher rates to older, sicker people, the cost impact is less.
"States are starting from different starting points, and they are all getting closer to one another," said Bohn.
The study also did not model the likely patchwork results from some states accepting the law's Medicaid expansion while others reject it. It presented estimates for two hypothetical scenarios in which all states either accept or reject the expansion.
Larry Levitt, an insurance expert with the nonpartisan Kaiser Family Foundation, reviewed the report and said the actuaries need to answer more questions.
"I'd generally characterize it as providing useful background information, but I don't think it's complete enough to be treated as a projection," Levitt said. The conclusion that employers with sicker workers would drop coverage is "speculative," he said.
Another caveat: The Society of Actuaries contracted Optum, a subsidiary of UnitedHealth Group, to do the number-crunching that drives the report. United also owns the nation's largest health insurance company. Bohn said the study reflects the professional conclusions of the society, not Optum or its parent company.
AP White House Correspondent Julie Pace contributed to this report.
Society of Actuaries __ http://www.soa.org/NewlyInsured/
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