About 18% of moderately high-income families that live in high-cost areas and have big medical bills could still have trouble paying for health coverage even if the Affordable Care Act takes effect as written and works as supporters hope, researchers say.

Jonathan Gruber and Ian Perry, researchers at the Massachusetts Institute of Technology, have published an analysis of the affects of Affordable Care Act coverage ownership requirements on consumers in a paper distributed by the Commonwealth Fund, New York.

The Affordable Care Act – the legislative package that includes the Patient Protection PPACA toolkitand Affordable Care Act of 2010 (PPACA) – is supposed to start requiring many individuals and families with incomes over a minimum level to own health coverage or pay penalties.

The PPACA minimum coverage requirement would exempt people with religious objections health coverage and taxpayers who would have to spend more than 8% of their income on out-of-pocket health care costs and payments for basic, “bronze plan” health insurance premiums.

About 90% of U.S. families over the federal poverty level probably would be able to afford coverage, in part because the government would provide free coverage for low-income people and subsidies for moderate-income taxpayers with incomes under 400% of the federal poverty level, the researchers say.

But even families with incomes equal to 400% or 500% of the federal poverty level have

relatively modest income levels by the standards of many financial professionals, and especially by the standards of financial professionals who live in expensive communities such as New York and Boston.

A family of 4 would have to earn just $112,000 per year to have an income over 500% of the federal poverty level.

The researchers prepared a chart that shows “no room for health insurance premiums” levels for families with expenditures on necessities such as food and housing in the top 10% for their income level and out-of-pocket health care costs in the top 10%.

At those living expense and health care expense levels, about 18% of the families with incomes equal to 400% to 450% of the federal poverty level might have trouble paying for health coverage, and even 3.2% of the families with incomes greater than 400% of the federal poverty level might have trouble paying for coverage, the researchers say.

Conditions for those families might be somewhat better for those families than they are today, forever, because the families would be able to buy coverage on a guaranteed-issue, mostly community-rated basis.

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