For example, Eskimos, most of whom live in the non-expansion state of Alaska, had a 33 percent uninsured rate without the ACA. With the ACA, the rate is expected to be cut in half, to 16.3 percent, by 2016. But if Alaska expanded Medicaid benefits, along with other states, the uninsured rate among Eskimos would drop to 9 percent.
In two other non-expansion states, South Dakota and North Carolina, the Sioux and Lumbee tribes, respectively, would see dramatically steeper drops with Medicaid expansion than they will without it.
But Clemans-Cope said that even if all states expanded Medicaid, there would still be differences between the various ethnic groups in their uninsured rates, which have been "a long-standing issue in this country."
The projections for Latinos by the Urban Institute underscore that fact. Even with full Medicaid expansion, the uninsured rate among Latinos is projected to be more than 15 percent, leaving them in first place with that rate, and more than 10 percentage points higher than the lowest rate, which would be among whites.
A large part of that gap will be due to the fact that undocumented immigrants are not eligible for either Obamacare subsidies or Medicaid. Such immigrants account for a significant minority of the Latino population in the U.S.
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Clemans-Cope said that Latinos, compared to other ethnic groups, "express less desire for health insurance to start out with," and are more likely than whites to work for employers who don't offer health coverage as part of their compensation.
Speaking of underinsured minority groups in general, Clemans-Cope said, "You also have differences in behavior that are historical and are likely to continue in this population" that will lead to continued gaps in coverage.
"Some groups have low health literacy, and don't understand the health insurance landscape as well as others," she said.