Obamacare is expected to have a dramatic effect on decreasing the number of people in each major racial and ethnic group who lack insurance in the next several years.
But the health-care reform law could have an even greater impact on driving down those numbers — particularly among blacks — if all states embraced Obamacare's expansion of Medicaid benefits, according to a new study released Tuesday.
That Urban Institute report is the first state-by-state look at how Obamacare is projected to decrease the uninsured rate by double-digits across different racial and ethnic groups: whites, Latinos, blacks, Asians/Pacific Islanders and American Indian/Alaska Natives.
Before the Affordable Care Act, there were "huge, huge differences in the uninsured rates" between various ethnic groups, noted Lisa Clemans-Cope, one of the authors of the report.
Clemans-Cope said the study found those gaps "are going to significantly narrow" with the ACA in its current state, and could shrink even further with full Medicaid expansion.
The report found that nationally, the uninsured rate may drop between nearly 52 percent among whites and 39.2 percent among Latinos by 2016. The remaining ethnic groups will see drops in their uninsured rates between those amounts, the Urban Institute said.
Those decreases represent more than 22.5 million people who would have new health coverage.
That coverage would come overwhelmingly in the form of either private, individual insurance plans sold through government-run Obamacare exchanges such as HealthCare.gov, or through enrollment in Medicaid, the joint federal-state program that covers the poor.
In terms of sheer numbers, whites — who had the lowest estimated uninsured rate without the ACA, at 13.1 percent — would be the biggest winners, with 11.1 million people gaining coverage. But behind them would be Latinos, who had the highest uninsured rate in the nation, at 39.2 percent without the ACA, and who would gain coverage for 6.6 million people.
These projections are based on the current state of ACA implementation, by which Obamacare exchanges sell health plans across the nation. However, only 27 states and the District of Columbia so far have expanded Medicaid eligibility to include nearly all poor adults as of this coming January. The remaining states have tougher Medicaid restrictions that exclude millions of poor adults, although several of them are actively considering expanding eligibility.
The Urban Institute report noted that "with full Medicaid expansion, uninsured rates are projected to fall further for all racial/ethnic groups."
Without full expansion, the uninsured rate among blacks is projected to drop from around 19.6 percent down to 11.3 percent, the report said. That drop represents nearly 3 million newly covered blacks.
But if Medicaid were expanded to all states, then the uninsured rate of blacks would plummet further, to 7.2 percent, according to the report.
"This is because over half of all blacks are living in states not expanding Medicaid in 2014," the Urban Institute said.
There are an estimated 1.4 million adult blacks who lack insurance who live in non-expansion states and who will not qualify for either Medicaid or for federal subsidies to buy Obamacare health plans.
Under the ACA, only people who earn between 100 percent and 400 percent of the poverty level qualify for financial aid to help pay premiums for private insurance purchased through an Obamacare exchange. However, people who earn less than 100 percent of the poverty level are ineligible for such federal subsidies.
The ACA, as originally written, was supposed to provide coverage to nearly all adults who earned less than 138 percent through expanded Medicaid benefits. But the 2012 decision by the Supreme Court that upheld much of the ACA also ruled that the federal government could not compel individual states to expand Medicaid.
Other than blacks, four native groups or tribes — Eskimo, Cherokee, Sioux and Lumbee — "are also projected to experience dramatic gains under the ACA with full Medicaid expansion," because of where members of those tribes live, the Urban Institute report said.
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.