The spirit of the Affordable Care Act (ACA), or "Obamacare," is to achieve some semblance of universal health insurance coverage. And, by several accounts, the ACA is working. Ninety percent of US citizens now have health insurance, and the uninsured rate is at an all-time low.  A recent study found that primary health care utilization has improved across the country, in direct correlation with the law.

But, like most major policy reforms, there have been snags. Aetna and UnitedHealthcare, for example, recently announced that they were exiting some — but not all — of the Marketplace Exchanges. It was also recently announced that some premiums (i.e., what consumers pay for their health insurance coverage) would be going up by an average of 25 percent in the 36 states that have not set up their own marketplace exchanges (and are coordinated through HealthCare.Gov instead). While these events are not ideal for the ACA and may sound alarming to some taxpayers and consumers, they do not signal a failure in the implementation of the law. Most health policy experts expect that, in the long-run, the ACA will remain viable and solvent, albeit some policy tweaking will be required.

The recent news about the rise in premiums for some ACA beneficiaries highlights the need to reduce the risk of the Marketplace insurance pool. One strategy is to increase the number of younger, healthier people into the Marketplace, as this group typically does not use a lot of health care. Another potentially effective, albeit controversial, way to accomplish this would be to allow the ACA to cover the country's 11–12 million undocumented immigrants.

Many have argued that undocumented immigrants should be excluded from our health care system because they have not earned the right to access it. However, an argument for including them — beyond the moral issue of valuing health as a human right — is that undocumented immigrants tend to be younger, healthier and use much less health care than other population groups. Much like other young adults, undocumented immigrants paying premiums into the Marketplace could improve the risk of the insurance pool and potentially drive down premiums for everyone while offsetting the costs of covering older and sicker beneficiaries.

Embedded into the ACA is the philosophy of population health. That is, that health care systems and public health agencies must promote primary and secondary prevention strategies in order to improve the health of not only individuals but also communities. By doing so, health care costs will be reduced by preventing disease and illness. Excluding undocumented immigrants from ACA population health interventions puts them at risk for preventable chronic illnesses that are costly to treat over the long run. These costs are likely to be trickled down to local tax payers (especially as Disproportionate Share Hospital (DSH) payments will be reduced over time) who help cover uncompensated health care at local safety net clinics and hospitals.

Some states are starting to figure this out. California, for example, which has more than two million undocumented immigrants, recently approved legislation that would allow undocumented immigrants to participate in the Marketplace Exchanges but without subsidies (the state is still waiting for a 1332 waiver from the Feds). The state will also be allowing undocumented children to benefit from its Medicaid program (called Medi-Cal). California and 14 other states (including DC) already allow legally authorized immigrants who have been in the country for less than five years to participate in Medicaid; these immigrants are barred from participating in Medicaid in other states as part of 1996 Welfare Reform Law. The premium for California's benchmark exchange is only increasing by 7 percent, unlike the average of 25 percent in the (mostly red) states that are not coordinating their exchanges.

As the saying goes, as goes California, so goes the nation. As policymakers consider ways to make the ACA more sustainable, they must consider Marketplace strategies that would increase purchasers while decreasing the risk of the insurance pool in order to reduce premiums and costs. Taking that into account, even if we don't let our moral compass play into the decision, it just makes economic sense to include the undocumented in the ACA.

Alex Ortega is Professor and Chair of the Department of Health Management and Policy and Director of the Center for Population Health and Community Impact in the Dornsife School of Public Health at Drexel University.

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