Press Release

Embargoed Until Contact

October 26 , 2011
4:00 p.m. EST

Sue Ducat
Director of Communications
(301) 841-9962


From Health Affairs

The Impact Of The Affordable Care Act On Coverage And Medicaid Enrollment


Bethesda, MD -- Two new studies, released online today as Web First articles by Health Affairs, examine some of the ramifications of the Affordable Care Act. One, by Benjamin Sommers, Katherine Swartz, and Arnold Epstein, all of the Harvard School of Public Health, created a simulation model that predicted the number of new Medicaid enrollees by 2019 could vary anywhere from 8.5 million to 22.4 million Americans, suggesting that policy makers need to prepare for a broad range of contingencies. The second, by John Sheils and Randall Haught, of the Lewin Group, estimated that if the individual mandate were eliminated, the Affordable Care Act would still cover some 23 million previously uninsured US residents, indicating that the absence of the mandate might not preclude the act's successful implementation. Both studies will also appear in the November issue of Health Affairs.

Policy Makers Should Prepare For Major Uncertainties In Medicaid Enrollment, Costs, And Needs For Physicians Under Health Reform
By Benjamin Sommers, Katherine Swartz, and Arnold Epstein
Sommers, Swartz, and Epstein are affiliated with the Harvard School of Public Health; Sommers is also an assistant professor of medicine at Harvard Medical School and Brigham and Women's Hospital, all in Boston.

Research for this study was partially supported by funding from the Agency for Healthcare Research and Quality.

The number of new individuals enrolling in Medicaid by 2019 has been projected by the Congressional Budget Office (CBO) to be sixteen million and by the Centers for Medicare and Medicaid Services (CMS) to be eighteen million. But details on how these agencies make these predictions--and how precise they are--is not known. Knowing how many people will actually enroll in Medicaid is important for health care access, budget planning, and ensuring an adequate provider workforce to care for newly insured patients. To explore how many people would become newly eligible and would ultimately enroll--and how widely the possible estimates might vary--the authors used data from the 2009 Current Population Survey and the 2008 Survey of Income and Program Participation, both conducted by the Census Bureau. In addition to arriving at a base-case estimate of 13.4 million new Medicaid enrollees, the authors found that using alternative reasonable assumptions leads to widely varying estimates, from 8.5 million to 22.4 million enrollees. In addition, the results indicate that 4,500 to 12,100 additional physicians would be needed to care for the new Medicaid patients. Although the Affordable Care Act offers enhanced Medicaid reimbursements to primary care physicians in 2013-14, the trend among some physicians to turn away Medicaid patients may pose challenges in health care access for these new patients. "In the end, Medicaid enrollment will be determined largely by the extent to which federal and state efforts encourage or discourage eligible people from enrolling," conclude the authors. "The results of these efforts will have major implications for health care access, Medicaid budgeting, and provider workforce needs for decades to come."


Without The Individual Mandate, The Affordable Care Act Would Still Cover 23 Million; Premiums Would Rise Less Than Predicted
By John F. Sheils and Randall Haught

Sheils and Haught are with The Lewin Group, a health care policy research and management consulting firm in Falls Church, Virginia.


The constitutionality of the individual mandate in the 2010 Affordable Care Act, requiring most Americans to have health insurance by 2014, is expected to be taken up soon by the US Supreme Court. This study attempts to discern whether the potential loss of the individual mandate would lead to a "premium spiral," in which healthy people would drop coverage, the cost of premiums would increase, and the number of uninsured would rise. The authors used the Health Benefits Simulation Model, based on data from the Agency for Healthcare Research and Quality's Medical Expenditure Panel Survey of households; the Kaiser Family Foundation's annual survey of employer health plans; and other recent health spending and coverage data from various federal sources. They simulated the impact of the Affordable Care Act on coverage and premiums with and without the mandate, assuming that all other features of the act--including the Medicaid expansion, premium subsidies, employer tax credits, and employer penalty provisions-- were unchanged. Without the individual mandate, the authors estimated the total number of uninsured people would increase by about 7.8 million--2.1 million fewer with employer coverage, 1.2 million fewer with Medicaid, and 4.5 million fewer with nongroup coverage. Estimates from the Congressional Budget Office and the Center for American Progress are significantly higher; the authors say those are due to differences in methods and assumptions. Also, they point out, many of those with individual coverage would be protected from some or all of the premium increases by an automatic increase in premium subsidies, which was less of a factor in the other estimates. "Our study suggests that although the mandate has important effects on premiums and coverage, it might not be essential to the act's successful implementation," they conclude.

About Health Affairs

Health Affairs is the leading journal at the intersection of health, health care, and policy. Published by Project HOPE, the peer-reviewed journal appears each month in print, with additional Web First papers published periodically and health policy briefs published twice monthly at You can also find the journal on Facebook and Twitter. Read daily perspectives on Health Affairs Blog. Download weekly Narrative Matters podcasts on iTunes.

The full text of each Health Affairs Web First paper is available free of charge to all Web-site visitors for a two-week period following posting, after which it switches to pay-per-view for nonsubscribers. Web First papers are supported in part by a grant from The Commonwealth Fund.