Medicare was created in 1965 when people over 65 found it virtually impossible to get private health insurance coverage. Medicare made access to health care a universal right for Americans 65 and over. It improved the health and longevity of older Americans, as well as their financial security. Initially, Medicare consisted solely of a public insurance program that included all seniors.
Today, a mixed public-private health insurance market exists under Medicare. An examination of it is very instructive in terms of how a mixed public-private system would be likely to work if extended to people under age 65. The Medicare-eligible population has been able to enroll in private health insurance plans since the 1980s. The private health insurance industry lobbied heavily for access to the large, Medicare market.
Private health insurers argued for a private option under Medicare, stating that they could deliver better quality services at lower cost due to their efficiencies, thereby saving Medicare money. Initially they were paid 95% of what a Medicare enrollee cost based on promised efficiencies. However, once they had their foot in the door, the private insurers successfully lobbied for their payment rate to be increased. In 2009, it was as high as 120% of what a senior enrolled in the traditional, public Medicare program cost.
Not only have private health insurers been getting paid more per enrollee than it costs the government to serve seniors in the traditional, public Medicare insurance pool, but they have healthier enrollees who cost less to serve! Clearly, these private Medicare plans, referred to as Medicare Advantage plans, have not been saving Medicare any money, but rather costing it more than it would have to serve these seniors directly.   And there’s no evidence that they are providing better quality services that would justify such a high rate of reimbursement. The Affordable Care Act is now working to lower this over-payment to private insurers.
Since shortly after they began, the private Medicare Advantage plans have been getting over paid, and this is exactly what is likely to happen if private insurers are allowed to participate in a universal health insurance program for people other than seniors.
There are four main strategies the Medicare Advantage plans have used to get paid more than they should. Private insurers in a mixed market for non-seniors would be expected to do the same things: 
- Cherry-picking: The private Medicare Advantage insurers have worked to enroll healthier seniors who are less expensive to serve. Through targeted advertising, special benefits (e.g., subsidized health club memberships), and specialized outreach they have successfully attracted a healthier than average clientele. In the market for non-seniors, the private insurers can be expected to successfully work to attract younger, healthier, and therefore less expensive enrollees, leaving sicker and more expensive people for the public plan.
- Lemon-dropping: The Medicare Advantage insurers have implemented strategies to get sick and expensive enrollees to drop out of their plans, even though this is ostensibly illegal under Medicare. For example, they limit access to providers of expensive specialty services, require high co-pays for expensive drugs, and put a complex approval process and other barriers in front of patients trying to access expensive care. The data from Medicare Advantage plans are clear, when patients need expensive services like dialysis or nursing home care they switch back to the public, traditional Medicare in large numbers because the private insurers make it difficult to access these services and get them paid for. In the market for non-seniors, the private insurers can be expected to drop or force out the sicker, more expensive patients, dumping this burden onto the public plan.
- Over-reporting the seriousness of diagnoses: Medicare Advantage insurers report more and more serious diagnoses than they should. This makes their enrollees appear to be sicker than they are and therefore eligible for more or higher reimbursements from Medicare. For example, knee pain can be reported as arthritis and an episode of distress can be reported as major depression. Medicare’s occasional audits of Medicare Advantage insurers indicate that they are getting paid $10 billion annually for fabricated diagnoses and much more for what appear to be overly serious diagnoses. Private insurers in a non-seniors’ market can be expected to game the payment system this way too.
- Lobbying Congress for generous payments: Over the 35 years of Medicare Advantage plans, the private insurers have cost Medicare more than it would have cost for Medicare to serve their enrollees directly because Congress has directed Medicare to pay the insurers higher premiums than are warranted. These higher premiums support Medicare Advantage plans’ 14% overhead (e.g., profits, advertising, and executive salaries), which is seven times more than Medicare’s overhead of only 2%. The over-payment of Medicare Advantage plans peaked in 2009 at around 120% of the per patient costs of traditional, public Medicare. Since then, the over-payments have been reduced by provisions of the Affordable Care Act (aka Obama Care). The private health care industry has lots of lobbying clout with Congress and can be expected to strongly and successfully lobby for favorable treatment under any expansion of health care coverage to non-seniors, as they did when the Affordable Care Act was being passed. At that time, for example, they were able to eliminate a public option plan from being offered because they were scared (perhaps even knew) that a public option like Medicare for All might well out-perform them.
As the debate about changing the U.S. health care system to a universal single-payer system, e.g., Medicare for All, has been unfolding, some opponents of a single-payer system have proposed a mixed system with both private health insurers and a public health insurance option, often referred to simply as a “public option.”
Unfortunately, a mixed public-private health insurance market for non-seniors won’t achieve the efficiencies and quality of a single-payer system as is evident in the Medicare Advantage experience. A single-payer system is the only way to both improve quality and control costs. (See this previous post for more details.)
I urge you to contact your U.S. Representative and Senators, as well as candidates in the 2020 election, and ask them where they stand on moving toward a single-payer health insurance system, e.g., Medicare for All. The health care and related industries will lobby strenuously against this, but in the end a single-payer health care system will provide better health care and health outcomes for Americans and will save us all a lot of money.
You can find contact information for your US Representative at http://www.house.gov/representatives/find/ and for your US Senators at http://www.senate.gov/general/contact_information/senators_cfm.cfm.
 Patel, Y.M., & Guterman, S., 12/8/17, “The evolution of private plans in Medicare,” The Commonwealth Fund (https://www.commonwealthfund.org/publications/issue-briefs/2017/dec/evolution-private-plans-medicare)
 McGuire, T.G., Newhouse, J.P., & Sinaiko, A.D., 2011, “An economic history of Medicare Part C,” The Milbank Quarterly (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3117270/pdf/milq0089-0289.pdf)
 Himmelstein, D.U., & Woolhandler, S., 10/7/19, “The ‘public option’ is a poison pill,” The Nation (https://www.thenation.com/article/insurance-health-care-medicare/