Relaxing prohibitions against age means seniors and preretirees would be paying large premiums just at the age when they're likely to need medical care. Add to that the fixed and usually low incomes seniors live on, plus the deductibles, copays and other amounts they have to pay, and you have a problem.

In addition, Daily Kos reported that Georgia congressman and Trump pick for secretary of Health and Human Services Tom Price introduced a plan in 2011 that would allow balance billing for seniors on Medicare—something he'd be free to reintroduce if confirmed.

Balance billing allows physicians to require patients to pay the full balance of their fees, even if those fees are far in excess of Medicare-allowable charges.

Under Price's plan, the article said, physicians would no longer have to "exit the Medicare program entirely should they enter agreements to independently bill the patients for the balance of their fees…."

In addition, "there would be no limit on prices medical providers choose to 'negotiate' with otherwise Medicare-eligible patients under the Price plan."

Doctors could collect fees from Medicare and then collect the balance of whatever they choose to charge from the patient. Given the limited incomes on which most retirees survive, many could end up in bankruptcy or worse after just one illness or hospitalization.

Additionally, a  post on the DC Medical Malpractice and Patient Safety blog points out "how, under the Affordable Care Act, officials pressed doctors and hospitals, especially through Medicaid and Medicare, to reduce costs and to improve safety, efficiency and effectiveness in the health care system" with bundled payments for hip and knee replacements, common procedures for seniors.

Congressman Price has also signalled his opposition to bundled payments and is determined to halt the practice.

An op-ed on The Hill called block grants "a potentially greater threat to the health and wellbeing of over 80 million of Americans," adding that currently circulating proposals to change Medicaid "would result in a reduction in benefits for millions, at best, and an elimination of benefits for millions, at worst."

It cited AARP figures that 65 percent of seniors in nursing homes were covered by Medicaid—coverage they might lose under a block grant proposal that would provide states with a fixed pool of money, rather than act as a single payer, to cover all residents who qualify.

But as that pool would not expand and could, instead, shrink at the whim of politicians, that would inevitably lead to efforts by states to rewrite the rules about who qualifies, so as to reduce the number of people on whom money has to be spent.

And that's just the seniors who benefit from Medicaid.

The op-ed also pointed to a Kaiser Family Foundation study that finds Medicaid pays for 39 percent of American children's health insurance and a MedPAC report that over 9 million people with disabilities get health and home care through Medicaid.

Children who don't receive Medicaid benefits, according to the National Bureau of Economic Research, are less likely "to finish high school, attend and graduate from college and, as a result, go on to earn more as adults." Caregivers for seniors and the disabled would no longer be able to work, thereby incurring "income and benefits losses total[ing] hundreds of thousands of dollars." As earnings, or lack thereof, affect retirement savings, future retirees could also feel the impact of the two current proposals.