Even if health reform survives its political hazing, how will the Affordable Care Act fare if there aren’t enough doctors to treat all the newly insured Americans? The country is already on track to be short 40,000 primary-care doctors by 2020, according to the American Academy of Family Physicians. The problem goes straight to the heart of health reform: One of the main goals of the ACA is a massive new coverage expansion, and much of the new demand will be for primary-care services. Massachusetts, for one, has already had long waiting lists for family doctors after expanding basic insurance coverage. What’s more, the rapid rise in Medicaid enrollment, the exploding cost of Medicare and the growing chorus for deficit reduction could all exacerbate the doc supply problem.

The growing urgency of the primary-doc shortage is spawning some pretty dramatic proposals. In the New York Times this weekend, two former White House officials — alums of the Bush and Obama administrations — argue that medical school be made free to encourage more people to enter primary care. The going assumption is that the shortage is due to a wage gap problem: Family physicians earn far less than their specialist counterparts, with an average income in the mid-$100,000s, as compared to upwards of $300,000 for oncologists, radiologists and the like. They also have less flexible hours, more on-call time and other downsides that have been discouraging to debt-ridden doctors-to-be. 

In their op-ed for the Times, Peter Bach and Robert Kocher suggest that either government subsidies or fees for specialty training could offset the expense. They peg the total cost at $2.5 billion — a tiny fraction of total health-care spending — arguing that the investment will go a long way in changing incentives for career paths in the medical profession.

Subsidizing medical school could arguably begin to realign incentives for doctors. But it wouldn’t address a wage gap for doctors that could grow even bigger given the problems plaguing country’s biggest entitlement programs. More Americans than ever will soon be enrolled in both Medicaid and Medicare, because of the recession, the ACA’s coverage expansion and an aging population. In light of these skyrocketing costs, there’s been a growing call to scale back these programs. Although opponents to draconian entitlement reform have focused on cuts to beneficiaries, fees to providers are also at risk — and primary-care doctors could bear the brunt of it.

In Medicaid, reimbursement fees are already so low that more doctors are refusing to see Medicaid patients. States are threatening to reduce doctors’ Medicaid fees even further as they’ve struggled to balance their budgets, and the Obama administration affirmed their right to do so last Thursday in a brief filed at the Supreme Court. Though Medicare reimbursement rates are comparatively higher, the program is continuously on life support as rising health-care costs have forced Congress to readjust its payment formula for doctors — known as the Sustainable Growth Rate — resulting in a showdown over the “doc fix” nearly ever year. Recognizing the disincentives for family doctors, the ACA does provide Medicare payments to primary-care providers that are 10 percent higher. But the tweak doesn’t remove the Sword of Damocles that is continually hanging over Medicare’s provider fees.

So even if the entire cost of medical school were removed from the equation, the cloudy future for both Medicaid and Medicare might remain another huge disincentive for entering primary care, which lies at the foundation of both entitlements. Teaching hospitals and those that serve low-income, elderly and other vulnerable populations are particularly at risk of these provider cuts, so altruistically minded doctors willing to accept lower pay might be still dissuaded from pursuing this path given the sheer uncertainty ahead.

In other words, Washington’s political battle over entitlement reform could have another casualty: If lawmakers don’t find a more consistent, sustainable way to address provider rates, they could end up further depleting the future ranks of primary-care doctors. Given how long it takes to train new doctors, it could take that much longer to close the primary-doc supply gap.

Suzy Khimm is a staff reporter in the Washington bureau of Mother Jones.