Overdose

When we look back on the health-care plans of the 2008 campaign, we may wonder that no one chose to face up to one of the most troubling recent developments in American medicine. Yes, various presidential hopefuls have put forth plans containing detailed provisions to cover the uninsured, bring down costs, and improve the astonishingly uneven quality of health care. But no candidate has discussed the most dramatic change now under way in our medical system, a change that may negate many of the benefits of the plans on offer: the flood of new doctors coming down the pipeline.

Over the next eight years, medical schools are aiming to boost enrollment by as much as 30 percent above 2002 levels. More than a dozen new medical schools are being built or considered, and many of the nation’s 125 existing schools are planning to expand -- increasing the number of doctors minted each year from 16,000 to nearly 21,000. This expansion represents a stunning policy reversal by the Association of American Medical Colleges and the Council on Graduate Medical Education, which advises the federal government on how many residency positions to fund. Over the past 15 years, both organizations have raised concerns about the number of medical-school graduates, in the belief that having trained too many doctors in the 1970s and ’80s, we would see a glut of physicians. Now the AAMC is warning that we’ll be at least 100,000 doctors short by 2025 unless we hurry up and train more.

Behind the change of heart lies a cadre of economists and physicians who argue that demographic changes will make doctors scarce. First and foremost, they say, the population is expanding and the Baby Boomers are aging, resulting in more people to care for -- especially more old and sick people. Doctors are aging too, and many are retiring. Add to that a decline in the number of hours physicians are willing to put in each day and a few incipient signs of a shortage (notably longer waiting times for appointments and rising salaries for young doctors), and the conclusion that we should expand the physician workforce seems like a no-brainer.

And it would be, if not for all the complications. Those incipient signs, many experts note, may suggest something other than a shortage, and the projections for the number of doctors we’ll need aren’t all that clear-cut. Some experts would even go so far as to suggest we need fewer doctors, not more. Elliott Fisher, a physician and researcher at the Center for Evaluative Clinical Sciences at Dartmouth Medical School, quipped at a recent gathering at the Institute of Medicine, “If we sent 30 percent of the doctors in this country to Africa, we might raise the level of health on both continents.”

The physician workforce estimates rest on two critical assumptions, both of which are probably wrong.

The first is that the number of doctors practicing today is about right and that the market would send signals if supply were exceeding demand. This seems sensible enough, at least on the face of it. For most goods and services, after all, supply in any given community is limited by demand, a measure both of how much consumers need or want the product and of how able they are to pay for it. The number of car dealers in your town, for instance, depends on the number of people who want cars and can afford them.

The ability of patients to pay does help determine the number of doctors in any given community; physicians tend to congregate in places where incomes are higher and patients are more likely to be insured. (And to be sure, physicians are in short supply in parts of the country where relatively few people have health insurance, especially rural areas.) But the other component of demand -- how much health care patients want or need -- has far less influence over the supply of physicians. That’s because for the most part it’s your doctor and not you, the consumer, who determines how much care you receive. When your doctor says you need a CT scan, you get one. When your doctor says you should go to the hospital, you go. Doctors, in effect, generate some of the demand for their services, so that even when there are large numbers of them per capita, they can keep their appointment books full. There is a growing consensus among health-care analysts that this perverse feature of medical economics is spurring a great deal of unnecessary care. And there’s a corollary: New physicians won’t necessarily go to (poor, rural) places that may need doctors. Many will go to affluent areas and places featuring a high “quality of life” -- in other words, places already awash in physicians -- where they’ll generate even more demand.

The second assumption underlying the push to train more doctors is that an increase can only lead to better health, so that as long as the market can support new physicians financially, we should create more of them. This idea also rests on shaky ground. A wealth of data suggests that health care is actually no better (and if anything, worse) in parts of the country, like Manhattan and Los Angeles, where we have very high numbers of doctors and, in particular, very high numbers of specialists. In a paper published last year in the journal Health Affairs, David Goodman and his colleagues at Dartmouth’s Center for the Evaluative Clinical Sciences examined care at academic medical centers -- the hospitals that are associated with medical schools, considered the crème de la crème of American medicine. They tallied the number of doctors caring for Medicare recipients who were suffering from one or more chronic diseases and were in their last six months of life. The variation was enormous.

Medical centers at the high end, like UCLA and New York University Hospital, employed on average two to three times as many doctors per patient as did hospitals at the low end. But these high-end hospitals did not produce better outcomes than hospitals using relatively few doctors, like the Mayo Clinic, Duke, and Stanford. Other studies show that these latter hospitals consistently deliver higher-quality care -- and not just to dying patients -- using fewer physicians. And the cost of care is much lower.

Why would more doctors lead to worse care, and fewer doctors to better care? More tests and procedures always entail more risk, and for care that’s unnecessary, the ratio of benefit to risk is zero. What’s more, where numerous doctors, particularly specialists, are routinely involved in a patient’s case, the potential for miscommunication and confusion multiplies. Modern medicine should be a team sport, but it is often practiced as if everybody is running a different play. Different doctors order duplicative tests, prescribe drugs that interact poorly with what the patient is already taking, and assume another physician will attend to a critical aspect of a patient’s care. A cardiologist can be a virtuoso at slipping a stent into the coronary artery of a patient in the throes of a heart attack, but if she leaves it to another physician to prescribe aspirin to her patient -- one of the most effective treatments for preventing a second heart attack -- that prescription might fall through the cracks.

This is what appears to be happening in many hospitals, where the ratio of specialists to primary-care physicians is especially high. In one recent study, two Harvard economists -- Katherine Baicker, of the School of Public Health, and Amitabh Chandra, of the Kennedy School of Government -- examined how the quality of care in different states varied as the proportion of specialists rose. They found that measures of quality, like the percentage of heart-attack patients who received a prescription for aspirin, tended to fall in direct proportion to a rising ratio of specialists. The point, says Chandra, “is not that the specialist is inferior, but that the system is not accounting for the ‘coordination cost’ specialists are imposing.”

Medical schools are now graduating more and more specialists and fewer and fewer primary-care physicians. Between 1997 and 2005, the number of U.S. medical graduates entering family-practice residencies fell by 50 percent, as young doctors headed for more-lucrative specialties like orthopedic surgery and radiology. “The problem is, primary care has never been loved by the deans of medical schools or by the teaching hospitals,” says Dartmouth’s David Goodman. As the total number of doctors rises and the proportion of primary-care doctors falls, we’re likely to see the quality of care deteriorate further and the cost of care increase rapidly.

The imbalance between specialists and primary-care physicians could be mitigated by changes in physician pay. Medicare, for instance, could raise its low reimbursement rates for primary-care visits (and lower its rates for specialist services), so that more young doctors would view primary care as an attractive career. Two primary-care professional organizations have proposed a plan to ensure that every patient has a primary-care physician, who is paid extra to coordinate the patient’s various doctors. In the meantime, patients might want to pay attention to the mix of doctors at their local hospital and compare how the quality of care measures up.

As for the rising number of physicians being trained, the remedy is simple: Turn the spigot back off, or at least close it partway. The groups now calling for more physicians should come up with better evidence that all those new doctors are not going to simply drive up costs.