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More female doctors and changes in where health-care delivered has fueled a decline in physician support for the GOP over the past 20 years, a new study finds. (Patrick Fallon/Bloomberg)

There have a few been recent hints at how the sweeping changes within the medical industry are reshaping the politics of being a doctor. But a new study suggests a profession once solidly aligned with Republicans has become more Democratic in the past 20 years, as the number of female doctors grows and the traditional small physician's office is on the wane.

Researchers analyzing doctors' federal campaign contributions between the 1991-92 and 2011-12 election cycles found that doctors — who once contributed to Republican campaigns at consistently higher rates than the entire donor population — have become less enthusiastic donors to the GOP.

In the last three election cycles, physician donations to Republicans have instead closely tracked to those made by the general population, according to JAMA Internal Medicine study authors Adam Bonica of Stanford University, Howard Rosenthal of New York University, and David J. Rothman of the Columbia College of Physicians and Surgeons.

(JAMA Internal Medicine)
(JAMA Internal Medicine)

That political shift may seem counter intuitive, though. The study authors note that doctors' contributions to Republicans increased in the 1993-94 and 2009-10 campaign cycles in response to Democratic health-care reform efforts — first, President Clinton's failed attempt and then the 2010 Affordable Care Act. Republicans also account for 16 of 20 current members of Congress who also hold medical degrees.

But there's growing polarization among doctors, the study authors found. Women contributed less to Republican candidates in the 2011-12 election cycle compared to 1991-92 (23.6 percent versus 30.9 percent), and physicians working in nonprofit organizations contributed less (25.6 percent versus 40 percent) in the same time period.

Doctors in higher-earning specialties were also more likely to donate to Republican candidates. Surgeons, who donated 32.7 percent more to Republican candidates than pediatricians did in 1992, donated 48.1 percent more than pediatricians in the 2012 election cycle.

The larger question is what these changing politics mean for the future of health-care policy. That's still uncertain, note the study authors, who write:

Now that the medical profession sits on both sides of the political aisle, will the Republican and Democratic parties devote unprecedented energy and shape policy to attract physician loyalty? Or will the increasing polarization of the profession increase the political participation of physicians even as it reduces the ability of physicians to reach consensus on health care policy?

On one hand, there was notable progress earlier this year on long-sought reform of Medicare's flawed policy for reimbursing doctors — though a bipartisan bill has been stalled as lawmakers can't agree on how to pay for the legislation. Meanwhile, Republican doctor-lawmakers have been some of Obamacare's loudest critics, and more doctors launched congressional bids this year.

One thing is certain: doctors in the past 20 years have become much more active participants of the political process. The percentage of active physicians who donated to federal campaigns increased from 2.6 percent in 1991-92 to 9.4 percent in 2011-12, researchers found.

Top health policy reads from around the Web:

The individual market grew under Obamacare. "The Kaiser Family Foundation estimates between 3 million and 3.5 million new people signed up for health insurance either through insurance companies or brokers in March. It estimates a total of 15 million people now have individual insurance through the private market. ... Kaiser’s findings suggest that the number of people purchasing health insurance grew even accounting for people who saw their existing plans canceled because of new requirements under ObamaCare." Ferdous Al-Faruque in The Hill.

The large federal exchange was an accident. "The federal option was supposed to be a limited and temporary fallback. But a shift to a bigger, more permanent Washington-controlled system is instead underway — without preparation, funding or even public discussion about what a national exchange covering millions of Americans means for the future of U.S. health care. It’s coming about because intransigent Republicans shunned state exchanges, and ambitious Democrats bungled them." Kyle Cheney and Jennifer Haberkorn in Politico.

States are giving narrow networks a close look. "Prompted by the health care overhaul law, several states are updating their rules for insurance networks to better reflect who is covered and how people shop for and use their benefits. Washington state just implemented new regulations, and discussions are underway in several others, including Arkansas, Minnesota, California and New Hampshire. Although complaints about one insurer's network prompted New Hampshire's decision to reconsider its rules, insurance officials say the old standards haven't kept up with changes in how and where people get health care." Holly Ramer in the Associated Press.