Nearly half of office-based physicians work with NPs and PAs

Almost one in two office-based physicians works in a practice that includes physician assistants, nurse practitioners and/or certified nurse midwives. And that number is expected to go up.

The Centers for Disease Control and Prevention's National Center for Health Statistics reported in an Aug. 17 data brief that 49% of physicians working in office settings have the practitioners on board. The most likely to work with them: doctors age 54 and younger, those in large groups and those serving a large Medicaid population.

This government agency does not have historic data, but organization insiders and other experts believe physicians will only be more likely to work with these clinicians in the future.

"We know that more practices are relying on midlevel providers because of increasing demand for health care services," said Melissa Park, MPH, lead author of the report and an NCHS researcher. "The demand is just going to increase in the years to come."

Among the reasons are increasing physician shortages as health care demand goes up, a need to fill in for residents with restricted work hours, and further consolidation of practices into larger groups as a result of health system reform.

There were 737,764 physicians in the U.S. in 1996, and this grew to 954,224 in 2008, an increase of more than 29%, according to the American Medical Association's annual report on physician characteristics and distribution.

The number of allied practitioners expanded at a much faster rate. There were 70,993 nurse practitioners in 1996 compared with 158,348 in 2008, a growth of 123%, according to the Health Resources and Services Administration. The number of physician assistants went up from 29,161 in 1996 to 73,893 in 2008, an increase of 153%, according to the American Academy of Physician Assistants.

"The number of practicing physicians has not really kept up with greater demand," said Richard Muma, PhD, MPH, a physician assistant and associate provost at Wichita (Kan.) State University.

The disparity is even wider with regard to primary care physicians. Their number grew from 294,471 in 1996 to 305,264 in 2008, an addition of less than 4%.

Primary care is the most likely specialty to work with midlevel practitioners. About 55.4% of primary care doctors worked with at least one nurse practitioner, physician assistant or certified nurse midwife, but this was true for only 45.9% of surgical specialists and 40.8% of medical specialists, according to the NCHS report.

"It really works quite well in the patient-centered medical home, collaborative practice model that we have been promoting," said Glen Stream, MD, who was scheduled to become president of the American Academy of Family Physicians on Sept. 14. "In an integrated team, each professional is practicing up to their level of skill and training and doing a better job of taking care of a population of people."

Practice factors

Only 37.6% of primary care doctors in a solo or two-physician practice worked with at least one nurse practitioner, physician assistant or certified nurse midwife, but this went up to 79.9% for groups of 11 or more, according to the NCHS report.

Age also was a factor as to whether a physician was working with a midlevel practitioner. The NCHS report found that 51.2% of physicians under 45 worked with midlevel practitioners, but this was true of only 43.5% of doctors 55 and over.

"A number of physicians are actually training with physician assistants these days," said Michael Powe, vice president of reimbursement and professional advocacy with the American Academy of Physician Assistants. "They're often in the same classroom, and that increases the comfort level."

Experts say the use of midlevel practitioners has grown because it takes much less time to educate them and they are paid less than physicians. For instance, the NCHS survey found that midlevel practitioners were more common at practices that received a greater proportion of income from Medicaid, which tends to have low payment rates compared with other insurance. A total of 53.0% of practices with a high percentage of revenue from Medicaid employed midlevel practitioners, but this was true for only 45.4% of practices with a high level of Medicare payments and 50.9% with a high level of private insurance payments.

Other surveys suggest that the economics of health care play a significant role in the use of midlevel practitioners. A study published online May 9 in the American Journal of Medical Quality that looked at physician assistants and nurse practitioners at academic medical centers found that the main reason was to deal with resident duty hour restrictions. The most common secondary reason was to increase the number of patients seen.

Although nonphysician practitioners have become common in the health system, their scope of practice is a source of tension.

Most physician societies, including the AMA, support their incorporation as part of care teams but don't want them practicing without physician supervision or collaboration. Fifteen states allow advanced practice nurses to practice independently of physicians. In the past decade, 16 states opted out of the federal rule mandating physician supervision of certified registered nurse anesthetists administering anesthesia at hospitals who participate in Medicare.

"Physicians, nurse practitioners, physician assistants and other health care professionals work well together, and these physician-led teams provide the most advantageous care for patients," AMA President Peter W. Carmel, MD, said. "As the [NCHS] study points out, with millions more Americans expected to receive coverage under the [Patient Protection and Affordable Care Act], physician-led health care teams are the optimal solution to ensure that patients receive the right care at the right time in the right setting."

Family physician Jose De Jesus, MD, works with a nurse practitioner at San Antonio's WellMed Medical Group, which has 60 primary care physicians in Texas and Florida. Dr. De Jesus reviews her charts, but she makes house calls to his patients and covers for him when he is out.

"She complements what I do in the clinic, and I am able to see more patients," Dr. De Jesus said. "Physicians have a tendency to think of themselves as the king of the mountain. There's room on the mountain for everybody."