The link between more doctors and antibiotic resistance

A huge number of people could die over the next four decades as a result of diseases resistant to antibiotics.

And your family doctor's desire to keep you from going to a physician at a retail clinic—at least if you live in a ritzy area of town—could be making things worse.

The possibility of that intriguing connection is suggested by two separate studies related to the growing problem of antibiotic resistance throughout the world.

The problem, linked to the overuse of antibiotics and a quarter-century drought of new antibiotic development, recently led President Barack Obama to call for doubling U.S. spending on combating resistance to the commonly prescribed medications to more than $1.2 billion.

One new study highlights the potentially massive human and economic toll from the continued spread of diseases that don't respond to antibiotics.

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That analysis by the RAND Corporation, which looked at seven scenarios, estimates that "the world population by 2050 will be between 11 million and 444 million lower than it would have been otherwise in the absence of" antimicrobial resistance "if the problem is not tackled."

"The lower bound is a result of a scenarios where resistance rates have been successfully kept at a relatively low rate, while the upper bound reflects a scenario for a world with no effective antimicrobial drugs," according to RAND Europe, which was commissioned to study the issue by the Independent Review of Antimicrobial Resistance.

And the world economy would see a cumulative loss of $2.1 trillion to $124.5 trillion by the year 2050 due to deaths and prolonged periods of sickness affecting labor efficiency, according to the scenarios analyzed by RAND. "We estimate that by 2050 the world economy would be smaller by between 0.06 percent and 3.1 percent again depending on the scenario."

Doctor writing prescription
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The other study suggests that in wealthier areas of the United States, competition between doctors and the retail clinics often known as "doc-in-a-box" sites leads to higher rates of doctors writing prescriptions for antibiotics, which in turn can fuel resistance to those drugs.

That study published in the Journal of Antimicrobial Chemotherapy "found that the availability of urgent care and retail clinics is an important factor in driving prescribing rates," wrote lead author Eili Klein in a blog post detailing the results.

"The number of clinics greatly increased between 2000 and 2010," noted Klein, assistant professor in the Emergency Medicine department at Johns Hopkins University. "What we found was that in low-income areas, a clinic increased the prescribing rate, but it didn't affect the rate that physicians were prescribing antibiotics."

"However, in wealthier areas, we found that a clinic actually increased the rate of prescribing by physicians. The mechanism for this though may not have been an increase in the probability of getting an antibiotic at any single visit, but rather the increased availability of physicians," he wrote. "Evidence has shown that when clinics enter an area, physician offices change their operations, creating more walk-in slots and same-day appointments."

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"These 'competitive' actions increase the opportunities for people to access the physician and thus drive up the rate of prescribing."

Last week, a third study found differences in the way certain physicians prescribe—and mis-prescribe—antibiotics.

That study, published in the Infection Control & Hospital Epidemiology journal, found that 45 percent of patients with infections of the respiratory tract were inappropriately prescribed antibiotics over a two-year period while being treated on an outpatient basis at Boston Medical Center's general internal medicine and family medicine practice.

The study noted that in ambulatory care settings, antibiotics are often incorrectly prescribed for respiratory tract infections, which "often do not require antibiotic interventions," according to the Society for Healthcare Epidemiology of America.

"Physicians' inappropriate prescribing patterns appeared to differ by medical specialty and to be established early, likely during medical school or residency," said Dr. Tamar Barlam, lead author of the study and director of the Antimicrobial Stewardship Program for Boston Medical Center.

"Instituting aggressive interventions in training or practice at the right time and to the right physicians could improve antibiotic use and efficacy of antibiotic stewardship in outpatient settings," Barlam said.

The three studies come as the Obama administration has focused renewed attention on the problem of antibiotic-resistant diseases.

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In a fact sheet distributed in late January by the White House, the administration noted that the federal "Centers for Disease Control and Prevention estimates that each year at least 2 million illnesses and 23,000 deaths are caused by antibiotic-resistant bacteria in the United States alone.

"Antibiotic-resistant bacteria also pose economic threats," the fact sheet said. "The CDC reports that antibiotic-resistant bacteria infections account for at least $20 billion in excess direct health-care costs and up to $35 billion in lost productivity and hospitalizations and sick days each year."

Last September, Obama signed an executive order launching federal efforts to stem the spread of antibiotic-resistant bacteria.

"This is an urgent health threat, and a threat to our economic stability, as well," said CDC Director Dr. Thomas Frieden at the time.

"Antibiotics are among the most commonly prescribed drugs in medicine," Frieden said. "But either half are not needed or are not optimally prescribed."