SAN FRANCISCO – Physicians continue to inappropriately prescribe antibiotics for sore throat and bronchitis, according to analyses of data from the National Ambulatory Medical Care Survey and the National Hospital Ambulatory Medical Care Survey.

Doctors prescribed antibiotics in 60% of office visits for sore throats and 73% of visits for acute bronchitis. However, the antibiotic prescribing rate should be about 10% for sore throats – based on the prevalence of group A Streptococcus (GAS), the only common cause of sore throat for which antibiotics are indicated – and the rate should be almost zero for acute bronchitis, which is almost always caused by a virus, Dr. Jeffrey A. Linder reported during a press conference at an annual scientific meeting on infectious diseases.

The findings are based on cross-sectional analyses of the nationally representative surveys on visits by adults for either a sore throat or for acute bronchitis. The sore throat findings were based on 8,191 visits between 1997 and 2010.

The overall national antibiotic prescribing rate for sore throats did not change from 1997-1998 to 2009-2010, nor did the prescribing rate among office-based physicians or emergency departments during that time period.

Physicians reported increased prescribing of broad-spectrum, expensive, or nonrecommended antibiotics. However, prescriptions for penicillin – the antibiotic of choice for GAS – remained stable at 9% across the study period.

The bronchitis findings are based on surveys for 3,667 visits by adults with a diagnosis of acute bronchitis to primary care physicians and emergency departments between 1996 and 2010. The overall national antibiotic prescribing rate did not change during the study period, but the prescribing rate in emergency departments increased from 69% in 1996 to 73% in 2010, said Dr. Linder* of Harvard Medical School and Brigham and Women’s Hospital, Boston.

Also, physicians increasingly prescribed extended-spectrum macrolides across the study period, with such prescriptions provided at 25% of visits in 1996 and at 41% of visits in 2010, he noted.

Fluoroquinolones were prescribed at 11% of visits, aminopenicillins were prescribed at 7% of visits, and cephalosporins were prescribed at 7% of visits.

The findings were reported in posters at the combined annual meetings of the Infectious Diseases Society of America, the Society for Healthcare Epidemiology of America, the HIV Medicine Association, and the Pediatric Infectious Diseases Society. The sore throat findings were also reported concurrently online in the Oct. 4 issue of JAMA Internal Medicine (2013 [doi:10.1001/jamainternmed.2013.11673]).

"The really bad news here is that (the antibiotic prescribing) hasn’t changed at all across the course of the study ... looking back into how we’ve done over past 20 years or so, there’s a little improvement, but it’s painfully slow, and we’re still very far away from the appropriate rate of antibiotic prescribing," he said, noting that this is despite years of effort to promote antibiotic stewardship.

Based on a prior analysis, the antibiotic prescribing rate for sore throat dropped from about 80% to 70% around 1993, and dropped again to 60% by 2000. The current findings show that the prescribing rate remains stable at the 60% level.

Although there was some indication in the survey data that patients are being a little more selective in seeking care for these conditions – perhaps because they are beginning to understand that antibiotics aren’t effective for viral illness – the findings regarding prescribing are troubling, the investigators noted.

Recently, the Centers for Disease Control and Prevention reported that 2 million people are infected with antibiotic-resistant bacteria each year, and 25,000 of those patients die as a result. Antibiotic resistance also causes a great deal of "collateral damage," such as increasing rates of Clostridium difficile infection, said Dr. Ed Septimus, who moderated the press conference.

That results in huge societal costs, estimated at about $35 billion, said Dr. Septimus of Texas A&M Health Science Center, Houston.

Education and improved communication between doctors and patients are needed to address the problem, Dr. Linder and Dr. Septimus agreed.

"Patients and doctors need to have a conversation about the illness ... some of our research suggests that patients don’t want antibiotics as much as doctors think they do," Dr. Septimus said. Doctors often prescribe out of fear that patients will walk away unsatisfied if they don’t get a prescription, he added, but frequently patients just want reassurance that they don’t need an antibiotic.

Accountability is another factor lacking in the outpatient setting, he said.

"We as physicians need to take accountability for our actions ... we need to be reminded that antibiotics, for many of these conditions, are not indicated," he said.

Dr. Linder and Dr. Septimus reported having no disclosures.

*Correction, 10/9/2013: An earlier version of this story misspelled Dr. Linder's name.

Antibiotics are overprescribed for sore throat, bronchitis