In spite of public health efforts to curtail unnecessary antibiotic prescriptions, the medications are still being prescribed at shockingly high levels in outpatient clinics and doctors’ offices, a new study at Washington University School of Medicine in St. Louis finds.
The scientists crunched de-identified data provided by Express Scripts Holding Co., a company that oversees drug benefits for employers, and determined 98 million outpatient antibiotic prescriptions were dispensed by 39 million individuals over three years from 2013 through 2015. Additionally, the scientists saw no reduction in the total prescription rate of antibiotics between those three years.
By suggesting that we’re not adhering to existing guidelines for the prescribing of antibiotics, this research implies that physicians are not strictly following the recommendations,” said study first author Michael Durkin, MD, assistant professor of medicine. “If they were, then we should have observed declining rates of antibiotic prescribing over time. This is worrisome because excessive antibiotic use is expensive and leads to the development of drug-resistant superbugs.
The research appears March 8 in the journal Infection Control & Hospital Epidemiology.
The researchers monitored prescription rates monthly for all antibiotics, as well as the five most frequently prescribed ones in the outpatient environment: azithromycin, amoxicillin, amoxicillin/clavulanate, ciprofloxacin, and cephalexin.
The average yearly number of prescriptions for antibiotics was 826 for every 1,000 beneficiaries. The study indicated a drop in such rates slightly in 2014 and an increase slightly in 2015. However, overall fluctuations were not significant statistically.
The researchers did find that there were seasonal changes in antibiotic prescriptions for outpatients. They recorded 8,000 to 9,000 monthly antibiotic prescriptions during winter and fewer than 6,000 during summer months, Durkin said. “Such an increase might be warranted in the winter, when infections from bacteria are prevalent; however, there also is concern that a lot of these antibiotic prescriptions are written inappropriately for viral infections, which tends to do more harm than benefit.”.
The CDC estimates that as many as 30 percent of antibiotic prescriptions in outpatient clinics are unnecessary, including those for sore throats and sinus infections, which are most commonly caused by viruses.
“The findings of the study are disappointing,” said Durkin, co-leader of the Antimicrobial Stewardship Program at Barnes-Jewish Hospital. “Most attempts at optimizing antibiotic prescribing in the past have been predicated on issuing guidelines to health-care practitioners via journal publications or websites. But it is unclear whether publication of recommendations is enough to alter practice. We need to do more to inform physicians.”
Another issue caused by overuse of antibiotics is unnecessary health-care expenses. In the present study, for example, the researchers estimated the average annual cost of antibiotics per beneficiary at $23. That figure might appear small, but it translates into almost $1 billion a year.
In drug costs alone, the U.S. spends roughly $9 billion a year on antibiotics,” Durkin said. “If 30 percent of the prescriptions are unnecessary, this equates to spending roughly $3 billion on unnecessary antibiotics. The medical impact of antibiotic overuse, such as hospitalizations, contributes to unnecessary health-care costs.
Durkin cited a number of limitations in the studies, including data that did not account for uninsured patients and patients paying cash for their prescriptions. The data also didn’t contain specific clinical data to ascertain whether antibiotics were appropriate.
“Future research by our research group will be done to find and learn the gap between current antibiotic prescribing in the community and clinical practice guidelines,” Durkin said.
The research is “novel and important,” the study’s senior author, Victoria J. Fraser, MD, the Adolphus Busch Professor of Medicine and director of the Department of Medicine at Washington University, and physician-in-chief at Barnes-Jewish Hospital, explained. “This research presents necessary information that can be applied to refine antibiotic prescribing habits. Efforts to optimize antibiotic utilization is the key to stop the epidemic of antibiotic resistance, which has direct causation from exposure to antibiotics.
