Research snapshot: Thirty percent of antibiotic prescribing unnecessary

May 5, 2016

Antibiotic resistance is a growing health concern in the United States, causing 23,000 fatalities annually from exposure to harmful effects, according to the Center for Disease Control (CDC). Excessive antibiotic use is the main driver for the resistance, leading the White House to implement the National Action Plan for Combating Antibiotic-Resistant Bacteria, which sets the goal of decreasing inappropriate antibiotic use by 50 percent by 2020.

School of Public Health Assistant Professor, Eva Enns, Ph.D., collaborated with researchers from the CDC and various colleges around the country to determine the number of outpatient visits in which antibiotics were inappropriately prescribed. They found an estimated 30 percent of outpatient antibiotic prescribing was unnecessary in 2010-2011.

The study, published in the Journal of American Medical Association (JAMA), involved data from a nationally representative survey of outpatient healthcare visits, showing nearly 262 million total outpatient antibiotic prescriptions were sold throughout the entire year. Looking at clinical guidelines and geographic variation, the researchers then estimated the proportion of antibiotics prescriptions that were likely inappropriate for each of these conditions.

“Antibiotic resistance is increasing – we are seeing the emergence of infections that are resistant to all available treatments,” said Enns. “Luckily these are still rare, but MRSA, one of the most publicized cases of antibiotic resistance, was once a rare occurrence, too, limited to inpatient settings. But now we’re seeing it more and more, even in community settings.”

Some antibiotic use is necessary, but Enns says eliminating antibiotic prescribing when they are not needed and not beneficial is low hanging fruit for reducing the growth of antibiotic resistance.

“Antibiotic resistance is an inevitable consequence of antibiotic use, both appropriate or inappropriate,” said Enns. “The key is to conserve antibiotics for the cases in which they are truly needed.”

The research offers a baseline for which the National Action plan can compare progress in reducing inappropriate prescriptions and the analysis framework can be used to monitor how prescribing has changed in future years.

Results from the analysis hinge on the accuracy diagnostic codes, which were used to classify antibiotic prescriptions as appropriate or inappropriate, or simply put, prescribing an antibiotic for a disease that hasn’t been officially diagnosed.

“For prescribers, we try to make the point that prescribing antibiotics is not without consequences and should not be used ‘just in case’,” said Enns. “If they believe an antibiotic would be beneficial, they should provide the diagnosis that would justify it.”