New Trends Study Highlights the Good, the Bad, and the Ugly Sides of Global Antibiotic Usage: Public Health Watch

When it comes to trends in antibiotic usage worldwide, there’s good news and bad news, at least based on the findings of a study posted on March 26th by the journal Proceedings of the National Academy of Sciences (PNAS).

Researchers from the Center for Disease Dynamics, Economics and Policy (CDDEP) in Washington, DC, examined global trends in antibiotic use between 2000 and 2015 with the idea of informing policies aimed at reducing improper prescribing and, by extension, the threat posed by resistant pathogens. The authors used pharmaceutical sales data in 76 countries worldwide.

Troublingly, in an age when antibiotic stewardship has been a point of emphasis within the field, the analysis revealed that defined daily doses of drugs increased by 65%, from 21.1 billion to 34.8 billion, over the course of the study period. It also found that antibiotic consumption increased by 39%, from 11.3 to 15.7 defined daily doses per 1000 inhabitants per day, over the same period.

“There is no question that in most high-income countries the rate of antibiotic use is too high,” study co-author Eili Klein, PhD, Assistant Professor, Department of Emergency Medicine, Johns Hopkins University School of Medicine, and a fellow at CDDEP, told Contagion^®. “Even when therapy is necessary, there is debate about which drug is the best option and what duration of time a patient should take an antibiotic. Realistically, providers need to examine their own practice and understand that the individual choices they are making are contributing to a global problem. Globally, we need to consider how to best facilitate reductions in use while balancing access issues.”

Interestingly, Dr. Klein added that he and his colleagues were not surprised by their findings; rather they were “disappointed.” Although he lauded recent “inroads” into addressing the issue of over-prescribing in high-income countries, he noted that “this is a multi-faceted problem and multiple issues have to be addressed in order to reduce consumption.” Indeed, the analysis found that, within high-income countries, antibiotic consumption increased by 6%, from 9.7 billion to 10.3 billion defined daily doses, while the consumption rate decreased by 4%, from 26.8 to 25.7 defined daily doses per 1000 inhabitants per day, over the 15-year study period. Overall, based on their projections, the authors of the PNAS paper believe antibiotic consumption will increase by as much as 200% by 2030.

“Unfortunately, there is no silver bullet, and as with other issues requiring collective action, it is difficult to get individuals to change their behavior when they don't see the direct causes of their actions,” Dr. Klein continued. “In other words, 1 prescription more is not a big deal in terms of resistance, same as 1 additional mile driven is not a big deal for climate change. However, if everyone has an additional prescription, that adds up to a lot of pressure on the pathogens to evolve resistance.”

Within the context of other research findings released recently, the conclusions of the PNAS study are even more disturbing. For example, an analysis of health care costs related to the treatment of diseases caused by antibiotic-resistant pathogens, published on March 21st by the journal Health Affairs, reveals that spending on affected patients has doubled since 2002 and now exceeds $2 billion annually. And, as further evidence that at least some providers may not be getting the stewardship message, an assessment of the duration of antibiotic therapy for sinusitis, published on March 26th, by JAMA Internal Medicine, found that the median duration of treatment following 3.7 million doctor visits was 10 days. As the authors of this paper note, Infectious Disease Society of America guidelines currently recommend 5 to 7 days of antibiotic therapy for sinusitis.

So what’s the good news? Well, the analysis by Dr. Klein and his colleagues suggests at least a portion of the global antibiotic consumption increases could be attributed to increases in gross domestic product (GDP) per capita growth in low-income and middle-income countries, which may be a sign that access to needed medicines in these regions may be improving. In these countries, antibiotic consumption increased by 114%, from 11.4 billion to 24.5 billion defined daily doses, over the study period.

“Most lower-income countries still have antibiotic consumption rates that are far lower than in high-income countries,” Dr. Klein explained. “Increases in those countries, which we found were correlated with economic growth, suggest that individuals with treatable infections are getting access to medications they may not have been able to before. So that component is good. The difficult question is how to balance increasing access in lower-income countries, which is desperately needed in certain areas, with reducing global consumption.”

Based on their findings, the authors of the PNAS analysis suggest that future policies need to focus on safely and effectively reducing global antibiotic consumption while still increasing access in countries where such options are desperately needed. One way to accomplish this, they believe, is to focus on disease prevention, particularly in high-income countries, which already have distinct advantages over their low- and middle-income counterparts in terms of access to clean drinking water and stable health care infrastructures.

“Investments in infrastructure and sanitation may be a more cost-effective manner to conserve our antibiotic armamentarium than investing in new drugs,” Dr. Klein said. “In addition, vaccines can prevent antibiotic use both directly through vaccination against bacterial diseases, and indirectly by reducing non-bacterial diseases, such as viruses like the flu, that often get treated with antibiotics.”

Proof there’s truth in the old cliché that an ounce of prevention is worth a pound of cure.

Brian P. Dunleavy is a medical writer and editor based in New York. His work has appeared in numerous health care-related publications. He is the former editor of Infectious Disease Special Edition.