Antibiotic use increases worldwide

Global antibiotic use has risen 36% over the last decade, according to a study published in the July 10 issue of The Lancet Infectious Diseases.

Princeton researchers conducted a broad assessment study of antibiotic consumption around the world. They used sales data for retail and hospital pharmacies from the IMS Health MIDAS database, and reviewed trends for consumption of standard units of antibiotics between 2000 and 2010 for 71 countries. The researchers used compound annual growth rates to assess temporal differences in consumption for each country and Fourier series and regression methods to assess seasonal differences in consumption in 63 of the countries.

They found that 5 countries-Brazil, Russia, India, China and South Africa (BRICS)-were responsible for more than three-quarters of that surge.

In the United States, antibiotic consumption has flattened compared with the 5 BRICS countries. But US citizens per capita still account for far more antibiotic consumption than any other population, with a rate of more than twice that of India.

Among the 16 groups of antibiotics studied, cephalosporins, broad-spectrum penicillins and fluoroquinolones accounted for more than half of that increase, with consumption rising 55% from 2000 to 2010.

“This specific study was primarily focused on retail sales data on antibiotics and we did not have hospital data on antibiotic sales for the United States,” said study author Ramanan Laxminarayan, PhD, MPH, Princeton Environmental Institute, Princeton University, Princeton, N.J.

“That said, managed care organizations in the United States that cover antibiotic costs are likely to see the study as somewhat good news because of the leveling off of consumption,” Laxminarayan told FormularyWatch. “However sales of newer antibiotics like carbapenems is increasing, partly in response to increasing drug resistance, and that will most likely increase costs for managed care organizations over time.”

The study quantifies the growing concern around antibiotic-resistant pathogens, and a loss of efficacy among antibiotics used to treat the most common illnesses. In addition, the study highlights an increasing resistance to carbapenems and polymixins, 2 drug classes long considered "last resort" antibiotics for illnesses without any other known treatment.

The data also underscore the fact that more global citizens are able to access and purchase antibiotics. However, that use is not being effectively monitored by health officials, from physicians to hospital workers to clinicians, noted the researchers. Consequently, antibiotic use is both rampant and less targeted.

"We have to remember that before we had antibiotics, it was pretty easy to die of a bacterial infection," said Laxminarayan in a Princeton press release. "And we're choosing to go back into a world where you won’t necessarily get better from a bacterial infection. It's not happening at a mass scale, but we're starting to see the beginning of when the antibiotics are not working as well."

Antibiotic use tended to peak at different times of the year, according to the study, corresponding in almost every case with the onset of the flu season.

Programs promoting "rational use" of antibiotics should be a national and global priority, said the authors. That process has to begin with the BRICS countries, which are experiencing the highest rates of increase in antibiotic consumption.