In the last few years, we've finally seen a number of moves taken by the federal government to address the growing crisis of antibiotic resistance in the United States. But we in the medical and health community have known about this issue for a much longer time. We would think, therefore, that we have been making progress in reducing antibiotic use in the hospital. We would, unfortunately, be mistaken.
In a recent study published in JAMA Internal Medicine, researchers used the Truven Health MarketScan Drug Database to monitor the use of antibiotics in the inpatient setting between 2006 and 2012. The database houses discharge records from about 300 participating hospitals that are weighted to represent the US at large. Data were abstracted for any doses of antibiotics administered orally, parentally, or by inhalation. Antibiotics were further classified into fifteen categories.
Antibiotic use was calculated as both days of therapy per 1000 patient days and by the proportion of discharges where a patient received at least one dose of an antibiotic during their stay. Individual antibiotics counted only once a day, even if they were given more than once a day. In order to validate their results, they compared them to data derived from the Healthcare Cost and Utilization Project National Impatient Sample.
From 2006 through 2012, more than half of all patients admitted to hospitals received at least one dose of antibiotics. The overall days of therapy was 755 per 1000 patient days. What's more disappointing was that the use of antibiotics did not change over time.
Given the fact that we know antibiotics are used inappropriately much of the time, one might hope that their use had decreased. That's just not the case. There were, however, changes in which types of antibiotics were used.
Fluoroquinolones, and first- and second- generation cephalosporins did decrease in use. Others, however, increased. Vancomycin use went up 32%. Agents with broad-spectrum activity against gram-negative bacteria, including carbapenem, third- and fourth-generation cephalosporins, and ?-lactam/?-lactamase inhibitor combination antibiotics also increased significantly. Moreover, although Fluoroquinolone use went down over time, that class of drugs was still the most commonly used of all antibiotics in hospitals in the United States.
Of course, the authors can only speculate as to the reasons these changes occurred. They hypothesize that decreases in fluoroquinolones, for instance, are due to concerns about Clostridium difficile infections, or because we've seen more resistance in bacteria to those specific antibiotics recently. Increases in third- and fourth-generation cephalosporins, ?-lactam/?-lactamase inhibitor combinations, and carbapenem may be indicative of worries about infections caused by resistant gram-negative bacteria.
But they note that antibiotic use in the United States differs significantly from that in the UK and France. We seem to use far more broad spectrum antibiotics. They use many more penicillins.
This has consequences. Broad spectrum antibiotics are more likely to lead to wider resistance. Overuse of antibiotics, in general, will as well. We all know that we need to do a better job, but we knew that a decade ago, too. It's possible that things have improved since 2012, when these data end. It would be unwise of us to just assume that, though.
–Aaron