First, an honest confession, Mike’s tweet had nothing to do with antimicrobial stewardship, but rather contact precautions. But his point is just as valid when discussing antimicrobial stewardship and there will come a time when forces will align to question the benefits and costs of stewardship programs since now and in the future they will lack the “necessary” cluster-randomized trial evidence supporting their existence.
There is a longer discussion to be had here sometime in the future, when I’m not writing a Center grant renewal, but the key question is what we consider “high-level” evidence. For most de-implementation supporters and indeed most infection control and stewardship guideline authors, high-level evidence is synonymous with individual or cluster-randomized trials. They simply cannot accept non-randomized, quasi-experimental designs as evidence. It is gotten to the point that the recent CDI Guidelines completely excluded quasi-expermintal designs from their level of evidence figure, despite the fact that one of the original Grade Criteria papers lists QE studies in its table and allows them to be ranked higher than RCTs, if certain criteria are met.
OK. So why am I rambling on about level of evidence and misapplying a tweet from 2 weeks ago? There was a new systematic review just published in AJIC by Leandro Bertollo and colleagues that asked the question: “Are antimicrobial stewardship programs effective strategies for preventing antibiotic resistance?” To answer this question they reviewed all studies published between from January 2012 to January 2017 and followed the standard PRISMA statement recommendations for reporting their findings.
Results: They identified and extracted data from 26 studies, of which 22 were single-center and four were multicenter studies. Study designs are listed in Table 2, below, with the special note that none of the before/after studies included a contemporaneous, unexposed control group. A major concern that the authors identified was that in 7 of the 26 studies (30%), there was evidence that infection control interventions were implemented at the same time as the stewardship intervention and that the majority (57%) of the stewardship studies that reported positive results were confounded by simultaneous implementation of new infection control practices. High fives for hand hygiene.
The need for more studies. Sounds like the siren call for de-implementation to me. Sure, we can wait around a decade or four for some magical $20 million cluster-randomized study that swabs all patients on admission/discharge, completes a full microbiome analysis and tracks patients for a year post discharge for resistant infections. Or, we can expand our ideas around what “high-level” evidence means and fund well-designed and controlled quasi-experimental studies and also consider strong epidemiological evidence, such as exposure to antibiotics leads to colonization with resistant pathogens. We can be logical. Yeah, not gonna happen. But at least you were warned.