Potential impact of outpatient stewardship interventions on antibiotic exposures of bacterial pathogens

Abstract

The relationship between antibiotic stewardship and population levels of antibiotic resistance remains unclear. In order to better understand changes in selective pressure due to stewardship, we use publicly available data to estimate the effect of changes in prescribing on exposures to frequently used antibiotics experienced by potentially pathogenic bacteria that are asymptomatically colonizing the microbiome. We quantify this impact under four hypothetical stewardship strategies. In one scenario, we estimate that elimination of all unnecessary outpatient antibiotic use could avert 6 to 48% (IQR: 17 to 31%) of exposures across pairwise combinations of sixteen common antibiotics and nine bacterial pathogens. Across all scenarios, we find that successful stewardship interventions, facilitated by changes in clinician behavior and improved diagnostics, have the opportunity to substantially reduce exposures across a wide range of antibiotic-organism combinations. Concurrent approaches, such as vaccines aiming to reduce infection incidence, are needed to decrease exposures occurring in 'necessary' contexts.

Impact of antibiotics to off-target infant gut microbiota and resistance genes in cohort studies

“…Due to challenges in diagnosis, gastrointestinal consequences of antibiotics, and concern for the growing threat of antimicrobial resistance, many country-level antibiotic stewardship protocols encourage watchful waiting 41 . Accordingly, randomized controlled trials 29,42 and population-level cross-sectional studies 27,43 have examined delayed, shortened, or no antibiotic therapy for uncomplicated otitis media and respiratory infections 29,42 . While these studies are critical, cohort studies with combined covariate and microbiome data also yield valuable evidence in support of antibiotic stewardship practices because they reflect current treatment practices.…”

“…Few studies have attempted to quantify relationships between antibiotic use, off-target microbes, and the spread of antibiotic resistance 10,27 . These studies were limited in that they were cross-sectional or ecologic in design, did not consider antibiotic exposure and microbiome data from the same individuals longitudinally over time, and did not assess ARGs directly.…”