Studies examine impact of hospital policies on C. difficile infection rates

While one study found that participation in an antibiotic stewardship program from the Agency for Healthcare Research and Quality led to reductions in hospital-onset Clostridioides difficile infection rates, a simulation study found that visitor contact precautions may not be as helpful.

Two studies, both published Feb. 26 by JAMA Network Open, assessed the effects of hospital policies on Clostridioides difficile infection (CDI).

In the first study, the Agency for Healthcare Research and Quality Safety Program for Improving Antibiotic Use was associated with reductions in antibiotic use and hospital-onset CDI rates across participating hospitals. The program helped hospitals establish antibiotic stewardship programs and worked with frontline clinicians to improve their antibiotic decision making. All clinical staff (e.g., clinicians, pharmacists, nurses) were encouraged to participate. Seventeen webinars occurred over a one-year period, accompanied by additional educational content. Topics focused on establishing antibiotic stewardship programs, the science of safety, improving teamwork and communication, and best practices for the diagnosis and management of infectious processes. From Dec. 1, 2017, to Nov. 30, 2018, 437 U.S. hospitals were enrolled in the quality improvement study. The primary outcome was overall antibiotic use at the beginning (January and February 2018) versus the end (November and December 2018) of the program. A secondary outcome was quarterly hospital-onset C. difficile laboratory-identified events per 10,000 patient-days.

Of the 437 hospitals enrolled, 92% stayed in the program until its completion—7% academic medical centers, 30% midlevel teaching hospitals, 42% community hospitals, and 21% critical access hospitals. Adherence to key components of antibiotic stewardship programs (i.e., interventions before and after prescription of antibiotics, availability of local antibiotic guidelines, stewardship program leads with dedicated salary support, and quarterly reporting of antibiotic use) improved from 8% to 74% over the study period (P<0.01). Antibiotic use decreased by 30.3 days of therapy per 1,000 patient-days (95% CI, −52.6 to −8.0 days of therapy; P=0.008). Similar changes in antibiotic use were not observed in 614 hospitals in the Premier Healthcare Database from the same period. The incidence rate of hospital-onset C. difficile events decreased by 19.5% (95% CI, −33.5% to −2.4%; P=0.03).

Among other limitations, comparisons between the Safety Program and the Premier Healthcare Database cohort should be interpreted cautiously because some information was not available for hospitals contributing data to the latter, the authors noted. “The Safety Program was able to demonstrate that establishing [antibiotic stewardship programs] and training frontline clinicians may improve antibiotic use, even in hospitals without infectious diseases-trained physicians or pharmacists,” they wrote. “In fact, we were able to train clinicians—often staff pharmacists—to become stewardship leaders in their facilities.” An accompanying editorial called the effort the largest pragmatic quality improvement antimicrobial stewardship program initiative in the U.S. “We now have a practical framework for even small and low-resource hospitals to see a tangible and timely result from creation of an antimicrobial stewardship program and engagement in a handful of straightforward interventions,” the editorialists said.

The second study found less success against CDI with visitor contact precautions. Researchers conducted the simulation study between July 27 and Aug. 11, 2020, by modeling C. difficile transmission in a 200-bed acute care adult hospital. The model simulated hospital activity for one year among a homogeneous adult population and compared no visitor contact precautions with ideal use of contact precautions under varying assumptions about patient susceptibility, behavior, C. difficile transmission, and other factors. The main outcome was the rate of hospital-onset C. difficile infection per 10,000 patient-days.

In the simulated model, the baseline rate of hospital-onset C. difficile infection was 7.94 per 10,000 patient-days (95% CI, 7.91 to 7.98 per 10,000 patient-days) with no visitor contact precautions compared with 7.97 per 10,000 patient-days (95% CI, 7.93 to 8.01 per 10,000 patient-days) with ideal visitor contact precaution use. Visitor contact precautions were not associated with a reduction of more than 1% in hospital-onset C. difficile infection rates in any of the tested scenarios and hospital settings. On the other hand, independently increasing the hand-hygiene adherence of the average health care worker and environmental cleaning adherence by no more than 2% each was associated with greater reduction in hospital-onset C. difficile infection compared with all other scenarios, including ideal implementation of visitor contact precautions.

Limitations of the study include its simulated design and that it did not consider the effect of community-onset C. difficile infection on hospital visitors, the authors noted. “In the context of these findings and financial and supply-chain constraints, the infection control community should reevaluate the value of VCPs [visitor contact precautions] for patients with CDI,” they concluded. “If this model is correct, removing VCPs, which are associated with minimal change in [hospital-onset] CDI rates, from prevention bundles may allow better allocation of resources for containment.”