Reducing Antibiotic Use Cuts Hospital-Onset C Diff Infections

Decreased use of antibiotics is associated with reductions in hospital-onset Clostridium difficile (C diff) infection, according to a new study released by the US Centers for Disease Control and Prevention (CDC).

"The effect of antibiotics on increasing risk for [C diff] in patients has been well documented, but what this study adds is that antibiotic use on the population level (within a hospital) is associated with hospital rates of [C diff]. Specifically, hospitals with higher rates of total inpatient antibiotic use were found to have higher rates of [hospital-onset C diff]," Sophia Kazakova, MD, MPH, PhD, from the Division of Healthcare Quality Promotion at the National Center for Emerging and Zoonotic Infectious Diseases at the CDC, and a corresponding author of the study, told Contagion^®.

The study, which looked at data from more than 500 acute care hospitals in the United States between 2006 and 2012, also found that the specific antibiotic classes—third- and fourth-generation cephalosporins and carbapenems—were associated with higher rates of hospital-onset C diff. It was the largest ecological investigation of the association to date.

Those acute care hospitals that saw significant decreases in antibiotic use also saw significant reductions in hospital-onset C diff.

"It was surprising to find how strongly the levels of antibiotic use and [hospital-onset C diff] correlated and represented almost a 'dose-response'-like relationship, where 20% or larger decrease in total antibiotic use corresponded with 22% decrease in [hospital-onset C diff] and 30% or larger decrease corresponded with 33% decrease in [hospital-onset C diff]," Dr. Kazakova told Contagion^®.

Although very few acute care hospitals saw such large reductions in antibiotic use, Dr. Kazakova said that "for the hospitals with high levels of antibiotic consumption, this can be an inspirational finding.”

Dr. Kazakova also said that between 20% and 50% of all antibiotics used in hospitals are unnecessary or inappropriate.

The CDC established "core elements" of antibiotic stewardship programs, which have been incorporated in hospital certification programs, leading to an increase in such programs, with 75% of hospitals reporting that they had antibiotic stewardship programs in 2017, up from 40% in 2014. More research is needed to determine how antibiotic use is changing at those hospitals.

"Antibiotics can be life-saving for hospitalized patients, but they can also cause harm—not only to the treated individual, but also to other patients in that hospital," Dr. Kazakova said in the interview. "For instance, if a patient who is carrying [C diff] receives antibiotics, that patient may become more contagious and shed more [C diff] into the environment leading to transmission to other patients. Better use of antibiotics reduces risk of [C diff] infections for every hospitalized patient."

The study found moderate association with fluoroquinolone, and recommended targeting antibiotic stewardship programs to high-risk antibiotic classes as an alternative to targeting total antibiotic use. Other studies have suggested using penicillin-based antibiotics instead of flouroquinolones and cephalosporins, and more research is needed to determine the results of such efforts and their effect on C diff rates.

Safety concerns have led regulatory agencies to issue warnings about the use of fluoroquinolone antibiotics. Last year, the safety committee of the European Medicines Agency (EMA) recommended restricting the use of fluoroquinolone and quinolone antibiotics. The US Food and Drug Administration and Health Canada also have issues warnings.

Antimicrobial stewardship programs were supported by a study that found that de-escalation within 48 hours of broad-spectrum antibiotics reduced the incidence of C diff infection.