Trends in U.S. Burden of Clostridioides difficile Infection and Outcomes

Abstract

Background: Efforts to prevent Clostridioides difficile infection continue to expand across the health care spectrum in the United States. Whether these efforts are reducing the national burden of C. difficile infection is unclear.

Methods: The Emerging Infections Program identified cases of C. difficile infection (stool specimens positive for C. difficile in a person ≥1 year of age with no positive test in the previous 8 weeks) in 10 U.S. sites. We used case and census sampling weights to estimate the national burden of C. difficile infection, first recurrences, hospitalizations, and in-hospital deaths from 2011 through 2017. Health care-associated infections were defined as those with onset in a health care facility or associated with recent admission to a health care facility; all others were classified as community-associated infections. For trend analyses, we used weighted random-intercept models with negative binomial distribution and logistic-regression models to adjust for the higher sensitivity of nucleic acid amplification tests (NAATs) as compared with other test types.

Results: The number of cases of C. difficile infection in the 10 U.S. sites was 15,461 in 2011 (10,177 health care-associated and 5284 community-associated cases) and 15,512 in 2017 (7973 health care-associated and 7539 community-associated cases). The estimated national burden of C. difficile infection was 476,400 cases (95% confidence interval [CI], 419,900 to 532,900) in 2011 and 462,100 cases (95% CI, 428,600 to 495,600) in 2017. With accounting for NAAT use, the adjusted estimate of the total burden of C. difficile infection decreased by 24% (95% CI, 6 to 36) from 2011 through 2017; the adjusted estimate of the national burden of health care-associated C. difficile infection decreased by 36% (95% CI, 24 to 54), whereas the adjusted estimate of the national burden of community-associated C. difficile infection was unchanged. The adjusted estimate of the burden of hospitalizations for C. difficile infection decreased by 24% (95% CI, 0 to 48), whereas the adjusted estimates of the burden of first recurrences and in-hospital deaths did not change significantly.

Conclusions: The estimated national burden of C. difficile infection and associated hospitalizations decreased from 2011 through 2017, owing to a decline in health care-associated infections. (Funded by the Centers for Disease Control and Prevention.).

Figure 1.. Percentage of Cases of Clostridioides difficile Infection (CDI) Diagnosed by Means of NAAT at 10 U.S. Emerging Infections Program Sites, 2011–2017.

Diagnosis of CDI by nucleic acid amplification test (NAAT) was defined as a positive C. difficile stool test conducted with the use of NAAT alone or with a multistep testing algorithm in which NAAT was almost always the last test performed. The non-NAAT methods that were used by participating laboratories consisted primarily of an enzyme immunoassay for toxins, used either alone or in combination with an enzyme immunoassay for glutamate dehydrogenase. Less than 1% of participating laboratories used other methods, such as the cell-culture cytotoxicity neutralization assay.

Figure 2 (facing page).. U.S. National Estimates of the Burden and Incidence of Community-Associated CDI, Health Care–Associated CDI, and Total CDI, 2011–2017.

The estimates of the actual national burden and incidence for each year are based on the actual rate of use of the nucleic acid amplification test (NAAT) in that year, with adjustment for the age, sex, and race of the U.S. population. The estimates of the adjusted national burden and incidence for each year are based on an adjustment of NAAT use to the 2011 rate of 55%, with additional adjustment for the age, sex, and race of the U.S. population. The estimates of the national burden of community-associated CDI and health care–associated CDI do not always add up to the estimated total burden of CDI because of rounding.