A pair of values-based incentive programs (VBIPs) implemented at US hospitals in recent years were associated with a decline in Clostridioides difficile infections, US researchers reported late last week in JAMA Network Open.
In a study of more than 24 million admissions at 265 hospitals over 6 years, the researchers found that two programs implemented by the Centers for Medicare & Medicaid Services (CMS) to reduce healthcare-associated infections (HAIs) were linked to an immediate 6% decline in hospital-onset C difficile (HO-CDI) rates and a sustained decline of 4%.
C difficile is the leading cause of hospital-associated diarrhea in the United States and one of several HAIs targeted by the US Department of Health and Human Services in a 2013 action plan. It sickened more than 223,000 hospital patients and was associated with 12,800 deaths and more than $1 billion in attributable healthcare costs in 2017.
Occurring mainly in people who've had both recent medical care and antibiotic exposure, C difficile is considered an urgent antibiotic resistance threat by the Centers for Disease Control and Prevention (CDC).
CMS has been attempting to cut HO-CDI and other HAIs through financial incentive programs that reward or penalize hospitals based on their rates of these infections, with mixed results. The authors of the study say this is the first HAI for which a CMS incentive program has been linked with improvement.
Immediate and sustained declines
Two of the VBIPs implemented by CMS to help hospitals reduce HAIs are the Hospital Value-Based Purchasing (HVBP) program and the Hospital-Acquired Conditions Reduction Program (HACRP). HVBP rewards or penalizes hospitals by as much as 2% of total Medicare inpatient payments based on how they perform on certain quality measures, while HACRP withholds as much as an additional 1% from the lowest-performing hospitals. In October 2016, the two programs began including HO-CDI as a component.
To gauge the impact of these programs, a team led by researchers from Harvard Medical School and Harvard Pilgrim Health Care Institute used data from the National Healthcare Safety Network (NHSN) on HO-CDI among hospitalized adults from January 2013 through March 2019, defining HO-CDI as any case identified from stool samples collected more than 3 days after admission. They then conducted an interrupted time series analysis to examine any association between the programs and quarterly HO-CDI rates at participating hospitals.
Among the more than 24 million patients at 265 hospitals that reported HO-CDIs to NHSN, there were 74,681 HO-CDI cases during the study period. The overall mean HO-CDI incidence across all hospital was 6.8 events per 100,000 patient-days. Most hospitals (55%) were medium-sized (100 to 399 beds), not-for-profit (77%), teaching hospitals (77%), and located in metropolitan areas (86%).
Regardless of the type of testing the hospitals used to identify CDI cases (nucleic acid amplification tests [NAATs], enzyme immunoassay [EIA] tests, or other tests), the analysis found that implementation of the two VBIPs was associated with a 6% decline in the HO-CDI incidence rate (adjusted incidence rate ratio [aIRR], 0.94; 95% confidence interval [CI], 0.89 to 0.99) in the immediate quarter after October 2016 and a 4% decline in slope per quarter (aIRR, 0.96; 95% CI, 0.95 to 0.97).
The results were similar in a sensitivity analysis that included a 1-year roll-in period to account for the lag between the inclusion of HO-CDI as a VBIP target and program implementation.
Antibiotic and diagnostic stewardship may play a role
The authors say the association between the incentive programs and the reduced HO-CDI incidence at US hospitals could be explained by greater adherence and commitment to the type of infection-prevention measures that can reduce C difficile transmission in hospitals, such as hand washing, contact precautions, and environmental screening and cleaning.
It could also be linked to improved antimicrobial stewardship practices, they suggest. Some hospital stewardship programs, for example, have introduced measures in recent years to cycle or restrict the use of antibiotics like fluoroquinolones, which are known to be associated with increased risk of C difficile.
Finally, improved diagnostic stewardship could be playing a role, the authors say, by reducing C difficile testing in patients who are on laxatives or who don't have other significant symptoms of C difficile infection. That could have resulted in fewer false-positives being reported to NHSN. Whatever the reason, they say the decline—which has been observed in studies by the CDC and others—is welcome.
"Regardless of the mechanism behind HO-CDI temporal decline, this change is likely to be accompanied by lower costs and less overtreatment and exposure to unnecessary antibiotics because of false-positive C. difficile test results," they wrote.
The authors say further research into the specific reasons for the decline could shape future interventions targeted by CMS incentive programs.
