Evaluating the Use of the Case Mix Index for Risk Adjustment of Healthcare-Associated Infection Data: An Illustration using Clostridium difficile Infection Data from the National Healthcare Safety Network

Nurse Work Environment and Hospital-Onset Clostridioides difficile Infection

BACKGROUND

Clostridioides difficile is the leading cause of hospital-onset diarrhea and is associated with increased lengths of stay and mortality. While some hospitals have successfully reduced the burden of C. difficile infection (CDI), many still struggle to reduce hospital-onset CDI. Nurses-because of their close proximity to patients-are an important resource in the prevention of hospital-onset CDI.

OBJECTIVE

Determine whether there is an association between the nurse work environment and hospital-onset CDI.

METHODS

Survey data of 2016 were available from 15,982 nurses employed in 353 acute care hospitals. These data, aggregated to the hospital level, provided measures of the nurse work environments. They were merged with 2016 hospital-onset CDI data from Hospital Compare, which provided our outcome measure-whether a hospital had a standardized infection ratio (SIR) above or below the national average SIR. Hospitals above the average SIR had more infections than predicted when compared to the national average.

RESULTS

In all, 188 hospitals (53%) had SIRs higher than the national average. The odds of hospitals having higher than average SIRs were significantly lower, with odds ratios ranging from 0.35 to 0.45, in hospitals in the highest quartile for all four nurse work environment subscales (managerial support, nurse participation in hospital governance, physician-nurse relations, and adequate staffing) than in hospitals in the lowest quartile.

CONCLUSIONS

Findings show an association between the work environment of nurses and hospital-onset CDI. A promising strategy to lower hospital-onset CDI and other infections is a serious and sustained commitment by hospital leaders to significantly improve nurse work environments.

Mitigating hospital-onset Clostridioides difficile: The impact of an optimized environmental hygiene program in eight hospitals

OBJECTIVE

To evaluate the impact of a standardized, process-validated intervention utilizing daily hospital-wide patient-zone sporicidal disinfectant cleaning on incidence density of healthcare-onset Clostridioides difficile infection (HO-CDI) standardized infection ratios (SIRs).

DESIGN

Multi-site, quasi-experimental study, with control hospitals and a nonequivalent dependent variable.

SETTING

The study was conducted across 8 acute-care hospitals in 6 states with stable endemic HO-CDI SIRs.

METHODS

Following an 18-month preintervention control period, each site implemented a program of daily hospital-wide sporicidal disinfectant patient zone cleaning. After a wash-in period, thoroughness of disinfection cleaning (TDC) was monitored prospectively and optimized with performance feedback utilizing a previously validated process improvement program. Mean HO-CDI SIRs were calculated by quarter for the pre- and postintervention periods for both the intervention and control hospitals. We used a difference-in-differences analysis to estimate the change in the average HO-CDI SIR and HO-CAUTI SIR for the pre- and postintervention periods.

RESULTS

Following the wash-in period, the TDC improved steadily for all sites and by 18 months was 93.6% for the group. The mean HO-CDI SIRs decreased from 1.03 to 0.6 (95% CI, 0.13-0.75; P = .009). In the adjusted difference-in-differences analysis in comparison to controls, there was a 0.55 reduction (95% CI, -0.77 to -0.32) in HO-CDI (P < .001) or a 50% relative decrease from baseline.

CONCLUSIONS

This study represents the first multiple-site, quasi-experimental study with control hospitals and a nonequivalent dependent variable to evaluate a 4-component intervention on HO-CDI. Following ongoing improvement in cleaning thoroughness, there was a sustained 50% decrease in HO-CDI SIRs compared to controls.

Declines in the utilization of hospital-based care during COVID-19 pandemic

The disruptions of the coronavirus disease 2019 (COVID-19) pandemic impacted the delivery and utilization of healthcare services with potential long-term implications for population health and the hospital workforce. Using electronic health record data from over 700 US acute care hospitals, we documented changes in admissions to hospital service areas (inpatient, observation, emergency room [ER], and same-day surgery) during 2019-2020 and examined whether surges of COVID-19 hospitalizations corresponded with increased inpatient disease severity and death rate. We found that in 2020, hospitalizations declined by 50% in April, with greatest declines occurring in same-day surgery (-73%). The youngest patients (0-17) experienced largest declines in ER, observation, and same-day surgery admissions; inpatient admissions declined the most among the oldest patients (65+). Infectious disease admissions increased by 52%. The monthly measures of inpatient case mix index, length of stay, and non-COVID death rate were higher in all months in 2020 compared with respective months in 2019.

Leapfrog Hospital Safety Score, Magnet Designation, and Healthcare-Associated Infections in United States Hospitals

OBJECTIVE

Healthcare-associated infections (HAIs) pose a challenge to patient safety. Although studies have explored individual level, few have focused on organizational factors such as a hospital's safety infrastructure (indicated by Leapfrog Hospital Safety Score) or workplace quality (Magnet recognition). The aim of the study was to determine whether Magnet and hospitals with better Leapfrog Hospital Safety Scores have fewer HAIs.

METHODS

Ordered probit regression analyses tested associations between Safety Score, Magnet status, and standardized infection ratios, depicting whether a hospital had a Clostridium difficile infection (CDI) and methicillin-resistant Staphylococcus aureus (MRSA) bloodstream infection standardized infection ratio that was "better," "no different," or "worse" than a National Benchmark as per Centers for Disease Control and Prevention's National Healthcare Safety Network definitions.

RESULTS

Accounting for confounders, relative to "A" hospitals, "B" and "C" hospitals had significant and negative relationships with CDI (-0.16, P < 0.01, and -0.14, P < 0.05, respectively) but not MRSA bacteremia. Magnet hospitals had a significant and positive relationship with MRSA bloodstream infections (0.74, P < 0.001) but a significant negative relationship with CDI (-0.21, P < 0.01) compared with non-Magnet.

CONCLUSIONS

A hospitals performed better on CDI but not MRSA bloodstream infections. In contrast, Magnet designation was associated with fewer than expected MRSA infections but more than expected CDIs. These mixed results indicate that hospital global assessments of safety and workplace quality differentially and imperfectly predict its level of HAIs, suggesting the need for more precise organizational measures of safety and more nuanced approaches to infection prevention and reduction.

Risk for Clostridioides difficile Infection Among Hospitalized Patients Associated With Multiple Healthcare Exposures Prior to Admission

BACKGROUND

Clostridioides difficile infection (CDI) is a common healthcare-associated infection and is often used as an indicator of hospital safety or quality. However, healthcare exposures occurring prior to hospitalization may increase risk for CDI. We conducted a case-control study comparing hospitalized patients with and without CDI to determine if healthcare exposures prior to hospitalization (ie, clinic visits, antibiotics, family members with CDI) were associated with increased risk for hospital-onset CDI, and how risk varied with time between exposure and hospitalization.

METHODS

Records were collected from a large insurance-claims database from 2001 to 2017 for hospitalized adult patients. Prior healthcare exposures were identified using inpatient, outpatient, emergency department, and prescription drug claims; results were compared between various CDI case definitions.

RESULTS

Hospitalized patients with CDI had significantly more frequent healthcare exposures prior to admission. Healthcare visits, antibiotic use, and family exposures were associated with greater likelihood of CDI during hospitalization. The degree of association diminished with time between exposure and hospitalization. Results were consistent across CDI case definitions.

CONCLUSIONS

Many different prior healthcare exposures appear to increase risk for CDI presenting during hospitalization. Moreover, patients with CDI typically have multiple exposures prior to admission, confounding the ability to attribute cases to a particular stay.

Reductions in positive Clostridioides difficile events reportable to National Healthcare Safety Network (NHSN) with adoption of reflex enzyme immunoassay (EIA) testing in 13 Atlanta hospitals

In total, 13 facilities changed C. difficile testing to reflexive testing by enzyme immunoassay (EIA) only after a positive nucleic acid-amplification test (NAAT); the standardized infection ratio (SIR) decreased by 46% (range, -12% to -71% per hospital). Changing testing practice greatly influenced a performance metric without changing C. difficile infection prevention practice.

Early prediction of diagnostic-related groups and estimation of hospital cost by processing clinical notes

As healthcare providers receive fixed amounts of reimbursement for given services under DRG (Diagnosis-Related Groups) payment, DRG codes are valuable for cost monitoring and resource allocation. However, coding is typically performed retrospectively post-discharge. We seek to predict DRGs and DRG-based case mix index (CMI) at early inpatient admission using routine clinical text to estimate hospital cost in an acute setting. We examined a deep learning-based natural language processing (NLP) model to automatically predict per-episode DRGs and corresponding cost-reflecting weights on two cohorts (paid under Medicare Severity (MS) DRG or All Patient Refined (APR) DRG), without human coding efforts. It achieved macro-averaged area under the receiver operating characteristic curve (AUC) scores of 0·871 (SD 0·011) on MS-DRG and 0·884 (0·003) on APR-DRG in fivefold cross-validation experiments on the first day of ICU admission. When extended to simulated patient populations to estimate average cost-reflecting weights, the model increased its accuracy over time and obtained absolute CMI error of 2·40 (1·07%) and 12·79% (2·31%), respectively on the first day. As the model could adapt to variations in admission time, cohort size, and requires no extra manual coding efforts, it shows potential to help estimating costs for active patients to support better operational decision-making in hospitals.

Use of a Victorian statewide surveillance program to evaluate the burden of healthcare-associated Staphylococcus aureus bacteraemia and Clostridioides difficile infection in patients with cancer

BACKGROUND

Patients with cancer are at high risk for infection, but the epidemiology of healthcare-associated Staphylococcus aureus bacteraemia (HA-SAB) and Clostridioides difficile infection (HA-CDI) in Australian cancer patients has not previously been reported.

AIMS

To compare the cumulative aggregate incidence and time trends of HA-SAB and HA-CDI in a predefined cancer cohort with a mixed statewide patient population in Victoria, Australia.

METHODS

All SAB and CDI events in patients admitted to Victorian healthcare facilities between 1^st July 2010 and 31^st December 2018 were submitted to the Victorian Healthcare Associated Infection Surveillance System Coordinating Centre. Descriptive analyses and multilevel mixed-effects Poisson regression modelling were applied to a standardised data extract.

RESULTS

In total, 10,608 and 13,118 SAB and CDI events were reported across 139 Victorian healthcare facilities, respectively. Of these, 89 (85%) and 279 (88%) were healthcare-associated in the cancer cohort compared to 34% (3,561/10,503) and 66% (8,403/12,802) in the statewide cohort. The aggregate incidence was more than two-fold higher in the cancer compared to the statewide cohort for HA-SAB (2.25 [95% CI: 1.74-2.77] vs. 1.11 [95% CI: 1.07-1.15] HA-SABs/10,000 OBDs) and three-fold higher for HA-CDI (6.26 [95% CI: 5.12-7.41] vs. 2.31 [95% CI: 2.21-2.42] HA-CDIs/10,000 OBDs). Higher quarterly diminishing rates were observed in the cancer cohort than the statewide data for both infections.

CONCLUSIONS

Our findings demonstrate a higher burden of HA-SAB and HA-CDI in a cancer cohort when compared with state data and highlight the need for cancer-specific targets and benchmarks to meaningfully support quality improvement. This article is protected by copyright. All rights reserved.

Association Between Antibiotic Use and Hospital-onset Clostridioides difficile Infection in US Acute Care Hospitals, 2006-2012: An Ecologic Analysis

BACKGROUND

Unnecessary antibiotic use (AU) contributes to increased rates of Clostridioides difficile infection (CDI). The impact of antibiotic restriction on hospital-onset CDI (HO-CDI) has not been assessed in a large group of US acute care hospitals (ACHs).

METHODS

We examined cross-sectional and temporal associations between rates of hospital-level AU and HO-CDI using data from 549 ACHs. HO-CDI was defined as a discharge with a secondary International Classification of Diseases, Ninth Revision, Clinical Modification code for CDI (008.45), and treatment with metronidazole or oral vancomycin > 3 days after admission. Analyses were performed using multivariable generalized estimating equation models adjusting for patient and hospital characteristics.

RESULTS

During 2006-2012, the unadjusted annual rates of HO-CDI and total AU were 7.3 per 10 000 patient-days (PD) (95% confidence interval [CI], 7.1-7.5) and 811 days of therapy (DOT)/1000 PD (95% CI, 803-820), respectively. In the cross-sectional analysis, for every 50 DOT/1000 PD increase in total AU, there was a 4.4% increase in HO-CDI. For every 10 DOT/1000 PD increase in use of third- and fourth-generation cephalosporins or carbapenems, there was a 2.1% and 2.9% increase in HO-CDI, respectively. In the time-series analysis, the 6 ACHs with a ≥30% decrease in total AU had a 33% decrease in HO-CDI (rate ratio, 0.67 [95% CI, .47-.96]); ACHs with a ≥20% decrease in fluoroquinolone or third- and fourth-generation cephalosporin use had a corresponding decrease in HO-CDI of 8% and 13%, respectively.

CONCLUSIONS

At an ecologic level, reductions in total AU, use of fluoroquinolones, and use of third- and fourth-generation cephalosporins were each associated with decreased HO-CDI rates.

Modest Clostridiodes difficile infection prediction using machine learning models in a tertiary care hospital

Previous studies have shown promising results of machine learning (ML) models for predicting health outcomes. We develop and test ML models for predicting Clostridioides difficile infection (CDI) in hospitalized patients. This is a retrospective cohort study conducted during 2015-2017. All inpatients tested for C. difficile were included. CDI was defined as having a positive glutamate dehydrogenase and toxin results. We restricted analyses to the first record of C. difficile testing per patient. Of 3514 patients tested, 136 (4%) had CDI. Age and antibiotic use within 90 days before C. difficile testing were associated with CDI (P < 0.01). We tested 10 ML methods with and without resampling. Logistic regression, random forest and naïve Bayes models yielded the highest AUC ROC performance: 0.6. Predicting CDI was difficult in our cohort of patients tested for CDI. Multiple ML models yielded only modest results in a real-world population of hospitalized patients tested for CDI.

Evaluation of the National Healthcare Safety Network standardized infection ratio risk adjustment for healthcare-facility-onset Clostridioides difficile infection in intensive care, oncology, and hematopoietic cell transplant units in general acute-care hospitals

OBJECTIVE

To evaluate the National Health Safety Network (NHSN) hospital-onset Clostridioides difficile infection (HO-CDI) standardized infection ratio (SIR) risk adjustment for general acute-care hospitals with large numbers of intensive care unit (ICU), oncology unit, and hematopoietic cell transplant (HCT) patients.

DESIGN

Retrospective cohort study.

SETTING

Eight tertiary-care referral general hospitals in California.

METHODS

We used FY 2016 data and the published 2015 rebaseline NHSN HO-CDI SIR. We compared facility-wide inpatient HO-CDI events and SIRs, with and without ICU data, oncology and/or HCT unit data, and ICU bed adjustment.

RESULTS

For these hospitals, the median unmodified HO-CDI SIR was 1.24 (interquartile range [IQR], 1.15-1.34); 7 hospitals qualified for the highest ICU bed adjustment; 1 hospital received the second highest ICU bed adjustment; and all had oncology-HCT units with no additional adjustment per the NHSN. Removal of ICU data and the ICU bed adjustment decreased HO-CDI events (median, -25%; IQR, -20% to -29%) but increased the SIR at all hospitals (median, 104%; IQR, 90%-105%). Removal of oncology-HCT unit data decreased HO-CDI events (median, -15%; IQR, -14% to -21%) and decreased the SIR at all hospitals (median, -8%; IQR, -4% to -11%).

CONCLUSIONS

For tertiary-care referral hospitals with specialized ICUs and a large number of ICU beds, the ICU bed adjustor functions as a global adjustment in the SIR calculation, accounting for the increased complexity of patients in ICUs and non-ICUs at these facilities. However, the SIR decrease with removal of oncology and HCT unit data, even with the ICU bed adjustment, suggests that an additional adjustment should be considered for oncology and HCT units within general hospitals, perhaps similar to what is done for ICU beds in the current SIR.

Incidence and Outcomes Associated With Clostridium difficile Infections: A Systematic Review and Meta-analysis

IMPORTANCE

An understanding of the incidence and outcomes of Clostridium difficile infection (CDI) in the United States can inform investments in prevention and treatment interventions.

OBJECTIVE

To quantify the incidence of CDI and its associated hospital length of stay (LOS) in the United States using a systematic literature review and meta-analysis.

DATA SOURCES

MEDLINE via Ovid, Cochrane Library Databases via Wiley, Cumulative Index of Nursing and Allied Health Complete via EBSCO Information Services, Scopus, and Web of Science were searched for studies published in the United States between 2000 and 2019 that evaluated CDI and its associated LOS.

STUDY SELECTION

Incidence data were collected only from multicenter studies that had at least 5 sites. The LOS studies were included only if they assessed postinfection LOS or used methods accounting for time to infection using a multistate model or compared propensity score-matched patients with CDI with control patients without CDI. Long-term-care facility studies were excluded. Of the 119 full-text articles, 86 studies (72.3%) met the selection criteria.

DATA EXTRACTION AND SYNTHESIS

Two independent reviewers performed the data abstraction and quality assessment. Incidence data were pooled only when the denominators used the same units (eg, patient-days). These data were pooled by summing the number of hospital-onset CDI incident cases and the denominators across studies. Random-effects models were used to obtain pooled mean differences. Heterogeneity was assessed using the I2 value. Data analysis was performed in February 2019.

MAIN OUTCOMES AND MEASURES

Incidence of CDI and CDI-associated hospital LOS in the United States.

RESULTS

When the 13 studies that evaluated incidence data in patient-days due to hospital-onset CDI were pooled, the CDI incidence rate was 8.3 cases per 10 000 patient-days. Among propensity score-matched studies (16 of 20 studies), the CDI-associated mean difference in LOS (in days) between patients with and without CDI varied from 3.0 days (95% CI, 1.44-4.63 days) to 21.6 days (95% CI, 19.29-23.90 days).

CONCLUSIONS AND RELEVANCE

Pooled estimates from currently available literature suggest that CDI is associated with a large burden on the health care system. However, these estimates should be interpreted with caution because higher-quality studies should be completed to guide future evaluations of CDI prevention and treatment interventions.

Community-acquired and hospital-acquired medication harm among older inpatients and impact of a state-wide medication management intervention

Background

We previously reported reduction in the rate of hospitalisations with medication harm among older adults with our ‘Pharm2Pharm’ intervention, a pharmacist-led care transition and care coordination model focused on best practices in medication management. The objectives of the current study are to determine the extent to which medication harm among older inpatients is ‘community acquired’ versus ‘hospital acquired’ and to assess the effectiveness of the Pharm2Pharm model with each type.

Methods

After a 3-year baseline, six non-federal general acute care hospitals with 50 or more beds in Hawaii implemented Pharm2Pharm sequentially. The other five such hospitals served as the comparison group. We measured frequencies and quarterly rates of admissions among those aged 65 and older with ‘community-acquired’ (International Classification of Diseases-coded as present on admission) and ‘hospital-acquired’ (coded as not present on admission) medication harm per 1000 admissions from 2010 to 2014.

Results

There were 189 078 total admissions from 2010 through 2014, 7% of which had one or more medication harm codes. There were 16 225 medication harm codes, 70% of which were community-acquired, among these 13 795 admissions. The varied times when the intervention was implemented across hospitals were associated with a significant reduction in the rate of admissions with community-acquired medication harm compared with non-intervention hospitals (p=0.001), and specifically harm by anticoagulants (p<0.0001) and by medications in therapeutic use (p<0.001). The hospital-acquired medication harm rate did not change. The rate of admissions with community-acquired medication harm was reduced by 4.28 admissions per 1000 admissions per quarter in the Pharm2Pharm hospitals relative to the comparison hospitals.

Conclusion

The Pharm2Pharm model is an effective way to address the growing problem of community-acquired medication harm among high-risk, chronically ill patients. This model demonstrates the importance of deploying specially trained pharmacists in the hospital and in the community to systematically identify and resolve drug therapy problems.

Understanding physician antibiotic prescribing behavior for children with enterovirus infection

Background

Our previous study demonstrated that pediatricians prescribe antibiotics without proper clinical justification to patients with enterovirus infection, although antibiotics are not effective in treating the infections caused by these viruses. To improve the quality of healthcare, we aim to evaluate the association of clinical and demographic characteristics of patients and further to identify the determining factors for prescribing antibiotics to children experiencing enterovirus infection.

Methods

We retrospectively reviewed the medical records of children who were hospitalized between January 2008 and December 2016 with a diagnosis of herpangina or hand-foot-mouth disease (HFMD). We identified those children who were prescribed antibiotics for at least 24 hours during admission. We conducted a retrospective descriptive study to analyze data in order to determine the factors associated with pediatrician antibiotics prescribing for enterovirus infection.

Results

In the nine years of study period, the rate of antibiotics use was about 13% in these patients. A total of 3659 patients were enrolled during 2008~2012 and analyzed in detail. Elevated levels of C-reactive protein (CRP) and presence of leukocytosis in blood (WBC) were both significantly associated with pediatrician antibiotic prescribing for enterovirus infection (p<0.001). Between different specialistic devisions, there was significantly different proportion of antibiotics utilization for patients. In further analysis of antibiotics prescribing by Receiver operating characteristic (ROC) curve method, the level of CRP significantly had more the area under curve (0.708) compared with the count of WBC (p<0.05).

Conclusions

The present study indicates that higher serum level of CRP is strongly associated with pediatricians prescribing antibiotics for children experiencing herpangina or HFMD. Antibiotic prescribing is a complex process. Pediatricians should be more judicious in decision-making time by their specialistics. Our findings would shed new light on process and allay the concern about inappropriate antibiotics.

Increasing Health Care Burden of Chronic Liver Disease Compared With Other Chronic Diseases, 2004-2013

BACKGROUND & AIMS

Chronic liver disease (CLD) is a common and expensive condition, and studies of CLD-related hospitalizations have underestimated the true burden of disease. We analyzed data from a large, diverse health care system to compare time trends in CLD-related hospitalizations with those in congestive heart failure (CHF) or chronic obstructive pulmonary disease (COPD).

METHODS

We collected data from a large health care system in Texas on hospitalizations related to CLD (n = 27,783), CHF (n = 60,415), and COPD (n = 34,199) from January 1, 2004 through December 31, 2013. We calculated annual hospitalization rates (per 100,000) and compared hospital course, inpatient mortality, ancillary services, and readmissions.

RESULTS

Compared with patients with CHF (median age, 71 years) or COPD (median age, 69 years), patients with CLD were significantly younger (median age, 57 years) (P < .01 vs CHF and COPD). Higher proportions of patients with CLD were uninsured (11.7% vs 5.4% for CHF and 5.4% for COPD, P < .01) and Hispanic (17% for CLD vs 9.3% for CHF and 5.0% for COPD, P < .01). A lower proportion of patients with CLD had Medicare (41.5% vs 68.6% with CHF and 70.1% with COPD, P < .01). From 2004 through 2013, the rate of CLD-related hospitalization increased by 92% (from 1295/100,000 to 2490/100,000), compared with 6.7% for CHF (from 3843/100,000 to 4103/100,000) and 48.8% for COPD (from 1775/100,000 to 2642/100,000). During this time period, CLD-related hospitalizations covered by Medicare increased from 31.8% to 41.5%, whereas hospitalizations covered by Medicare did not change for CHF (remained at 70%) or COPD (remained at 70%). Patients with CLD had longer hospital stays (7.3 days vs 6.2 days for CHF and 5.9 days for COPD, P < .01). A higher proportion of patients with CLD died or were discharged to hospice (14.2% vs 11.5% of patients with CHF and 9.3% of patients with COPD, P < .01), and a smaller proportion had access to postacute care (13.2% vs 23.2% of patients with CHF and 27.4% of patients with COPD, P < .01). A higher proportion of patients with CLD were readmitted to the hospital within 30 days (25% vs 21.9% of patients with CHF and 20.6% with COPD, P < .01).

CONCLUSIONS

Patients with CLD, compared with selected other chronic diseases, had increasing rates of hospitalization, longer hospital stays, more readmissions, and, despite these adverse outcomes, less access to postacute care. Disease management models for CLD are greatly needed to manage the anticipated increase in hospitalizations for CLD.

Clinical Practice Guidelines for Clostridium difficile Infection in Adults and Children: 2017 Update by the Infectious Diseases Society of America (IDSA) and Society for Healthcare Epidemiology of America (SHEA)

A panel of experts was convened by the Infectious Diseases Society of America (IDSA) and Society for Healthcare Epidemiology of America (SHEA) to update the 2010 clinical practice guideline on Clostridium difficile infection (CDI) in adults. The update, which has incorporated recommendations for children (following the adult recommendations for epidemiology, diagnosis, and treatment), includes significant changes in the management of this infection and reflects the evolving controversy over best methods for diagnosis. Clostridium difficile remains the most important cause of healthcare-associated diarrhea and has become the most commonly identified cause of healthcare-associated infection in adults in the United States. Moreover, C. difficile has established itself as an important community pathogen. Although the prevalence of the epidemic and virulent ribotype 027 strain has declined markedly along with overall CDI rates in parts of Europe, it remains one of the most commonly identified strains in the United States where it causes a sizable minority of CDIs, especially healthcare-associated CDIs. This guideline updates recommendations regarding epidemiology, diagnosis, treatment, infection prevention, and environmental management.

Electronically Available Comorbid Conditions for Risk Prediction of Healthcare-Associated Clostridium difficile Infection

OBJECTIVE To analyze whether electronically available comorbid conditions are risk factors for Centers for Disease Control and Prevention (CDC)-defined, hospital-onset Clostridium difficile infection (CDI) after controlling for antibiotic and gastric acid suppression therapy use. PATIENTS Patients aged ≥18 years admitted to the University of Maryland Medical Center between November 7, 2015, and May 31, 2017. METHODS Comorbid conditions were assessed using the Elixhauser comorbidity index. The Elixhauser comorbidity index and the comorbid condition components were calculated using the International Classification of Disease, Tenth Revision, Clinical Modification (ICD-10-CM) codes extracted from electronic medical records. Bivariate associations between CDI and potential covariates for multivariable regression, including antibiotic use, gastric acid suppression therapy use, as well as comorbid conditions, were estimated using log binomial multivariable regression. RESULTS After controlling for antibiotic use, age, proton-pump inhibitor use, and histamine-blocker use, the Elixhauser comorbidity index was a significant risk factor for predicting CDI. There was an increased risk of 1.26 (95% CI, 1.19-1.32) of having CDI for each additional Elixhauser point added to the total Elixhauser score. CONCLUSIONS An increase in Elixhauser score is associated with CDI. Our study and other studies have shown that comorbid conditions are important risk factors for CDI. Electronically available comorbid conditions and scores like the Elixhauser index should be considered for risk-adjustment of CDC CDI rates. Infect Control Hosp Epidemiol 2018;39:297-301.

Associations between antimicrobial stewardship program elements and Clostridium difficile infection performance

Hospitals are categorized as better, no different, or worse at a national level based on their Clostridium difficile infection performance. Institutional antimicrobial stewardship programs seek to decrease the occurrence of C difficile by implementing strategies to address antibiotic usage; however, optimal structure and strategies for accomplishing this remain largely unknown. We found that a higher proportion of hospitals with either a worse or no different rank used a postprescription audit and feedback strategy than hospitals with a better rank.

Association Between High-Risk Medication Usage and Healthcare Facility-Onset C. difficile Infection

OBJECTIVE

National hospital performance measures for C. difficile infection (CD) are available; comparing antibacterial use among performance levels can aid in identifying effective antimicrobial stewardship strategies to reduce CDI rates.

DESIGN

Hospital-level, cross-sectional analysis.

METHODS

Hospital characteristics (ie, demographics, medications, patient mix) were obtained for 77 hospitals for 2013. Hospitals were assigned 1 of 3 levels of a CDI standardized infection ratio (SIR): ‘Worse than,’ ‘Better than,’ or ‘No different than’ a national benchmark. Analyses compared medication use (total and broad-spectrum antibacterials) for 3 metrics: days of therapy per 1,000 patient days; length of therapy; and proportion of patients receiving a medication across SIR levels. A multivariate, ordered-probit regression identified characteristics associated with SIR categories.

RESULTS

Regarding total average antimicrobial use per patient, there was a significant difference detected in mean length of therapy: ‘No different’ hospitals having the longest (4.93 days) versus ‘Worse’ (4.78 days) and ‘Better’ (4.43 days) (P<.01). ‘Better’ hospitals used fewer total antibacterials (693 days of therapy per 1,000 patient days) versus ‘No different’ (776 days) versus ‘Worse’ (777 days) (P<.05). The ‘Better’ hospitals used broad-spectrum antibacterials for a shorter average length of therapy (4.03 days) versus ‘No different’ (4.51 days) versus ‘Worse’ (4.38 days) (P<.05). ‘Better’ hospitals used fewer broad-spectrum antibacterials (310 days of therapy per 1,000 patient days) versus ‘No different’ (364 days) versus ‘Worse’ (349 days) (P<.05). Multivariate analysis revealed that the proportion of elderly patients and chemotherapy days of therapy per 1,000 patient days was significantly negatively associated with the SIR.

CONCLUSIONS

These findings have potential implications regarding the need to fully account for hospital patient mix when carrying out inter-hospital comparisons of CDI rates.

Infect Control Hosp Epidemiol 2016;37:909–915