Antibiotic Use in Non–University Regional Acute Care General Hospitals in Southwestern Germany, 2001–2002

Evaluation of the impact before and after the application of an antimicrobial stewardship program at Dong Thap General Hospital, Vietnam, from 2017 to 2021

Background

Vietnam has one of the highest rates of antibiotic resistance in Asia. In 2020, the Vietnam Minister of Health introduced new legislation for the implementation of an antimicrobial stewardship program (ASP). The evidence for the effectiveness of ASP in small hospitals and hospitals located in provinces was limited compared with larger-scale and central city hospitals.

Aim

Evaluation of the impact before and after the introduction of an antimicrobial stewardship program at Dong Thap General Hospital, from 2017 to 2021.

Methods

Retrospective data was collected from June 2017 to June 2021. The impact of the ASP on changes in antibiotic use and the clinical outcome associated with the implementation of the ASP was evaluated using autoregressive integrated moving average modelling of controlled interrupted time-series analysis.

Results

There was a significant and sustained decrease in antibiotic consumption level (step change) in 2 indicators, DOT/1000PD (129.55; P<0.01) and LOT/1000PD (99.95, P<0.01), immediately after the ASP intervention. There were no statistically significant changes identified in terms of consumption with DDD/1000PD, or in the clinical outcomes. The results showed no statistically significant change in consumption trend (ramps) in all evaluated indicators. No statistically significant changes in consumption levels and trends were observed in the control group.

Conclusion

The ASP implemented in Dong Thap General Hospital from 2017 to 2021 showed a considerable influence on antibiotic consumption as indicated by the DOT/1000 PD and LOT/1000 PD during the initial stages. Moreover, controlling antibiotic consumption did not negatively impact patient outcomes.

Consumption of anti-meticillin-resistant Staphylococcus aureus antibiotics in Swiss hospitals is associated with antibiotic stewardship measures

BACKGROUND

Consumption of antibiotics active against meticillin-resistant Staphylococcus aureus (MRSA) has been described in numerous European studies. However, the underlying predictors of consumption are still poorly understood.

AIM

To describe the consumption of anti-MRSA antibiotics (daptomycin, intravenous glycopeptides, linezolid) in Switzerland over time and to identify underlying predictor variables.

METHODS

A retrospective observational multi-centre study was conducted in 21 Swiss hospitals over a period of 11 years (2009-2019). Multiple linear regression models were built to identify regional and hospital-specific predictor variables affecting the consumption of anti-MRSA antibiotics.

FINDINGS

Consumption of anti-MRSA antibiotics increased between 2009 and 2019 from 12.7 to 24.5 defined daily doses per 1000 bed-days (+93%). In the first model presented, which includes data of the whole study period, the following variables were associated with higher anti-MRSA antibiotic consumption: number of MRSA cases (P < 0.01), year (P < 0.01), hospital type (tertiary care university hospitals vs others, P < 0.01), hospital department (intensive care unit vs others, P < 0.01) and linguistic region (French vs German and German vs Italian, P < 0.01). In a second model including data from a query on hospital policies in place in 2019, the presence of an antibiotic stewardship group (P < 0.01) and prescription restrictions (P < 0.01) were associated with consumption of anti-MRSA antibiotics.

CONCLUSION

Our study shows that both the presence of an antibiotic stewardship group and the implementation of prescription restrictions, i.e. factors that can be controlled by the hospital itself, were associated with a lower consumption of anti-MRSA antibiotics.

Comparison of the defined daily dose and days of treatment methods for evaluating the consumption of antibiotics and antifungals in the intensive care unit

OBJECTIVE

To compare the measurement of antimicrobial consumption by defined daily dose (DDD) versus by days of therapy (DOT).

DESIGN

Retrospective analysis of clinical and administrative data from patients admitted to a polyvalent ICU.

SETTING

ICU at a University Hospital in Spain.

PATIENTS

All patients admitted to the ICU.

INTERVENTIONS

None.

MAIN VARIABLES OF INTEREST

For the DDD method, the World Health Organization (WHO)-assigned DDD was determined for the all the prescribed antimicrobials. For the DOT method, one DOT represented the administration of a single agent on a given day regardless of the number of doses administered. To express aggregate use, total DDDs and total DOTs were normalized to 100 patient-days.

RESULTS

During the study period, 2393 adult patients were admitted to the ICU. Total median antimicrobial drugs measured by DDDs was 535.3 (IQR 319.8-845.5) vs. 344.0 (IQR 117.2-544.5) when measured by DOTs, p<0.001. When antimicrobial consumption was normalized to 100 patient-days, median antimicrobial consumption was also higher when measured by DDDs [2.98/100 patient-days (IQR 1.76-5.25) vs. 1.89/100 patient-days (IQR 0.64-3.0) when measured by DOTs, p<0.001].

CONCLUSIONS

For most antibacterial and antifungal drugs used in critically ill patients, estimates of aggregate antibiotic use by DDDs per 100 patient-days and DOTs per 100 patient-days are discordant because the administered dose is dissimilar from the WHO-assigned DDD. DOT methods should be recommended to avoid the overestimation that occurs with DDDs in adult critically ill patients.

How to measure quantitative antibiotic use in order to support antimicrobial stewardship in acute care hospitals: a retrospective observational study

A cornerstone of antimicrobial stewardship programs (ASPs) is monitoring quantitative antibiotic use. Frequently used metrics are defined daily dose (DDD) and days of therapy (DOT). The purpose of this study was (1) to explore for the hospital setting the possibilities of quantitative data retrieval on the level of medical specialty and (2) to describe factors affecting the usability and interpretation of these quantitative metrics. We performed a retrospective observational study, measuring overall systemic antibiotic use at specialty level over a 1-year period, from December 1st 2014 to December 1st 2015, in one university and 13 non-university hospitals in the Netherlands. We distinguished surgical and non-surgical adult specialties. The association between DDDs, calculated from aggregated dispensing data, and DOTs, calculated from patient-level prescription data, was explored descriptively and related to organizational factors, data sources (prescription versus dispensing data), data registration, and data extraction. Twelve hospitals were able to extract dispensing data (DDD), three of which on the level of medical specialty; 13 hospitals were able to extract prescription data (DOT), 11 of which by medical specialty. A large variation in quantitative antibiotic use was found between hospitals and the correlation between DDDs and DOTs at specialty level was low. Differences between hospitals related to organizational factors, data sources, data registration, and data extraction procedures likely contributed to the variation in quantitative use and the low correlation between DDDs and DOTs. The differences in healthcare organization, data sources, data registration, and data extraction procedures contributed to the variation in reported quantitative use between hospitals. Uniform registration and extraction procedures are necessary for appropriate measurement and interpretation and benchmarking of quantitative antibiotic use.

Variability in antibiotic use across Ontario acute care hospitals

BACKGROUND

Antibiotic stewardship is a required organizational practice for Canadian acute care hospitals, yet data are scarce regarding the quantity and composition of antibiotic use across facilities. We sought to examine the variability, and risk-adjusted variability, in antibiotic use across acute care hospitals in Ontario, Canada's most populous province.

METHODS

Antibiotic purchasing data from IMS Health, previously demonstrated to correlate strongly with internal antibiotic dispensing data, were acquired for 129 Ontario hospitals from January to December 2014 and linked to patient day (PD) denominator data from administrative datasets. Hospital variation in DDDs/1000 PDs was determined for overall antibiotic use, class-specific use and six practices of clinical or ecological significance. Multivariable risk adjustment for hospital and patient characteristics was used to compare observed versus expected utilization.

RESULTS

There was 7.4-fold variability in the quantity of antibiotic use across the 129 acute care hospitals, from 253 to 1873 DDDs/1000 PDs. Variation was evident within hospital subtypes, exceeded that explained by hospital and patient characteristics, and included wide variability in proportion of broad-spectrum antibiotics (IQR 36%-48%), proportion of fluoroquinolones among respiratory antibiotics (IQR 40%-62%), proportion of ciprofloxacin among urinary anti-infectives (IQR 44%-60%), proportion of antibiotics with highest risk for Clostridium difficile (IQR 29%-40%), proportion of 'reserved-use' antibiotics (IQR 0.8%-3.5%) and proportion of anti-pseudomonal antibiotics among antibiotics with Gram-negative coverage (IQR 26%-40%).

CONCLUSIONS

There is extensive variability in antibiotic use, and risk-adjusted use, across acute care hospitals. This could motivate, focus and benchmark antibiotic stewardship efforts.

Guidance on the Selection of Appropriate Indicators for Quantification of Antimicrobial Usage in Humans and Animals

An increasing variety of indicators of antimicrobial usage has become available in human and veterinary medicine, with no consensus on the most appropriate indicators to be used. The objective of this review is therefore to provide guidance on the selection of indicators, intended for those aiming to quantify antimicrobial usage based on sales, deliveries or reimbursement data. Depending on the study objective, different requirements apply to antimicrobial usage quantification in terms of resolution, comprehensiveness, stability over time, ability to assess exposure and comparability. If the aim is to monitor antimicrobial usage trends, it is crucial to use a robust quantification system that allows stability over time in terms of required data and provided output; to compare usage between different species or countries, comparability must be ensured between the different populations. If data are used for benchmarking, the system comprehensiveness is particularly crucial, while data collected to study the association between usage and resistance should express the exposure level and duration as a measurement of the exerted selection pressure. Antimicrobial usage is generally described as the number of technical units consumed normalized by the population at risk of being treated in a defined period. The technical units vary from number of packages to number of individuals treated daily by adding different levels of complexity such as daily dose or weight at treatment. These technical units are then related to a description of the population at risk, based either on biomass or number of individuals. Conventions and assumptions are needed for all of these calculation steps. However, there is a clear lack of standardization, resulting in poor transparency and comparability. By combining study requirements with available approaches to quantify antimicrobial usage, we provide suggestions on the most appropriate indicators and data sources to be used for a given study objective.

Systematic review of antibiotic consumption in acute care hospitals

Antibiotic consumption is an easily quantifiable performance measure in hospitals and might be used for monitoring. We conducted a review of published studies and online surveillance reports reporting on antibiotic consumption in acute care hospitals between the years 1997 and 2013. A pooled estimate of antibiotic consumption was calculated using a random effects meta-analysis of rates with 95% confidence intervals. Heterogeneity was assessed through subgroup analysis and metaregression. Eighty studies, comprising data from 3130 hospitals, met the inclusion criteria. The pooled rate of hospital-wide consumption was 586 (95% confidence interval 540 to 632) defined daily doses (DDD)/1000 hospital days (HD) for all antibacterials. However, consumption rates were highly heterogeneous. Antibacterial consumption was highest in intensive care units, at 1563 DDD/1000 HD (95% confidence interval 1472 to 1653). Hospital-wide antibacterial consumption was higher in Western Europe and in medium-sized, private and university-affiliated hospitals. The methods of data collection were significantly associated with consumption rates, including data sources, dispensing vs. purchase vs. usage data, counting admission and discharge days and inclusion of low-consumption departments. Heterogeneity remained in all subgroup analyses. Major heterogeneity currently precludes defining acceptable antibiotic consumption ranges in acute care hospitals. Guidelines on antibiotic consumption reporting that will account for case mix and a minimal set of hospital characteristics recommending standardized methods for monitoring and reporting are needed.

Predicting Antimicrobial Resistance Prevalence and Incidence from Indicators of Antimicrobial Use: What Is the Most Accurate Indicator for Surveillance in Intensive Care Units?

OBJECTIVE

The optimal way to measure antimicrobial use in hospital populations, as a complement to surveillance of resistance is still unclear. Using respiratory isolates and antimicrobial prescriptions of nine intensive care units (ICUs), this study aimed to identify the indicator of antimicrobial use that predicted prevalence and incidence rates of resistance with the best accuracy.

METHODS

Retrospective cohort study including all patients admitted to three neonatal (NICU), two pediatric (PICU) and four adult ICUs between April 2006 and March 2010. Ten different resistance/antimicrobial use combinations were studied. After adjustment for ICU type, indicators of antimicrobial use were successively tested in regression models, to predict resistance prevalence and incidence rates, per 4-week time period, per ICU. Binomial regression and Poisson regression were used to model prevalence and incidence rates, respectively. Multiplicative and additive models were tested, as well as no time lag and a one 4-week-period time lag. For each model, the mean absolute error (MAE) in prediction of resistance was computed. The most accurate indicator was compared to other indicators using t-tests.

RESULTS

Results for all indicators were equivalent, except for 1/20 scenarios studied. In this scenario, where prevalence of carbapenem-resistant Pseudomonas sp. was predicted with carbapenem use, recommended daily doses per 100 admissions were less accurate than courses per 100 patient-days (p = 0.0006).

CONCLUSIONS

A single best indicator to predict antimicrobial resistance might not exist. Feasibility considerations such as ease of computation or potential external comparisons could be decisive in the choice of an indicator for surveillance of healthcare antimicrobial use.

Inpatient antibiotic consumption in a regional secondary hospital in New Zealand

BACKGROUND

Reporting of antibiotic consumption in hospitals is a crucial component of antibiotic stewardship, but data from Australasian secondary hospitals are scarce. The hypothesis of this audit is that antibiotic consumption in secondary hospitals would be lower than in tertiary centres.

AIMS

The study aims to present the first published audit of antibiotic consumption from a secondary hospital in New Zealand compared with two tertiary centres.

METHODS

Hospital population-level data were retrospectively accessed to identify all systemic antibiotics dispensed to adult inpatients at Taranaki District Health Board during 2011. Consumption was calculated in defined daily doses per 100 inpatient-days and per 100 admissions, stratified by drug class. Comparison was against published data from two tertiary centres.

RESULTS

Total consumption was lower, but that of high-risk antibiotic classes was higher than both tertiary centres. The relative consumption of lincosamides was 4.0 and 2.6 times higher than the two tertiary centres, with an associated 14% incidence of Clostridium difficile associated diarrhoea within 3 months.

CONCLUSION

Our secondary hospital appears to consume the wrong types of antibiotic rather than too much. Data from all Australasian hospitals, stratified by clinical service area and hospital level, are required for clinically relevant benchmarking.

WHO defined daily doses versus hospital-adjusted defined daily doses: impact on results of antibiotic use surveillance

OBJECTIVES

To investigate effects on surveillance results of hospital antibiotic use when WHO defined daily doses (WHO DDDs) are adjusted to doses recommended for hospitalized patients [hospital-adjusted defined daily doses (haDDDs)].

METHODS

Data for antibiotic use in 2006-11 for all 22 Norwegian Health Enterprises were analysed with both WHO DDDs and haDDDs as numerators. The haDDDs were determined from recommendations given in regional and national guidelines on antibiotic use in hospitals. The two ways of calculating the amount of antibiotic use were compared, with either the number of bed days (BDs) or the number of discharges as the denominator. The drug utilization 90% methodology was applied for ranking the use of the various antibiotics.

RESULTS

DDD adjustments altered the figures for total antibiotic use from 67.1 WHO DDDs/100 BDs to 49.3 haDDDs/100 BDs (-26.4%). The most marked difference was found for penicillins: 31.1 WHO DDDs/100 BDs versus 13.4 haDDDs/100 BDs (-56.8%). The corresponding figures for broad-spectrum antibiotics were 17.3 and 15.5 (-10.4%), respectively; for these antibiotics, the conversion changes varied significantly between institutions, from -16.7% to -3.3%. Ranking antibiotic use based on haDDDs resulted in higher positions for metronidazole, cefuroxime, cefotaxime and cefalotin/cefalexin compared with the WHO DDD-based ranking, where the penicillins dominated.

CONCLUSIONS

The low-set WHO DDDs for penicillins caused skewed surveillance results that concealed the real magnitude of broad-spectrum antibiotic use and distorted interhospital comparisons. For surveillance of antibiotic use in hospitals, WHO DDDs should be supplemented with haDDDs.

Variations and determinants of antibiotic consumption in Hungarian adult intensive care units

PURPOSE

The aim of this work was to study the use of systemic antibacterials and its possible determinants in Hungarian intensive care units (ICUs).

METHODS

Hospital pharmacy. departments provided package level dispensing data for their corresponding ICU (2006). Data were converted into defined daily doses (DDDs) and expressed as DDD per 100 patient-days and DDD per 100 admissions. Antibiotics were ranked by volume of DDDs, and the agents responsible for 90% of total use (DU90%) were noted. To explore differences and relationships between antibiotic use and antibiotic policy elements/ICU characteristics, the analysis of variances or the Pearson correlation analysis was performed.

RESULTS

Valid data were obtained for 44 ICUs. Antibiotic use varied widely (from 27.9 to 167.8 DDD per 100 patient-days and from 104.7 to 1784.6 DDD per 100 admissions). In total, 11-34 different antibacterials per ICUs were used, of which, 5-15 were in the DU90% segment. The proportional use of parenteral agents ranged from 46.2 to 98.3%. The mean of overall antibiotic use was highest for penicillins with beta-lactamase inhibitors, followed by quinolones and third-generation cephalosporins. Of the studied factors, only the ICU category (i.e., level of care) showed significant association with total antibacterial use.

CONCLUSIONS

The striking differences in total antibiotic use and the extensive use of the oral agents in some ICUs may indicate room for improvement. As none of the antibiotic policy elements were accompanied by lower antibiotic use in the pooled analysis, it suggests that--beside the ICU category--other unrevealed factors determine antibiotic use.

Effects of reducing beta-lactam antibiotic pressure on intestinal colonization of antibiotic-resistant gram-negative bacteria

Background

We determined the effects of two antibiotic policies (predominance of either β-lactam antibiotics or fluroquinolones) on acquisition with third-generation cephalosporin-resistant Enterobacteriaceae (CRE) and fluoroquinolone-resistant CRE (FCRE) in two ICUs, with monitoring of other variables that may influence acquisition.

Methods

After an 8-month baseline period, units were randomized to a predominant β-lactam antibiotic regimen (weekly cycling of ceftriaxone, amoxicillin–clavulanic acid and fluroquinolones) or a fluoroquinolone regimen for 3 months, with cross-over for another 3 months. Acquisition of CRE and FCRE was determined by microbiological surveillance.

Results

During baseline, acquisition rates for CRE and FCRE were 14/1,000 and 2/1,000 patient days at risk, respectively. Cross-transmission of CRE accounted for ≤25% of acquisitions, and CRE acquisition was associated with the use of β-lactam antibiotics (amoxicillin–clavulanic acid in particular). As compared to baseline, β-lactam antibiotic use [in defined daily dose (DDD)/1,000 patient days] was reduced from 854 to 526 (−39%) and 555 (−35%) during both intervention periods. Fluoroquinolone use was increased from 150 and 129 DDD/1,000 patient days in baseline and the β-lactam period to 514 DDD/1,000 patient days (+243%) in the fluoroquinolone period. Reductions in β-lactam use were not associated with reduced CRE acquisition [adjusted HRs were 1.0 (95% CR: 0.5–2.2) and 1.1 (95% CI: 0.5–2.5) during both periods, respectively]. Increased use of fluoroquinolones was associated with increased acquisition of FCRE [adjusted HR 4.1 (95% CI: 1.4–11.9; p < 0.01]. Infection control variables remained comparable during all periods.

Conclusion

A 35–39% reduction of β-lactam exposure was not associated with reduced acquisition of CRE, whereas a 243% increase of fluoroquinolone use increased acquisition of FCRE.

Impact of a Reduction in the Use of High-Risk Antibiotics on the Course of an Epidemic of Clostridium difficile-Associated Disease Caused by the Hypervirulent NAP1/027 Strain

A series of measures were implemented, in a secondary/tertiary-care hospital in Quebec, to control an epidemic of nosocomial Clostridium difficile-associated disease (n-CDAD) caused by a virulent strain; these measures included the development of a nonrestrictive antimicrobial stewardship program. Interrupted time-series analysis was used to evaluate the impact of these measures on n-CDAD incidence. From 2003-2004 to 2005-2006, total and targeted antibiotic consumption, respectively, decreased by 23% and 54%, and the incidence of n-CDAD decreased by 60%. No change in n-CDAD incidence was noted after strengthening of infection control procedures (P=.63), but implementation of the antimicrobial stewardship program was followed by a marked reduction in incidence (P=.007). This suggests that nonrestrictive measures to optimize antibiotic usage can yield exceptional results when physicians are motivated and that such measures should be a mandatory component of n-CDAD control. The inefficacy of infection control measures targeting transmission through hospital personnel might be a result of their implementation late in the epidemic, when the environment was heavily contaminated with spores.

Antimicrobial use in Finnish acute care hospitals: data from national prevalence survey, 2005

OBJECTIVES

In Finland, use of antimicrobials in ambulatory care is moderate, but some reports suggest that hospital use is higher than in other European countries. We evaluated the amount and type of antimicrobials administered in Finnish acute care hospitals.

PATIENTS AND METHODS

We analysed data collected in the national prevalence survey of nosocomial infections (NIs) during February-March 2005 in all tertiary care, all secondary care and 25% of other acute care hospitals. All inpatients present on the study day in acute care wards for adults were included (n=8234). The names and use-days of antimicrobials in Anatomical Therapeutic Class groups J01-J05 were collected on the study day and retrospectively for the previous 6 days.

RESULTS

On the study day, 39% of patients had received at least one, 14% at least two and 3% at least three antimicrobials; patients with NI represented 21%, 29% and 45% of these groups, respectively. The prevalence of patients receiving any antimicrobial was 53% in intensive care patients and varied in other specialties from 0% in ophthalmology to 63% in dental and oral surgery. Within a 7 day period, the total use of antibacterial agents (J01) was 64 use-days per 100 patient-days. Cephalosporins were the most frequently used antimicrobials, followed by quinolones and metronidazole.

CONCLUSIONS

The prevalence and spectrum of antimicrobial use in Finnish acute care hospitals were high. NI patients contributed markedly to the total usage. The NI survey with a 7 day data collection period provided insights into the use-density of antimicrobials.

Antibiotic use in two cohorts of German intensive care units

Antibiotic use was evaluated in two cohorts of intensive care units (ICUs) in Germany. One cohort included ICUs participating in a surveillance programme (N=34) collecting antibiotic use and bacterial resistance data, with quarterly feedback. The second ICU cohort was from a cross-sectional study and represented a sample from hospitals in South-west Germany (N=58). Two dose definitions were used. These were the World Health Organization/Anatomical Therapeutic Chemical Classification (ATC) 2001 definition of defined daily dose (DDD), and a definition of recommended daily dose (RDD) that better reflected the currently prescribed dosages of parenteral drugs for hospitalized patients. Data were expressed as DDD or RDD per 100 patient-days. It was determined whether hospital size and affiliation, year of study and ICU type had an influence on overall use of antibiotics. Overall use differed between the two ICU cohorts irrespective of the dose definitions used. High use of antibiotics was primarily associated with hospital affiliation (university vs non-university) and hospital size. Mean overall use of antibiotics in non-university hospital ICUs ranged between 106 and 111 DDD/100 (59 and 67 RDD/100) for different hospital size categories, compared with 140 DDD/100 (87 RDD/100) in university hospital ICUs. In conclusion, in order to compare the use of antibiotics between ICU cohorts and to assess trends over time, data adjustment is required for hospital affiliation and size.

Hospital consumption of antibiotics in 15 European countries: results of the ESAC Retrospective Data Collection (1997–2002)

OBJECTIVES

To collect reliable, comparable and publicly available data on hospital use of antibiotics in Europe aggregated at the national level (1997-2002).

METHODS

Consumption data of systemic antibiotics in Anatomical Therapeutic Chemical (ATC) class J01 were collected and expressed in defined daily doses (DDD) per 1000 inhabitants per day. Valid data for 2002 were available for 15 countries, and 6 year trends for 10 countries. Comparison with ambulatory care (AC) consumption data was possible in 14 countries.

RESULTS

In 2002, median national hospital antibiotic consumption in Europe was 2.1 DDD/1000 inhabitants/day in Europe, ranging from 3.9 in Finland and France to 1.3 in Norway and Sweden. Hospital care (HC) consumption as a proportion of total antibiotic consumption ranged from 17.8% to 6.4%. The consumption of hospital-specific antibiotics ranged from 0.43 DDD/1000 inhabitants/day in Greece and 0.08 in Sweden. Six-year trends in consumption were stable, except for rising co-amoxiclav exposure and more rapid market penetration of new antibiotics (e.g. levofloxacin) in some countries. There was a strong, positive correlation between the extent of antibiotic use in AC and in HC (Spearman coefficient 0.745; P = 0.002), both for overall use and for use of five main classes (not macrolides and 'others'). In contrast to AC consumption no substantial seasonal variation in consumption was observed.

CONCLUSIONS

It was cumbersome but feasible to collect ecological data on hospital antibiotic consumption in a set of 15 European countries on a retrospective basis, illustrating substantial cross-national variations in the extent and distribution of exposure to antibiotics in hospital care.