Consumption of macrolides, lincosamides and streptogramins in the community, European Union/European Economic Area, 1997-2017

Clinically important interactions of macrolides and tetracyclines with dietary interventions-a systematic review with meta-analyses

BACKGROUND

Effective management of drug-food interactions is crucial for enhancing antibiotics' efficacy/safety. Adhering to PRISMA guidelines, we conducted a systematic review to assess the impact of dietary interventions on the bioavailability of 15 macrolides and 10 tetracyclines.

METHODS

We included studies examining the influence of food, beverages, antacids, and mineral supplements on the pharmacokinetic parameters of orally administered macrolides and tetracyclines. We searched Medline (via PubMed), Embase and Cochrane Library databases up to December 2022. Risk of bias was assessed using Cochrane and NIH tools. Quantitative analyses were conducted if two or more comparable food-effect studies were available; otherwise, a qualitative summary was provided.

RESULTS

We included 120 studies from 97 reports. Meta-analyses were conducted for 8 macrolides and 4 tetracyclines, with qualitative synthesis for 10 and 9, respectively. About 64% of the studies were open-label, crossover designs. Our assessment found that 37% of the studies had a high risk of bias, while only 6% had low risk. Food significantly affected 10 of 13 macrolides (77%) and 6 of 7 tetracyclines (86%). High positive effects on bioavailability were seen with extended-release azithromycin and clarithromycin, and erythromycin estolate. High negative impacts were observed with erythromycin propionate and stearate, azithromycin capsules, demeclocycline and omadacycline. Antacids and mineral supplements significantly decreased tetracyclines absorption. Milk and grapefruit juice showed variable impacts on absorption.

DISCUSSION

Interactions depend on antibiotics' physicochemical characteristics, intervention type, drug formulation and potential patient factors. The quality of evidence was rated low due to outdated studies, methodological diversity and unequal data availability.

Recent development and fighting strategies for lincosamide antibiotic resistance

SUMMARYLincosamides constitute an important class of antibiotics used against a wide range of pathogens, including methicillin-resistant Staphylococcus aureus. However, due to the misuse of lincosamide and co-selection pressure, the resistance to lincosamide has become a serious concern. It is urgently needed to carefully understand the phenomenon and mechanism of lincosamide resistance to effectively prevent and control lincosamide resistance. To date, six mobile lincosamide resistance classes, including lnu, cfr, erm, vga, lsa, and sal, have been identified. These lincosamide resistance genes are frequently found on mobile genetic elements (MGEs), such as plasmids, transposons, integrative and conjugative elements, genomic islands, and prophages. Additionally, MGEs harbor the genes that confer resistance not only to antimicrobial agents of other classes but also to metals and biocides. The ultimate purpose of discovering and summarizing bacterial resistance is to prevent, control, and combat resistance effectively. This review highlights four promising strategies, including chemical modification of antibiotics, the development of antimicrobial peptides, the initiation of bacterial self-destruct program, and antimicrobial stewardship, to fight against resistance and safeguard global health.

Together or Apart? Revealing the Impact of Dietary Interventions on Bioavailability of Quinolones: A Systematic Review with Meta-analyses

BACKGROUND AND OBJECTIVE

Managing drug-food interactions is essential for optimizing the effectiveness and safety profile of quinolones. Following PRISMA guidelines, we systematically reviewed the influence of dietary interventions on the bioavailability of 22 quinolones.

METHODS

All studies describing or investigating the impact of food, beverages, antacids, and mineral supplements on pharmacokinetic parameters or pharmacokinetic/pharmacodynamic indices of orally taken quinolones were considered for inclusion. We excluded reviews, in vitro and in silico studies, studies performed on animals, and those involving alcohol. We performed the search in Medline (via PubMed), Embase, and Cochrane Library, covering reports from database inception to December 2022. We used the following tools to assess the risk of bias: version 2 of the Cochrane risk-of-bias tool for parallel trials, the Cochrane risk-of-bias tool for cross-over studies, and the NIH quality assessment tool for before-after studies. We performed quantitative analyses for each quinolone if two or more food-effect studies with specified and comparable study designs were available. If meta-analyses were not applicable, we qualitatively summarized the results.

RESULTS

We included 109 studies from 101 reports. Meta-analyses were conducted for 12 antibiotics and qualitative synthesis was employed for the remaining drugs. Of the studies, 60.5% were open-label, cross-over, as recommended by FDA. We judged 46% of studies as having a high risk of bias and only 4% of having a low risk of bias. Among 19 quinolones with available food impact data, 14 (74%) had potentially clinically important interactions. For nalidixic acid, oxolinic acid, and tosufloxacin, food exerted a high positive impact on bioavailability (AUC or Cmax increased by > 45%), whereas, for all the remaining drugs, postprandial absorption was lower. The most significant negative influence of food (AUC or Cmax decreased by > 40%) occurred for delafloxacin capsules and norfloxacin, whereas the moderate influence (AUC or Cmax decreased by 30-40%) occurred for nemonoxacin and rufloxacin. All 14 analysed quinolones showed a substantial reduction in bioavailability when co-administered with antacids and mineral supplements, except for calcium preparations. The impact of beverages was evaluated for 10 quinolones, with 50% experiencing significantly reduced absorption in the presence of milk (the highest negative impact for ciprofloxacin). Moreover, both ciprofloxacin and levofloxacin demonstrated compromised bioavailability when consumed with orange juice, particularly calcium-fortified.

DISCUSSION

Several factors may influence interactions, including the physicochemical characteristics of quinolones, the type of intervention, drug formulation, and the patient's health status. We assessed the quality of evidence as low due to the poor actuality of included studies, their methodological diversity, and uneven data availability for individual drugs.

A novel 12-membered ring non-antibiotic macrolide EM982 attenuates cytokine production by inhibiting IKKβ and IκBα phosphorylation

Antimicrobial resistance poses a serious threat to human health worldwide and its incidence continues to increase owing to the overuse of antibiotics and other factors. Macrolide antibiotics such as erythromycin (EM) have immunomodulatory effects in addition to their antibacterial activity. Long-term, low-dose administration of macrolides has shown clinical benefits in treating non-infectious inflammatory respiratory diseases. However, this practice may also increase the emergence of drug-resistant bacteria. In this study, we synthesized a series of EM derivatives, and screened them for two criteria: (i) lack of antibacterial activity and (ii) ability to suppress tumor necrosis factor-α (TNF-α) production in THP-1 cells stimulated with lipopolysaccharide. Among the 37 synthesized derivatives, we identified a novel 12-membered ring macrolide EM982 that lacked antibacterial activity against Staphylococcus aureus and suppressed the production of TNF-α and other cytokines. The effects of EM982 on Toll-like receptor 4 (TLR4) signaling were analyzed using a reporter assay and Western blotting. The reporter assay showed that EM982 suppressed the activation of transcription factors, NF-κB and/or activator protein 1 (AP-1), in HEK293 cells expressing human TLR4. Western blotting showed that EM982 inhibited the phosphorylation of both IκB kinase (IKK) β and IκBα, which function upstream of NF-κB, whereas it did not affect the phosphorylation of p38 mitogen-activated protein kinase, extracellular signal-regulated kinase, and c-Jun N-terminal kinase, which act upstream of AP-1. These results suggest that EM982 suppresses cytokine production by inhibiting phosphorylation of IKKβ and IκBα, resulting in the inactivation of NF-κB.

An increase in erythromycin resistance in methicillin-susceptible Staphylococcus aureus from blood correlates with the use of macrolide/lincosamide/streptogramin antibiotics. EARS-Net Spain (2004-2020)

Objectives

To describe and analyse erythromycin resistance trends in blood isolates of Staphylococcus aureus (EARS-Net Spain, 2004-2020) and the association of these trends with the consumption of macrolide, lincosamide, and streptogramin B (MLSB) antibiotics. To assess molecular changes that could be involved in erythromycin resistance trends by whole genome analysis of representative isolates.

Materials and methods

We collected antibiotic susceptibility data for all first-blood S. aureus isolates in patients from 47 Spanish hospitals according to EARS-Net criteria. MLSB antibiotic consumption was obtained from the Spanish Agency for Medicines and Medical Devices (2008-2020). We sequenced 137 representative isolates for core genome multilocus sequence typing, resistome and virulome analysis.

Results

For the 36,612 invasive S. aureus isolates, methicillin resistance decreased from 26.4% in 2004 to 22.4% in 2020. Erythromycin resistance in methicillin-susceptible S. aureus (MSSA) increased from 13.6% in 2004 to 28.9% in 2020 (p < 0.001); however, it decreased from 68.7 to 61.8% (p < 0.0001) in methicillin-resistant S. aureus (MRSA). Total consumption of MLSB antibiotics increased from 2.72 defined daily doses per 1,000 inhabitants per day (DID) in 2014 to 3.24 DID in 2016. By WGS, the macrolide resistance genes detected were erm (59.8%), msrA (46%), and mphC (45.2%). The erm genes were more prevalent in MSSA (44/57, 77.2%) than in MRSA (38/80, 47.5%). Most of the erm genes identified in MSSA after 2013 differed from the predominant ermC gene (17/22, 77.3%), largely because ermT was significantly associated with MSSA after 2013 (11/29, 37.9%). All 13 ermT isolates in this study, except one, belonged to ST398 and came from 10 hospitals and six Spanish provinces.

Conclusion

The significant increase in erythromycin resistance in blood MSSA correlated with the consumption of the MLSB antibiotics in Spain. These preliminary data seem support the hypothesis that the human ST398 MSSA clade with ermT-mediated resistance to erythromycin may be involved in this trend.

The Impact of Long-Term Macrolide Exposure on the Gut Microbiome and Its Implications for Metabolic Control

Long-term low-dose macrolide therapy is now widely used in the treatment of chronic respiratory diseases for its immune-modulating effects, although the antimicrobial properties of macrolides can also have collateral impacts on the gut microbiome. We investigated whether such treatment altered intestinal commensal microbiology and whether any such changes affected systemic immune and metabolic regulation. In healthy adults exposed to 4 weeks of low-dose erythromycin or azithromycin, as used clinically, we observed consistent shifts in gut microbiome composition, with a reduction in microbial capacity related to carbohydrate metabolism and short-chain fatty acid biosynthesis. These changes were accompanied by alterations in systemic biomarkers relating to immune (interleukin 5 [IL-5], IL-10, monocyte chemoattractant protein 1 [MCP-1]) and metabolic (serotonin [5-HT], C-peptide) homeostasis. Transplantation of erythromycin-exposed murine microbiota into germ-free mice demonstrated that changes in metabolic homeostasis and gastrointestinal motility, but not systemic immune regulation, resulted from changes in intestinal microbiology caused by macrolide treatment. Our findings highlight the potential for long-term low-dose macrolide therapy to influence host physiology via alteration of the gut microbiome. IMPORTANCE Long-term macrolide therapy is widely used in chronic respiratory diseases although its antibacterial activity can also affect the gut microbiota, a key regulator of host physiology. Macrolide-associated studies on the gut microbiota have been limited to short antibiotic courses and have not examined its consequences for host immune and metabolic regulation. This study revealed that long-term macrolides depleted keystone bacteria and impacted host regulation, mediated directly by macrolide activity or indirectly by alterations to the gut microbiota. Understanding these macrolide-associated mechanisms will contribute to identifying the risk of long-term exposure and highlights the importance of targeted therapy for maintenance of the gut microbiota.

Risk ranking of macrolide antibiotics - Release levels, resistance formation potential and ecological risk

Antibiotic resistance (AR) development in natural water bodies is a significant source of concern. Macrolide antibiotics in particular have been identified as pollutants of concern for AR development throughout the literature, as well as by state and international authorities. This study utilises a probabilistic model to examine the risk of AR development arising from human-use macrolide residues, utilising administration rates from Ireland as a case study. Stages modelled included level of administration, excretion, degradation in wastewater, removal in wastewater treatment, assuming conventional activated sludge (CAS) treatment, and dilution. Release estimates per day, as well as risk quotient values for antibiotic resistance development and ecological impact, are generated for erythromycin, clarithromycin, and azithromycin. In the modelled scenario in which conventional activated sludge treatment is utilised in wastewater treatment, this model ranks risk of resistance development for each antibiotic in the order clarithromycin > azithromycin > erythromycin, with mean risk quotient values of 0.50, 0.34 and 0.12, respectively. A membrane bioreactor scenario was also modelled, which reduced risk quotient values for all three macrolides by at least 50 %. Risk of ecological impact for each antibiotic was also examined, by comparing environmental concentrations predicted to safety limits based on toxicity data for cyanobacteria and other organisms from the literature, with azithromycin being identified as the macrolide of highest risk. This study compares and quantifies the risk of resistance development and ecological impact for a high-risk antibiotic group in the Irish context, and demonstrates the potential for risk reduction achieved by adoption of alternative (e.g. membrane bioreactor) technology.

Molecular Epidemiology, Antimicrobial Susceptibility, and Clinical Features of Methicillin-Resistant Staphylococcus aureus Bloodstream Infections over 30 Years in Barcelona, Spain (1990-2019)

Methicillin-resistant Staphylococcus aureus bloodstream infections (MRSA-BSI) are a significant cause of mortality. We analysed the evolution of the molecular and clinical epidemiology of MRSA-BSI (n = 784) in adult patients (Barcelona, 1990−2019). Isolates were tested for antimicrobial susceptibility and genotyped (PFGE), and a selection was sequenced (WGS) to characterise the pangenome and mechanisms underlying antimicrobial resistance. Increases in patient age (60 to 71 years), comorbidities (Charlson’s index > 2, 10% to 94%), community-onset healthcare-associated acquisition (9% to 60%), and 30-day mortality (28% to 36%) were observed during the 1990−1995 and 2014−2019 periods. The proportion of catheter-related BSIs fell from 57% to 20%. Current MRSA-BSIs are caused by CC5-IV and an upward trend of CC8-IV and CC22-IV clones. CC5 and CC8 had the lowest core genome proportions. Antimicrobial resistance rates fell, and only ciprofloxacin, tobramycin, and erythromycin remained high (>50%) due to GyrA/GrlA changes, the presence of aminoglycoside-modifying enzymes (AAC(6′)-Ie-APH(2″)-Ia and ANT(4′)-Ia), and mph(C)/msr(A) or erm (C) genes. Two CC22-IV strains showed daptomycin resistance (MprF substitutions). MRSA-BSI has become healthcare-associated, affecting elderly patients with comorbidities and causing high mortality rates. Clonal replacement with CC5-IV and CC8-IV clones resulted in lower antimicrobial resistance rates. The increased frequency of the successful CC22-IV, associated with daptomycin resistance, should be monitored.

An Overview of Macrolide Resistance in Streptococci: Prevalence, Mobile Elements and Dynamics

Streptococcal infections are usually treated with beta-lactam antibiotics, but, in case of allergic patients or reduced antibiotic susceptibility, macrolides and fluoroquinolones are the main alternatives. This work focuses on studying macrolide resistance rates, genetic associated determinants and antibiotic consumption data in Spain, Europe and also on a global scale. Macrolide resistance (MR) determinants, such as ribosomal methylases (erm(B), erm(TR), erm(T)) or active antibiotic efflux pumps and ribosomal protectors (mef(A/E)-mrs(D)), are differently distributed worldwide and associated with different clonal lineages and mobile genetic elements. MR rates vary together depending on clonal dynamics and on antibiotic consumption applying selective pressure. Among Streptococcus, higher MR rates are found in the viridans group, Streptococcus pneumoniae and Streptococcus agalactiae, and lower MR rates are described in Streptococcus pyogenes. When considering different geographic areas, higher resistance rates are usually found in East-Asian countries and milder or lower in the US and Europe. Unfortunately, the availability of data varies also between countries; it is scarce in low- and middle- income countries from Africa and South America. Thus, surveillance studies of macrolide resistance rates and the resistance determinants involved should be promoted to complete global knowledge among macrolide resistance dynamics.

Evaluation and comparison of antibiotic susceptibility profiles of Streptomyces spp. from clinical specimens revealed common and region-dependent resistance patterns

Notwithstanding the fact that streptomycetes are overlooked in clinical laboratories, studies describing their occurrence in disease and potential pathogenicity are emerging. Information on their species diversity in clinical specimens, aetiology and appropriate therapeutic treatment is scarce. We identified and evaluated the antibiotic susceptibility profile of 84 Streptomyces clinical isolates from the Czech Republic. In the absence of appropriate disk diffusion (DD) breakpoints for antibiotic susceptibility testing (AST) of Streptomyces spp., we determined DD breakpoints by correlation with the broth microdilution method and by the distribution of zone diameters among isolates. Correlation accuracy was high for 9 antibiotics, leading to the establishment of the most valid DD breakpoints for Streptomyces antibiotic susceptibility evaluation so far. Clinical strains belonged to 17 different phylotypes dominated by a cluster of strains sharing the same percentage of 16S rRNA gene sequence identity with more than one species (S. albidoflavus group, S. hydrogenans, S. resistomycificus, S. griseochromogenes; 70% of isolates). AST results showed that Streptomyces exhibited intrinsic resistance to penicillin, general susceptibility to amikacin, gentamycin, vancomycin and linezolid, and high percentage of susceptibility to tetracyclines and clarithromycin. For the remaining antibiotics, AST showed inter- and intra-species variations when compared to available literature (erythromycin, trimethoprim-sulfamethoxazole), indicating a region-dependent rather than species-specific patterns.

Study of the indications for macrolide prescriptions in a Colombian population

Introduction

The inappropriate use of antibiotics is associated with a greater risk for antimicrobial resistance, high health care costs, adverse events, and worse clinical outcomes.

Objective

To determine the prescription patterns and approved and nonapproved indications for macrolides in a group of patients from Colombia.

Materials and methods

This was a cross-sectional study on the indications for the use of macrolides in outpatients registered in a drug-dispensing database of approximately 8.5 million people affiliated with the Colombian health system. Sociodemographic, pharmacological, and clinical variables were considered.

Results

A total of 9.344 patients had received a macrolide prescription; their median age was 40.1 years (interquartile range: 27.1-53.3 years) and 58.3% were women. The most commonly prescribed macrolide was azithromycin (38.8%) most frequently for Helicobacter pylori infection (15.9%) and pneumonia treatment (15.8%). A total of 31.3% of the prescriptions were used for unapproved indications: common cold (7.8%), COVID-19 (4.0%), and acute bronchitis (3.5%). Residence in the Caribbean region (OR=1.17; 95%CI 1.05-1.31), dental prescriptions (OR=2.75; 95%CI 1.91-3.96), presence of chronic respiratory comorbidities (OR=1.30; 95%CI 1.08-1.56), and prescription of erythromycin (OR=3.66; 95%CI 3.24-4.14) or azithromycin (OR=2.15; 95%CI 1,92-2.41) were associated with a higher probability of macrolide use for unapproved indications while being 18-64 years old (OR=0.81; 95%CI 0.71-0.93) or 65 years or older (OR=0.77; 95%CI 0.63-0.94) and residing in Bogotá-Cundinamarca (OR=0.74; 95%CI 0.65-0.85) were associated with reduced risk.

Conclusions

Most patients received macrolides for respiratory tract infections; erythromycin and azithromycin were used for unapproved indications in people under 18 years of age and those with chronic respiratory diseases.

Consumption of Antibacterials for Systemic Use in Slovakia: A National Study and the Quality Indicators for Outpatient Antibiotic Use

This paper aims to analyse the consumption of antibiotics in the Slovak health care system from 2011 to 2020. The data source on the consumption of antibiotics is sales data from SUKL and NCZI. The study employed the ATC/DDD Index and focused on the consumption of antibiotics in the primary care sector. Total antibiotic consumption decreased from 19.21 DID in 2011 to 13.16 DID in 2020. Consumption of beta-lactamase-sensitive penicillins, expressed as a percentage of the total consumption of antibiotics, decreased from 8.4% in 2011 to 4.2% in 2020. Consumption of the combination of penicillins, including beta-lactamase inhibitor, expressed as a percentage of the total consumption of antibiotics, increased from 16.2% in 2011 to 17.9% in 2020. Consumption of third- and fourth-generation cephalosporins, expressed as the percentage of the total consumption of antibiotics, increased from 2.0% in 2011 to 4.6% in 2020. Consumption of fluoroquinolones, expressed as the percentage of the total consumption of antibiotics, decreased from 10.7% in 2011 to 8.6% in 2020. Overall, antibiotic consumption significantly changed in Slovakia from 2011 to 2020. The ratio of the consumption of broad-spectrum to the consumption of narrow-spectrum penicillins, cephalosporins and macrolides decreased from 14.98 in 2011 to 13.38 in 2020.

Quality appraisal of antibiotic consumption in the community, European Union/European Economic Area, 2009 and 2017

Objectives

The quality of antibiotic consumption in the community can be assessed using 12 drug-specific quality indicators (DSQIs) developed by the European Surveillance of Antimicrobial Consumption (ESAC) project. We compared quality in 2009 and 2017 in the EU/European Economic Area (EEA) and evaluated the impact of using different DDD values (ATC/DDD indices 2011 and 2019) for the 2009 quality assessment using these DSQIs and a joint scientific opinion (JSO) indicator.

Methods

We calculated the 12 DSQIs and the JSO indicator for 2017 and for 2009 for EU/EEA countries able to deliver values. For each of the indicators we grouped the 2017 and 2009 indicator values into four quartiles. To evaluate changes in quality between 2009 and 2017, we used the quartile distribution of the 2009 indicator values in 30 EU/EEA countries as benchmarks. In addition, we compared the quality assessment for 2009 using the ATC/DDD indices 2011 and 2019.

Results

In 2017, a difference in the quality of antibiotic consumption in the community between northern and southern EU/EEA countries remained, but also several eastern EU/EEA countries shifted towards lower quality. Quality of antibiotic consumption decreased between 2009 and 2017 in particular indicator values for penicillin, quinolone, relative β-lactam and broad- versus narrow-spectrum antibiotic consumption, and seasonal variation. Using different ATC/DDD indices did not substantially change countries’ ranking based on their DSQI values.

Conclusions

The quality of antibiotic consumption in the community as measured by the DSQIs further decreased between 2009 and 2017, especially in Southern and Eastern European countries. A continuous effort to improve antibiotic consumption is essential to reduce antibiotic consumption in general and the use of broad-spectrum antibiotics in particular.

Consumption of antibiotics in the community, European Union/European Economic Area, 1997-2017

Objectives

Data on antibiotic consumption in the community were collected from 30 EU/EEA countries over two decades. This article reviews temporal trends, seasonal variation, presence of change-points and changes in the composition of the main antibiotic groups.

Methods

For the period 1997–2017, data on consumption of antibiotics, i.e. antibacterials for systemic use (ATC group J01), in the community, aggregated at the level of the active substance, were collected using the WHO ATC/DDD methodology (ATC/DDD index 2019). Consumption was expressed in DDD per 1000 inhabitants per day and in packages per 1000 inhabitants per day. Antibiotic consumption was analysed based on ATC-3 groups, and presented as trends, seasonal variation, presence of change-points and compositional changes.

Results

In 2017, antibiotic consumption in the community expressed in DDD per 1000 inhabitants per day varied by a factor 3.6 between countries with the highest (Greece) and the lowest (the Netherlands) consumption. Antibiotic consumption in the EU/EEA did not change significantly over time. Antibiotic consumption showed a significant seasonal variation, which decreased over time. The number of DDD per package significantly increased over time. The proportional consumption of sulphonamides and trimethoprim (J01E) relative to other groups significantly decreased over time, while the proportional consumption of other antibacterials (J01X) relative to other groups significantly increased over time.

Conclusions

Overall, antibiotic consumption in the community in the EU/EEA did not change during 1997–2017, while seasonal variation consistently decreased over time. The number of DDD per package increased during 1997–2017.

Change-points in antibiotic consumption in the community, European Union/European Economic Area, 1997-2017

OBJECTIVES

Surveillance of antibiotic consumption in the community is of utmost importance to inform and evaluate control strategies. Data on two decades of antibiotic consumption in the community were collected from 30 EU/European Economic Area (EEA) countries. This article reviews temporal trends and the presence of abrupt changes in subgroups of relevance in antimicrobial stewardship.

METHODS

For the period 1997-2017, data on yearly antibiotic consumption in the community, aggregated at the level of the active substance, were collected using the WHO ATC classification and expressed in DDD (ATC/DDD index 2019) per 1000 inhabitants per day. We applied a range of non-linear mixed models to assess the presence of changes in the consumption of antibacterials for systemic use (ATC group J01) and eight antibiotic subgroups.

RESULTS

For the majority of the studied groups, a country-specific change-point model provided the best fit. Depending on the antibiotic group/subgroup and on the country, change-points were spread out between 2000 and 2013.

CONCLUSIONS

Due to the heterogeneity in antibiotic consumption in the community across EU/EEA countries, a country-specific change-point model provided the better fit. Given the limitations of this model, our recommendation for the included countries is to carefully interpret the country-specific results presented in this article and to use the tutorial included in this series to conduct their own change-point analysis when evaluating the impact of changes in regulations, public awareness campaigns, and other national interventions to improve antibiotic consumption in the community.

Analysing the trend over time of antibiotic consumption in the community: a tutorial on the detection of common change-points

OBJECTIVES

This tutorial describes and illustrates statistical methods to detect time trends possibly including abrupt changes (referred to as change-points) in the consumption of antibiotics in the community.

METHODS

For the period 1997-2017, data on consumption of antibacterials for systemic use (ATC group J01) in the community, aggregated at the level of the active substance, were collected using the WHO ATC/DDD methodology and expressed in DDD (ATC/DDD index 2019) per 1000 inhabitants per day. Trends over time and presence of common change-points were studied through a set of non-linear mixed models.

RESULTS

After a thorough description of the set of models used to assess the time trend and presence of common change-points herein, the methodology was applied to the consumption of antibacterials for systemic use (ATC J01) in 25 EU/European Economic Area (EEA) countries. The best fit was obtained for a model including two change-points: one in the first quarter of 2004 and one in the last quarter of 2008.

CONCLUSIONS

Allowing for the inclusion of common change-points improved model fit. Individual countries investigating changes in their antibiotic consumption pattern can use this tutorial to analyse their country data.

Consumption of antibiotics in the community, European Union/European Economic Area, 1997-2017: data collection, management and analysis

OBJECTIVES

This article introduces a series of articles on antibiotic consumption in the community between 1997 and 2017, which provide an update of previous articles covering the periods 1997-2003 and 1997-2009.

METHODS

In this article, differences in participating countries, the ATC/DDD classification system, and data collection, validation and analysis between the current and previous series are described.

RESULTS

In the previous series, 33 European countries provided valid data for further analysis, while the current series focused on 30 countries belonging to the EU or the European Economic Area (EEA). For both series, data were collected in accordance with the WHO ATC classification system. While the previous series reported data in accordance with the ATC/DDD index 2011, the current series employed the ATC/DDD index 2019. Both series focused on consumption of antibacterials for systemic use (ATC J01) and collected data expressed in DDD per 1000 inhabitants per day and packages per 1000 inhabitants per day. When studying consumption expressed in packages per 1000 inhabitants per day, countries reporting total care data, i.e. community and hospital sector combined, were included in the previous series but excluded in the current series. While the previous series used non-linear mixed models to evaluate time trends in antibiotic consumption, the current series allowed for inclusion of change-points with a data-driven location. In addition, both series assessed the composition and quality of antibiotic consumption in the EU/EEA.

CONCLUSIONS

The updated analyses of two decades of ESAC-Net data provide the most comprehensive and detailed description of antibiotic consumption in the community in Europe.