Background:

Antimicrobial stewardship (AMS) programs are essential to the WHO Global and Vietnam national action plan to combat AMR. Our previous qualitative study at seven hospitals in the surveillance network to understand the barriers and opportunities in AMS implementation in Viet Nam have identified several barriers, including a lack of dedicated resources, ineffective communication between doctors and pharmacy and microbiology departments, and the existence of prescribing etiquette among doctors.

Specific salient issues in the prescribing practices include: diagnostic samples are frequently not taken before antibiotic initiation; antibiotics are not adjusted based on culture results; and doctors’ hesitation and lack of confidence in de-escalating and switching from intravenous to oral therapy. Antibiotics were mainly prescribed based on clinical presentations and progress, doctors’ experience, and availability of specific drugs at the pharmacy department.

Internationally, several reviews have shown AMS worked effectively in reducing antimicrobial consumption and improving clinical outcomes. A recent review of studies from LMICs also showed that most studies reported a positive effect. However, it is difficult to draw overall conclusions about the effectiveness of such interventions in these settings because of low study quality, heterogeneity of interventions and outcomes, and under-representation of certain settings. There is a lack of economic analyses of AMS programs to support planning and implementation at the hospital and national levels. To provide more actionable evidence for the adoption of AMS, especially in resource-constrained settings such as Viet Nam, economic evaluations of the interventions are urgently needed.

Aims:

• To assess the cost-effectiveness of AMS programs in the hospitals in Viet Nam;
• To determine the effects of AMS programs on antimicrobial use, patient outcomes and resistance in the study hospitals;
• To reconstruct the AMS implementation processes at each study hospital;
• To identify plausible impact models using interrupted time-series (ITS) design for AMS program on the expected outcomes;
• To assess the attributable costs of resistant infections based on a cohort of carbapenem-resistant Enterobacteriaceae (CRE) hospitalized patients;
• To explores the opportunities for public engagement in antimicrobial stewardship programs in hospitals in Viet Nam.

Study Design:

This study consists of four sub-studies.

In the first sub-study, we will employ an interrupted time-series design to routine data retrieved from the hospital information systems to quantify the effects of AMS programs on key outcomes, including antibiotic use, length of hospital stay, mortality, hospitalization costs and proportions of resistant common bacterial pathogens.

The second sub-study assesses the attributable costs of antibiotic resistance through prospective follow-up assessments in carbapenem-resistant Enterobacterales (CRE) cases and controls, including the indirect costs associated with long-term consequences of infection in patients.

The third sub-study estimates the costs of the AMS interventions using a micro-costing bottom-up time-driven activity-based costing approach, using interviews and observations.

From the costs and effects calculated based on the data collected from these sub-studies, we develop a cost-effectiveness analysis model and evaluate under which circumstances an AMS program would be cost-effective in hospital settings in Viet Nam. In two hospitals (NHTD and Viet Tiep), we conduct a substudy to explore the possibilities for engagement of patients and students in AMS programs. The evidence generated from this study will provide practical information for policy and implementation of interventions to improve antibiotic use in low- and middle-income countries (LMIC) like Viet Nam and recommendations for further research in this area.