Antibiotic misuse: How to evaluate the costs?

Objective: Few studies have assessed the costs associated with the misuse of antibiotics in hospitals in France, despite the value of health economic data to inform antibiotic stewardship activities. We aimed to identify the methodological tools used to assess the cost of antibiotic misuse in hospitals.

Methods: We performed a literature review using the major electronic medical databases. An index of relevance was developed to assess the intrinsic quality of selected articles.

Results: Four hundred and three articles were retrieved, but 35 were selected for analysis. Most studies investigated the inadequate choice of the antibiotic molecule (n=17), the incorrect treatment duration (n=9), and the administration of an inappropriate dosage (n=7). Only three studies were medical/economic evaluations of specific interventions, such as prescription control by pharmacists or the implementation of a new diagnostic test. Considering our aim, the relevance of the studies was limited: few had defined the economic assessment as the primary objective or had detailed the method for calculating costs. Nevertheless, the misuse evaluation was usually better described.

Conclusions: Despite these limits, key factors for measuring antibiotic misuse (i.e., molecule choice, dosage) in relation to the costs (i.e., over/under prescription, hospital stay, staff remuneration) might serve as the basis for the development of a reference methodology to value the costs of misuse. The application of this methodology on identified situations of antibiotic misuse would help hospital decision-makers to justify resource allocation for implementing antimicrobial stewardship activities.