Assessing Appropriateness of Antimicrobial Therapy: In the Eye of the Interpreter

Abstract

To address the increase of drug-resistant bacteria and widespread inappropriate use of antimicrobials, many healthcare institutions have implemented antimicrobial stewardship programs to promote appropriate use of antimicrobials and optimize patient outcomes. However, a consensus definition of appropriate use is lacking. We conducted a multicenter observational study to compare 4 definitions of appropriateness--a study site-specific definition, use supported by susceptibility data, use supported by electronic drug information resources (Clinical Pharmacology/Micromedex), or study site principal investigator (PI) opinion-among patients receiving 1 or more of 13 identified antimicrobials. Data were collected for 262 patients. Overall, appropriateness with the 4 definitions ranged from 79% based on PI opinion to 94% based on susceptibility data. No single definition resulted in consistently high appropriate use for all target antimicrobials. For individual antimicrobials, the definitions with the highest rate of appropriate use were Clinical Pharmacology/Micromedex support (6 of 7 antimicrobials) and susceptibility data (5 of 7 antimicrobials). For specific indications, support from susceptibility data resulted in the highest rate of appropriate use (4 of 7 indications). Overall comparisons showed that appropriateness assessed by PI opinion differed significantly compared with other definitions when stratified by either target antimicrobial or indication. The significant variability in the rate of appropriate use highlights the difficulty in developing a standardized definition that can be used to benchmark judicious antimicrobial use.

Antibiotic use and clinical outcomes in the acute setting under management by an infectious diseases acute physician versus other clinical teams: a cohort study

“…Our evaluation did not challenge the validity of the documented working diagnosis, which may have been influenced by preferred antibiotic choice. Judgements on appropriateness can differ substantially depending on the assessor;28 the resource requirements for robust assessment were outside those available for this study. Future work should include investigating whether the relationship between reduced antibiotic use and more admissions is seen in multiple different healthcare settings, and use of newly available larger hospital data sets with electronic prescribing to further elucidate patient and procedural consequences of changes in prescribing strategies.…”

Long-Term Outcomes of an Antimicrobial Stewardship Program Implemented in a Hospital with Low Baseline Antibiotic Use

“…This would be a more meaningful outcome than overall changes in antimicrobial use; unfortunately, standardized measures of appropriateness do not presently exist. 40 For this reason, we assessed a number of clinical outcomes potentially related to antimicrobial use as discussed above. Fourth, we made multiple comparisons without formal statistical adjustment.…”

Measuring the impact of antimicrobial stewardship programs

“…Finally, appropriateness of therapy can be evaluated. This is a more labor intensive method, while it often requires reviewing single patient's files, making it also less objective than 'hard numbers' such as DDDs [54]. However, because the goal of an ASP is optimal therapy (according to protocol), appropriateness of therapy is an outcome measure that directly evaluates the main goal of the intervention.…”