Impact of long-term macrolide therapy on the evaluation indicator of outpatient oral antimicrobial use according to the AWaRe classification

Area of Science:

• Pharmacology
• Public Health
• Infectious Diseases

Background:

• The World Health Organization (WHO) introduced the AWaRe classification to assess antimicrobial selection appropriateness.
• The influence of long-term macrolide therapy on this indicator is not well understood.
• Antimicrobial usage (AMU) in outpatient settings requires careful monitoring for appropriate selection.

Purpose of the Study:

• To investigate the impact of long-term macrolide therapy on the WHO's AWaRe classification indicator for outpatient oral antimicrobial use.
• To analyze macrolide prescription patterns in relation to patient demographics and duration of therapy.
• To inform strategies for optimizing antimicrobial stewardship in ambulatory care.

Main Methods:

• Analysis of a large claims database (JMDC) including 2.66 million outpatients prescribed oral antimicrobials in 2022.
• Calculation of patient ratios and AMU stratified by age groups (<15, 15-64, ≥65 years) and prescription durations (1-91+ days).
• AMU was corrected for defined daily doses and categorized using the AWaRe classification; long-term macrolide therapy was defined as ≥91 days of use, particularly in patients with chronic airway disease.

Main Results:

• Macrolides constituted over 30% of total oral AMU across all age demographics.
• In elderly patients (≥65 years), 11.2% received macrolides for ≥91 days, representing 66.4% of total macrolide use in this group.
• A positive correlation was observed between prescription duration and the prevalence of chronic airway diseases among macrolide recipients.

Conclusions:

• Long-term macrolide therapy, particularly in the elderly and those with chronic airway diseases, substantially influences outpatient oral AMU metrics.
• The findings underscore the necessity of incorporating the impact of extended macrolide use into assessments of antimicrobial appropriateness via the AWaRe classification.
• Future antimicrobial stewardship initiatives should address specific patterns of long-term macrolide utilization.