Impact of an infectious disease specialist on antifungal use: an interrupted time-series analysis in a tertiary hospital in Tokyo

Abstract

Antimicrobial stewardship programmes are considered essential for optimizing antimicrobial use in order to improve patient outcomes, reduce the number of adverse sequelae, prevent resistance, and ensure cost-effective therapy. To assess the efficacy and the limitations of antifungal antimicrobial stewardship programmes. A bundle to manage infectious diseases was implemented in our hospital in October 2010. Data regarding antimicrobial use density (AUD) from April 2006 to May 2016 were collected. Trends in AUD were assessed using an interrupted time-series model for three separate periods: the pre-bundle, the bundle implementation, and the long-term follow-up periods. The primary and secondary outcomes were AUD (defined daily dose (DDD) per 1000 patient-days) of intravenous antifungals and expenditure on antifungals per fiscal year, respectively. The AUD for all intravenous antifungals decreased from 26.1 in 2006 to 9.9 in 2015. Whereas the change in the trend during the pre-bundle period was not significant (slope: 0.062; 95% confidence interval (CI):-0.180 to 0.305), a significant decrease was observed in the bundle implementation period (slope:-0.535; 95% CI:-0.907 to-0.164). The trend slowed during the long-term follow-up period (slope:-0.040; 95% CI:-0.218 to 0.138). Total expenditure on antifungals decreased by 73%, from ¥52,354,411 in fiscal year 2006 to ¥14,073,099 in fiscal year 2015. The bundle significantly reduced the use of antifungals and decreased costs over time, but this effect was limited in that it had stabilized within three years.