Vol.68 No.4 July 2020

Development of an index for oral antimicrobial use in outpatients at a university hospital

Mitsuhiro Kamada¹⁾, Yuichi Muraki²⁾, Raisa Ogata³⁾, Takafumi Nakano³⁾, Motoyasu Miyazaki¹⁾, Daiki Hagiwara³⁾, Keisuke Sato³⁾, Norihiro Moriwaki³⁾, Shoichi Shiotsuka³⁾, Kentaro Ogata³⁾, Atsushi Togawa⁴⁾, Tohru Takata⁴⁾, Koichi Matsuo¹⁾, Hidetoshi Kamimura³⁾ and Osamu Imakyure¹⁾

¹⁾Department of Pharmacy, Fukuoka Chikusi Hospital, 1-1-1 Zokumyoin, Chikushino, Fukuoka, Japan
²⁾Department of Clinical Pharmacoepidemiology, Kyoto Pharmaceutical University
³⁾Department of Pharmacy, Fukuoka University Hospital
⁴⁾Department of Infection Control and prevention, Fukuoka University Hospital

Abstract

To mitigate antimicrobial resistance (AMR) in Japan, antimicrobial use has recently been regulated based on sales and prescription data. While indices such as defined daily dose (DDD) and days of therapy are used to monitor antimicrobial use in inpatients, similar indices are required for hospital outpatients. Therefore, we devised an index of antimicrobial use that could be used in outpatients and investigated physicians' justifications for prescribing oral antimicrobial agents.
This study was conducted as a retrospective observational study at a single university hospital from November 2016 to October 2017. Consumption amount of antimicrobial agents, numbers of prescriptions, and reasons for prescribing oral antimicrobial agents were recorded. Subsequently, we calculated the DDDs/1,000 outpatients/day (DOD) as an index of antimicrobial use by the outpatients.
The frequencies of antimicrobial use differed between the DOD and numbers of prescriptions. We also found that 73.3% of antimicrobial agents were prescribed at lower doses than the DDD. Outpatient oral antimicrobial prescription, 34% were prescribed for inappropriate reasons or prophylactic purposes. Thus, we recommend more careful antimicrobial stewardship for outpatients at our hospital.
In this study, we show that it is easier to evaluate antimicrobial use by outpatients according to the numbers and details of prescriptions, based on the amount used and the conditions of the prescription, than by using an index. These observations could be used to inform guide efforts to mitigate AMR.

Key word

oral antibacterial agents, antimicrobial resistance, antimicrobial stewardship, outpatient

Received

September 26, 2019

Accepted

March 11, 2020

Jpn. J. Chemother. 68 (4): 532-538, 2020