Vol.73 No.3 May 2025

Antimicrobial use in outpatients: A multicenter study using the Japan Surveillance for Infection Prevention and Healthcare Epidemiology (J-SIPHE) data

Hiroko Hashimoto¹⁾, Mio Endo¹⁾, Sanae Suzuki¹⁾, Taichi Tajima¹⁾, Takashi Niwa²⁾, Hisashi Baba³⁾, Kazunori Yamada⁴⁾, Kenji Kamiyama⁵⁾, Minoru Sakurada⁶⁾, Yoshiyuki Sakai⁷⁾, Keisuke Kagami⁸⁾, Nobuhisa Ishiguro⁹⁾, Shinya Tsuzuki^{1, 10)}, Nobuaki Matsunaga¹⁾, Kayoko Hayakawa^{1, 10)} and Norio Ohmagari^{1, 10)}

¹⁾AMR Clinical Reference Center Disease Control and Prevention Center, National Center for Global Health and Medicine, 1-21-1 Toyama, Shinjuku-ku, Tokyo, Japan
²⁾Department of Pharmacy, Gifu University Hospital
³⁾Division of Infection Control, Gifu University Hospital
⁴⁾Department of Pharmacy, Nakamura Memorial Hospital
⁵⁾Department of Neurosurgery, Nakamura Memorial Hospital
⁶⁾Department of Pharmacy, Hakodate Municipal Hospital
⁷⁾Department of Pediatrics, Hakodate Municipal Hospital
⁸⁾Department of Pharmacy, Hokkaido University Hospital
⁹⁾Department of Infection Control and Prevention, Hokkaido University Hospital
¹⁰⁾Disease Control and Prevention Center, National Center for Global Health and Medicine

Abstract

Although antimicrobials used in hospitals are also frequently prescribed to outpatients, there is currently no clear indicator for multicenter evaluation of antimicrobial use in outpatients. In this study, we investigated an index to evaluate the status of antimicrobial prescribing in outpatients and used data from five facilities in the Japan Surveillance for Infection Prevention and Healthcare Epidemiology (J-SIPHE) dataset to see if comparisons could be made among facilities. For the five-year period between January 2016 and December 2020, the number of outpatients, number of outpatients with prescriptions, the prescribed doses of antimicrobials, the prescribed duration of antimicrobial use, the number of patients prescribed antimicrobials, and the number of antimicrobial prescriptions were counted using insurance claims data (the combined E and F files for Outpatients). The median discrepancy between the number of outpatients as calculated from insurance claims data and the number of outpatients as defined by the Ministry of Health, Labour and Welfare in its hospital reports was 2.03, 8.50, and 13.89% at three facilities, although the rate at one facility was as high as 24.31%. As compared with prescriptions written during clinic hours, which ranged from 4.83 to 19.30 days, the number of days on which oral antimicrobials are prescribed outside of office hours was smaller, ranging from 1.80 to 6.00 days.
There were also differences in the class of antimicrobials prescribed. The overall data suggested that the discrepancies among facilities was greater for outpatient antimicrobials than for inpatient antimicrobials, due to the addition of multiple factors, such as dental treatment and medical treatment paid for by out of pocket expenses not covered by insurance claims information and differences among facilities outside of office hours. Our findings suggested that the registration data of J-SIPHE, which has a unified data source, could be used to understand and compare the status of antimicrobial use among facilities, although this would be based on the status of recording of the insurance claims data at each facility.

Key word

J-SIPHE, outpatient, antimicrobial, surveillance

Received

November 18, 2024

Accepted

February 4, 2025

Jpn. J. Chemother. 73 (3): 295-302, 2025