key: cord-0776135-z0crpwqf
authors: KWOK, Kin On; WEI, Wan In; MA, Bosco Hon Ming; IP, Margaret; CHEUNG, Heidi; HUI, Elsie; TANG, Arthur; MCNEIL, Edward; WONG, Samuel Yeung Shan; YEOH, Eng Kiong
title: Antibiotic use among COVID-19 patients in Hong Kong, January 2018 to March 2021
date: 2022-02-17
journal: J Infect
DOI: 10.1016/j.jinf.2022.02.014
sha: fbad84dbf81a52ce41ba109dfe417e3b2afffcc3
doc_id: 776135
cord_uid: z0crpwqf

nan

the authors attributed their low prevalence of antibiotic use to their national antimicrobial stewardship initiatives. However, caution should be exercised when interpreting such reported rates of antibiotic use because they are dependent on the types of SARS-CoV-2 patients who were hospitalized. In addition, to further unravel the impact of the COVID-19 pandemic on antibiotic prescribing, it is useful to compare the antibiotic use in the community in the prepandemic period and that in the peri-pandemic period. To this end, we report the dispensing pattern of antibiotics in public hospitals for managing COVID-19 cases and compares the change of antibiotic use by such cases in general outpatient settings unrelated to COVID-19 from 2018 to 2020 in Hong Kong.

In this study, inpatient records of COVID-19 cases admitted to hospitals affiliated with the Hospital Authority were retrieved up to 3 March 2021. Pharmacy dispensing records of general outpatient settings for this cohort was available from 2018 onwards. Inpatient antibiotic use was expressed as defined daily doses (DDD)/ days of therapy (DOT) per 1000 bed-days.

Outpatient antibiotic use was expressed as DDD per 100000 person-days, where each case's person-day contribution was assumed as 365 days in 2018 and 2019, and as the number of days prior to their diagnosis of COVID-19 in 2020. Co-infections alongside COVID-19, based on ICD-9 discharge diagnoses and empiric classification of physicians, were grouped into bacterial or others. More methodological details is in Appendix I.

As of 3 March 2021, there were 11047 laboratory-confirmed COVID-19 cases in Hong Kong, of which 11004 were hospitalized and were included in the analysis. The mean (SD) age at hospital admission was 44.7 (19.9) years, with 8.2% of cases aged <18 years. Patient characteristics are summarized in Table S1 . Antibiotic use was 251.0 DOT per 1000 bed-days and 289.7 DDD per 1000 bed-days among 10106 adult cases. There were 29.1% of cases treated with antibiotics, but only 1.84% had confirmed bacterial co-infections. Of the overall antibiotic use, 6.1% was prescribed to cases with bacterial co-infections (confirmed: 9.6 DDD per 1000 bed-days; presumed: 8.1 DDD per 1000 bed-days) ( Table 1) . Antibiotic use was common in cases without any co-infections (66.1%, 191.4 DDD per 1000 bed-days) or when the cocondition was uncertain (13.7%, 39.8 DDD per 1000 bed-days). Almost all inpatient antibiotic use fell into the WHO's AWaRe classification list (access:54.6%; watch:42.0%; reserve:1.16%) ( Figure 1 ). Cefoperazone/sulbactam, and ticarcillin/tazobactam, which are not recommended by WHO for clinical use, were also prescribed. In general outpatient settings from 2018 to 2020, community antibiotic use dropped from 52.8 to 45.9 DDD per 100000 person-days (Table S2) .

This decreasing trend was also observed for individual antibiotics, except for amoxicillin/clavulanic acid, the use of which increased from 25.9 to 29.3 DDD per 100000 person-days.

With data from the same individuals prior to and amid the pandemic, we draw inferences based on a self-controlled case series method that eliminates all time-invariant confounding [4].

Our results have three public health implications.

First, this study adds to the literature with the rate of antibiotic use in a complete cohort of cases, which is more adaptable to regions with low prevalence of COVID-19. In Hong Kong, the number of cases was low such that hospitalization can be used as an isolation strategy (i.e. all cases were hospitalized). With the inclusion of mild and asymptomatic cases, it is not surprising that our reported rate is lower than that of other countries (74.6% This study has two limitations. First, we assumed that antibiotics prescribed in the public outpatient settings are unrelated to COVID-19. Though cases, before diagnosis, might have obtained antibiotics for COVID-19 from public outpatient settings, this possibility was minimal because of the intense contact-tracing (and the following quarantine) in place and that hospitalization was the isolation strategy such that treatment of COVID-19 should predominantly take place in hospitals. Second, we only had data from the public healthcare sector such that a complete description of antibiotic use in the community is limited by the lack of data from the private healthcare sector. 

Survey of antibiotic and antifungal prescribing in patients with suspected and confirmed COVID-19 in Scottish hospitals

Antibiotic prescribing in patients with COVID-19: rapid review and meta-analysis

Antibiotics in treatment of COVID-19 complications: a review of frequency, indications, and efficacy

Self controlled case series methods: an alternative to standard epidemiological study designs

Co-infections in people with COVID-19: a systematic review and meta-analysis

Bacterial co-infection and secondary infection in patients with COVID-19: a living rapid review and meta-analysis

Community Antibiotic Use at the Population Level During the SARS-CoV-2 Pandemic in British Columbia

Epidemiology, clinical spectrum, viral kinetics and impact of COVID-19 in the Asia-Pacific region