Impact of the COVID-19 Pandemic on Hospital Antimicrobial Purchasing in Canada (2018-2021): An Exploratory Analysis

The impact of the COVID-19 pandemic on antimicrobial use in Canadian hospitals is not well characterized. We explored the relationship between the COVID-19 pandemic and Canadian hospital antimicrobial purchasing (AMP)-a proxy for consumption.

Hospital-level AMP data were obtained from IQVIA, a health analytics company, and matched with inpatient patient-day denominator data from 28 hospitals participating in the Canadian Nosocomial Infection Surveillance Program. Monthly AMP was measured using defined daily doses (DDDs) per 1,000 patient-days. Segmented linear regression with hospital-level clustering assessed for step and slope changes in AMP between pre-pandemic (January 1, 2018 - February 29, 2020) and pandemic (March 1, 2020 - December 31, 2021) periods.

Although we found an initial increase in AMP with the onset of the pandemic (+42 DDDs/1,000 patient-days [pd]) followed by a decreasing trend in AMP during the pandemic (-5 DDDs/1,000 pd per month), neither was statistically significant. Changes in trends varied across antimicrobial classes/subclasses, with decreases in broad-spectrum penicillins (-2 DDDs/1,000 pd per month, p < .001) and macrolides/lincosamides (-2 DDDs/1,000 pd per month, p < .001) and an increase in carbapenems (1 DDD/1,000 pd per month, p < .001). These results coincided with decreases in piperacillin/tazobactam (p = .003) and azithromycin (p = .001) and an increase in meropenem (p < .001).

We observed a transient increase in overall AMP with the onset of the pandemic (March 2020) in this exploratory analysis of a sample of 28 hospitals. Changes in trends varied by antimicrobial class/subclass and individual agent. Further work is needed to discern contributors to these trends, such as changes in inpatient characteristics and treatment guidelines.