Background: Patients are referred for colonoscopy for symptom assessment, screening, and surveillance. Public health measures to mitigate the spread of the COVID−19 pandemic disrupted services and increased patient delays for colonoscopy services in Quebec. The differential impact of these interruptions by colonoscopy indication is largely unknown. Methods: Using 2018−2022 retrospective clinical data from two high-volume Montreal endoscopy centres and provincial administrative data, we characterized changes in colonoscopy wait times and the proportion of waitlisted patients who were delayed (wait time exceeded provincial guidelines) by procedure indication and demographics. We used regression to examine patient characteristics associated with delayed procedures during pre- and intra−COVID−19 periods. We used time series analysis to characterize trends in the proportion of waitlisted patients delayed. Results: The COVID-19−related public health measures resulted in record-high delays (median increase in wait times of 34−159% across indications). While older patients experienced longer wait times pre-pandemic, intra−COVID−19 wait times increased disproportionately for patients younger than 50. The proportion of waitlisted patients delayed peaked mid−2020 (56.9% for screening; 56.0% for symptom assessment patients). By early 2022, the proportion delayed had fallen to 37.3% for screening patients but remained at 53.8% for symptom assessment patients. Conclusions: In Quebec, intra-COVID-19 colonoscopy delays disproportionately impacted symptom assessment procedures and younger patients. Additional capacity or improved triaging may be needed to address persistent delays. Understanding the effects of the pandemic on colonoscopy services can help inform strategies to mitigate harms from on-going delays in Quebec.

The authors have declared no competing interest.

This study did not receive any funding.

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The Research Ethics Board of the McGill University Health Centre gave ethical approval for this work.

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