Longer withdrawal time is not associated with increased patient discomfort in colonoscopy: a retrospective observational study

PURPOSE: Withdrawal time of sufficient length is a quality indicator for colonoscopies. Nonetheless, whether extending the withdrawal time contributes to patient discomfort remains unknown. This study aimed to clarify the relationship between colonoscopy withdrawal time and patient discomfort. METHODS: A cohort of consecutive patients who underwent colonoscopy at a single institution from October 2018 to January 2020 was retrospectively analyzed. Initially, the relationship between the mean withdrawal time for each colonoscopist in no-finding examinations and polyp detection rate was investigated in 2,043 patients. Subsequently, the primary outcome of association between withdrawal time and patient discomfort, as determined by patient questionnaire, was assessed for each examination in 481 patients from the initial cohort. RESULTS: The mean withdrawal time was strongly correlated with polyp detection rate (correlation coefficient, 0.72; P<0.001). In contrast, longer withdrawal time was not associated with increased discomfort; however, there was a weak inverse correlation between patient discomfort and longer withdrawal time (correlation coefficient, –0.25; P<0.001). Similarly, multiple regression analysis adjusted for confounding variables revealed that longer withdrawal time was not associated with increased patient discomfort (regression coefficient, –0.04 for each 1-minute increase in the length of withdrawal time; P=0.45). CONCLUSION: This study showed for the first time that longer withdrawal times did not result in increased discomfort, indicating that withdrawal time can be extended to sufficient length for optimal patient examination and polyp detection.