Abstract:To investigate the preparation status and influencing factors of inadequate bowel preparation for colonoscopy in patients with ulcerative colitis (UC) and to formulate corresponding strategies, data from 207 UC patients who underwent colonoscopy at the Digestive Endoscopy Center of Changhai Hospital from January 2023 to March 2024 were retrospectively reviewed. Patients’ basic information, endoscopic examination reports, Boston bowel preparation scale (BBPS) scores, and follow-up outpatient information were extracted. Based on BBPS scores, patients were divided into an adequate bowel preparation group and an inadequate bowel preparation group. Logistic regression analysis was used to identify factors influencing inadequate bowel preparation. The results showed that the rate of inadequate bowel preparation was 9.2% (19/207). Combined with diabetes (P=0.013, OR=12.490, 95%CI:1.718-90.784), simple clinical colitis activity index (SCCAI) score for UC (P=0.029, OR=1.191, 95%CI:1.018-1.394), and use of biologics (P=0.029, OR=12.416, 95%CI:1.291-119.425) were significant influencing factors for inadequate bowel preparation. SCCAI score (r=-0.172, P=0.013), Mayo endoscopic score (r=-0.259,P<0.001), and lesion location (r=-0.217,P=0.002) were negatively correlated with BBPS score. In conclusion, the adequacy of bowel preparation during colonoscopy in UC patients still needs improvement. For patients with diabetes, those using biologics, and those with high SCCAI scores, a series of enhanced measures should be implemented to effectively reduce the rate of inadequate bowel preparation.