Predictors of inadequate bowel cleansing in colon capsule endoscopy: a single-center retrospective study

the rate of adequate bowel preparation and complete examinations are crucial quality measures in colon capsule endoscopy (CCE). The aim of this study was to evaluate clinical and demographic factors possibly associated with inadequate bowel preparation in patients undergoing CCE.

retrospective cross-sectional study including consecutive patients submitted to CCE between September 2019 and August 2021. The primary outcome was the adequacy of bowel preparation, using the Colon Capsule CLEansing Assessment and Report (CC-CLEAR). Secondary outcomes included the rate of complete examinations and the presence of findings throughout the colon.

a total of 202 patients were included, 140 (69.3 %) with adequate bowel preparation and 62 patients (30.7 %) with inadequate bowel preparation. Patients with diabetes mellitus or hypothyroidism were more likely to have inadequate bowel preparation (OR 2.247, 95 % CI: 1.115-4.525, p = 0.022, and OR 3.226, 95 % CI: 1.143-9.091, p = 0.044, respectively), as well as smokers and patients on psychotropic drugs, namely benzodiazepines and/or antidepressants (OR 3.115, 95 % CI: 1.381-7.042, p = 0.005, and OR 1.916, 95 % CI: 1.041-3.521, p = 0.036, respectively). The adequacy of bowel preparation was not associated with the detection of findings (right p = 0.928, transverse p = 0.967 and left colon p = 0.632), similarly to the rate of complete examinations (p = 0.100). According to multivariable analysis, diabetes mellitus (OR 2.451, 95 % CI: 1.153-5.208, p = 0.020), hypothyroidism (OR 3.269, 95 % CI: 1.095-9.755, p = 0.034), smoking (OR 4.115, 95 % CI: 1.721-9.840, p = 0.001) and being on psychotropic drugs (OR 2.344, 95 % CI: 1.200-4.577, p = 0.013) were independent predictive factors for inadequate bowel preparation.

diabetes mellitus, hypothyroidism, active smoking and the use of psychotropic drugs were identified as predictors of inadequate bowel preparation in CCE. In such patients, the bowel preparation regimen should be optimized to enhance the quality and diagnostic yield of CCE.