Do indication and demographics for colonoscopy affect completion? A large national database evaluation

Indication for colonoscopy has not been examined as a predictor of colonoscopy completion. We hypothesized that colonoscopy conducted for colorectal cancer screening might have higher in completion rates than colonoscopy conducted for other indications.

The study design was a retrospective cohort. Colonoscopies recorded within the Clinical Outcomes Research Initiative database conducted between 1 January 2002 and 30 June 2003 were analyzed. Indication included: average-risk screening; surveillance; nonspecific abdominal symptoms; bleeding symptoms; or family history of colorectal carcinoma. Demographic factors and indication for colonoscopy were evaluated for the outcome of incomplete colonoscopy using logistic regression analysis.

129 549 Colonoscopy procedures were analyzed. Average risk screening seemed to be protective for completion (relative risk: 0.69; 95% confidence interval: 0.63-0.75). Bleeding and nonspecific symptoms had higher risk of incomplete procedure compared to other indications. Males had higher completion rates compared to females (relative risk: 0.62; 95% confidence interval: 0.58-0.66). Community setting had higher completion rates compared to academic or Veteran's administration sites. Increasing age was associated with higher rate of incomplete colonoscopy.

Colonoscopy conducted for screening indication has comparable completion rates when compared with other indications. An overall completion rate of around 95% was noted in this study. This is the largest study to date verifying that completion rates are meeting recommended multisociety guidelines in the USA. Nonspecific abdominal symptoms in Caucasian population, female sex, advanced age, clinical setting, and ethnic groups African-American and Hispanic were found to have increased risk of incomplete procedure.