Mo1200 Demographic and Behavioural Predictors of Ongoing Adherence to Faecal Occult Blood Test Screening for Colorectal Cancer

Abstract

cancers as those diagnosed in patients with colonoscopy between 6-36 months previously, and all others to have detected cancers. The presence of diverticulosis was identified through diagnosis codes during the previous three years. We compared the prevalence of diverticulosis in interval and detected cancers according to tumor location. The independent association of diverticulosis was then evaluated in a logistic model with generalized estimating equations accounting for clustering by endoscopists and stratified by tumor location. The model adjusted for demographics, comorbidity and endoscopist characteristics. Results: We identified 57,839 patients, including 53,647 with detected cancers and 4,192 (7.2%) with interval cancers. A previous diagnosis of diverticulosis was documented in 69.3% of interval cancers and 26.9% of detected cancers (p,0.001). In all segments of the colon, the prevalence of a diverticulosis diagnosis was higher in interval cancers than in detected cancers (Table) (p,0.001 for all comparisons). In the multivariable analysis, diverticulosis was strongly associated with interval cancer risk in both the proximal colon (cecum to splenic flexure) (Adjusted Odds Ratio (AOR) 5.43, 95% CI 4.98-5.93) and distal colon (descending, sigmoid) (AOR 6.59, CI 5.65-7.69). Conclusions: A previous diagnosis of diverticulosis is a strong risk factor for interval colon cancer regardless of tumor location. Given the greater prevalence and extent of diverticulosis in the left colon, it suggests that factors other than impaired visualization of neoplasia between diverticuli are involved in the pathogenesis of interval cancer. Prevalence of Diverticulosis