Tu1179 Colorectal Cancer Screening Program in the Ontario Population: the Additional Effects of Identifying Individuals With an Increased Risk

The analysis was limited to patients who survived at least 5 years and patients were censored at the time of the next colonoscopy or five years after the index procedure. Factors predictive of repeat colonoscopy were examined with univariate analysis and a multivariable logistic model was used to determine predictors of repeat colonoscopy within five years. Results: A total of 7,507 patients were included in the study. Through the end of the five year follow up, 33.3% received another colonoscopy and 24.2% underwent repeat polypectomy. FOBT, flexible sigmoidoscopy and barium enema were performed in 34.8%, 3.9% and 3.1%, respectively. We observed a marked decrease in repeat colonoscopy at 1, 3 and 5 years with more recent years of index procedures (Table). Other predictors of undergoing repeat colonoscopy were younger age, lower comorbidity score, colonoscopy within 5 years prior to the index procedure, and a previous diagnosis of IBD or carcinoma in situ. There was no clinically significant association with physician specialty, geographic location or small area socioeconomic variables. The decreasing use of colonoscopy with time was maintained in a multivariable analysis (multivariable odds ratio (OR) 2002: 0.81, 95% CI 0.74-0.90; OR 2003: 0.72, 95% CI 0.65-0.80; OR 0.59, 95% CI 0.53-0.66). Conclusions: In this population-based sample, we have documented underuse of follow up colonoscopy at 5 years after polypectomy. In particular, the use of this procedure has decreased over the four-year study period. Coupled with other data showing overuse of follow up colonoscopy in patients without resected polyps, the findings suggest significant discordance between guidelines and actual practice.