Time from Positive Screening Fecal Occult Blood Test to Colonoscopy and Risk of Neoplasia

There is no guideline defining the optimal time from a positive screening fecal occult blood test to follow-up colonoscopy. We reviewed records of 231 consecutive primary care patients who received a colonoscopy within 18 months of a positive fecal occult blood test. We examined the relationship between time to colonoscopy and risk of neoplasia on colonoscopy using a logistic regression analysis adjusting for potential confounders such as age, race, and gender. The mean time to colonoscopy was 236 days. Longer time to colonoscopy (OR = 1.10, P = 0.01) and older age (OR 1.04, P = 0.01) were associated with higher odds of neoplasia. The association of time with advanced neoplasia was positive, but not statistically significant (OR 1.07, P = 0.14). In this study, a longer interval to colonoscopy after fecal occult blood test was associated with an increased risk of neoplasia. Determining the optimal interval for follow-up is desirable and will require larger studies.