Predictors of advanced colorectal neoplasia at initial and surveillance colonoscopy after positive screening immunochemical faecal occult blood test.

BACKGROUND

Characteristics such as gender and lifestyle are not taken in account in colorectal cancer screening and surveillance recommendations.

AIMS

To identify factors associated with advanced neoplasia at initial and surveillance colonoscopy.

METHODS

In this observational study, 750 individuals with positive faecal occult blood test, aged 50-74 years, underwent a first screening colonoscopy in 2007-2009. We collected anthropometric data as well as data on physical activity, smoking and drinking habits, fruit and vegetable consumption and low-dose aspirin use through a questionnaire.

RESULTS

At initial colonoscopy advanced neoplasia (n=399, 53.2%) was positively associated with age, male gender, smoking and alcohol drinking, and inversely associated with physical activity, fruit and vegetables consumption and long-term use of aspirin. These 7 factors were used to calculate a risk score, ranging from 0 (no unfavourable characteristics) to 7 (all unfavourable characteristics present), which was significantly associated with advanced neoplasia (odds ratio 1.55 for one point increase, P<0.01). Among the 372 adenoma patients who returned for follow-up surveillance colonoscopy, the score remained associated with advanced neoplasia (odds ratio 1.28 for one point increase, P=0.01).

CONCLUSION

Besides age and gender, modifiable factors such as lifestyle and aspirin use were associated with the risk of advanced neoplasia at initial and surveillance colonoscopy.