Lack of Association between Red Meat Consumption and a Positive Fecal Immunochemical Colorectal Cancer Screening Test in Khon Kaen, Thailand: a Population- Based Randomized Controlled Trial.

Background: There is convincing evidence from epidemiological studies that meat consumption increases colorectal cancer (CRC) risk. However, assessment of any association with a positive fecal immunochemical test (FIT) in CRC screening has been limited. If a link could be shown this might be helpful for establishing a risk group for colonoscopy. Objective: This study aimed to assess any association between meat consumption and other lifestyle factors and a positive FIT result in a Thai population. Methods: A cross-sectional analytical study was conducted with 1,167 participants in a population-based randomized controlled trial. CRC was screened from May 2016 - February 2017. Subjects aged 45-74 years who met the eligibility criteria were randomly allocated to the study arm. A positive FIT was determined with cut-off 100 ng/mL. Multiple logistic regression was used to analyze any relationship between lifestyle factors and a positive FIT. Result: The total number of subjects was 1,060 (90.8% return rate of FIT). With FIT100, FIT150, and FIT200, positive tests were found in 92 (8.68%), 74 (6.98%), and 60 (5.66%), respectively. No significant associations were noted with any of the variables, except for being aged 60-74 years (ORadj = 1.62, 95% CI: 1.03-2.54) Borderline significance was observed for high consumption of vegetables (ORadj = 0.62, 95% CI: 0.36-1.07) and being male (ORadj = 1.39, 95% CI: 0.87-2.22). Conclusion: Despite the evidence from the literature, no association was here found between a positive FIT result and meat consumption or other well-established lifestyle parameters. Being aged 60-74 years was a risk factor which should be taken into account in CRC screening strategy in countries like Thailand with limited access to endoscopy.