Table 5.

Association between meat and HCA intake levels and colorectal polyp risk stratified by combination of risk genotypes of the AhR and NAT1 genes on colorectal polyp risk, the TCPS, 2003-2005

GenotypesIntakePolyp type
Adenomatous only
Hyperplastic only
Concurrent adenomatous and hyperplastic
OR (95% CI)*PintOR (95% CI)*PintOR (95% CI)*Pint
Low riskTotal meat0.98 (0.93-1.04)1.03 (0.95-1.12)0.94 (0.86-1.02)
Red meat1.02 (0.96-1.08)1.04 (0.96-1.14)0.99 (0.91-1.09)
MeIQx1.01 (0.95-1.07)1.03 (0.95-1.12)1.00 (0.91-1.09)
PhIP0.99 (0.93-1.04)1.05 (0.97-1.13)0.97 (0.90-1.06)
DiMeIQx0.98 (0.93-1.04)1.05 (0.97-1.13)1.01 (0.93-1.10)
BaP1.02 (0.96-1.07)1.05 (0.98-1.14)0.97 (0.89-1.05)
Mutagenic activity0.98 (0.93-1.04)1.02 (0.95-1.10)0.98 (0.90-1.06)
Intermediate riskTotal meat0.99 (0.93-1.06)1.05 (0.97-1.13)1.10 (0.99-1.21)
Red meat0.99 (0.93-1.06)1.00 (0.92-1.09)1.11 (1.00-1.23)
MeIQx0.98 (0.92-1.04)1.04 (0.96-1.13)1.06 (0.96-1.17)
PhIP1.02 (0.97-1.08)1.04 (0.97-1.13)1.02 (0.93-1.12)
DiMeIQx1.01 (0.95-1.07)1.05 (0.97-1.14)1.05 (0.96-1.15)
BaP0.97 (0.91-1.03)1.03 (0.95-1.12)1.02 (0.92-1.12)
Mutagenic activity0.99 (0.93-1.05)1.03 (0.96-1.12)1.05 (0.95-1.15)
High riskTotal meat1.09 (0.98-1.21)0.6991.25 (1.03-1.51)0.4331.57 (1.23-2.01)0.019
Red meat1.15 (1.02-1.30)0.4721.31 (1.06-1.63)0.2751.60 (1.23-2.09)0.023
MeIQx1.06 (0.94-1.19)0.6341.12 (0.92-1.35)0.9571.48 (1.14-1.92)0.048
PhIP1.01 (0.91-1.12)0.7661.13 (0.94-1.34)0.9401.39 (1.11-1.74)0.055
DiMeIQx1.04 (0.93-1.15)0.9341.14 (0.95-1.36)0.9971.37 (1.10-1.71)0.115
BaP1.08 (0.97-1.22)0.3841.17 (0.97-1.41)0.5691.26 (1.02-1.54)0.323
Mutagenic activity1.04 (0.94-1.15)0.9811.13 (0.95-1.35)0.9431.31 (1.08-1.60)0.079
  • * ORs were estimated for a 10% increment of intake and adjusted for age, sex, study site, educational attainment, indication for colonoscopy, smoking, alcohol consumption, physical activity, and regular NSAID use.

  • P values for interactions of dietary exposure and genotype were derived from log-likelihood ratio test.

  • Defined as “low-risk” genotypes AhR GG or NAT1 slow or intermediate acetylator, “intermediate-risk” genotypes AhR GG or NAT1 rapid acetylator or AhR GA/AA or NAT1 slow or intermediate acetylator, and “high-risk” genotypes AhR GA/AA or NAT1 rapid acetylator.