Table 4

Joint effects of CYP2E1, PM, and fruit and vegetable intake on CRC risk

SubsiteCYP2E1Intakes (g/day) of fruits and vegetables and PMsa
High F&V, low PMLow F&V, high PMPd
nbORc (95% CI)nOR (95% CI)
ColonRsaI c1/c1 35/1141.086/1182.3 (1.4–3.9)
Any c220/491.5 (0.8–3.1)20/451.4 (0.7–2.9)0.05
Insert 0 38/1171.080/1231.9 (1.2–3.1)
1 or 216/441.3 (0.6–2.6)26/402.1 (1.0–4.0)0.69
RectumRsaI c1/c1 19/1141.046/1182.3 (1.2–4.4)
Any c27/491.0 (0.4–2.9)14/451.7 (0.7–3.9)0.60
Insert 0 18/1171.032/1231.7 (0.8–3.3)
1 or 28/441.6 (0.6–4.3)28/405.0 (2.2–11.4)0.27
  • a High F&V, low PM, fruit and vegetable intake > median (684 g/day) and PM intake ≤ median (14.8 g/day). Low F&V, high PM, fruit and vegetables intake ≤ median and processed meat intake > median.

  • b No. of cases/no. of controls.

  • c ORs (and 95% CIs) adjusted by unconditional logistic regression for age, sex, ethnicity, pack-years of cigarette smoking, lifetime recreational physical activity (hours), lifetime aspirin use (months), body mass index 5 years ago, years of schooling, and intake of calcium from foods and supplements.

  • d P for interaction based on the likelihood ratio test comparing the model with interaction with one containing only main effects for the two variables (test has 1 degree of freedom).