Table 2.

Main effects of NAT2 and NAT1*10 genotypes, meat intake, doneness preference, pack-years of smoking, and heterocyclic amine intake on colorectal cancer risk

Cases/controls
OR (95% CI)
Age-sex-ethnicity adjustedMultivariate adjusted
NAT2
Slow336/49711
    Intermediate414/6520.91 (0.75-1.10)0.92 (0.75-1.12)
    Rapid242/3440.96 (0.75-1.22)0.99 (0.77-1.27)
    P trend*0.650.83
NAT1
    No *10 allele362/52711
    One *10 allele307/5390.85 (0.70-1.05)0.86 (0.70-1.06)
    Two *10 allele175/2790.98 (0.77-1.26)1.01 (0.79-1.30)
    P trend0.660.83
Red meat intake (g/1,000 kcal/d)
    0 to <10.4238/38011
    10.4 to <17.7249/3811.04 (0.83-1.31)1.01 (0.80-1.28)
    17.7 to <26.0282/3811.22 (0.97-1.53)1.11 (0.88-1.41)
    26.0+240/3801.07 (0.84-1.35)0.96 (0.74-1.23)
    P trend0.340.67
Processed meat intake (g/1,000 kcal/d)
    0 to <3.5222/38011
    3.5 to <6.7250/3811.11 (0.88-1.40)1.04 (0.82-1.32)
    6.7 to <11.0274/3811.25 (0.99-1.57)1.13 (0.89-1.44)
    110.+263/3801.23 (0.97-1.56)1.08 (0.83-1.39)
    P trend0.050.46
Meat and fat pattern (factor score)
    Quartile 1221/38011
    Quartile 2248/3811.10 (0.87-1.40)1.03 (0.81-1.31)
    Quartile 3269/3811.25 (0.99-1.58)1.11 (0.87-1.43)
    Quartile 4271/3801.33 (1.04-1.70)1.13 (0.86-1.47)
    P trend0.010.32
Doneness pref.
    Medium/rare510/77211
    Well done492/7381.03 (0.87-1.22)1.07 (0.90-1.28)
    P0.760.43
Pack-years of smoking
    0364/67411
    >0 to <30461/6481.38 (1.15-1.66)1.34 (1.11-1.62)
    30+184/2001.66 (1.29-2.13)1.51 (1.17-1.95)
    P trend<0.00010.0004
Total HCA (ng/1,000 kcal/d)
    0 to <217.3131/48111
    217.3 to <566.9146/4821.17 (0.89-1.54)1.15 (0.87-1.53)
    566.9+121/4811.09 (0.81-1.45)1.03 (0.77-1.39)
    P trend0.550.82
DiMeIQx (ng/1,000 kcal/d)
    0 to <1.8119/48111
    1.8 to <6.2147/4821.29 (0.97-1.70)1.25 (0.94-1.67)
    6.2+132/4811.24 (0.93-1.66)1.18 (0.88-1.59)
    P trend0.140.28
MeIQx (ng/1,000 kcal/d)
    0 to <29.8126/48111
    29.8 to <93.5141/4821.14 (0.86-1.50)1.05 (0.79-1.40)
    93.5+131/4811.19 (0.89-1.58)1.09 (0.81-1.47)
    P trend0.230.57
PhIP (ng/1,000 kcal/d)
    0 to <171.1134/48111
    171.1 to <460.5144/4821.12 (0.85-1.47)1.11 (0.84-1.47)
    460.5+120/4811.06 (0.79-1.41)1.03 (0.77-1.39)
    P trend0.690.81
  • NOTE: Number of cases and controls, odds ratios. Odds ratios were calculated by using logistic regression and adjusted for sex, age at blood draw, and ethnicity (age-sex-ethnicity adjusted) or with additional adjusted for family history of colorectal cancer, body mass index, intake (per 1,000 kcal/d) of dietary fiber, calcium, vitamin D, folic acid, ethanol, physical activity (metabolic equivalents), smoking status and pack-years of smoking, or meat intake, as appropriate (multivariate adjusted).

    Abbreviations: OR, odds ratio; pref., preference.

  • * P for trend is based on Wald test for variable coded as 1 to 3.