Table 3

CRC ORsa and 95% CIs for NAT2 and NAT1 genotypes and CYP1A2 and NAT2 phenotypes

All genotyped subjectsPhenotyped subjects
NbOR (95% CI)NOR (95% CI)
NAT2 genotype
 Slow124.1571.076/1201.0
 Intermediate223/2701.1 (0.8–1.5)148.1891.3 (0.8–1.9)
 Rapid196.2271.1 (0.7–1.5)124/1571.2 (0.8–1.9)
P = 0.76cP = 0.51
NAT1 genotype
 Slow249/2681.0158.1931.0
 Intermediate189/2690.8 (0.6–1.0)127.1870.9 (0.6–1.2)
 Rapid101.1121.0 (0.7–1.4)60/830.8 (0.5–1.3)
P = 0.58P = 0.28
CYP1A2 phenotyped
 ≤3.48104/1561.0
 3.49–7.25112.1551.1 (0.7–1.6)
 >7.26133.1561.3 (0.9–1.8)
P = 0.22
NAT2 phenotypee
 ≤0.62104/1561.0
 0.63–1.56135.1551.4 (0.9–2.0)
 >1.57110.1561.0 (0.6–1.5)
P = 0.81
  • a Adjusted by unconditional logistic regression for age, sex, ethnicity, pack-years of cigarette smoking, lifetime recreational physical activity, lifetime aspirin use, body mass index 5 years ago, years of schooling, and intake of nonstarch polysaccharides from vegetables and calcium from foods and supplements. The model for CYP1A2 phenotype was also adjusted for the number of cigarettes, cigars, and pipes smoked during the 2 weeks preceding the caffeine test.

  • b Number of cases/number controls.

  • c P for trend based on a trend variable assigned 1, 2, or 3 for the slow, intermediate, and rapid genotype, respectively, or assigned the median for the appropriate phenotype category.

  • d As determined by the urinary ratio (17U + 17X):137X.

  • e As determined by the urinary ratio AFMU:1X.