Table 6

Combined effect of GSTM-1 genotype and NAT2-imputed phenotype and cigarette smoking on rectal cancer risk in men

GST present NAT2 slow n (case/control)GST present NAT2 rapid n (case/control)GST null NAT2 slow n (case/control)GST null NAT2 rapid n (case/control)
Cigarette smoking status
 Never46/7233/4944/7041/54
 Former62/5740/5350/7135/51
 Current (<5 yr)22/1915/2322/1538/22
OR (95% CI)aOR (95% CI)OR (95% CI)OR (95% CI)
 Never1.01.2 (0.6–2.1)1.1 (0.6–1.8)1.3 (0.7–2.3)
 Former1.9 (1.1–3.2)1.3 (0.7–2.3)1.2 (0.7–3.0)1.1 (0.6–2.1)
 Current (<5 yr)1.9 (0.9–3.9)1.0 (0.5–2.2)2.3 (1.1–5.0)2.5 (1.3–4.8)
  • a Adjusted for age, physical activity level, alcohol intake, and body size.