Table 4.

Odds ratios and 95% confidence intervals of cigarette smoking for hyperplastic and adenomatous polyps of the distal colon and rectum by morphological characteristics and subsite of the descending colon, sigmoid colon, and rectum (Prostate, Lung, Colorectal, and Ovarian Trial, 1993-2000)

Ex smokers
Current smokers
Hyperplastic polyps
Adenomatous polyps
Hyperplastic polyps
Adenomatous polyps
CasesOR (95% CI)CasesOR (95% CI)CasesOR (95% CI)CasesOR (95% CI)
Single/multiple
    Single4721.6 (1.4-1.9)7711.1 (1.0-1.2)1533.3 (2.7-4.1)1901.6 (1.3-1.9)
    Multiple2902.3 (1.9-2.9)2971.2 (1.0-1.5)1256.2 (4.7-8.0)852.2 (1.7-2.9)
Size (cm in diameter)
    Small (<1 cm)5471.6 (1.4-1.9)6361.0 (0.9-1.2)1793.3 (2.7-4.0)1511.5 (1.3-1.9)
    Large (≥1 cm)452.3 (1.3-4.1)3271.2 (1.0-1.5)134.0 (1.9-8.5)912.0 (1.5-2.5)
Villous
    No8341.1 (1.0-1.2)2221.8 (1.5-2.1)
    Yes2341.2 (0.9-1.4)531.5 (1.1-2.1)
Subsite of distal colorectum*
    Descending and sigmoid colon4911.7 (1.5-2.0)8541.1 (1.0-1.3)2084.6 (3.8-5.6)2321.9 (1.6-2.2)
    Rectum3502.1 (1.7-2.5)3041.1 (0.9-1.3)1124.2 (3.2-5.4)721.5 (1.2-2.0)
  • NOTE: ORs compared with never tobacco users and adjusted for age, sex, education, fruit, alcohol intake, cigarettes smoked per day, and study centers.

    Abbreviations: OR, odds ratio; 95% CI, 95% confidence interval.

  • * Adenomas with multiple sites of the descending colon, sigmoid colon, and rectum were not included.