Prevalence of colorectal adenomatous polyps in patients with chronic obstructive pulmonary disease.

Background: Colorectal adenomatous polyps are precancerous lesions of colorectal cancer. The aim of this study was to assess the prevalence of colorectal adenomatous polyps in chronic obstructive pulmonary disease (COPD) patients and determine whether COPD is associated with colorectal malignant potential.

Methods: Subjects who had undergone post-bronchodilator spirometry and colonoscopy and were 40 years or older were selected from the hospital database. COPD was defined as a spirometry in which the ratio of forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC) is <0.7 in post-bronchodilator spirometry. The non-COPD group was matched for both age and sex, and were defined as having an FEV1, FVC, and FEV1/FVC ≥0.7 in spirometry. Finally, 333 patients were retrospectively reviewed; of this group, 82 patients had COPD.

Results: Among the subjects, 201 patients (60%) were nonsmokers, while 78 (23%) were current smokers. The prevalence of colorectal adenomatous polyps was 39% (98/251) in the non-COPD group and 66% (54/82) in the COPD group. Among 54 patients with adenomatous polyps in the COPD group, 47 had tubular adenoma and seven had villous adenoma. Multiple logistic regression analyses revealed that only COPD patients whom matched to the criteria of COPD by pulmonary function test (odds ratio 2.1, 95% confidence interval: 1.1-3.8; P=0.019) were independently associated with colorectal malignant potential.

Conclusion: The risk of colorectal malignant potential in the COPD group was higher than in the non-COPD group. We may suggest that COPD patients should consider regular colonoscopic evaluation to screen for premalignant colon polyps regardless of smoking.