摘要：The association between bowel habits and colorectal neoplasms was studied in a case-control study involving 520 cases with colorectal adenoma, 217 cases with colorectal cancer, 638 hospital controls without no endoscopical findings in the large intestine and 577 population controls. Compared with population controls, the relative risk (RR) for soft stools were in-creased for every site of colorectal adenoma and cancer and that for hard stools was increased for colon adenoma and cancer. However, these associations were not observed with hospital controls. The RRs for rectal and distal colon adenomas and rectal cancer, compared with either control group, progressively increased with increasing the number of bowel movements.The RR for two or more bowel movements per day, adjusted for other confounding factors, was 2.11 (95% confidence interval (CI): 1.24-3.60) for distal colon adenoma, 3.52 (95% CI : 1.56-7.93) for rectal adenoma and 7.72 (95% Cl : 3.18-18.76) for rectal cancer, compared with hospital controls. All of the associations are not likely to be explained by effects of disease. These results suggest that bowel habits indicating diarrhea and underlying inflammation may increase the risk of neoplasms in the distal colon and rectum. J Epidemiol, 1993; 3 : 1-5.
