Cigarette smoking, alcohol use, and colorectal adenoma in Japanese men and women.
OBJECTIVE
The aim of this study was to examine the relationships between smoking and alcohol use and risk of colorectal adenoma.


METHODS
Information about smoking, alcohol use, and other lifestyle variables were obtained prospectively from 14,427 male and 17,125 female residents in a city of Gifu Prefecture, Japan, by a self-administered questionnaire in September, 1992. Colorectal adenomas were newly diagnosed in 181 men and 78 women in this cohort between January, 1993 and December, 1995 by colonoscopic examination at two major hospitals of the city. Gender-specific and site-specific relative risks and 95 percent confidence intervals adjusted for age and for age plus other potential confounding factors were calculated by using logistic regression models.


RESULTS
Thirty or more years of smoking was significantly associated with risk of adenoma in general compared with never having smoked in both men and women (relative risk, 1.60; 95 percent confidence interval, 1.02-2.62 and relative risk, 4.54; 95 percent confidence interval, 2.04-9.08, respectively). Effect of smoking was stronger in the proximal colon. After adjusting for age and carbohydrate intake, total alcohol intake was not associated with risk of adenoma in any site in the colon in men. Sake drinkers were at significantly increased risk of adenoma in general, but the dose-response relationship was not statistically significant. Risk of adenoma in the rectum was not significantly increased for those who consumed >30.3 g/day of ethanol (relative risk, 5.7).


CONCLUSIONS
These data suggest that smoking is a risk factor of adenoma in Japanese men and women. The role of alcohol, however, is less clear.
Nagata
C
C
Department of Public Health, Gifu University School of Medicine, Japan.
Shimizu
H
H
Kametani
M
M
Takeyama
N
N
Ohnuma
T
T
Matsushita
S
S
D000236:Adenoma / Q000453:epidemiology*; D000428:Alcohol Drinking; D015984:Causality; D015179:Colorectal Neoplasms / Q000453:epidemiology*; D015986:Confounding Factors, Epidemiologic; D004032:Diet; D005260:Female; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008019:Life Style; D008297:Male; D011446:Prospective Studies; D012307:Risk Factors; D012907:Smoking