Risk factors for self-reported colon polyps.
OBJECTIVE
Investigate risk factors for colon polyp using multivariate analyses.


METHODS
In a group responding to a 1992 mail survey, we assessed the association between physician-diagnosed colon polyp and possible risk factors reported primarily 10 years earlier.


METHODS
Survey respondents within the Cancer Prevention Study II.


METHODS
Respondents, 72,868 men and 81,356 women, who reported no polyp diagnosis when questioned in 1982 at ages 40 to 64 years.


RESULTS
The characteristics of 7,504 men (10.3%) and 5,111 women (6.3%) reporting a first colon polyp were compared with those of participants who did not report a polyp. After adjustments for age, family history of colorectal cancer, and other potential risk factors, polyp occurrence was associated with 1982 histories of smoking, former smoking, alcohol use of at least two drinks per day (odds ratios [ORs] from 1.5 to 1.1; all p < .005), and a body mass index > or = 28 kg/m2 (men's OR 1.06; 95% confidence interval [CI] 1.00, 1.13; women's OR 1.08; 95% CI 0.99, 1.17). Polyps were also associated with a diagnosis of gallbladder disease or gallstone at any time and with gallbladder surgery up to 1982 (OR from 2.7 to 1.3; all p < .001). Polyp occurrence was inversely associated with 1982 histories of high exercise level (men's OR 0.83; 95% CI 0.76, 0.91; women's OR 0.90; 95% CI 0.78, 1.03), frequent aspirin use in women (OR 0.85; 95% CI 0.77, 0.95), and high parity in women (OR 0.84; 95% CI 0.75, 0.94). Among participants lacking a clinically normal gallbladder, the polyp risks associated with smoking and high body mass index were reduced (p < .04 for interactions).


CONCLUSIONS
Despite the limitations and potential biases in these self-reported data, the risk factors described here may be useful for identifying persons at modestly increased risk of having a colon polyp. The effect-modifying role of gallbladder status deserves further investigation.
Kahn
H S
HS
Department of Epidemiology and Surveillance Research, American Cancer Society, Atlanta, GA 30329-4251, USA.
Tatham
L M
LM
Thun
M J
MJ
Heath
C W
CW
D000328:Adult; D000570:American Cancer Society; D016022:Case-Control Studies; D003111:Colonic Polyps / Q000453:epidemiology*; D005260:Female; D005705:Gallbladder Diseases / Q000453:epidemiology; D006306:Health Surveys; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D012307:Risk Factors; D011795:Surveys and Questionnaires; D014481:United States / Q000453:epidemiology