Cigarette smoking and risk of bladder, pancreas, kidney, and colorectal cancers in Iowa

PURPOSE: Aid-rough there are numerous reports on the effects of cigarette s moking and cancer, they have infrequently compared risks at more than one c ancer site after multivariate adjustment. We analyzed data from a populatio n-based case-control study that included five anatomic sites to evaluate th e association between cigarette smoking and each cancer site and to rank th e associations by site. METHODS: Study respondents included 1452 bladder. 406 kidney, 376 pancreati c, 685 colon, and 655 rectal cancer cases, as well as 2434 population contr ols. A self-administered questionnaire was used to collect information on c igarette smoking and other potential confounders including occupation, drin king water source, and dietary practices. Logistic regression models were u sed to calculate odds ratios (ORs) and 95% confidence intervals (CIs), afte r adjustment for age, total energy intake, and other site- and sex-specifrc confounders. RESULTS: In both sexes, cigarette smoking (ever vs. never) was associated w ith risk of bladder cancer (OR = 2.5: 95% CI, 2.0-3.1 for males; OR = 2.7; 2.0-3.6 for females) and pancreatic cancer (OR = 1.8; 1.2-2.8 for males; OR = 2.1; 1.4-3.1 for females). Cigarette smoking also increased the risk of kidney cancer among males (OR = 1.8; 1.3-2.7), and to a lesser degree, amon g females (OR = 1.2; 0.8-1.8). No association was found for colon or rectal cancer in either sex. CONCLUSIONS: Cigarette smoking increased the risk of bladder, kidney, and p ancreatic cancer in men and women. The rankings of multivariate-adjusted OR s from highest to lowest were bladder, pancreas, kidney, and colorectum, wi th little difference between men and women. (C) 2000 Elsevier Science Inc. All rights reserved.