A pooled analysis of bladder cancer case-control studies evaluating smoking in men and women.
OBJECTIVE
A recent study suggested that risk of bladder cancer may be higher in women than in men who smoked comparable amounts of cigarettes. We pooled primary data from 14 case-control studies of bladder cancer from Europe and North America and evaluated differences in risk of smoking by gender.


METHODS
The pooled analysis included 8316 cases (21% women) and 17,406 controls (28% women) aged 30-79 years. Odds ratios (ORs) and 95% confidence intervals (95% CI) for smoking were adjusted for age and study. Exposure-response was evaluated in a stratified analysis by gender and by generalized additive models.


RESULTS
The odds ratios for current smokers compared to nonsmokers were 3.9 (95% CI 3.5-4.3) for males and 3.6 (3.1-4.1) for females. In 11 out of 14 studies, ORs were slightly higher in men. ORs for current smoking were similar for men (OR = 3.4) and women (OR = 3.7) in North America, while in Europe men (OR = 5.3) had higher ORs than women (OR = 3.9). ORs increased with duration and intensity in both genders and the exposure-response patterns were remarkably similar between genders.


CONCLUSIONS
These results do not support the hypothesis that women have a higher relative risk of smoking-related bladder cancer than men.
Puente
Diana
D
Respiratory and Environmental Health Research Unit, Municipal Institute of Medical Research (IMIM), 80 Dr Aiguader Rd., Barcelona, 08003, Spain.
Hartge
Patricia
P
Greiser
Eberhard
E
Cantor
Kenneth P
KP
King
Will D
WD
González
Carlos A
CA
Cordier
Sylvaine
S
Vineis
Paolo
P
Lynge
Elsebeth
E
Chang-Claude
Jenny
J
Porru
Stefano
S
Tzonou
Anastasia
A
Jöckel
Karl-Heinz
KH
Serra
Consol
C
Hours
Martine
M
Lynch
Charles F
CF
Ranft
Ulrich
U
Wahrendorf
Jürgen
J
Silverman
Debra
D
Fernandez
Francisco
F
Boffetta
Paolo
P
Kogevinas
Manolis
M
D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D016001:Confidence Intervals; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D015995:Prevalence; D012307:Risk Factors; D012737:Sex Factors; D012907:Smoking / Q000453:epidemiology*; D001749:Urinary Bladder Neoplasms / Q000453:epidemiology*