[Cigarette smoking and gastric cancer risk in a community-based cohort study in Korea].
OBJECTIVE
Gastric cancer is the most common incident cancer in Korea. Although Helicobacter pylori infection is the most important risk factor for the development of gastric cancer, cigarette smoking has also been suggested to play an important role in the development of gastric cancer. The objective of this study is to evaluate the relationship between cigarette smoking and gastric cancer risk in a Korean population.


METHODS
The study population consisted of 13,785 subjects who had been enrolled in the Korean Multi-Center Cancer Cohort between 1993 and 2002. As of December 2002, 139 incident gastric cancer cases were ascertained through the Korea Central Cancer Registry and the National Death Certificate Database. Relative risks (RR) and 95% confidence intervals (CI) for gastric cancer were estimated using Cox's proportional hazard model adjusted for age, education, alcohol drinking status and history of gastritis or ulcer.


RESULTS
Significant dose-response relationships were observed between the duration of smoking and the risk of gastric cancer among the male subjects in comparison to non-smokers: men who smoked for 20-39 years had a 2.09- fold (95% CI 1.00-4.38) increase, and those who smoked for more than 40 years had a 3.13-fold (95% CI 1.59-6.17) increase in the risk of gastric cancer (P trend<0.01).


CONCLUSIONS
This study suggests that a longer duration of cigarette smoking may increase the risk of gastric cancer development in a dose-response manner in Korean men. The association between smoking and gastric cancer risk in women should be verified in future studies with a larger number of cases.
Kim
Yeonju
Y
Department of Preventive Medicine, Seoul National University College of Medicine, Seoul, Korea.
Shin
Aesun
A
Gwack
Jin
J
Jun
Jae Kwan
JK
Park
Sue Kyung
SK
Kang
Daehee
D
Shin
Hai-Rim
HR
Chang
Soung-Hoon
SH
Yoo
Keun-Young
KY
D000368:Aged; D015331:Cohort Studies; D005260:Female; D006801:Humans; D015994:Incidence; D007723:Korea / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D018570:Risk Assessment; D012307:Risk Factors; D012309:Risk-Taking; D012907:Smoking / Q000009:adverse effects / Q000453:epidemiology*; D013274:Stomach Neoplasms / Q000453:epidemiology* / Q000209:etiology; D013997:Time Factors