Smoking and cancer risk in Korean men and women.
OBJECTIVE
In Korea, male smoking prevalence is among the world's highest, and mortality rates from smoking-caused cancers, particularly lung cancer, are escalating. This cohort study examined the effects of cigarette smoking on the risk of cancer mortality and incidence, and characterized the relationship of cancer risk with the amount and duration of cigarette smoking.


METHODS
A nine-year prospective cohort study was carried out on 1,212,906 Koreans, 30-95 years of age. The study population includes participants in a national insurance program, who completed a questionnaire on smoking and other risk factors. The main outcome measures were death from cancer and cancer incidence, obtained through record linkage. At baseline, 472,970 men (57.0%) and 20,548 (5.4%) women were current cigarette smokers.


RESULTS
In multivariate Cox proportional hazards models, controlling for age, current smoking among men increased the risks of mortality for cancer of the lung (relative risk (RR), 4.6; 95% confidence interval (CI), 4.0-5.3) and other cancers, including larynx, bile duct, esophagus, liver, stomach, pancreas, bladder, and also leukemia. Current smoking among women increased the risk of lung cancer mortality (RR = 2.5, 95% CI = 2.0-3.1). Similar results were found for incidence among men and women.


CONCLUSIONS
In Korea, smoking is an independent risk factor for a number of major cancers. The findings affirm the need for aggressive tobacco control in Korea in order to minimize the epidemic of smoking-caused disease.
Jee
Sun Ha
SH
Department of Epidemiology and Health Promotion, Graduate School of Public Health, Yonsei University, Seoul, Korea. jsunha@yumc.yonsei.ac.kr
Samet
Jonathan M
JM
Ohrr
Heechoul
H
Kim
Jung Hee
JH
Kim
Il Soon
IS
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016001:Confidence Intervals; D005260:Female; D006266:Health Education / Q000379:methods; D006801:Humans; D015994:Incidence; D007723:Korea / Q000453:epidemiology; D008175:Lung Neoplasms / Q000453:epidemiology* / Q000209:etiology* / Q000401:mortality; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000453:epidemiology / Q000209:etiology; D016016:Proportional Hazards Models; D012307:Risk Factors; D017678:Sex Distribution; D012737:Sex Factors; D012907:Smoking / Q000009:adverse effects* / Q000453:epidemiology* / Q000401:mortality; D016540:Smoking Cessation / Q000379:methods; D011795:Surveys and Questionnaires; D016387:Women's Health