Smoking, alcohol drinking, green tea consumption and the risk of esophageal cancer in Japanese men.
BACKGROUND
Although smoking and alcohol drinking are established risk factors of esophageal cancer, their public health impact is unclear. Furthermore, the effect of green tea is controversial.


METHODS
The present study was based on a pooled analysis of two prospective cohort studies. A self-administered questionnaire about health habits was distributed to 9,008 men in Cohort 1 and 17,715 men in Cohort 2, aged 40 years or older, with no previous history of cancer. We identified 38 and 40 patient cases with esophageal cancer among the subjects in Cohort 1 (9.0 years of follow-up) and Cohort 2 (7.6 years of follow-up), respectively. Cox proportional hazards regression was used to estimate hazard ratios (HRs) of the risk of esophageal cancer incidence.


RESULTS
Cigarette smoking, alcohol drinking and green tea consumption were significantly associated with an increased risk of esophageal cancer. Compared with men who had never smoked, never drunk alcohol or green tea, the pooled multivariate HRs (95% confidence intervals) were 5.09 (1.80-14.40) (p for trend <0.0001), 2.73 (1.55-4.81) (p for trend=0.0002), or 1.67 (0.89-3.16) (P for trend=0.04) for men who were currently smoking > or =20 cigarettes/day, drinking alcohol daily, or drinking > or =5 cups green tea/day, respectively. The population attributable fractions of esophageal cancer incidence that was attributable to smoking, alcohol drinking and green tea consumption were 72.0%, 48.6%, and 22.1%, respectively.


CONCLUSIONS
Among the variables studied, smoking has the largest public health impact on esophageal cancer incidence in Japanese men, followed by alcohol drinking and green tea drinking.
Ishikawa
Atsunobu
A
Division of Epidemiology, Department of Public Health and Forensic Medicine, Tohoku University Graduate School of Medicine, Seiryo-machi, Sendai, Japan.
Kuriyama
Shinichi
S
Tsubono
Yoshitaka
Y
Fukao
Akira
A
Takahashi
Haruhiko
H
Tachiya
Hidekiyo
H
Tsuji
Ichiro
I
D000328:Adult; D000428:Alcohol Drinking / Q000009:adverse effects*; D015331:Cohort Studies; D004938:Esophageal Neoplasms / Q000209:etiology*; D006801:Humans; D007564:Japan; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects*; D013662:Tea / Q000009:adverse effects*
D013662:Tea