A Prospective Study of Stomach Cancer among a Rural Japanese Population: A 6-Year Survey

Stomach cancer mortality was prospectively studied among 9753 Japanese men and women who first responded to a mailed questionnaire in 1985 and were then followed through May 31, 1991. During this follow-up period, 57 stomach cancer deaths were identified. Current smokers had an increased risk of deaths from stomach cancer compared with never smokers (relative risk (RR) = 2.29, 95% confidence interval (CI): 1.15–4.56), but there was no dose-response to amount of cigarettes smoked. Daily alcohol drinkers who consumed 50 ml or more of alcohol per day also had a greater risk than nondrinkers (RR = 3.05, 95% CI: 1.35–6.91). There was no association between stomach cancer mortality and individual food consumption except a positive association with fruit intake. However, frequent use (≤3–4/week) of broiling of meats and traditional style Japanese salad preparation in their cooking procedures were positively associated with stomach cacer mortality. The RR values compared with infrequent use (≥1–2/month) were 2.27 (95% CI: 1–06–4.85) and 3.10 (95% CI: 1.40–6.85), respectively. A positive family history of cancer, especially stomach cancer, significantly increased the risk of stomach cancer deaths (RR=2.01, 95% CI: 1.12–3.63). The effects of these variables remained after adjustment for other variables.