An Epidemiological Study of Lung Cancer Mortality in Japan and the United States in Relation to the Change in Per Capita Cigarette Consumption

In Japan, annual per capita cigarette consumption (cigarette consumption) increased rapidly during 1960s, and began to decrease around 1974. Although a similar change in cigarette consumption that occurred in the United States around 1964 was followed by a decrease in lung cancer mortality, the effect of the decrease in Japan on lung cancer mortality has yet to be analyzed. Therefore, the present study analyzed the relationship between the change in cigarette consumption and national lung cancer mortality in both Japan and the United States. The lag time between the peak year of cigarette consumption and the peak year of age-specific lung cancer mortality rate increased with age, indicating a birth cohort effect on lung cancer mortality. The birth cohorts with the highest lung cancer mortality rates were U.S. men aged 37 in 1961, Japanese men aged 49 in 1977, and U.S. women aged 43 in 1975. In these cohorts, the lung cancer mortality rates were around 10 per 100,000 when cigarette consumption began to decrease, suggesting that a decrease in lung cancer mortality can be achieved only when cigarette consumption decreases before the lung cancer mortality rate begins to increase