Influence of Death from Circulatory Diseases on Life Expectancy at Birth in Japan

This study aims to evaluate the contribution of the change in circulatory diseases mortality to the life expectancy at birth observed during the years 1955-1995 in Japan. We used data on the population and the number of deaths by cause, age, and sex in 1955, 1965, 1975, 1985, and 1995. The contribution of different ages and causes of death to the change in life expectancy were examined with the method developed by Pollard. We found that the reduction in circulatory diseases mortality contributed to the improvements in life expectancy for both sexes during the decade 1975-1985. Much of this was due to the decrease in cerebrovascular disease. In the years 1985-1995, however, the contribution of cerebrovascular disease decreased in both sexes, while that of heart disease grew to become the largest of any single condition. By age, the contribution of all circulatory diseases increased among the elderly in recent years. The contribution of the change in circulatory diseases mortality to the life expectancy at birth has increased in recent years but seems to have reached a plateau. The weight against improvements in life expectancy in middle-aged people has shown little change, so that reducing the mortality rate in middle-aged people is now a major issue.