Sex Differential in Life Expectancy at Birth in Japan (1) The Sex Differential in Recent Years

Life expectancy of woman at birth usually exceeds that of man in developed countries. The purpose of this study is to explain the reason of such sex differential in life expectancy at birth in Japan in recent years, analyzing sex differentials of age-specific death rates and mortality rates by causes of death. The calculated life table and vital statistics in 1990 were employed for the analysis. The analysis of age-specific death rate showed that the sex differential of mortality in age 50 and over explained around 70% of the sex differential in life expectancy at birth. In contrast, the sex differential of mortality rate in age 0 explained only 1 % of the difference. From the analysis of mortality rate by causes of death, it was shown that sex differentials of mortality from malignant neoplasm, heart diseases, cerebrovascular diseases, pneumonia and bronchitis, suicide, and accidents mainly contributed to the recent sex differential of life expectancy at birth. Of these causes, malignant neoplasm was the leading contributor to the sex differential in life expectancy at birth. From these results, it is considered that elongation of male life expectancy at birth would be possible by improving the life-style.