Abstract
This paper analyzes the trend of mortality from cirrhosis of the liver in Japan based upon Vital Statistics published between 1955 and 1979.
The shape of the age-specific mortality curve in number for male cirrhosis of the liver was shown to form a unimodal with maximum frequency around the 60-64 age group in the period 1955-59. Recently, however, younger deaths from cirrhosis have gradually increased and in the period 1975-79 its shape dramatically changed to a bimodal peak: the younger peak representing the 45-49 age group and the older the 60-64 age group. Deaths occurred in this younger age peak were shown to be contributed mainly by the cohort born in 1930-40 by applying the Weibull model and Multiplicative model. No such peculiar pattern was found in the age-specific mortality curve for female cirrhosis.
Furthermore an analysis of the clinical records of the Tokyo Metropolitan Komagome Hospital during 1975-1983 showed that many of the male patients who died from cirrhosis of the liver were alcoholic cirrhotics and the shape of the age-specific mortality curve in number also had a similar bimodal curve.
Consequently, it was suggested that the increasing trend of mortality from cirrhosis of the liver in recent years could be explained by two main factors: the effect of the male cohort born in 1930-40 and the effect of the consumption of alcoholic beverages. As to this cohort characteristics, life environmental factors, such as experience of World War II, insufficient nutrition and labour conditions, were considered to be important determining factors.
