G. Corrao et al., EFFECT OF AGE, BIRTH COHORT AND PERIOD OF DEATH ON ITALIAN LIVER-CIRRHOSIS MORTALITY, 1972-1986, International journal of epidemiology, 22(3), 1993, pp. 475-482
Liver cirrhosis is one of the main causes of death in Mediterranean co
untries. A trend towards a global reduction in the mortality rate has
been recently reported. In order to clarify better this trend and in a
n attempt to hypothesize the future pattern of mortality, we analysed
data from 254 834 Italian subjects aged 30-79 who died from liver cirr
hosis during the period 1972-1986. We used a log-linear Poisson model
to examine the effects of age, calendar period of death and birth coho
rt. Our data confirm that both in the population as a whole and after
stratification for three geographical areas (Northern, Central and Sou
thern Italy) the mortality rate is decreasing. The age-effect analysis
showed an exponentially rising effect in the Southern population, in
accordance with the viral aetiology of cirrhosis, whereas an increased
effect followed by a decreased effect was observed in the Northern an
d Central population, suggesting the alcoholic aetiology for the disea
se. The results from the birth-cohort effect suggested that in the Nor
thern and Central populations mortality should continue to decrease ov
er the next decade, possibly due to the implementation of better preve
ntion programmes for cirrhotics and to decreased alcohol consumption i
n Italy. In the Southern population, however, mortality is still risin
g and this will probably continue for the next decade, as the generati
ons born between 1940 and 1950 who are at high risk of carrying chroni
c hepatitis B virus infection, reach the age of higher risk of death f
rom liver cirrhosis. We conclude that such an epidemiological approach
may help in understanding the variations of the trends of mortality f
rom liver cirrhosis and make it possible to hypothesize the future tre
nd pattern, thus helping to target more appropriately health care and
prevention programmes.