Fjölrit RALA - 22.03.1979, Side 96

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Change in total mortality:
Total mortality has decreased during the period but marked
changes have also occurred in the percentage of some disease
categories in total mortality. In figure 2, a comparison is
made of the percentage contribution to total mortality that
4 disease categories make in the period 1951-55 and 1973.
In male mortality, the most striking change is the increase
in coronary mortality in 1973 which has doubled compared with
1951-55 and is about 40% of total mortality in age group over
50. In female mortality, only a minor change in coronary
mortality has occurred.
Change in mortality for disease categories:
(1) Coronary artery disease: In figure 3 the relative change
in mortality for the period 1955-76 is shown. Comparison
between periods 1971-76 with previous periods must be done
with caution as previously mentioned. The death rate has
increased in all male age groups and ranges from 40-100%
up to 1970. There is only a minor increase or 5.4%-20%
for females. Absolute death rate is shown in table III
which gives the'mean rate for 100,000 inhabitants in 4
periods for the age group over 25. The death rate for
males has increased from 242 for the period 1955-59 to
417 in 1965-70, but for females from 165 to 241.
(2) Myocardial degeneration: Figure 4 shows that the relative
death rate has decreased 60% in 15 years for both sexes up
to 1970 and altogether 90% in 1975. Table III shows that
for the yea.rs 1955-59 the absolute death rate from myocard-
ial degeneration was 25% of that from coronary artery di-
sease (males 17%, females 33%), but during the period 1971-76
this percentage was only 1.8% (males 1%, females 2.6%).
(3) Coronary artery disease plus myocardial degeneration: Figure
5 shows that for males the relative death rate has increased
150% for the three youngest age groups, but for the older
age groups, it has increased 50% or less. Only minor changes
have occurred for females.
Table 1 shows absolute death rate for six age groups as a
mean for 5 periods. Comparison of the periods 1951-55 and