An Analysis on Danish Micro Data - School of Economics and ...

experience symptoms of depression once in their life. After the first depression, the risk of getting
another depression raises to 50 % and after a second depression the risk for recurrence rises to 70
%. 10 The lifetime-risk is twice as high for women, as it is for men. The onset of the disease occurs
typically between the age of 40 and 50. The co-morbidity is very high, since 50 % of the patients
also suffer from other mental disorders. Also the mortality for depression is high, since it can lead
to suicide. Among the very depressed, about 15 % commit suicide. 11 As earlier mentioned, the risk
of recurrence is high, and in the worst case it can lead to a chronical depression which lasts for
several years.
In general the prognosis for depressive episodes is good, but on the long term with recurrent
episodes the prognosis is less favourable. This is due to the fact that the risk of suicide is high and a
lot of patients take early retirement. 12
Aetiology
Both internal and external factors can cause a depression. Certain factors cause a depression for one
person, but not the other. This can be explained by the so-called vulnerability-stress model. 13 The
development of a depression can be explained as a function of a biological foundation for
developing a depression, which is partly genetically determined, and of a trauma. 14 The larger the
biological foundation is the smaller trauma it takes to trigger off a depression. <strong>An</strong>d this also works
the other way around; a larger trauma just requires a small biological foundation to trigger off a
depression. The psychological and biological causes of depression are connected. The vulnerabilitystress
model can be seen from several angles. A person can be particularly vulnerable due to either
psychological or biological reasons. From a psychological viewpoint the person can have either a
very perfectionist personality or a very dependent personality. Also biological factors play a part
when a person is very vulnerable to depression. These factors have not been entirely discovered yet,
but one knows that heritability plays a part in the development of depression. Children have a 10-15
% increased risk of developing a depression if either one of their parents has had depressive
episodes.
The stress-component can also be seen from both a psychological and a biological angle. External
events, like serious illness, accidents, divorce or death, can trigger off a depression. Seen from a
10 Berndt et al. (2002)
11 Day Poulsen et al. (2004)
12 Day Poulsen et al. (2004)
13 Day Poulsen et al. (2004)
14 Day Poulsen et al. (2004)
6