The chronic process
The most commonly held view of the link between stress and illness suggests that stress
leads to disease due to a prolonged interaction of physiological, behavioural and psycho-
logical factors. For example, chronic work stress may cause changes in physiology and
changes in behaviour which over time lead to damage to the cardiovascular system. In
particular, chronic stress is associated with atherosclerosis which is a slow process of
arterial damage that limits the supply of blood to the heart. Further, this damage might
be greater in those individuals with a particular genetic tendency. This chronic process
is supported by research indicating links between job stress and cardiovascular disease
(Karasek et al. 1981; Lynch et al. 1997; Kivimaki et al. 2002). Such an approach
is parallel to Levi’s (1974) ‘stress-diathesis’ model of illness which is illustrated in
Figure 11.2.
However, there are several problems with a purely chronic model of the stress illness
link:
1.Exercise protects against the wear and tear of stress with more active individuals
being less likely to die from cardiovascular disease than more sedentary individuals
(Kivimaki et al. 2002). However, exercise can also immediately precede a heart attack.
2.The wear and tear caused by stress can explain the accumulative damage to the
cardiovascular system. But this chronic model does not explain why coronary events
occur when they do.
In the light of these problems, Johnston (2002) argues for an acute model.
The acute process
Heart attacks are more likely to occur following exercise, following anger, upon
wakening, during changes in heart rate and during changes in blood pressure
Fig. 11-2 Stress-diathesis model (after Levi 1974)STRESS AND ILLNESS 253