(Glenn and Weaver 1981). These links between relationship status and quality have
been understood using a range of literatures including attachment theory, life events
theory and self-identity theory. Kiecolt-Glaser and colleagues (Kiecolt-Glaser et al. 1987,
2003) have explored these links within the context of stress and the role of immune
function. In one study they assessed the associations between marital status and marital
quality and markers of immune function. Their results showed that poor marital quality
was associated with both depression and a poorer immune response. In addition, they
reported that women who had been recently separated showed poorer immune response
than matched married women and that time since separation and attachment to the ex-
husband predicted variability in this response (Kiecolt-Glaser et al. 1987). In another
study they explored the relationship between measures of stress hormones during the
first year of marriage and marital status and satisfaction ten years later. The results
showed that those who were divorced at follow-up had shown higher levels of stress
hormones during conflict, throughout the day and during the night than those who were
still married. Further, those who marriages were troubled at follow-up also showed
higher levels of stress hormones at baseline than those whose marriages were
untroubled. This suggests that stress responses during the first year of marriage are
predictive of marital dissatisfaction and divorce ten years later (Kiecolt-Glaser et al. 2003).
Research therefore shows a link between stress and illness. For many, this stress takes
the form of discrete events. However, many people also experience chronic stress caused
by factors such as poverty, unemployment or work load. Much research has focused
on two aspects of chronic stress, namely job stress and relationship stress. This research
indicates an association between chronic stress and illness, with a role for changes in
immune function. However, there exists much variability in the stress illness link. In part
this can be explained by factors such as stress reactivity and stress recovery which have
been described above. However, research also highlights a role for other moderating
variables which will now be considered.
WHICH FACTORS MODERATE THE STRESS–ILLNESS LINK?
The relationship between stress and illness is not straightforward, and there is much
evidence to suggest that several factors may moderate the stress–illness link. These
factors are as follows:
Exercise: this can cause a decrease in stress (see Chapter 7).
Coping styles: The individual’s type of coping style may well mediate the stress–illness
link and determine the extent of the effect of the stressful event on their health status
(see Chapter 3 for a discussion of coping with illness).
Social support: increased social support has been related to a decreased stress response
and a subsequent reduction in illness.
Personality: it has been suggested that personality may influence the individual’s
response to a stressful situation and the effect of this response on health. This has
STRESS AND ILLNESS 267