Discuss the role of stress in illness
One way that stress can cause illness is through immunosuppression. This can occur directly- cortisol
produced by the HPA axis inhibits the production of immune cells, or it can occur indirectly- stress influences
lifestyle behaviours (smoking, drinking) that has a negative effect on immune functioning. Keicolt Glaser
investigated how chronic stress during exams can cause illness: he took a blood sample from 75 medical
students, and tested them before the exam period (low stress) and on the first day of the exam (high stress).
They completed questionnaires measuring sources of stress and self-reported psychological symptoms. He
found that the activity of natural killer and killer T cells lowered between the first and second sample, and the
decline was greater in students who reported feeling lonely and experiencing other sources of stress. Kiecolt
also investigated chronic stress when caring for ill relatives. He compared the health and immune functioning
of caregivers (looking after relatives with alzheimers) with a matched control group, and all subjects had a
3.5mm punch biopsy wound and healing was assessed by photography of the wound. He found that wound
healing took significantly longer in caregivers than in controls- 49 days compared to 39 days.
Another way stress can cause illness is through cardiovascular disorders, which are disorders of heart and
blood vessels. For example, Wilbert-Lampen looked at incidences of heart attacks during football matches
(acute stressor) played in Germany during the 1996 world cup. He found that on days Germany played,
cardiac emergencies increased by 2.66 times compared to the control period. On the other hand, Yusuf et al’s
interheart study investigated chronic stress leading to heart attacks, by comparing 15000 people who had a
heart attack (myocardial infarction) with a similar number of people who had not, and he found that several
chronic stressors had a strong link to myocardial infarction including workplace stress and stressful life events-
role of stress was greater in obesity and and third behind smoking and cholesterol.
One limitation is that some studies have shown that stress can have immune-enhancing effects. For example,
in Dharbars’s research (2008) rats were subjected to mild stressors and found that this was enough to
stimulate a substantial immune response. Immune cells such as lymphocytes flooded the bloodstream and into
tissues in prepare for physical damage. Chronic stressors are dangerous because of their immunosuppressive
effects, but this research shows that acute stressors do not act on the immune system in the same way and
may stimulate protection against short term stress. This suggests that the relationship between stress, the
immune system and illness is complex and not yet fully understood. In addition, research into the role of stress
in illness can be considered nomothetic as it applies a set of laws to everyone and ignores the influence of
personality, for example that people may react differently to stress e.g people with type B personality are less
likely experience stress related illness, so perhaps an idiographic approach is more fruitful.
Another weakness of research into the role of stress is that it is correlational. Research simply establishes a
relationship between stress and illness, so it does not indicate causality. Psychologists are unable to conclude
that stress causes immune related illness or cardiovascular disease based on correlational analysis. This
lowers the validity of research into the role of stress in illness as cause and effect cannot be established.
However conducting correlational research is more ethical than conducting an experiment as studying the
relationship between stress and illness is more ethical than purposefully placing individuals under stress.
A strength is that there are practical applications. For example, Dharbar’s research may eventually lead to
patients having low doses of stress hormones before surgery to improve their chances of making a full and fast
recovery afterwards. Relaxation training could also be used to improve performance e.g Kiecolt-Glaser found
that students who took relaxation training to cope with stress had better immune functioning during an exam
period than those who didn’t bother with it. This suggests that research into the role of stress in illness must be
valid as therapies based on it are effective.
One way that stress can cause illness is through immunosuppression. This can occur directly- cortisol
produced by the HPA axis inhibits the production of immune cells, or it can occur indirectly- stress influences
lifestyle behaviours (smoking, drinking) that has a negative effect on immune functioning. Keicolt Glaser
investigated how chronic stress during exams can cause illness: he took a blood sample from 75 medical
students, and tested them before the exam period (low stress) and on the first day of the exam (high stress).
They completed questionnaires measuring sources of stress and self-reported psychological symptoms. He
found that the activity of natural killer and killer T cells lowered between the first and second sample, and the
decline was greater in students who reported feeling lonely and experiencing other sources of stress. Kiecolt
also investigated chronic stress when caring for ill relatives. He compared the health and immune functioning
of caregivers (looking after relatives with alzheimers) with a matched control group, and all subjects had a
3.5mm punch biopsy wound and healing was assessed by photography of the wound. He found that wound
healing took significantly longer in caregivers than in controls- 49 days compared to 39 days.
Another way stress can cause illness is through cardiovascular disorders, which are disorders of heart and
blood vessels. For example, Wilbert-Lampen looked at incidences of heart attacks during football matches
(acute stressor) played in Germany during the 1996 world cup. He found that on days Germany played,
cardiac emergencies increased by 2.66 times compared to the control period. On the other hand, Yusuf et al’s
interheart study investigated chronic stress leading to heart attacks, by comparing 15000 people who had a
heart attack (myocardial infarction) with a similar number of people who had not, and he found that several
chronic stressors had a strong link to myocardial infarction including workplace stress and stressful life events-
role of stress was greater in obesity and and third behind smoking and cholesterol.
One limitation is that some studies have shown that stress can have immune-enhancing effects. For example,
in Dharbars’s research (2008) rats were subjected to mild stressors and found that this was enough to
stimulate a substantial immune response. Immune cells such as lymphocytes flooded the bloodstream and into
tissues in prepare for physical damage. Chronic stressors are dangerous because of their immunosuppressive
effects, but this research shows that acute stressors do not act on the immune system in the same way and
may stimulate protection against short term stress. This suggests that the relationship between stress, the
immune system and illness is complex and not yet fully understood. In addition, research into the role of stress
in illness can be considered nomothetic as it applies a set of laws to everyone and ignores the influence of
personality, for example that people may react differently to stress e.g people with type B personality are less
likely experience stress related illness, so perhaps an idiographic approach is more fruitful.
Another weakness of research into the role of stress is that it is correlational. Research simply establishes a
relationship between stress and illness, so it does not indicate causality. Psychologists are unable to conclude
that stress causes immune related illness or cardiovascular disease based on correlational analysis. This
lowers the validity of research into the role of stress in illness as cause and effect cannot be established.
However conducting correlational research is more ethical than conducting an experiment as studying the
relationship between stress and illness is more ethical than purposefully placing individuals under stress.
A strength is that there are practical applications. For example, Dharbar’s research may eventually lead to
patients having low doses of stress hormones before surgery to improve their chances of making a full and fast
recovery afterwards. Relaxation training could also be used to improve performance e.g Kiecolt-Glaser found
that students who took relaxation training to cope with stress had better immune functioning during an exam
period than those who didn’t bother with it. This suggests that research into the role of stress in illness must be
valid as therapies based on it are effective.
