Aim To investigate whether the stress of important examinations has an effect on the functioning of the immune system.
Procedure 75 medical students (49 males and 26 females) had blood samples taken one month before (relatively low stress) and during their final examinations (high stress). Immune function was assessed by measuring natural killer cells. Students were also given a questionnaire to assess psychological variables such as life events and stress.
Findings Natural killer cell activity was significantly reduced in the 2nd blood sample compared to the 1st. Killer cell activity was most reduced in participants who also reported high levels of life events and loneliness.
Conclusions Examination stress reduces immune functioning, potentially leaving the individual vulnerable to illness and infections. Immune function is also affected by psychological variables such as the stress of life events and feelings of loneliness. These long-term stressors may make individuals more vulnerable to the added effect of short-term stressors such as exams.
Aim To investigate the effect of stress on immune functioning.
Procedure Mice were placed on a rotating turntable for 5 hours and a control group were not rotated. The lymphocyte count of the mice were measured. Also, in a later study cancer cells were implanted and 1 group were rotated for 10 minutes per hour for 3 days and the other group acted as a control with no rotation.
Findings Lymphocyte count was significantly lower in the group that was rotated. The rotated group had significantly larger tumours by the end.
Conclusions Stress reduces immune functioning.
Aim To find out if scores on the Holmes and Rahe Social Readjustment Rating Scale (SRRS) correlated with the subsequent onset of illnes.
Procedure 2500 male American sailors were given the SRRS to assess the number of like events experienced in the past 6 months and their life change scores were recorded. Over the following 6 month tour of duty, detailed records were kept of each sailor’s health status. The life change scores were then correlated with the sailors’ illness scores.
Findings There was a positive correlation of +0.118 between life change scores and illness scores, and although small, the correlation was statistically significant showing that as life change scores increase, so did the frequency of illness.
Conclusions Experiencing life vents increases the chance of stress-related health breakdown. Since the correlation was not perfect, life events cannot be the only contributing factor to illness.
De Longis (1982)
Aim To compare life events and hassles to see which was a better predictor of stress related health problems.
Procedure A longitudinal study where 100 participants (all of whom were over 45 years old) were followed up over 1 year. They were assessed using self-report questionnaires using the Hassles scale and a life events scale and a health questionnaire. Participants completed these questionnaires once a month.
Findings Hassles were significantly correlated with poor health and this association appeared to be stronger than the association between life events and poor health.
Conclusions Hassles have more of an effect on poor health than life events.
Aim To investigate the factors that contribute to stress at work.
Procedure A natural experiment comparing two groups of workers in a saw mill. One group was 14 “finishers” who had to finish off the wood at the last stage of the processing. It was a very repetitive job which was fast paced and determined the rate at which the rest of the factory could work. The finishers had a high workload and higher demand than the other group which was 10 cleaners who could work at their own pace and had more varied work. The groups were compared on the following measures: the levels of adrenaline in their urine, the levels of stress related illnesses and the number of days off work (absenteeism).
Findings The finishers had high levels of adrenaline in their urine (suggesting greater activation of the SAM system), higher levels of stress related illnesses, (such as headaches) and more days off work compared to the cleaners.
Conclusions High workload – particularly repetitive fast paced work – is related to stress and to illness.
Aim To investigate whether lack of control at work predicted later development of coronary heart disease.
Procedure Data was gathered over 5 years from over 7,000 men and women (aged between 35 and 55) who worked as civil servants in London. Level of control at work was assessed using a self-report questionnaire. Coronary heart disease was assessed using self-report of chest pain (angina) and doctor diagnosis of symptoms of coronary heart disease. They also assessed other risk factors such as smoking, blood pressure and exercise. They then used correlation analysis to look for relationships between risk factors at the start of the study and coronary heart disease 5 years later.
Findings Low control at work was significantly related to coronary heart disease and it was a better predictor than other risk factors (such as smoking). High grade workers who had high workloads often were at lower risk of coronary heart disease than low grade workers with lower workload. This appeared to be because the high grade workers also had higher control at work.
Conclusions A number of factors are likely to interact to head to coronary heart disease. But lack of control at work makes a significant contribution to the risk of heart disease.
Friedman and Rosenman (1974)
Aim To investigate links between the Type A behaviour patterns and cardiovascular (heart) disease.
Procedure Using structured interviews, 3200 Californian men aged between 39 and 59 were categorised as either Type A, Type X (balanced) or Type B. The sample was followed up for 8 and a half years to assess their life style and health outcomes.
Findings By the end of the study 257 men in the sample had developed coronary heart disease of which 70% were from the Type A group – twice the rate of heart disease than found in the Type B group. The difference in the incident of CHD between the 2 groups was independent of lifestyle factors such as smoking and obesity that are known to increase the chances of heart disease.
Conclusions The Type A behaviour pattern increases vulnerability to heart disease.
Lee and Watanuki (2007)
Aim To investigate the differences in reaction to stressful between Type A and B personalities.
Procedure 14 Type A and 16 Type B students were shown unpleasant visual images. During the recovery phase they were shown either forests or grey screens. Their heart rate was measured throughout.
Findings Type A had a higher heart rate when viewing the stressful images than Type B and recovery to resting heart rate was reduced in Type A.
Conclusions Type A have a higher sympathetic response and a lesser parasympathetic response.
Aim To investigate if hardiness has effect on the likelihood of contracting stress related illnesses.
Procedure 800 American business executives stress levels was assessed using: the Holmes and Rahe’s SRRS, illness records and a hardiness questionnaire which measured: control, commitment and challenge.
Findings Approximately 150 of the participants were classified as high stress according to their SRRS scores. Of these, some had a low illness records whereas others were high, suggesting that something else was modifying the effects of stress. The individuals in the high stress/low illness group scored high in all 3 aspects of the hardy personality whereas the high stress/high illness group scored lower on these variables.
Conclusions To investigate if hardiness has effect on the likelihood of contracting stress related illnesses.
Aim To investigate the effectiveness of benzodiazepines (BZ) in the treatment of social anxiety.
Procedure 75 patients with social-anxiety were randomly allocated to either BZ medication or to a placebo for 10 weeks and their anxiety was assessed at the start and end of treatment. Patients were followed up again 2 years later.
Findings 78% of those treated with BZ reported an improvement in symptoms compared to 20% of the placebo group. Those treated with BZ did report some side effects such as unsteadiness and dizziness. At two year follow-up the group that had been treated with BZ were significantly better than the control group.
Conclusions BZ drugs may have both have a short and long term beneficial effect on the treatment of social anxiety.
Aim To investigate the use of beta-blockers in the treatment of stage fright in musicians.
Procedure 34 singers were given different doses of a beta-blocker or a placebo during end of term examinations.
Findings Low doses of beta-blockers produced only small improvements in performance and high doses significantly impaired performance compared to the placebo.
Conclusions Beta-blockers may be of only limited benefit to performances.
Aim To investigate the effectiveness of Stress Inoculation Training (SIT).
Procedure Patients had phobias of snakes and rats. All patients had 1 phobia treated either with SIT or with a comparison treatment – systematic desensitisation (gradual exposure to the source of fear.
Findings SIT was effective at treating the phobia it was targeted at and it reduced the fear of the non-treated phobia.
Conclusions SIT is effective and can be generalised to other fears and anxieties.
Aim To investigate the effectiveness of Stress Inoculation Training (SIT).
Procedure Treated women who had experienced physical or sexual assault and who were diagnosed with Post traumatic stress disorder. Half were treated with SIT and the other with prolonged exposure which involves going back over the memory of the traumatic event again and again. Post-traumatic stress symptoms were assessed after treatment.
Findings Both treatment strategies reduced PTSD symptoms, but the exposure therapy was more effective in reducing the anxiety symptoms.
Conclusions Prolonged exposure is more effective at reducing PTSD symptoms than SIT.