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Psychological treatment decreases colds and flu in children by increasing salivary immunoglobulin A

Hewson-Bower, Barbara (1994) Psychological treatment decreases colds and flu in children by increasing salivary immunoglobulin A. PhD thesis, Murdoch University.

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Psychoneuroimmunology research suggests the possibility of self-regulated immune system improvement. Psychological treatments utilising relaxation can increase levels of salivary immunoglobulin A (slgA), high levels of which are known to protect against cold and flu infection. No previous study has investigated the ability of children who suffer recurrent colds and flu to increase slgA with such psychological techniques. Furthermore, no previous research has been conducted on the clinical efficacy of increasing levels of baseline slgA.

The present thesis investigated both 'healthy children (those with two or less colds in the previous 12 months) and 'sick' children (those with ten or more colds in the previous 12 months). Their psychological profiles; levels of baseline slgA; and their immune system response to a natural cold infection were compared. In addition, the influence of both relaxation and acute stress on slgA was also investigated. Two treatment studies investigated whether psychological therapy reduces days of cold and flu illness, breaks the illness cycle and improves the emotional status of children with recurrent cold and flu problems.

'Sick' children differed both immunologically and psychologically from 'healthy' children. They had lower slgA, experienced more life event stress and had higher levels of depression, anxiety, introversion and neuroticism and lower levels of assertiveness.

SlgA increased during relaxation, relaxation with the suggestion to increase immune system proteins, and imagery visualising an increase in immune system proteins in the mouth, nose and ears. Furthermore, the level of relaxation predicted increases in slgA. Increases in slgA during the psychological techniques were similar in 'healthy' and 'sick' children. The acute stress of a mathematics test decreased levels of slgA in both 'healthy' and 'sick' children.

Two psychological treatments (Immune Enhancement therapy which increased slgA daily and Stress Management therapy which taught relaxation, problem solving and coping skills) were equally effective in reducing the days of cold and flu illness in 'sick' children in comparison to a waiting control group and their own pre-treatment baseline.

The psychological treatments increased baseline levels of slgA; improved the mucosal immune response to a natural cold infection; and improved the emotional status of children with a history of recurrent colds. Twelve month follow-up indicated that days of illness were reduced in the period of the next winter equivalent to the pre-treatment baseline; furthermore, gains to emotional status (depression, anxiety and assertiveness) were maintained at 12 month follow-up. The only improvement not maintained at twelve month follow-up was family satisfaction.

The studies in this thesis clearly demonstrate that psychosocial factors influence cold and flu infection. Psychological treatment reduces such infection and breaks the illness cycle in children who have recurrent upper respiratory tract infections. During treatment, baseline levels of slgA increased and the immune system showed a stronger response to such infection following therapy. This demonstrates self-regulated immune system enhancement. Furthermore, improvements in emotional status occurred during both treatment studies. Psychological improvements such as lower levels of depression are likely to result in less suppression of immune function, with consequent improvements in overall health and in the immune response to infection.

Item Type: Thesis (PhD)
Murdoch Affiliation(s): School of Social Sciences
Notes: Note to the author: If you would like to make your thesis openly available on Murdoch University Library's Research Repository, please contact: Thank you.
Supervisor(s): Drummond, Peter
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