Why stress exacerbates asthma in kids
It is known that stress exacerbates the symptoms of asthma in children, but the biological reason for this has been unknown. Now, scientists in Canada have discovered that a stressful home life diminishes the expression of certain proteins on the surface of cells that regulate airway responses and inflammation.
“Collectively, these findings suggest that in children and adolescents with asthma, the quality of home life and family relationships are important determinants of health and well-being and appear to have stronger effects than other life domains, such as academics and peer relationships,” conclude Drs. Gregory E. Miller and Edith Chen, from the University of British Columbia in Vancouver.
They interviewed 39 children with asthma and 38 healthy children, ages 9 to 18, regarding acute and chronic stress over the preceding 6 months. Blood specimens were obtained to measure levels of the so-called glucocorticoid receptor and beta-2-adrenergic receptor.
In general, children with asthma expressed higher levels of beta-2-adrenergic receptor and glucocorticoid receptor than did healthy children.
However, the researchers found that asthmatic children exposed to chronic stress, such as abrasive family relationships or an unstable home environment, expressed less beta-2 than those not exposed to chronic stress, whereas healthy children expressed more.
Major life events alone did not affect expression of these proteins in either group of children.
But in children with asthma who experienced a major life event in the previous 3 months along with chronic stress, the expression of beta-2-adrenergic receptor decreased 9.5-fold and expression of glucocorticoid receptor decreased 5.5-fold. In healthy children, this pattern was reversed and was weaker.
In Proceedings of the National Academy of Sciences, Miller and Chen explain that attenuated expression of both receptors would likely lead to airway inflammation and airway constriction after exposure to allergic triggers. It could also diminish patients’ sensitivity to asthma medications, they suggest.
SOURCE: Proceedings of the National Academy of Sciences USA 2006.
Tell-a-Friend comments powered by Disqus