Stress and Asthma: The relation between the two
Stress has an all encompassing effect on our body. Though a certain level of stress is good for us as it prods us into action, chronic stress has been implicated in a number of physiological and psychological reactions that influence our physical and mental well being.
A direct connection has been long observed between asthma and stress. In fact, initially asthma was thought to be a psychosomatic disease. But, it has been established that it has a definite physiological basis. Asthma has several triggers like pollen, pet dander, cigarette smoke, viral infections that can provoke an exacerbation of symptoms. Stress is yet another factor that can cause the characteristic wheezing and breathlessness of asthma.
Stress, in itself, does not cause asthma to develop in people. However, it can worsen asthma symptoms in people who already have this disease. Besides, it has also been seen that asthma management is more difficult when there is underlying stress.
Stress is known to enhance some physiological characteristics of inflammation that are normally seen in asthma. In other words, it further increases the level of inflammation caused by physiological irritants. Thus, what we have is a heightened level of response by the airways which not only increases the duration but also the severity and number of exacerbations.
There is a difference in the way the body reacts to acute stress and chronic stress. Studies have shown that an acute stress is more likely to cause asthma exacerbations in the presence of existing chronic stress. For those who do not have any longstanding stress, there may not be an asthma aggravation in the event of acute stress. There is a robust system within the body to handle stress, be it physical or mental.
As far as the biological response is concerned, acute stress is controlled by the sympathetic-adrenal-medullary (SAM) axis which produces a quicker response. The SAM response activates the fight or flight response and the PNS (peripheral nervous system) brings the body back to normal once the stress is over. On the other hand, the hypothalamic-pituitary-adrenal (HPA) axis controls the response to chronic stress. In the HPA system, the hypothalamus activates the pituitary gland which prompts the adrenal to release ACTH. This causes release of cortisol and glucose in the face of biological stress.
The HPA axis also has its own system of bringing the body back to normal to prevent overload of stress. There is a constant adjustment of hormone levels to maintain a state of balance. This is described as the allostatic load. Individuals with high allostatic load are always in a state of anxiety that can lead to pronounced damage within the body.
Normally increased levels of cortisol should suppress the immune system. Paradoxically, in the case of chronic stress this does not happen. The body remains in a state of arousal/stress and does not get the opportunity to return to normal. This is due to the constantly increased levels of cortisol as well as catecholamines circulating within the body. With asthma sufferers, it has been hypothesised that this eventually causes a decreased responsiveness by cortisol receptors. This accounts for an exaggerated asthma symptoms in the face of chronic stress.
Written by: Nandita tripati
Date last updated: January 10, 2015