In this entry, I would like to discuss the connection between stress, stressful life events, and their effect on asthma control. While the connection is still being worked out, there is evidence not only from clinical experience, but in research studies in humans and animals that stress can aggravate asthma.
Stress and asthma
There are many stressors that worsen asthma control in patients with asthma. These include allergens (such as cat dander and pollen), irritants (e.g., smoke), and cold infections. These are usually considered ‘exposures’, and we try to identify these triggers and avoid them if we can. Similarly, stress can be thought of as a type of exposure, though a psychological one, which can trigger asthma. Many patients find that stressful situations make them feel short of breath and wheeze, and that they need to use their quick relief inhaler for relief.
Stressful life events, which are less immediate, can also lead to worsened asthma control in certain individuals. A recent study measured quality of life related to asthma in a range of individuals and found that in people with similar baseline asthma severity, asthma control was poorer in subsets of individuals who had recent stressful life events, such as divorce or moving house. Another study, in children, found that the beneficial response to sublingual immunotherapy (similar to allergy shots) was decreased in children with stressful lives and life events. While the mechanism by which stress and stressful life events worsens asthma control, it is clear from the clinic and research studies that the connection is clear
What about stress and asthma in animal models
To better understand this connection, researchers have tried to replicate what is known in humans using animal models. In an animal model of asthma in mice, studies have shown that stressing animals leads to changes in the asthmatic response. These changes were found at different stages of developing asthma in these models, both early and late. Researchers hope that these models of stress and asthma will improve our understanding of the way that stress causes worsening asthma control.
Clearly, avoiding stress is not as easy an ‘exposure’ to avoid as other asthma triggers, such as pets and pollens. But being aware of this direct connection is important for all patients with asthma. Your doctor can help you to better control your asthma, especially for triggers that are less typical and like stress, poorly understood.