In all my years of practice, I have taken notice of a worrisome trend. Stress-related illnesses are on the rise among all demographics. Men and women of all ages are increasingly experiencing distressing circumstances and becoming exposed to elevated incidences of various dangerous conditions. Additionally, while the majority of the population is aware of the emotional damage that stress can cause such as excessive anxiety, overbearing guilt, and wild mood swings; the extent with which stress can affect the physical integrity of an individual is ignored by most. Comprehensive research into the subject has produced evidence that stress has a quantifiable harmful effect on the entire immune apparatus. It is therefore imperative that we educate the general populace regarding the obvious and not so obvious repercussions of stress on the human body. It is my firm belief that an informed patient will be able to make better decisions about his or her well-being.
WHAT IS STRESS?
Stress is a physiological reaction by the organism in which various biological mechanisms are activated to face a perceived threat. Stress is actually a biological necessity, and under the correct circumstances, it is able to provide the body with essential benefits. However, given a different set of circumstances, and especially when stress is experienced continually over time, stress functions as a triggering mechanism for various health complications.
To complicate matters even further, emotional stress is highly subjective. Physiological stress and psychological stress may vastly differ or be virtually the same, and as long as there is a perceived threat, a stress response will be activated. However, not everybody will “become” stressed over the same factors, as it all boils down to the perception of the threat, whether it is physical or psychic. Also significant is how capable the patient feels of dealing with or terminating the threat.
Before we are able to understand the methods of interaction between a stressor and the immune system we must elucidate precisely what comprises the immune apparatus.
WHAT IS IMMUNE SYSTEM?
The human body is in a perpetual state of conflict with its environment. Constant interaction with various biological agents and contaminants makes having a protective barrier an absolute necessity. This biological barrier or shield is what we refer to when we talk about the immune system. The immune apparatus is comprised of billions of differentiated and specialized cells that, as a unit, move through the bloodstream to defend the body’s organs and other various tissues against attack by bacteria, viruses, and toxins.
So how does stress interact with such a vast and complicated system? And what effect will it have on the body and its ability to fend off disease?
HOW DOES STRESS AFFECT THE IMMUNE SYSTEM?
The first assumption we must make in order to link the causal link between stress and reduced immune function is that the various negative affective states, such as anxiety and depression, can exert direct effects on biological processes. In this regard, exposure to chronic stress is generally considered the most toxic because it typically results in far-reaching and often permanent changes to behavioral responses that increase the susceptibility to contracting a disease. However, it is the body’s endocrine response and its reaction to continued stressors that correspond to a reduction of the immune response.
HPA AND SAM
There are two primary endocrine response mechanisms which are singularly reactive to the presence of continued stressor factors. These are:
The Hypothalamic-pituitary-medullary system: This particular axis of endocrine activity is in control of the body’s reactions to stress as well as the regulation of various processes such as digestion, sexuality, energy metabolism, emotive response, and immune function. It is intricately involved in the neurological development of functional diseases such as bipolar disorder, ADHD, major depression, chronic fatigue, and even alcoholism.
The Sympathetic-adrenal-medullary system: This axis is crucial organism’s ability to react to outside stimuli. Its most prominent feature is the regulation of the norepinephrine and epinephrine cycle, also known as the fight or flight mechanism. Stress affects the system’s ability to regulate adrenal function and therefore maintain homeostasis, which can significantly impact blood pressure and blood glucose levels.
Therefore the effects of stress on these two systems have the potential to affect the regulation of immune and inflammatory responses to infections, autoimmune disease, and even cancer. There is clinical evidence to suggest that psychological stress can alter innervation of lymph tissue through the synthesis of HPA and SAM activated hormones which bind to immune cells.
IS THE RELATIONSHIP BETWEEN STRESS RESPONSE AND IMMUNE ACTION FORTUITOUS?
There is no such thing as an accidental biological process, and there is mounting evidence to suggest that stress sensitivity of the immune apparatus to stressors is not an exception to the rule. Various studies have indicated that this relationship exists out of a necessity for efficient coordination of behavioral responses to infection and inflammation. For example, the well-documented immunosuppressive effect of corticosteroid release suggests that there is an important link between elevated synthesis of cortisol during acute and chronic stress states and repressed immune response.
In conclusion, the adverse effect of stress on the immune system comes down to the way the central nervous system interacts with the endocrine system and the immune apparatus itself; and any irregularity in this intricate relationship has the potential to suppress the body’s immune response. Stress-generating events can vary widely. Negative thoughts and emotions can be elicited by normal situations as well as by trauma. A person experiencing job strain and a person recuperating from a natural disaster are both at risk of experiencing the immune deregulating effect of stress. Therefore we, as individuals, must do everything in our power to mediate and control our response to the many stressors around us.
- Steptoe, Andrew, Mark Hamer, and Yoichi Chida. “The effects of acute psychological stress on circulating inflammatory factors in humans: a review and meta-analysis.” Brain, behavior, and immunity 21.7 (2007): 901-912.
- Maes, Michael, et al. “The effects of psychological stress on humans: increased production of pro-inflammatory cytokines and Th1-like response in stress-induced anxiety.” Cytokine 10.4 (1998): 313-318.
- Khansari, David N., Anthony J. Murgo, and Robert E. Faith. “Effects of stress on the immune system.” Immunology today 11 (1990): 170-175.
- Rabin, Bruce S. Stress, immune function, and health: The connection. New York:: Wiley-Liss, 1999.
- Segerstrom, Suzanne C., and Gregory E. Miller. “Psychological stress and the human immune system: a meta-analytic study of 30 years of inquiry.” Psychological bulletin 130.4 (2004): 601.
- Glaser, Ronald, and Janice K. Kiecolt-Glaser. “Stress-induced immune dysfunction: implications for health.” Nature Reviews Immunology 5.3 (2005): 243.
- Dantzer, Robert, and Keith W. Kelley. “Stress and immunity: an integrated view of relationships between the brain and the immune system.” Life sciences 44.26 (1989): 1995-2008.
- Selye, Hans. “Stress and disease.” The laryngoscope 65.7 (1955): 500-514.
- Cohen, Sheldon, Denise Janicki-Deverts, and Gregory E. Miller. “Psychological stress and disease.” Jama 298.14 (2007): 1685-1687.
- How to Boost your immune system.