19 Apr 2004
Medical News Today
A panel of experts speaking at Experimental Biology 2004 reports on new understandings of the mechanisms and pathways through which the body's hormonal response to stress alters immune system function and influences susceptibility, onset and exacerbation of mental and physical diseases, including atherosclerotic heart disease, depression, infectious diseases, and autoimmune diseases such as multiple sclerosis.
Thanks to a growing understanding of this process, scientists and clinicians increasingly are identifying individuals' risk factors and are teaching people - from high level executives to young children - simple coping behaviors that can successfully buffer the effect of stress on immune function and health.
The panel on "Alteration of Health by the Hormonal Response to Stress" is made up of members of the PsychoNeuroImmunology Research Society. Chaired by Dr. Bruce S. Rabin, University of Pittsburgh, the symposium is part of the scientific sessions of The American Association of Immunologists, one of the six sponsoring societies of Experimental Biology 2004.
How does stress create damage? Dr. William B. Malarkey, Ohio State University, describes how the perception of stress activates the interface between the endocrine (or hormonal) system and the immune system, initiating a cascade of physiological events. If the perception of stress is short-term, these hormonal changes fade away.
But if the stressful sensory input persists, the resulting dysregulation of the immune system initiates an inflammatory state that, if not stabilized, leads to symptoms and then established disease processes.
Many of these stress-induced inflammatory immune responses are precursors to the chronic diseases of aging, says Dr. Malarkey.
As the immune system modifies in response to hormones produced by stress as perceived by the brain, it produces soluble factors that affect the brain itself. Dr. Andrew H. Miller, Emory University, describes data indicating how this two-way interaction between the brain and immune system has a significant impact on causing and maintaining clinical depression.
Further stressors make things worse. Scientists increasingly recognize that stress in childhood or early life can create a hypervigilancy and hyperresponse to stressors later in life.
This intense response to stress is associated with an increased vulnerability to develop clinically significant depression during chronic immune stimulation, such as occurs during immunotherapy for cancer.
The immune system also plays an important role in the onset and progression of artherosclerotic coronary artery disease, including heart attacks.
By now, most scientists and clinicians – and many lay people – understand that psychological factors can act as risk factors for coronary diseases. Dr. Willem J. Kop, USUHS, explains three types of psychological risk factors and the psychoneuroimmunolgical pathways involved in the progression of coronary disease.
In brief, chronic psychological risk factors, such as hostility and low-socioeconomic status, play important roles at early disease stages. In the transition from stable to unstable atherosclerotic plaques, episodic factors like depression and exhaustion become more important. And finally, acute psychological triggers – mental stress and anger, for example – can promote myocardial ischemia and plaque rupture.
Thus, he says, "the specific hormonal and immunological pathways by which psychological factors promote heart disease change with increasing stages of coronary atherosclerosis."
Dr. Bruce Rabin describes behaviors that help ameliorate hormonal response to stress and how these can be taught or learned on one's own.
At the University of Pittsburgh Medical Center's Healthy Lifestyle Program, which he directs, stress coping behaviors are taught to groups of all ages, from all socioeconomic and educational levels, and to people with autoimmune disease, cancer survivors, and the children of parents who have or have survived cancer.
Techniques include deep breathing, guided imagery using CDs or scripts, and expressive writing (15 minutes writing about a stressor, then discarding the writing without reading it).
Dr. Rabin says that across all groups, people who utilize stress coping behaviors report improvement in the problems they face and in many aspects of their lives, including less depression, improved sleep patterns, enhanced social interactions, and improved ability to be more compliant with diets and good nutrition.
In addition to describing these and other advances in the biopsychosocial
approach to health and disease -- the usual exchange of new scientific
information that characterizes the interdisciplinary Experimental Biology
meetings, Dr. Rabin says he and other panel members believe it is important
information personally for those scientists (and journalists) at the meeting
whose own lives produce stress-related risks.
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