Distant stressors: traumatic experiences that occurred in the distant past yet can continue modifying the immune system because of their long-lasting emotional and cognitive consequences, such as child abuse, combat trauma or having been a prisoner of war. Much of their analysis goes on to review the similarities and differences among the 293 studies that they examined. These studies included a total of 18,941 subjects. "Stressful event sequences" appeared to be weakly associated with different immune consequences, depending on the type of event. There appeared to be different patterns for grief than for trauma, for example, but the associations weren't strong enough for the authors to make new claims. They recommended further study.
The authors did find that the most chronic stressors - those which change people’s identities or social roles, are more beyond their control and seem endless - were associated with the most global suppression of immunity. In such situations almost all measures of immune function dropped across the board. The longer the stress, the more the immune system shifted from potentially adaptive changes (such as those in the acute "fight or flight" response) to potentially detrimental changes, at first in cellular immunity and then in broader immune function. This analysis suggests that stressors that turn a person's world upside down and appear to offer no hope for the future probably have the greatest psychological and physiological impact.
The authors also found that age and disease status affected a person's vulnerability to stress-related decreases in immune function. It seems that illness and age make it harder for the body to regulate itself.
This is a ground-breaking meta-analysis that helps us understand the complex relationship between stress and the immune system. It should lead to new treatments and to better stress management programs, especially for patients with HIV or other disorders that compromise immunity.
Reference: Segerstrom & Miller, 2004. Psychological Stress and the Human Immune System: A Meta-Analytic Study of 30 Years of Inquiry Psychological Bulletin, 130, 4.
Last updated 11/5/05
