Psychoneuroimmunology (PNI) is a relatively new term in medicine, coined by Dr. Robert Ader in 1975. Since then, scientists have been able to demonstrate theoretical and some actual pathways from the brain (psycho) through the nervous system (neuro) to the immune system. Understanding this research will help you to learn how the body can develop disease and more importantly how to avoid disease and stay healthy.

Sexual abuse is distress at its worst and this will be explained thoroughly in the stress management section of this website. Stress, a neutral change in one’s life, can stimulate bodily hormones, which can lead to disease if the stress is interpreted negatively, a condition known as distress.

If you have been sexually abused, you have gone through an extremely stressful life event. The ACE studies have shown that multiple adverse events (including a combination of physical, sexual, or emotional childhood abuse) are much more likely to cause future health problems than a single abusive episode. However, your physical health, genetic defense, and psychological attitude can help you to avoid disease later in life. We are all different and something that causes cancer or another disease in one person may not cause it in another. Most SA survivors have never learned about the connection between PNI and health. Without question, they can benefit from this knowledge in their quest for a healthy and happy life.

If a life event (sexual abuse, divorce, car accident, house burning down, etc.) is significant to an individual, then the brain will trigger chemicals to be released through the nervous system. This can be life saving. For example, if a grizzly bear attacks you, your brain sends a chemical signal to trigger the stress response, which mobilizes blood from the skin and sends it to the heart to more effectively pump for maximum energy, enabling you to escape the bear’s attack. However, if the stress is chronic and the stress-induced chemicals remain in the body for long periods of time, the immune system will be compromised, allowing disease to develop.

While this section is intended to be understood by all, there must be some documentation to support these statements. Please don’t think that the quotation of medical studies is meant to confuse; rather, it is intended to give credence and to offer a chance for more reading to those who wish to delve further. For those who want to study this topic, Drs. Harold Koenig and Harvey Cohen have written a book, The Link between Religion and Health – Psychoneuroimmunology and the Faith Factor, which cites hundreds of medical studies and their implications.

In 1991 scientists showed that people under stress were more susceptible to upper respiratory infections (the common cold).(1) Why did this happen? To simplify, during stress, one of the brain’s messages travels through the nervous system to the adrenal glands, two small organs that sit on top of the kidneys. This message causes the adrenal glands to release a chemical called cortisol. This product, if in the bloodstream for a significant period of time, will weaken the immune response, inviting the growth of viruses (colds, AIDS, hepatitis), bacteria (bacterial infections), and cancer (cancerous cells).

The immune response is a rather complex bodily function designed to keep us healthy. Again, to avoid a lengthy scientific discussion, this section will be simplified. One of the kinds of immune cells is called a lymphocyte and the NK (natural killer) cell is a subtype of a lymphocyte. NK cells play important roles in killing viruses, bacteria, and cancer cells. These NK cells have been shown to possess receptors for corticosterone, showing that these cells can be activated or deactivated by messages from the brain.(2,3)

In autopsies of victims of accidents, pathologists often find cancer, which was previously undiagnosed, having been asymptomatic and contained by the body’s immune system. Dr. Levy and associates showed the progression of tumors in response to emotional stress.(4) Why did this happen? NK cells, if inhibited, cannot properly defend the body, thereby allowing tumors, viruses, and bacteria to grow without restriction. In two studies (5,6), researchers found that lowered levels of NK cell activity at the time of cancer diagnosis correlated with risk of recurrence or metastasis of the cancer.

Cortisol can decrease the function of the NK cells. One interesting study analyzed the results of 45 people jumping out of a parachute for the first time, an example of acute stress.(7) Scientists discovered that cortisol was produced and that NK cell activity significantly decreased during this time of stressful activity. Cortisol’s effect of hindering NK cell function has been described in other medical studies.

A recent (11/2006) study, performed by the PNI team at Ohio State University headed by Dr. Ronald Glaser, discovered a significant biochemical link between cancer and stress. When one is under stress, the body produces the hormone norepinephrine. This chemical produces a number of potentially lifesaving reactions, especially in times of danger (i.e., if one is being attacked by a grizzly bear). However this chemical can have adverse effects on the body if it accumulates over a period of time during lengthy episodes of distress, such as in cases of sexual abuse where mental pain lasts for years.

This study examined the effect of norepinephrine in cancerous tumor cells. Scientists found that it produces two compounds. One compound breaks down the tissue around the cancer cell, allowing it to spread to other parts of the body. Another compound promotes the growth of blood vessels around the tumor, allowing it to grow. So, if a person with cancer is under long-term distress, norepinephrine can cause the cancer to get worse. (8)

It is tempting to draw conclusions that stressful activities will automatically cause health problems, as illustrated by the biological pathways of PNI. Further experiments are needed. Still, studies show a significant risk for those affected by chronic stress of sexual abuse, especially in those cases of multiple abusive incidents, in developing debilitating disease. The good news is that studies also show that certain coping methods can decrease the flow of cortisol, thereby elevating immune function. These concepts will be discussed in the section on prevention and stress management.


1. Cohen, S., Tyrrell, D.A.I., & Smith, A.P. (1991) "Psychological stress and susceptibility to the common cold." New England Journal of Medicine 325, 606-612.
2. Spencer, R.L., et al. (1991) "Corticosterone regulation of type I and type II adrenal steroid receptors in brain, pituitary, and immune tissue." Brain Research 549, 236-246.
3. Spencer, R.L., et al. (1993) "Diurnal differences in basal and acute stress levels of type I and type II adrenal steroid receptor activation in neural and immune tissues." Endocrinology 133, 1941-1950.
4. Levy, S.M., et al. (1985) "Prognostic risk assessment in primary breast cancer by behavioral and immunological parameters." Health Psychology 4, 99-113.
5. Pross, H.F., & Lotzova, E. (1993). "Role of natural killer cells in cancer." Natural Immunity 12, 279-292.
6. Schantz, S.P., & Ordonez, N.G. (1991) "Quantitation of natural killer cell function and risk of metastatic poorly differentiated head and neck cancer." Natural Immunity and Cell Growth Regulation 10, 278-288.
7. Schedlowski, M. et al (1993). "Changes in natural killer cells during acute psychological stress." Journal of Clinical Immunology 13, 119-126.
8. Yang, Eric et al. (2006) "Norepinephrine Up-regulates the Expression of Vascular Endothelial Growth Factor, Matrix Metalloproteinase (MMP)-2, and MMP-9 in Nasopharyngeal Carcinoma Tumor Cells." Cancer Research 2006: 66: (21) 10357-10364.