Stress can affect virtually every system in the body and has been linked to increased risk of illness, heart disease, and even premature death. One of the systems most sensitive to stress is the immune system. Research published in Stress Medicine (1991;7:53–60) found that psychological stress can reduce the activity of natural killer cells, an important component of immune defense.
Stress has also been associated with increased susceptibility to infection. A study published in the New England Journal of Medicine (August 29, 1991;325[9]:606–612) reported that students experiencing higher levels of stress were more likely to develop colds. Even in serious chronic illness, stress appears to influence outcomes. An article published in Medical Tribune (February 10, 1994) reported that AIDS patients who were pessimistic about their health became ill more rapidly and died earlier than those with a more positive outlook.
The effects of stress extend beyond immune function. Patients with irritable bowel syndrome showed improvement when stress management strategies were incorporated, according to research published in Digestion (1991;50:36–42). Stress has also been linked to impaired fertility, as reported in Medical Tribune (December 1, 1994;16).
Cancer outcomes may likewise be influenced by psychological factors. In a study of 68 melanoma patients undergoing surgery, those who received psychological counseling experienced lower rates of cancer recurrence and reduced mortality compared with patients who did not receive psychological support.
Cardiovascular health is particularly vulnerable to chronic stress. High cholesterol, elevated blood pressure, and heart disease have all been associated with stress, according to research published in the Journal of the American College of Nutrition (1992;11[5]:609, Abstract 40). Additional findings reported in Postgraduate Medicine (January 1991;89[1]:159–164) suggest that stress may contribute to coronary artery spasm, plaque formation, increased platelet aggregation, and thrombus formation. Stress has also been linked to sudden cardiac death.
