Life offers a succession of challenges and demands. Sometimes we find them stimulating and exciting; other times they seem depressing and overwhelming. We are continually responding to these challenges while trying to maintain our equilibrium. Sometimes the demands really seem to pile up or become very difficult to meet. It feels as though we are in a permanent fight-or-flight response and just can't relax. We may experience tension headaches, nervous stomachs, or sleeplessness. We may feel anxious or depressed. Realizing we are under stress, we do some active problem solving to deal with the demands and regain our equilibrium. We learn and grow from such challenges and develop our resources for meeting future demands.

    But what happens when we get stuck, when the pressure is unrelenting and we seem unable to make headway against the winds of distress? There are times in almost everyone's life when the stress cloud hangs over us longer than usual, the fight-or-flight response becomes a way of life, and we tell our friends we are "stressed out." Prolonged periods of stress, especially negative stress, can contribute to a variety of stress-related disorders. Chronic activation of the nervous and endocrine systems' stress response can affect health in a number of important ways.

CAN STRESS CAUSE ILLNESS?

Concern about the effects of long-term negative stress on physical and mental health is nothing new. In the fifth century B.C., Hippocrates, who has been called the father of medicine, counseled medical students to consider emotional factors in their diagnosis and treatment of disease. Aristotle, the Greek philosopher and scientist who lived from 384 to 322 B.C., believed that body and soul are inseparable and that the emotions play an important role in health and illness. Throughout history, people have observed that hard times and ill health often go hand in hand. We hear about people who become ill and die shortly after the loss of a spouse; we see middle-aged relatives and friends who live high-pressure lifestyles developing heart disease; and when ominous happenings loom on the horizon, we say we are "worried sick." Indeed, stress management students have commented that chronic negative stress feels so bad, it has to be bad for your body as well.

    The relationship between stress and health is not simple. A certain amount or type of stress does not automatically cause a given health condition. The impact of stress on health is mediated by a number of important genetic, environmental, and personality variables. The Student Stress box above illustrates how these variables affect the stress-illness relationship in two students experiencing similar stressors.

    People respond in many different ways to stress. All the variables that make up the stress cycle introduced in the first chapter are important when you are considering the stress-illness relationship. Stress certainly has strong psychological and physical effects, and over time, these can interfere with your health. To add insult to injury, when under excess stress, people may engage in maladaptive coping behaviors, such as smoking and missing sleep, that increase their risk of illness. Illness itself is a form of stress and can exacerbate other stressors (Cox, 1988). Writing a paper with headache is much more stressful than writing a paper when you feel good.

    The manner in which stress is perceived and experienced affects your stress response and thus your health. On the one hand, when a stressor is experienced as uncontrollable, and with an outcome that is expected to be negative, a chronic stress response is more likely to result in health problems (Fisher, 1988; Honzak et al., 1989; Strickland, 1989). When the emotional stress response is negative, you may feel fear, anger, hostility, or alienation; you might feel helpless and hopeless. Such feelings increase your risk of stress-related disorders (Powell et al., 1993; Williams, 1994). On the other hand, the negative effects of stress can be buffered by such factors as an optimistic outlook, some sense of control, a sense of social support, and positive health behaviors (Kobasa, 1979; Scheier & Carver, 1993). Recall the theme of this book-that you can increase your ability to buffer the negative effects of stress in many ways. Doing so can help you prevent or at least reduce the severity of stress-related illness. 

    Having qualified our "yes" response to the question of whether stress can cause illness, let's use the information from Chapter 2 to discover what happens if chronic sympathetic arousal is not balanced by the relaxation response. 

THE CARDIOVASCULAR SYSTEM: HEART AT WORK

Artery Disease

Your cardiovascular system is hard at work when you are responding to stress. Sympathetic arousal and the stress hormones make the heart beat faster and harder. Blood flow is redistributed, blood volume increases, and blood pressure rises. With stress, the blood transports emergency fuel to muscles, so blood sugar, fat, and cholesterol levels increase. Blood clots form more easily. These effects contribute to the development of atherosclerosis, in which the inner walls of the arteries become thickened from deposits of fat, cholesterol, and other substances. (Arteries are the blood vessels that carry blood from the heart to the rest of the body.) Atherosclerosis may develop in any artery. It becomes life threatening when it develops in arteries supplying organs such as the heart or brain, which sustain irreparable damage if deprived of blood for even a few minutes.

FIGURE 3.1 The Coronary Arteries

    Although the heart pumps blood with each beat, it cannot obtain the oxygen and nutrients it needs from the blood that fills its chambers. Like every other organ, the heart has its own arterial system. These are the coronary arteries that "crown" the heart (see Figure 3. 1). Their name comes from corona, the Latin word for crown. Most heart attacks result when blood flow in narrowed coronary arteries stops because of a blood clot or arterial spasm. Coronary artery disease is the leading cause of death in North America. Atherosclerosis in the arteries feeding the brain may contribute to stroke, which is caused by an insufficient blood supply to the brain.

    The development of atherosclerosis and the role played by stress are only partially understood. Researchers believe that this disease begins with some sort of damage to the artery lining. The damage may be caused by many things, including high blood pressure, carbon monoxide from cigarette smoke, high blood cholesterol, and high blood sugar levels. Studies have shown that elevated levels of stress hormones may also damage the lining of arteries. Damaged cells in the arterial lining attract white blood cells that attempt to repair the problem. They move into the artery wall and begin to take up cholesterol from substances circulating in the blood known as low-density lipoproteins (LDLs). These lipoproteins contribute cholesterol after undergoing a process called oxidation, which somehow activates them to become targets for the white blood cells in the artery walls. As part of the repair process, artery cells proliferate and combine with the accumulated cholesterol to form an atherosclerotic plaque, a grayish-yellow mound of tissue inside the artery (see Figure 3.2). As the plaque continues to grow, its rough surface causes platelets, the blood cells that aid in blood clotting, to release hormones that lead to blood clots and more cell growth. Over the years the plaques grow and more blood clots form.

    Atherosclerosis begins early in life; plaque formation has been observed in teenagers and young adults. It is a silent disease in its early stages. Once symptoms such as chest pain become apparent, the disease has already progressed to an advanced state. While atherosclerosis appears to be present in everyone to some degree, it progresses more quickly in some people than in others.

    Atherosclerosis has no simple "cause," and researchers are unable to tell you whether you will have a heart attack because of it. But they can give you your odds. Scientists have been able to isolate risk factors, variables that affect your probability of developing coronary artery disease. Some of these risk factors are unchangeable: age (risk increases with age), gender (males at higher risk until they reach their 60s, when risk is similar for men and women), race (African-Americans have a higher risk), and family history of premature heart attack. Other risk factors can be modified by lifestyle change and appropriate medical intervention. The four strongest modifiable risk factors are high blood cholesterol level, smoking, hypertension, and a sedentary lifestyle.

FIGURE 3.2 The Progression of Atherosclerosis

    What about stress? Does chronic stress contribute to atherosclerosis? Some research has suggested that chronic stress, as measured by the number of recent stressors in a person's life, one's perceived levels of stress, certain personality characteristics, and the nature of one's stress response are all related to risk of artery disease. Stress may contribute to the development of coronary artery disease in several ways.

Changes in Blood Chemistry

Blood Lipids Psychological stress has been shown to raise blood cholesterol levels (Dimsdale & Herd, 1982; Mattiasson et al., 1990). This elevation in cholesterol occurs within minutes of exposure to a stressor and lasts for over 30 minutes (Stoney et al., 1988; Muldoon et al., 1992). Although these increases in cholesterol level are not very large, if sustained over a period of years or a lifetime, they may contribute significantly to the progression of atherosclerosis.

Hemoconcentration and Clotting Part of the explanation for the increase in cholesterol following psychological stress is that the blood becomes more concentrated (Muldoon et al., 1992; Patterson et al., 1993). This effect is known as hemoconcentration. Blood is composed of water and formed elements such as red blood cells, platelets, and white blood cells. With hemoconcentration, there is a greater concentration of formed elements per unit of blood volume due to a loss of plasma (the watery part of the blood) volume. Hemoconcentration is potentially dangerous because it increases the "stickiness" of the blood and the chance of blood clot formation. It is associated with both hypertension and artery disease (Kiyohara et al., 1986; Sorlie et al., 1981).

Blood Sugar Levels Blood sugar levels increase when the body prepares to fight or run away. The effect of elevated blood sugar levels on artery disease is not well understood. Researchers do know that people who have diabetes, and thus poor blood sugar regulation, have an increased risk of artery disease. People with diabetes may be most vulnerable to the effects of stress on blood sugar levels (Goetsch et al., 1993). It is not clear whether such increases pose a risk for others.

Increased Blood Pressure

Hypertension is diagnosed by measuring blood pressure. Health scientists do not know exactly how high is too high, but hypertension is generally diagnosed when systolic blood pressure is greater than 140 mmHg or diastolic blood pressure is over 90 mmHg. About 10 percent of the time hypertension is symptomatic of an underlying disease. Essential hypertension refers to the other 90 percent of the cases in which the cause is unknown. Scientists in developed countries have observed for many years that blood pressure increases with age. At one time it was thought that this increase was a normal part of the aging process, and that a higher blood pressure was essential for adequate circulation in older adults-hence the term essential hypertension. We now know this is not true. People in many cultures do not experience this age-related rise in blood pressure, nor do they experience North America's high rates of heart disease. Hypertension is related to many risk factors, including age, genetics, obesity, alcohol intake, smoking, dietary factors, and a sedentary lifestyle. Stress appears to be a contributing factor as well (Markovitz et al., 1993). Hypertension in turn contributes to atherosclerosis and stroke, although the mechanisms responsible for this association are only partially understood. High arterial pressure may injure the arterial lining and thus initiate and accelerate atherosclerosis.

    Several studies have found an association between stress and hypertension. One interesting study of 264 men examined the association between hypertension and job strain (defined by jobs that had high psychological demands but offered little personal control or decision latitude) (Schnall et al., 1992). The researchers found that job strain was significantly associated with blood pressure, even after they statistically controlled for variables such as obesity, alcohol consumption, smoking, and age. This result suggests that the effect of job strain on hypertension is independent of its effect on other important variables and that job strain has an effect on blood pressure in and of itself This does not imply that the effect of stress on other variables is not important. If stress makes you smoke more, drink more, exercise less, and gain weight, these are still harmful effects. In the study above, researchers also found that job strain interacts with other variables. An interaction is the change in one variable depending on another variable present. Stress had an even stronger effect on blood pressure in men who drank alcohol regularly. This interactive effect is illustrated in Figure 3.3.

FIGURE 3.3
Interaction of Job Stress and Alcohol Use on Blood Pressure
Reproduced with permission. Peter L. Schnall et al., Relation between job strain, alcohol, and ambulatory blood pressure. Hypertension 19:488-494, 1992. Copyright 1992 American Heart Association.

Arterial Injury and Spasm

Stress hormones can damage the arterial lining, initiating and furthering the progression of atherosclerosis, at least in laboratory primates (Manuck, 1995). This finding may explain why some studies have found that stress contributes to artery disease even when other stress-related heart disease risk factors are statistically controlled for. In other words, stress contributes to artery disease in some way or ways in addition to its effects on blood pressure and cholesterol.

    An interesting study from Sweden illustrates this point (Rosengren et al., 1991). This study placed middle-aged men into five groups based on self-reported levels of psychological stress, defined as feeling tense, irritable, or anxious, or having difficulty sleeping. Men in the category reporting feeling the most stressed were 50 percent more likely than the men in the other four groups to experience a heart attack in the following eight years. They were 80 percent more likely to have a stroke. This study is interesting for several reasons. First, stress was measured before disease occurred. You can imagine that a very strong link between stress and illness would be found if you asked people who had just had a heart attack how stressed they were! Second, this study followed 7,000 men-a fairly large sample. Last, the researchers statistically controlled for age and other risk factors such as smoking, hypertension, and high blood cholesterol. This manipulation allowed them to look more closely at the relationship between stress and illness. Their findings indicate that stress affects cardiovascular disease in some way (or ways) in addition to its effects on health behavior, blood chemistry, and blood pressure.

    Stress hormones can also lead to the constriction of arteries damaged by atherosclerosis. Such constriction of already narrowed vessels causes a further decrease in blood flow, which can lead to chest pain, heart attack, or stroke.

    One group of researchers studying this process monitored blood flow in both healthy and diseased arteries as volunteers counted backward by sevens from a three-digit number under time pressure (Yeung et al., 1991). Many subjects showed a typical stress response, which included increases in blood pressure, heart rate, and levels of norepinephrine. The researchers thought that people with a stronger stress response might have greater changes in arterial blood flow, but this was not the case; the intensity of a subject's stress response did not predict blood flow in coronary arteries. Arterial health did. Blood flow in the coronary arteries increased an average of 10 percent in healthy vessels, but decreased an average of 27 percent in diseased arteries. Healthy coronary arteries counter the effect of stress hormones, which tend to narrow arteries, by releasing a substance called endothelium-derived relaxing factor (EDRF). This substance makes the arteries expand so more blood can reach the heart during demanding times. Atherosclerotic plaques appear to interfere with this process (Yeung et al., 1991; Maseri, 1991). So once again we see stress interacting with other factors to cause illness. Combine stress with atherosclerosis and the result may be arterial spasm that causes a dangerous decrease in blood flow.

Irregular Heartbeat

The fight-or-flight response sometimes leads to irregular heartbeats. Most of the time these are not harmful, but in extreme cases, and especially in diseased hearts, these irregular beats can lead to a heart attack (Monagan, 1986). In a healthy heart, all parts of the heart work together in a synchronous fashion. The beat originates from an electrical impulse generated by a natural pacemaker called the sinoatrial node. The upper chambers, the atria, contract first, forcing blood into the two lower chambers, the ventricles, which then pump the blood out through large arteries to the rest of the body. A heart attack occurs when the heart loses this rhythmic beat. When the heart fails to contract in this synchronous fashion, its pumping ability is lost, and a heart attack results.

Changes in Health Behavior

Stress has a negative effect on health if it leads to negative effects on lifestyle. When people feel stressed, they are less likely to stick to their exercise programs, eat well, and get enough sleep. They may be more likely to eat too much and abuse substances such as caffeine, alcohol, and other drugs. The comparison of Jennifer and Tamara illustrates the importance of health behaviors. Although in our story Jennifer just caught a cold, 40 years down the line she would also be more prone than Tamara to high cholesterol levels, hypertension, and artery disease if she does not develop better ways to cope with stress.

STRESS, PERSONALITY, AND CARDIOVASCULAR DISEASE

Intriguing research on personality type and stress response suggests that the way you perceive stress (and life in general) has an important impact on your physical stress response, and your cardiovascular health. Research in the 1950s found that ambitious, competitive individuals who were always in a hurry trying to accomplish a poorly defined set of objectives were more susceptible to coronary artery disease than their easygoing friends (Friedman & Rosenman, 1974). Cardiologists Friedman and Rosenman, who conducted this research, coined the term Type A behavior pattern to describe this "coronary-prone personality." Subsequent research has confirmed that certain components of Type A behavior are especially harmful to one's health. Hostility and anger arising from a cynical distrust of others appear to be most strongly linked to artery disease (Alamada et al., 1991; Dembroski et al., 1989; Julkimen et al., 1994; Williams, 1989). People who score high on psychological tests measuring hostility seem to have higher elevations in stress hormones in response to aggravation and a weaker parasympathetic response; they recover from stressors more slowly. Such people tend to have chronic elevations in the stress hormones and cholesterol. This elevation appears to activate the macrophages, which in turn act with oxidized LDLs to promote the formation of arterial plaque (Williams, 1994). Elevated stress hormone levels are also associated with increases in blood pressure, plaque formation, and arterial spasms. Hostile anger leads to higher levels of testosterone as well. Elevations in testosterone decrease levels of high-density lipoproteins (HDLs), which are associated with slower rates of plaque accumulation and lower heart disease risk.

    Depression is sometimes an effect of chronic stress. Likewise, stress may exacerbate depression that is already present. Depression is characterized by feelings such as hopelessness, helplessness, dejection, and guilt. It is often accompanied by symptoms such as loss of appetite, insomnia, a lack of interest in things that were previously enjoyable, withdrawal from social contacts, difficulty concentrating and making decisions, low self-esteem, and a focus on negative thoughts (Edlin & Golanty, 1996). One interesting study discovered that depression may make a person with other cardiovascular risk factors more prone to heart attack or stroke (FrasureSmith et al., 1993). In this study, plaque buildup was measured in 1,100 men in Finland. Depression did not appear to increase atherosclerosis in men with no risk factors, but it amplified the effect of risk factors in others. For example, depressed smokers had on average 3.4 times the amount of atherosclerosis of nondepressed smokers. Twice as much plaque formation occurred in depressed men with high LDL levels than in nondepressed men with similar LDL levels. Such research underscores the importance of the body-mind-behavior interactions in the maintenance of health and the development of disease.

    Personality variables also appear to be involved in how well people cope with and recover from cardiovascular disease. In an interesting study from McGill University, psychological tests were given to 200 men recovering from heart attacks; the men were then followed for five years. The researchers found that men who reported feeling useless or unable to "do things well" were almost four times as likely to have died during this period (Frasure-Smith, 1989). This study concluded that men with low self-esteem were less able to cope with the stress of heart attack. A subsequent study by the same researchers found that when subjects reporting high stress levels were given help in dealing with their problems, their risk was reduced to that of low-stress patients (Frasure-Smith, 1991).

    Dean Ornish, a pioneer in the use of stress management and other lifestyle modifications for patients with artery disease, believes that psychological factors are important in both the development and treatment of this disease. His is one of several research teams (Hambrecht et al., 1993; Haskell et al., 1994; Schuler et al., 1992) to actually document a decrease in plaque buildup in patients undergoing rigorous programs of exercise, very low-fat diet, and stress management (Ornish et al., 1990). Stress management for Ornish's patients includes at least an hour each day of yoga, breathing exercises, meditation, and imagery. Group support and talking about feelings are an important part of the program. Ornish believes strongly that people's emotions play an important role in the disease process; he urges his patients to "open their hearts" to their feelings, inner peace, to others, and to their higher selves. He emphasizes that a sense of isolation may be the cause of the chronic emotional stress that can contribute to illnesses like heart disease (Ornish, 1990). Other research substantiates these beliefs (Chesney, 1993; Powell et al., 1993; Scheier & Bridges, 1995).

Summary: Stress and Cardiovascular Health

Stress seems to contribute to cardiovascular disease in many ways:

1. Stress may increase levels of blood cholesterol.

2. Stress leads to hemoconcentration and faster clotting rates.

3. Stress contributes to hypertension, which in turn increases cardiovascular risk.

4. Stress hormones damage the lining of the arteries, helping to initiate the process of atherosclerosis.

5. Stress makes unhealthy arteries more prone to spasms that occlude blood flow.

6. Stress may cause irregular heartbeats.

7. Stressful times are often accompanied by changes in sleep, eating, and exercise habits, and use of substances such as caffeine, alcohol, and other drugs

8. Stress may interact with personality variables, such as hostility, feelings of isolation, and low self-esteem, and emotions, such as anger and depression, to increase artery disease.

THE DIGESTIVE SYSTEM: YOUR GUT RESPONSE

Stress and the Digestive System

If someone told you he had "butterflies" or a sinking feeling in the pit of his stomach, or that his stomach felt like it was "tied in a knot," you would know he was talking about the effects stress can have on the digestive system. Many people have abdominal sensations when experiencing a variety of emotions-from anger and hate to love and joy. These sensations are a reflection of our psychophysiological responses to both eustress and distress, which have a significant effect on digestive function and health. For most people, these "gut reactions" are a harmless response; but for some, chronic stress easily upsets the digestive system and can lead to a variety of health problems.

    Recall from Chapter 2 that the digestive system consists of the gastrointestinal (GI) tract, which runs from the mouth to the anus and moves food through the digestive processes; and accessory structures that aid in digestion: teeth, tongue, salivary glands, liver, gallbladder, and pancreas. During the fight-or-flight response, digestion is a low priority; and digestive system function is neglected while the needs of the cardiovascular and musculoskeletal systems are tended to.

    Not everyone develops a digestive problem during periods of chronic stress. Each of us seems to have our "Achilles' heel," our own special areas of vulnerability, in which excess stress manifests itself physically and psychologically. However, digestive complaints are some of the most common stress-related disorders. In addition, many people experience some sort of digestive disorder that seems to be caused by factors other than stress but which can be exacerbated by stress. For example, if you are prone to a "nervous stomach," irritable bowel syndrome, or colitis, a high-stress period can cause a worsening of symptoms. A number of symptoms, discussed next, have been associated with chronic stress.

Gum Disease

Let's start at the top. Many people, including dentists and hygienists, have noticed an association between stress and gum disease (gingivitis). Gum disease results when the gum tissue around the teeth becomes inflamed and bleeds easily. Inflammation is caused by the same bacteria that are responsible for dental caries, or tooth decay. As these bacteria act on sugars, they give off acids that penetrate the tooth's enamel. Other bacteria produce a sticky substance that combines with bacterial and other debris to form dental plaque, which adheres to the tooth surface, especially along the gum line. If plaque is not removed by oral hygiene procedures, such as brushing and flossing, it can build up and harden. Normally, saliva reduces acidity and protects the teeth, but plaque prevents saliva from reaching the surface of the teeth and providing these helpful actions. Plaque also provides a place for bacteria to thrive and inflame gum tissue.

    Why should stress increase gum disease? A variety of hypotheses have been proposed: a reduction in saliva (which can result from stress as well as other factors) favors the growth of harmful bacteria and consequent plaque production; reduction in immune response (to be discussed later in this chapter) may mean a weaker defense against harmful oral bacteria; and oral hygiene and a healthful diet may be neglected during periods of stress. Cigarette smoke contributes to gum disease, so people who smoke more when stressed may experience more gum disease during stressful times.

Esophageal Spasms

Spasm of the smooth muscle of the esophagus produces pain in the chest, which many people mistake for heart attack. These spasms are the result of abnormal peristalsis and are sometimes initiated by gastroesophageal reflux, a condition in which stomach contents escape through the esophageal sphincter. Gastroesophageal reflux may also cause heartburn. Like other gastrointestinal symptoms, esophageal spasms may worsen during stressful times, even though they may be caused by factors other than stress.

Ulcers

Until the development of effective medication, ulcers were the hallmark of "success." Ulcers are sores. Early studies in animals, including those by Selye, found stomach ulcers to be a common stress response, especially when the animals had no control over the stressor (Selye, 1976; Turkhan et al., 1982; Weiss, 1972).

    Why ulcers? The stomach produces a very strong acid, hydrochloric acid, that speeds up digestion by making food more vulnerable to the action of a variety of enzymes. Hydrochloric acid is such a strong acid that it would damage the tissue of the stomach itself if the stomach did not produce a protective mucous coating. It is possible that during stress, norepinephrine causes blood vessels in the stomach lining to constrict, decreasing mucous production. The stomach wall is then vulnerable to the destructive action of hydrochloric acid (Greenberg, 1996). Ulcers may occur anywhere along the gastrointestinal tract but are most common in the stomach and the upper portion of the small intestine.

    It's important to acknowledge that stress is not the only or even the primary cause of ulcers. A bacterial strain, H. pylori, appears to be associated with the development of ulcers in many people. In these cases, ulcers may be treated effectively with antibiotics. An accurate diagnosis and appropriate medical treatment are essential for people with ulcers.

Nervous Stomach and Nausea

Many people experience nausea, a loss of appetite, and stomachaches when feeling stressed. Extreme stress can even lead to vomiting. These stomach symptoms are not necessarily indicative of ulcer development but are painful nonetheless. They may result from some of the same factors that cause ulcers, and in fact, many people with a nervous stomach develop ulcers later in life. These symptoms may also be caused by indigestion or strong spasms of the stomach muscle. Whatever the underlying cause, stomachaches and nausea are messages that something is wrong. People who find that stomach problems signal excess stress are likely to benefit from relaxation techniques that help reduce sympathetic arousal (Davis et al., 1995).

Irritable Bowel Syndrome, Chronic Constipation, and Chronic Diarrhea

Excess stress may alter peristalsis, the rhythmic contractions produced by the smooth muscles of the GI tract. Peristalsis may increase, to produce diarrhea, or slow down, leading to constipation. Symptoms of irritable bowel syndrome include abdominal pain and irregular bowel habits, including constipation and/or diarrhea. Indigestion and excess gas cause some of the pain. So do spastic contractions of the large colon. These conditions are best treated with a combination of diet, exercise, and stress management.

Inflammatory Bowel Disease

Inflanunatory bowel diseases (IBDs) such as ulcerative colitis and Crohn's disease are characterized by an inflammation of the colon (large intestine) and do not appear to be caused by stress; however, most people who have IBDs find that their symptoms get worse when they are feeling stressed. Symptoms of IBDs are abdominal pain with blood (produced by bleeding ulcers present on the colon) and mucus in the stools. Inflammatory bowel diseases may be autoimmune disorders, in which the immune system inappropriately attacks healthy body tissue.

Health Behavior and the Digestive System

Sometimes maladaptive coping behavior provides an additional stress to the digestive system. Drinking countless cups of coffee irritates the stomach and intestines. Alcohol is also an irritant. Smokers have higher ulcer rates than nonsmokers, and their ulcers heal more slowly. When our intake of junk food, which is high in fat and low in fiber, is higher than usual, digestive function will reflect this change. Skipping meals means an empty stomach, which can exacerbate an already irritated stomach lining. Eating well can be a challenge during stressful periods, especially if you experience nausea, loss of appetite, or indigestion. If this is the case, you may need to experiment to find out which foods produce the least amount of symptoms; then vary your eating routine until you find one that works for you.

Summary: Stress and the Digestive System

The GI tract is especially vulnerable to chronic, excessive sympathetic response. Many GI symptoms are caused by stress, and stress can exacerbate preexisting problems and disease. Stress can interfere with peristalsis and other digestive functions, and with immune response. Gastrointestinal problems should be thoroughly evaluated before assuming stress is the culprit. Once a medical diagnosis is made, most GI problems respond well to stress management and relaxation practice, dietary therapy, and appropriate medication.

THE MUSCULOSKELETAL SYSTEM:
STRESS IS A PAIN IN THE NECK

When you imagined the snarling pit bull charging toward you, you felt your muscles brace for action. Initially you froze, but only for a moment until you spun around to run as fast as you could. You may notice a similar bracing response when you face other sources of stress: giving a presentation, organizing a project, or maybe just hearing the phone ring. You probably even brace yourself for fight or flight when you watch an exciting play or movie. Some of the relaxation techniques discussed later in this book will help you learn to become more aware of and reduce excess muscular contraction. Excess muscle tension can cause or worsen several chronic musculoskeletal problems. The most common are discussed next.

Headache

Headaches were once thought to be caused by two different mechanisms. 'tension headaches were attributed to excess tension in the muscles of the head and neck. Vascular or migraine headaches were thought to be triggered by changes in the blood vessels supplying the head. Medical researchers now believe most headaches arise from similar mechanisms involving both muscle tension and vascular changes. A headache is usually called a migraine if symptoms include nausea and vomiting; visual disturbances, dizziness, and confusion; or sensitivity to light, sound, and odor. While most headaches do not reflect serious underlying medical conditions, you should check with your doctor if your headaches are bothering you enough that you take medication more than twice a week, or if they change in frequency, intensity, or duration.

    Headaches begin with some sort of trigger that seems to signal the hypothalamus to initiate the blood vessel and muscle tension problems that cause pain. People with chronic headaches are sometimes able to identify factors that trigger their headache, often with the help of a health behavior diary or stress log. Common triggers are substances in food and beverages, and over- the-counter and prescription medications. Headaches are sometimes related to health behaviors, such as smoking, alcohol and caffeine intake, and sleep deprivation. Stress is one of the most common headache triggers. Fortunately, headaches are very responsive to relaxation training (Sargent, 1982). You can learn to sense the very beginnings of a headache and instruct overactive muscles to relax. Relaxation also appears to change blood flow patterns as well.

Temporomandibularjoint (TMJ) Syndrome

The upper and lower jaw meet at the temporomandibular joint. Movement in this important joint is controlled by five muscles. Important nerves pass through this area. Problems in the functioning of this joint may cause temporomandibular joint (TMJ) syndrome, which is characterized by facial pain, headaches, earaches, and dizziness. The syndrome can be caused by many things: jaw misalignment, bite problems, and injury. The most common (and controllable) cause is teeth clenching and grinding. Stress management and relaxation techniques can help people with TMJ syndrome recognize excess jaw tension and teeth clenching, and assist them in changing their habits (Tasner, 1986). Other treatments include orthodontic adjustments to change jaw alignment and bite.

Back, Neck, and Shoulder Pain

A number of factors, including stress, contribute to back problems. Stress usually causes or worsens back problems by increasing contraction and spasm in vulnerable muscle groups. A spasm occurs when a muscle remains contracted, unable to relax. Excess muscle tension and muscle spasms may restrict blood flow; this leads to lack of oxygen and nutrient delivery and a buildup of waste products. This situation then irritates nerves, which send pain messages to the brain; muscles tighten up even more to "protect" the injured area.

    Muscles in the neck, shoulders, and back are important anti-gravity muscles; during our waking hours they maintain some degree of contraction to keep our bodies from succumbing to gravitational forces (i.e., falling down). We brace these muscles when we move; they help hold us together. Excess tension in them is most likely to cause chronic pain when injury, poor posture, or muscular weakness and tightness make muscles vulnerable to spasm. An overactive stress response often aggravates a preexisting problem. Relaxation training for back, neck, and shoulder muscles can help reduce pain and muscle tension (Lahad et al., 1994; Stoyva & Anderson, 1982). Posture education and exercises to stretch and strengthen postural muscles are also beneficial.

Stress and Injury

During periods of excess stress, people are more prone than usual to accidents and injury (Green, 1985; Williams et al., 1993). Our minds are on our worries, our concentration is poor, and we forget to attend to the task at hand, whether it is driving a car, going down a flight of stairs, or working out in the weight room. Too little sleep and low blood sugar from a poor diet compound the problem.

Summary: Stress and Musculoskeletal Problems

When muscles are continually braced for action, painful muscle tension may develop, and existing musculoskeletal problems may get worse. Areas most vulnerable to such problems are the muscles of the jaw, head, neck, shoulders, and back. People are more prone to accidents during periods of stress.

STRESS AND THE IMMUNE SYSTEM:
THE WALL COMES TUMBLING DOWN 

Psychoneuroimmunology

Subjects in a study designed to evaluate the effectiveness of a pain-killer experience symptom relief after receiving inactive "sugar pill" placebos. People with asthma suffer asthma attacks when they believe they are being exposed to allergens, even though the allergens are purely imaginary. Students experiencing the most psychological stress during exam period come down with more colds than their easygoing friends. Such observations illustrate the powerful connection between our thoughts and our immune system activity.

    The immune system includes the lymph nodes and vessels that run throughout the body and carry immune cells; the spleen, thymus gland, and bone marrow that manufacture immune cells; and the various immune cells circulating in the blood and lymph (see Figure 3.4). At one time physiologists thought the immune system kept to itself, functioning independently without input from other physiological systems. Scientists now know that it communicates extensively with the nervous and endocrine systems (Dantzer & Kelly, 1989; Kiecolt-Glaser & Glaser, 1995). Psychoneuroimmunology (PNI) is the study of the interrelationships of the three body- mind systems that serve as communications networks in the maintainence of health: the nervous, endocrine, and immune systems. Mental states, such as the perception of stress, can affect the synthesis and behavior of various immune cells, including leukocytes and macrophages, types of white blood cells that attack foreign invaders (Futterman et al., 1994; Mills et al., 1995). Immune cells respond to neurotransmitters and hormones and thus communicate with the nervous and endocrine systems. For example, at low concentrations, norepinephrine stimulates the immune system. Cortisol acts to inhibit immune system activity, perhaps one of its energy conservation effects. An elevation in cortisol has been observed in people with depression, so endocrine effects may help explain the link between depression and decreased immune response. Immune cells do not merely eavesdrop; they talk back. They manufacture substances called cytokines that are produced by the brain as well and are believed to act as or interact with central nervous system neurotransmitters (Dantzer, 1989).

    The immune system appears to be the link between stress and a number of stress-related disorders. Some of these involve immune system suppression while others seem to involve an immune system gone awry.

 


Respiratory Infections

Why are students (and teachers) more likely to get sick around exam time? Research has shown that stress might be part of the problem. A depressed immune response means fewer bacteriaand virus-fighting white blood cells and an opportunity for the invaders to gain a foothold in the respiratory system. One group of researchers found that psychological stress was related to an increased risk of upper respiratory infections (colds) in a dose-response manner: more stress, more colds (Cohen et al., 1991).

Herpes

Herpes is caused by a virus, Herpes simplex virus or HSV. The virus can cause cold sores on the mouth, skin rashes, mononucleosis, and genital lesions. Genital herpes is most frequently caused by viral strain HSV-2, while oral herpes is usually caused by viral strain HSV-1, although both viruses can infect both areas. Once a person has been infected, the virus hangs around forever, and symptoms continue to recur from time to time. Herpes is caused by contact with the virus, usually exposure to someone who is "shedding" virus particles. But stress can contribute to the recurrence of symptoms. Some people with herpes have found that they are more likely to develop symptoms during high-stress periods, perhaps because their immune systems are less able to keep the virus in check (Glaser & Kiecolt-Glaser, 1994).

Allergies and Autointinune Disorders

Allergies and autoimmune disorders occur when the immune system responds inappropriately to a harmless substance, such as dust, or to the cells of one's own body. One of the ways the immune system responds to injury and invasion is with inflammation. Several substances contribute to the inflammatory response-for example histamine, which we counter with antihistamines when we suffer from allergies. Inflammation begins with vasodilation of blood vessels and a leaking of fluid into the injured area. This produces redness, heat, pain, and swelling. You have probably observed inflammation if you ever sprained an ankle or other joint, or if you have ever had a skin infection.

    Asthma, allergies, hay fever, rheumatoid arthritis, and many skin disorders, such as eczema and hives are examples of inappropriate immune responses. In asthma, inflammation occurs in the airways; allergic reactions can include inflammation in airways, nasal passages, the skin, and other areas. Rheumatoid arthritis is a chronic inflammatory joint disease and, as mentioned in the section on the digestive system, IBDs involve inflammation of the colon. Scientists do not know exactly what causes the onset of this immune system behavior, what triggers the inflammatory response normally reserved for foreign invaders. Stress does not appear to be the culprit, but it may exacerbate the inflammation in some cases (Farber & Nall, 1993; Fitzpatrick et al., 1990).

Cancer

One of the most controversial areas of psychoneuroimmunology research concerns the role played by stress in the causation and treatment of cancer. Cancer occurs when cells in some area duplicate without normal control and form a tumor that continues to grow, invading and destroying the healthy tissue around it. Many cancer tumors have the ability to spread, or metastasize, to other areas of the body. A few cancer cells will leave the original tumor and travel in the blood stream or lymph and find a new home, where they will initiate a new tumor.

    Cancer begins when something changes a cell's genetic material. Such change is initiated by a carcinogen: a chemical, radiation, or a virus. Stress may trigger carcinogenic changes. Laboratory stressors such as shock have been shown to cause genetic damage in rats (Fackelman & Raloff, 1993).

    How is the immune system involved? Some researchers believe mutant cells are relatively common but are destroyed by immune cells in the early stages before they have a chance to form a tumor. The immune system may also help prevent metastasis by recognizing cancer cells traveling in the blood stream or lymph.

    Now the big question: does stress cause cancer? Although there have been some interesting studies suggesting a possible link, so far there is no clear evidence that stressful life events are associated with increased cancer risk (Cooper, 1988). Suppression of emotion and depression have also been suggested as possible factors that increase cancer risk, but the evidence is fairly tenuous at this point (Brannon & Feist, 1992; Grossarth-Maticek et al., 1982; Schmale & Iker, 1971). Some researchers have suggested that the effects of hostility on macrophages may contribute to cancer as well as artery disease. (The effect of hostility on macrophages was discussed in relation to artery disease.) A few studies have found some association between hostility scores and cancer incidence (Scheier & Bridges, 1995; Shekelle et al., 1983; Williams, 1994). Such research gives us one more reason to increase our stress resistance, but it is important to remember that factors such as exposure to environmental carcinogens (such as tobacco smoke) and genetic vulnerabilities appear to be much stronger as causative triggers than are emotional factors (Cassileth et al., 1985; Eysenck, 1988; Schultz et al., 1994). One review of the literature on stress and cancer concluded that stress may be a contributing factor in less than 10 percent of the cancers in 40- to 60-year-olds (Frank, 1981).

    Now for the other big question: can stress management enhance the efficacy of treatment once cancer has been diagnosed? The use of stress management techniques to help treat cancer has been explored by many, with reports of success (Achterberg, 1985; Simonton et al., 1978). Two well-designed studies have found an association between stress management therapies and improved survival rates in patients with malignant melanoma (Fawzy et al., 1993) and breast cancer (Spiegel et al., 1989). One study found that women who reacted to the stress of a breast cancer diagnosis with resignation had a higher mortality rate than those who responded with denial and a fighting spirit (Greer et al., 1990). And even if stress management is not itself a potent factor in overcoming cancer, it can help people with cancer deal with difficult treatment procedures and make them feel more in control of their lives.

Human Immunodeficiency Virus (HIV)

Acquired immune deficiency syndrome (AIDS) is caused by the human immunodeficiency virus (HIV). The virus is acquired through contact with bodily fluids, such as blood or semen, containing the virus. It may remain latent for many years but eventually causes a decline in immune function, destroying important white blood cells known as CD4 lymphocytes. As the number of these cells declines, the body is less able to fight infections. Victims of AIDS usually die from "opportunistic" infections and cancers that take advantage of the body's weakened state of immunity. Stress is only indirectly implicated in the causation of AIDS if it leads to maladaptive coping in the form of risk-taking behavior such as intravenous drug use with shared needles or unprotected sexual contact.

    Can stress management delay the onset of symptoms or slow disease progression in people infected with HIV? Some studies have suggested that stress management and emotional outlook may affect disease progression, especially in the early stages of infection (Barrett et al., 1994; Burack et al., 1993; Ironson et al., 1994). Increasing stress resistance can help people living with HIV infection cope more effectively with the difficult challenges presented by the illness.

Summary: Stress and the Immune System

Stress may decrease immune response and make people more vulnerable to viral and bacterial infections. Stress may also exacerbate allergies and autoimmune disorders. Stress may lead to cancerous genetic changes, at least in rats. Stress management may enhance the efficacy of medical treatment once cancer is diagnosed. While stress does not cause AIDS, stress management techniques may slow the progression of the disease, at least in its early stages, and help people with HIV infection cope with the disease.

STRESS AND MENTAL HEALTH

Where Does Stress End and Mental Illness Begin?

Like physical health, mental health is not an all or nothing deal but rather a continuum that runs from optimal mental wellness down to extreme mental illness. There is no one point at which someone goes from being "stressed out" to "mentally ill." Someone dealing with schizophrenia or severe depression has an illness caused by something beyond what we commonly experience as stress and needs treatment beyond what stress management programs offer. Most of us, however, fall into that great gray area somewhere between optimal mental wellness and mental illness. All of us are striving to move toward the optimal mental health end of the continuum; stress management helps with this journey.

    The relationship between stress and mental health is a complex one that involves all the components of the stress cycle. Stress interacts with mental health and contributes to several psychological disorders. A psychological disorder is characterized by inappropriate or maladaptive cognitive (thinking), emotional, and behavioral functioning (Brannon & Feist, 1992). Depression and anxiety are the two most common examples of psychological disorders.

Depression

Depression has been the most studied of all psychological disorders. Some studies have related stressful life events such as death of a spouse and divorce to subsequent depression. In general, however, life events alone are not a good predicter of depression. Other research suggests that factors such as vulnerability, perceived coping ability, and social support interact with stressful events to determine whether a person becomes depressed (Revicki & May, 1995). Such research suggests that the effects of stressful life events on mental health are buffered by feelings of control and social support. This should sound like an echo of stress effects on physical health.

Anxiety and Phobias

The relationship of stress to anxiety disorders has a similar echo. Anxiety is a feeling of apprehension. Anxiety disorders are divided into two groups: phobic neuroses and anxiety states. People with a phobic neurosis have an enduring and irrational fear of a specific situation or object, such as taking an exam or flying in an airplane. Anxiety states include panic disoders, generalized anxiety, posttraumatic stress, and obsessive-compulsive disorders. Research has shown a weak connection between stressful life events and onset of anxiety disorder (Brannon & Feist, 1992). Stress can certainly make anxiety disorders worse. Many types of anxiety disorders respond well to stress management techniques along with psychotherapy and medical treatment.

Addiction

Behavioral disorders characterized by addiction appear to be worsened by stress and poor coping skills. Such disorders include alcoholism, eating disorders, and drug addiction (Silvestrini, 1990).

Summary: Stress and Mental Health

Stressful events, a person's interpretations of these stressors, perceptions of vulnerability and the ability to cope with the perceived stressor, and social support variables interact with other psychological and physical variables and contribute to mental health and psychological disorders such as depression and anxiety. Behavioral disorders characterized by addiction, such as alcoholism, eating disorders, and drug addiction, worsen during periods of stress and are exacerbated by poor coping skills.

STRESS AND HEALTH: A FEW MORE THOUGHTS

Research on stress and health appears to justify what many health care workers have observed since the beginning of time: a person's thoughts, feeling, moods, and beliefs influence his or her level of health and the course of disease. Especially harmful appear to be feelings of helplessness, hopelessness, fear, and social isolation-all common to the experience of being sick, and especially to being a patient in a hospital. Preliminary research suggests that psychotherapy and the use of stress management techniques such as positive imagery, relaxation exercises, and humor can help patients feel better and may even have a positive influence on the course of some diseases (Cousins, 1989, 1991; Ornstein & Sobel, 1987). This is not to say that you can live forever by thinking the right thoughts! Also to be avoided is the idea that sick people are somehow "responsible" for their illnesses and would recover if they could only muster up the right attitude. Writer K. B. Alster has noted, "When health is ... believed to be a state achievable by right acts and sufficient will, illness ceases to be a misfortune and is taken as evidence of moral failing" (Alster, 1989, p. 123). Sickness and death are a part of life, much of which is outside our direct control.

    Writer Susan Sontag, who underwent treatment for breast cancer, wrote, "Theories that diseases are caused by mental states and can be cured by willpower are always an index of how much is not understood about the physical terrain of a disease" (Sontag, 1978, p. 55). In the early 1900s, people used to believe strongly in a tuberculosis personality type; now we consider tuberculosis the result of an infectious agent that thrives and spreads in crowded, dark conditions. As our understanding of diseases such as cancer and AIDS grows, the role played by stress, emotional factors, and personality variables will become further illuminated.

    Learning to increase your stress resistance will not guarantee you freedom from physical disease and discomfort; it may not give you one more day of life. It will not erase every worry and fear, but it will probably make you healthier in the long run and certainly happier in your daily life. As you learn to see problems more clearly and regulate your stress response more effectively, you will be better able to weather life's storms and see life's changes as challenges to be met rather than obstacles to be overcome.

SUMMARY

1. Prolonged or intense periods of stress contribute to a variety of stress-related disorders.

2. The impact of stress on health is mediated by a number of genetic, environmental, and personality variables.

3. Stressors experienced as uncontrollable and with an outcome that is expected to be negative are more likely to result in stress-related illnesses than stressors that are perceived as controllable and positive.

4. The nature of one's emotional response to stress has a strong effect on how stress affects one's health. Feelings of anger, fear, alienation, isolation, helplessness, and hopelessness are associated with an increased risk of stress-related disorders.

5. Atherosclerosis begins early in life, and its rate of progression is influenced by a number of factors. The four most important factors under our control include sendentary lifestyle, blood pressure, blood cholesterol level, and cigarette smoking.

6. Stress contributes to cardiovascular disease in many ways: 

a. Stress may increase levels of blood cholesterol.

b. Stress leads to hemoconcentration and faster clotting rates. 

c. Stress contributes to hypertension.

d. Stress hormones damage the lining of the arteries.

e. Stress makes unhealthy arteries more prone to spasms that occlude blood flow.

f.  Stress may cause irregular heartbeats.

g. Stress may lead to maladaptive changes in sleep, eating, and exercise habits as well as increased use of harmful substances such as caffeine, alcohol, tobacco, and other drugs.

h. Stress may increase artery disease by interacting with personality variables such as hostility, feelings of isolation, and low self-esteem as well as emotions such as anger and depression.

7. The gastrointestinal system is especially vulnerable to chronic stress. While most digestive disorders are not caused solely by stress, stress exacerbates these disorders. Examples are gum disease, esophageal spasms, ulcers, nervous stomach and nausea, irritable bowel syndrome, chronic constipation, chronic diarrhea, and inflammatory bowel disease.

8. When muscles are continually braced for action, painful muscle tension may result and existing musculoskeletal problems may worsen. Areas most vulnerable to such problems include muscles of the jaw, head, neck, shoulders, and back.

9. People are more accident prone during periods of stress.

10. Psychoneuroirnmunology is the study of the interrelationships of the nervous, endocrine, and immune systems.

11. Stress may decrease immune response and make people more vulnerable to viral and bacterial infections, such as colds and herpes outbreaks (in people already infected with the virus). Stress may exacerbate allergies and autoimmune disorders.

12. Stress management may enhance the efficacy of medical treatment for some types of cancer.

13. While stress does not cause AIDS, stress management techniques may slow the progression of the disease in its early stages and help people with HIV infection cope with the disease.

14. Mental health is a continuum that runs from optimal mental wellness down to extreme mental illness. Increasing your stress resistance helps y ou move toward optimal mental wellness.

15. Stress contributes to a number of psychological disorders, including depression, anxiety, phobias, and addictions.

16. While one's stress response contributes to one's state of health, it is only one of many factors. We must avoid the notion that sick people are "responsible" for their illness and would recover if only they could muster up the right attitude and manage their stress more effectively.

17. Type A behavior pattern is characterized by hard-driving competitiveness, hostility, a sense of time urgency, and a concern with achievement and acquisition of objects. Cardiologists Friedman and Rosenman found an association between Type A behavior pattern and artery disease, probably caused by chronic overactivation of the fight-or-flight response. Their research in the 1950s began the scientific investigation of the connections between personality variables, stress response, and health.

REFERENCES

Alamada, SJ, AB Zonderman, RB Shekelle, et al. Neuroticism and cynicism and risk of death in middle-aged men: The Western Electric Study. Psychosomatic Medicine 53: 165-175,1991.

Achterberg, J. Imagery in Healing: Shamanism and Modern Medicine. Boston: Shambala, 1985.

Alster, KB. The Holistic Health Movement. Tuscaloosa, AL: University of Alabama Press, 1989.

Barrett, DC, MA ChesneyJ Burack, et al. Letter to the editor. Journal of the American Medical Association 271: 1743, 1994.

Brannon, L and J Feist. Health Psychology: An Introduction to Behavior and Health. Belmont, CA: Wadsworth, 1992.

Burackj DC Barrett, RD Stall, et al. Depressive symptoms and CD4 lymphocyte decline among HIV-infected menjournal of the American Medical Association 270:1568-2573,1993.

Cassileth, BR, EJ Lusk, DS Miller, LL Brown, and C Miller. Psychological correlates of survival in advanced malignant disease? New England Journal of Medicine 312: 1551-1555, 1985.

Chesney, MA. Social isolation, depression, and heart disease: Research on women broadens the agenda. Psychosomatic Medicine 55: 434-435, 1993.

Cohen, S, DAJ Tyrrell, and AP Smith. Psychological stress and susceptibility to the common cold. New England Journal of Medicine 325: 606-612, 199 1.

Cooper, CL. Personality, life stress and cancerous disease. S Fisher and J Reason, (eds). Handbook of Life Stress, Cognition and Health. New York: John Wiley and Sons, 1988.

Cousins, N. Anatomy of an illness (as perceived by the patient). A Monat and RS Lazarus (eds). Stress and Coping. New York: Columbia University Press, 199 1.

Cousins, N. Head First: The Biology of Hope. New York: EP Dutton, 1989.

Cox, T. Psychobiological factors in stress and health. S Fisher and J Reason (eds). Handbook of Life Stress, Cognition and Health. New York: John Wiley and Sons, 1988.

Dantzer, R, and KW Kelley. Stress and immunity: An integrated view of relationships between the brain and the immune system. Life Sciences 44: 1995-2008, 1989.

Davis, M, ER Eshelman, and M McKay. The Relaxation and Stress Reduction Workbook. Oakland, CA: New Harbinger Press, 1995.

Dembroski, TM, JM MacDougall, PT Costa, et al. Components of hostility as predictors of sudden death and myocardial infarction in the multiple risk factor intervention trial. Psychosomatic Medicine 51: 514-522, 1989.

Dimsdale,JE, andJA Herd. Variability of plasma lipids in response to emotional arousal. Psychosomatic Medicine 44: 413-430, 1982.

Edlin, G, and E Golanty. Health and Wellness: A Holistic Approach. Boston: Jones and Bartlett, 1996.

Eysenck, HJ. Personality and stress as causal factors in cancer and coronary heart disease. MP Janisse (ed). Individual Differences, Stress, and Health Psychology. New York: SpringerVerlag, 1988, 129- 145.

Fackelmann, KA, and J Raloff. Psychological stress linked to cancer. Science News 144 (13): 196, Sept 25, 1993.

Farber, EM, and L Nall. Psoriasis: A stress-related disease. Cutis 51: 322-326, 1993.

Fawzy, Fl, NW Fawzy, CS Hyun, et al. Malignant melanoma: Effects of an early structured psychiatric intervention, coping, and affective state on recurrence and survival 6 years later. Archives of General Psychiatry 50: 681-689, 1993.

Fisher, S. Life stress, control strategies and the risk of disease: A psychobiological model. S Fisher and J Reason (eds). Handbook of Life Stress, Cognition and Health. New York: John Wiley and Sons, 1988.

Fitzpatrick, R, S Newman, R Lamb, and M Shipley. Helplessness and control in rheumatoid arthritis. International Journal of Health Sciences 1: 17-23, 1990.

Frank, JD. Holistic medicine: A view from the fence. Johns Hopkins Medical journal 149 (6): 222- 227,1981.

Frasure-Smith, N, and R Prince. Longterm follow-up of the Ischemic Heart Disease Life Stress Monitoring Program. Psychosomatic Medicine 51: 485-513, 1989.

Frasure-Smith, N. In-hospital symptoms of psychological stress as predictors of long-term outcome after acute myocardial infarction in men. American Journal of Cardiology 67: 121-127,1991.

Frasure-Smith, N, F Lesperance, and M Talajic. Depression following myocardial infarction: Impact on 6-month survival. Journal of the American Medical Association 270: 1819-1825,1993.

Friedman, M, and RH Rosenman. Type A Behavior and Your Heart. Greenwich, CN: Fawcett, 1974.

Futterman, AD, ME Kemeny, D Shapiro, and JL Fahey. Immunological and physiological changes associated with induced positive and negative mood. Psychosomatic Medicine 56: 499-511,1994.

Glaser, R, andJK Kiecolt-Glaser. Stress-associated immune modulation and its implications for reactivation of latent herpesviruses. R Glaser and J Jones (eds). Human Herpesvirus Infections. New York: Dekker, 1994.

Goetsch, VL, B VanDorsten, LA Pbert, IH Ullrich, and RA Yeater. Acute effects of laboratory stress on blood glucose in noninsulin-dependent diabetes. Psychosomatic Medicine 55:492-496,1993.

Green, RG. Stress and accidents. Aviation, Space, and Environmental Medicine 56: 638-64 1, 1985.

Greenberg, JS. Comprehensive Stress Management. Dubuque, IA: Wm C Brown, 1996.

Greer, S, T Morris, KW Pettingale, et al. Psychological response to breast cancer and 15-yr outcome. Lancet 336: 49-50, 1990.

Grossarth-Maticek, R, DT Kanazir, P Schmidt, et al. Psychosomatic factors in the process of cancerogenesis: Theoretical models and empirical results. Psychotherapy and Psychosomatics 38: 284- 302, 1982.

Hambrecht, R, J Niebauer, C Marburger, et al. Various intensities of leisure time physical activity in patients with coronary artery disease: Effects on cardiorespiratory fitness and progression of atherosclerotic lesions. Journal of American College of Cardiology 22: 468-467,1993.

Haskell, WL, EL Alderman, JM Fair, et al. Effects of intensive multiple risk factor reduction on coronary atherosclerosis and clinical cardiac events in men and women with coronary artery disease: The Stanford Coronary Fisk Intervention Project (SCRIP). Circulation 88: 975-990, 1994.

Honzak, R, A Veselkova, and Z Poslusny. Personality traits and neurohumoral stress response in healthy young sportsmen. Activitas Nervosa Superior 31: 100-102, 1989.

Ironson, G, A Friedman, N Klimas, et al. Distress, denial, and low adherence to behavioral interventions predict faster disease progression in gay men infected with human immunodeficiency virus. International Journal of Behavioral Medicine 1: 90-105, 1994.

Julkunen, J, R Salonen, GA Kaplan, MA Chesney, andJT Salonen. Hostility and the progression of carotid atherosclerosis. Psychosomatic Medicine 56: 519-525, 1994.

Kiecolt-Glaser,JK, and R Glaser. Psychoneuroirnmunology and health consequences: Data and shared mechanisms. Psychosomatic Medicine 57: 269-274, 1995.

Kiyohara, Y, K Ueda, Y Hasuo, et al. Hematocrit as a risk factor of cerebral infarction: Long-term prospective population survey in a Japanese rural community. Stroke 17:687-692, 1986.

Kobasa, SC. Stressful life events, personality, and health: An inquiry into hardiness. journal of Personality and Social Psychology 37: 1-11, 1979.

Lahad, A, AD Malter, AO Berg, and RA Deyo. The effectiveness of four interventions for the prevention of low back pain. Journal of the American Medical Association 272: 1286-1291,1994.

Manuck, SB, AL Marsland, JR Kaplan, andJK Williams. The pathogenicity of behavior and its neuroendocrine mediation: An example from coronary artery disease. Psychosomatic Medicine 57: 275-283, 1995.

Markovitz, JH, KA Matthews, WB Kannel, JL Cobb, and RB D'Agostino. Psychological predictors of hypertension in the Framingham study: Is there tension in hypertension? Journal of the American Medical Association 270: 2439-2443, 1993.

Maseri, A. Coronary vasoconstriction: visible and invisible. New England Journal of Medicine 325: 1579- 80, 1991 (Nov 28).

Mattiasson, 1, F Lindgarde, JA Nilsson, and T Theorell. Threat of unemployment and cardiovascular risk factors: Longitudinal study of quality of sleep and serum cholesterol concentrations in men threatened with redundancy. British Medical Journal 30 1: 461-466,1990.

Mills, PJ, CC Berry, JE Dimsdale, MG Ziegler, RA Nelesen, and BP Kennedy. Lymphocyte subset redistribution in response to acute experimental stress: Effects of gender, ethnicity, hypertension, and the sympathetic nervous system. Brain, Behavior, and Immuni 9:61- 69,1995.

Monagan, D. Sudden death. Discover, January 1986, 64-71.

Muldoon, MF, EA Bachen, SB Manuck, SR Waldstein, PL Bricker, and JA Bennett. Acute cholesterol responses to mental stress and changes. in posture. Archives of Internal Medicine 152: 775-780, 1992.

Ornish, D. Dr. Dean Ornish's Program for Reversing Heart Disease. New York: Bantam, 1990.

Ornish, D, SE Brown, LW Scherwitz, et al. Can lifestyle changes reverse coronary heart disease: The Lifestyle Heart Trail. Lancet 336: 129-133, 1990.

Ornstein, Rand D Sobel. The Healing Brain. New York: Simon and Schuster, 1987.

Patterson, SM,JS Gottdiener, G Hecht, S Vargot, and DS Krantz. Effects of acute mental stress on serum lipids: Mediating effects of plasma volume. Psychosomatic Medicine 55: 525-532,1993.

Powell, LH, LA Shaker, BAJones, LV Vaccarino, CE Thoresen, andJR Pattillo. Psychosocial predictors of mortality in 83 women with premature acute myocardial infarction. Psychosomatic Medicine 55: 426- 433, 1993.

Revicki, DA, and HJ May. Occupational stress, social support, and depression. Health Psychology 4: 61- 77, 1985.

Rosengren, A, G Tibblin, and L Wilhelmsen. Self-perceived psychological stress and incidence of coronary artery disease in middle-aged men. American Journal of Cardiology 68: 1171-1175,1991.

Rosenman, RH, RJ Brand, CD Jenkins, M Friedman, R Straus and M Wurm. Coronary heart disease in the Western Collaborative Group Study: Final follow-up of 8 1/2 years. journal of the American Medical Association 233: 872-877, 1975.

Sargent, JD. Stress and headaches. L Boldberger and S Breznitz (eds). Handbook of Stress: Theoretical and Clinical Aspects. New York: Free Press, 1982.

Scheier, MF, and CS Carver. On the power of positive thinking: The benefits of being optimistic. Current Directions in Psychological Science 2: 26-30, 1993.

Scheier, MF, and MW Bridges. Person variables and health: Personality predispositions and acute psychological states as shared determinants for disease. Psychosomatic Medicine 57: 255-268,1995.

Schmale, AH, and H Iker. Hopelessness as a predictor of cervical cancer. Social Science and Medicine 5: 95-100, 1971.

Schnall, PL, JE Schwartz, PA Landsbergis, K Warren, and TG Pickering. Relation between job strain, alcohol, and ambulatory blood pressure. Hypertension 19: 488-494, 1992.

Schuler, G, R Hambrecht, G Schlierf, et al. Regular exercise and low fat diet: Effects on progression of coronary artery disease. Curculation 86: 1-11, 1992.

Schultz, R, J Bookwala, J Knapp, et al. Pessimism and mortality in young and old recurrent cancer patients. Presented at the American Psychosomatic Society, Boston, April 15,1994.

Selye, H. The Stress of Life. New York: McGraw-Hill, 1976.

Shekelle, RB, M Gale', AM Ostfeld, et al. Hostility, risk of coronary heart disease, and mortality. Psychosomatic Medicine 45: 109-114, 1983.

Silvestrini, B. The paradoxical stress response: A possible common basis for depression and other conditions. Journal of Clinical Psychiatry 51: 6-8, 1990.

Simonton, OC, S Simonton, andJ Creighton. Getting Well Again. Los Angeles: Tarcher, 1978.

Sontag, S. Illness as Metaphor. New York: Farrar, Straus and Giroux, 1978.

Sorlie, PD, MR Garcia-Palmieri, R Costas, and RJ Havlik. Hemotocrit and risk of coronary heart disease: The Puerto Rico Heart Health Program. American Heart Joumal 101:456-461, 1981.

Spiegel, D, JR Bloom, HC Kraemer, et al. Effect of psychosocial treatment on survival of patients with metastatic breast cancer. Lancet 335: 888-901, 1989.

Stoney, CM, KA Matthews, RH McDonald, and CAJohnson. Sex differences in lipid, lipoprotein, cardiovascular, and neuroendocrine responses to acute stress. Psychophysiology 25: 645-656, 1988.

Stoyva,J, and C Anderson. A coping-rest model of relaxation and stress management. L Boldberger and S Breznitz (eds). Handbook of Stress: Theoretical and Clinical Aspects. New York: The Free Press, 1982.

Strickland, BR. Internal-external control expectancies: From contingency to creativity. American Psychologist 44: 1-12, 1989.

Tasner, M. TMJ. Medical Self-Care, Nov-Dec 1986, 47-50.

Turkkan, JS, JV Brady, and AH Harris. Animal studies of stressful interactions: A behavioralphysiological overview. L Goldberg and S Breznitz (eds). Handbook of Stress: Theoretical and Clinical Aspects. New York: Free Press, 1982.

Weiss, JM. Psychological factors in stress and disease. Scientific American, June 1972, 104-113.

Williams, JM, TD Hogan, and MB Andersen. Positive states of mind and athletic injury risk. Psychosomatic Medicine 55: 468-472, 1993.

Williams, R.B. The Trusting Heart: Great News about Type A Behavior. New York: Random House, 1989.

Williams, R.B. Neurobiology, cellular and molecular biology, and psychosomatic medicine. Psychosomatic Medicine 56: 308-315, 1994.

Wright, L. The Type A behavior pattern and coronary artery disease. A Monat and RS Lazarus (eds). Stress and Coping. New York: Columbia University Press, 1991.

Yeung, AC, VI Vekshtein, DS Krantz, JA Vita, TJ Ryan, P Ganz, and AP Selwyn. The effect of atherosclerosis on the vasomotor response of coronary arteries to mental stress. New England Journal of Medicine 325: 1551-1556, 1991.