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Stress, Coping, and Adaption. March 17, 2008 Stress, Illness, and Disease. Eric Weiser. Curry College. Overview. Intro History Coping and Health Theories of the Stress-Illness Link Biological Theories Fundamentals of the Immune System Psychological Theories Cardiovascular Disorders
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Stress, Coping, and Adaption March 17, 2008 Stress, Illness, and Disease Eric Weiser Curry College
Overview • Intro • History • Coping and Health • Theories of the Stress-Illness Link • Biological Theories • Fundamentals of the Immune System • Psychological Theories • Cardiovascular Disorders • Essential Hypertension • Coronary Heart Disease • Asthma • Managing Psychophysiological Disorders and Stress
Introduction • Psychophysiological disorders (also known as psychosomatic disorders) are genuine physical disorders can be caused by or worsened by stress and emotional states • Recognizes a broad range of diseases involving the circulatory, respiratory, digestive, and central nervous systems • Ulcers • Hypertension • Coronary heart disease
Brief History • Franz Alexander • The “Father of Psychosomatic Medicine” • Believed that psychosomatic disorders are tied to unconscious conflicts • Ulcers • Tied to oral conflicts • Asthma • Symbolic “cry for mother’s breast” • Hypertension • Unreleased anger (Anger-In Theory) 1891-1964
Brief History • In the 1970s, the fields of behavioral medicine and health psychology exploded • Behavioral medicine • Interdisciplinary approach involving medicine and behavioral science • Goals • To understand, prevent, and treat illnesses influenced by psychological factors • Health psychology • Branch of psychology concerned with role of psychological factors in health and illness
Coping and Health • Coping • Attempts to deal with problems and negative emotions elicited by stressors • Two dimensions • Problem-focused coping • Taking action to solve problem • Emotion-focused coping • Making efforts to reduce negative emotional reaction • Avoidance coping • Avoid acknowledging problem • Neglecting to do anything to solve it
Coping and Health • Other types of coping • Use of humor • Distraction • Social support • Disengagement (i.e., “giving up”) • Effective coping varies by situation • Distraction may be adaptive in some situations (chronic pain) and maladaptive in others (financial problems)
Coping Orientations to Problems Experience (COPE) Scale • Measures the type of coping strategies used to handle recent stressors • Scales and sample items from the COPE are on the right • Carver et al. (1993) • Studied coping methods of women with breast cancer • Humor linked to less distress • Avoidant coping strategies (e.g., denial, behavioral disengagement) linked to more distress
Social Support • Social support is generally thought of as the “soothing effect of friends, family, and acquaintances.” • Components of Social Support(Weiss, 1974) • Attachment • Guidance • Tangible assistance • Embeddedness • Reassurance of self-worth • Opportunity to provide nurture
Social Support and Health • Types of social support • Structural • Networks of social relationships • Number of friends, marital status, etc • Functional • Quality of social relationships • Friends, family supportive and there when needed
The Buffering Hypothesis • Assumes that social support will provide the greatest benefit only in times of stress
Theories of Stress-Illness Link • Most involve both psychological and biological factors • Much research limited by self-report data • Stress-illness link mediated by: • Changes in health related behaviors • e.g., smoking, substance abuse, lack of exercise • Changes in physiology • e.g., cardiovascular reactivity, reduced immune system functioning • We will now look at biologically based and psychologically based theories of the stress-illness link
Biologically Based Theories • Allostatic Load • The physical damage caused by prolonged exposure to stress hormones (e.g., cortisol) • Damage to cells in hippocampus (regulates cortisol secretion) • Impaired immune system functioning • Increased susceptibility to disease • Stress and the immune system • Stress has a deleterious effect on immune function • Psychoneuroimmunology • Study of how behavioral and psychological factors impact immune system • Has been a growing area since the 1980s
Psychoneuroimmunology • Janice Kiecolt-Glaser (pictured) of Ohio State University is a major figure in the field of psychoneuroimmunology. • During the 1980s, she did some pioneering work demonstrating that stress has a deleterious effect on the immune system. • Medical school exams • Relationship discord • Depression and bereavement • Caring for a relative with Alzheimer’s Kiecolt-Glaser
Immune System: Fundamentals • Immune system • Collection of cells, proteins, and mechanisms that respond when the body is infected or invaded by foreign substances that can damage organs and tissues • These foreign substances are known as antigens • Possesses a memory, in the sense that it can remember encounters with foreign substances • Subsequent encounters with these antigens induce a more rapid and potent response
Immune System: Fundamentals • Two types of immunity: • Natural (innate) immunity • Immunity present at birth, and works very general way • Involves skin, as well as certain cells (macrophages and natural killer cells [NK cells]) which stimulates immune response • First and second lines of defense • Specific (acquired) immunity • Involve cells that respond more slowly to infections, such as lymphocytes (white blood cells) • T-helper and B cells • Third line of defense
Immune System: Main Network • Lymph nodes • Small, oval-shaped structures that are located throughout the body, they are an important part of the immune system • They produce cells to help fight infection and disease
Immune System: Big Players • Lymphocytes • White blood cells generated in various sites such as lymph nodes, bone marrow, spleen, thymus, appendix, etc. • T cells • Produced in the thymus; kill virus and cancer cells • Release chemical messengers known as cytokines (e.g., interleukin) that facilitate immune response • B cells • Produced in bone marrow • They produce antibodies, which are protein molecules that kill (lyse) bacteria and prevent infection • The antibodies they produce are called immunoglobulins, and are found in the bodily secretions (e.g., saliva, tears, mucus). An example is IgA
Variations of T Cells • Helper-T cells • These cells “help” in the immune process by inducing B cells to produce antibodies and by activating killer-T cells • Memory-T cells • Cells that “remember” and identify antigens, which initiates a rapid response if the antigen is encountered again • That’s why we develop immunity after exposure; memory-T cells “remember” • Killer-T cells • “Killers” that work with the helper-T cells • Suppressor-T cells • Cut off the immune response to regulate it • Announce that “the battle is over,” as immune defenses move back into a state of routine surveillance
Immune System: Fundamentals • When T cells notice an invasion, white cells divide and multiply • Thus, one sign of a healthy immune system is speedy white blood cell growth
Immune System: Fundamentals • NK Cells • Cells that can kill on their own without the assistance from helper T cells • Have a natural affinity for tumor cell and viruses that does not depend on prior exposure • Phagocytosis • Utulizes cells known as phagocytes to absorb and destroy pathogens (any harmful invaders) • An important variety of phagocytes are cells called macrophages (from bone marrow) • Both NK cells and phagocytosis are components of natural (innate) immunity
Macrophage A large macrophage (top) is about to trap and “munch” a tiny bacterium (lower right). Macrophages constantly patrol the body for invaders, such as this Escherichia coli, bacterium, and for debris, such as worn out red blood cells.
Immune System: Fundamentals • Cellular immunity • Refers to immune function at the cellular level • That is, refers to the workings of the T cells • e.g., growth of helper T-cells, killer-T cells, antibodies, etc for new and unrecognized antigens • Can take days or weeks • Humoral immunity • Refers to immune function at the level of bodily secretions (saliva, mucus, tears) • That is, refers to the workings of the B cells and their antibodies • Works very fast
Measuring Immunity • Very challenging to measuring the functioning of the immune system • Cells come from the thymus, lymph nodes, bone marrow, appendices, etc, but there’s no way to measure action in these sites • However, there are various ways we can measure immune functioning in vivo (in the body) and in vitro (in glass test tubes)
Measuring Immunity • Flow Cytometry • Measure overall level of T cells in blood • Lymphocyte counts • Measure of antibody development to latent viruses • About 95% of U.S. adults have been infected with the Epstein-Barr (herpes) virus (EBV) at some point in their lives • Lies dormant (latent) as the immune system holds it in check, but can be reactivated by illness or stress • Through blood samples, you can detect if the virus is becoming reactivated, as well as how well antibodies are proliferating and fighting the virus (should have lower antibody development, or titers); less is more • Measure of NK cytotoxicity • In vitro, mix NK cells with radioactive tumor cell • Release of radioactivity (measured by gamma counter) by tumor cell indicates of how well NK cells are functioning
Measuring Immunity • Mitogen-induced lymphocyte proliferation • This is a measure of cell division (in vitro) • The goal is to determine how well new lymphocytes can proliferate when stimulated by a mitogen (something that stimulates cell division). The approach is as follows: • New cell division requires new DNA for each cell • New DNA requires an enzyme called thymidine, which is “sucked up” by the creation of the new cell • Mix T cells with a mitogen (usually a plant extract like ConA or PHA) and radioactive thymidine • Mix, wait, and then measure how well the new cells incorporate the radioactive thymidine into DNA (measure with a beta counter, used in radiation detection)
Immune System: Fundamentals • If stress in some way impacts the immune system, there should be a demonstrable connection between the central nervous system (CNS) and the immune system. • Studies looking at the classical conditioning of the immune response demonstrate that, indeed, just such a connection exists.
Ader & Cohen (1975) When rat’s drinking of saccharin-sweetened water was paired with injections of an immunosuppressive drug, after repeated pairings the sweetened water alone triggered immunosuppression, as if the drug had been given.
Psychological Stressors and Immunity • Bartrop et al. (1977) • Decreased lymphocyte production in bereaved spouses (compared to nonbereaved spouses) • Kiecolt-Glaser et al. (1987) • 16 separated women (1 year or less) showed poorer immune function (lymphocyte counts) compared to controls • Kiecolt-Glaser et al. (1988) • Separated and divorced subjects had better immune function if they initiated the separation
Psychological Stressors and Immunity • Kiecolt-Glaser et al. (1993) • As 90 healthy newlywed couples spent ½ hour discussing problem areas in their marriage, some expressed more anger and hostility during the discussion • These subjects had worse immune functioning the next day (e.g., worse responses to ConA and PHP, higher antibody titers to Epstein-Barr virus, etc) • Kiecolt-Glaser et al. (1984) • Med students have lousy immune function (decay in NK cells) 1 month before major exams
Psychological Stressors and Immunity • Secretory immunoglobulin A (sIgA) • Present in secretions of body’s mucosal surfaces • That is, in tears, saliva, and in nasal, vaginal, and bronchial secretions Found in these secretions • Contains antibodies that guard against viruses and bacteria • Link between sIgA and mood (Stone et al., 1987) • Increased negative mood → reduced sIgA
Psychological Stressors and Immunity • Problem • All the studies just described were correlational • Correlation does not imply causation • Maybe only the weak, the stupid, and the unworthy get fired, disliked, divorced, and separated. If so, weakness could be the real cause of low immunity. Or, poor immunity causes low friendship, getting fired, divorced, or separated (e.g., “He’s too sick…I’m out of here!”) • We need experiments (random assignment to conditions • This has been done, but mostly with animal studies
Psychological Stressors and Immunity • Laudenslager et al. (1988) • Decreased IgA antibody production, NK cell activity, and lymphocyte production in response to electric shocks • Cohen et al. (1992) • 43 monkeys, 21 of which were housed with 3 or 4 new monkeys (disrupted colonies) • Compared to monkeys left in stable groups, the socially disrupted monkeys exhibited weaker immune function • Vessey (1964) • Placing socially isolated mice in group setting for 4 hours/day (social disruptions) resulted in lower antibody responses to mitogen
Stress and Colds • Cohen et al. (1991) • Subjects infected with cold virus • Completed measures of stress • Higher stress associated with greater chance of developing a cold
Immune System: Summary • So, clearly, various psychosocial stressors (both in lab and in real life) hurt immune function • Areas in which more work is needed: • Better measures of immune function • A better understanding of the impact of short-term stressors (e.g., daily hassles) on the immune processes • e.g., what cumulative effect do daily hassles have on immune function? • The impact of stress reduction techniques on the immune system, especially during times of major stress (e.g., spouse dying in hospital) • In terms of fully understanding the connection between stress and immune function, we are still a “long way from home”
Psychological Theories of Psychophysiological Disorders • Psychoanalytic • Anger-in theory (Alexander, 1950) • Unexpressed hostility → negative emotions which impact health • Cognitive • Distressing thoughts → negative emotions (worry, regret, resentment) → sustained sympathetic nervous system activity • Personality • Link between chronic negative emotion and cardiovascular disease, reduced immune system functioning • Optimism linked to enhanced immune system functioning
Cardiovascular Disorders • Diseases involving heart and blood circulation system • Two cardiovascular disorders affected by stress: • Essential hypertension • Coronary heart disease (CHD)
Essential Hypertension • Hypertension • High blood pressure • Increases risk for: • Heart attack, stroke, atherosclerosis (clogged arteries) • Essential hypertension • Hypertension without biological cause • 90% of all hypertension is essential
Systolic pressure Arterial pressure when the ventricles contract and the heart is pumping Diastolic pressure Arterial pressure when the ventricles relax and the heart is resting Normal levels 120 systolic 80 diastolic High levels 140 or higher systolic 90 or higher diastolic Essential Hypertension
Stress and Blood Pressure • Stressful conditions (lab tasks) produce a short-term increase in blood pressure • Negative mood induction, cold pressor test, giving a speech, mental arithmetic, etc. • These increases return to baseline when the stressor is withdrawn • Unethical to test whether short term lab induced BP increases lead to prolonged hypertension
Stress and Blood Pressure • Ambulatory studies of BP are used to get a better understanding of the relationship between stress and BP in people’s natural environments • Shapiro, Jamner, & Goldstein (1993) • Paramedics wearing BP cuffs reported BP during high and low stress calls • BP was higher during high stress vs. low stress calls • However, BP was higher on high-stress calls for paramedics who had anger-prone and defensive personality traits • Shows that personality factors are linked to how people respond to stressful situations
Psychological Risk Factors for Essential Hypertension • Anger • In men • Angering easily • In women • Anger suppression • Type A behavior (Friedman and Rosenman) • Three components • Achievement striving/competitiveness • Urgency/impatience • Hostility
Biological Risk Factors for Essential Hypertension • Cardiovascular reactivity • Extent to which BP and HR increase in response to stress • Influenced by heredity • Everson et al. (1996) • Longitudinal (4-year) study of 508 Finnish men whose BP reactivity had been earlier assessed (via anticipated a bicycle exercise test) • Those whose BP had increased 30 pts or more were four times more likely to have developed hypertension 4 years later
Coronary Heart Disease • Two forms • Angina pectoris • Intermittent chest pain caused by insufficient oxygen to heart (ischemia) • Often caused by atherosclerosis • Arterial clogging of blockage • Can also be triggered by physical exertion or stress • Myocardial infarction (heart attack) • Also caused by insufficient oxygen to heart • Total blockage of coronary artery • Often results in permanent heart damage
Risk Factors for Coronary Heart Disease (CHD) • Age • Cigarettes • Diabetes • Elevated BP or serum cholesterol • Alcohol • Obesity • Lack of exercise • Sex (men more likely to have CHD)
Psychological Risk Factors for Coronary Heart Disease (CHD) • Stress • Acute and chronic • Job strain • Excessive work load, lack of control over decision making, no opportunity to fully use one’s skills • Of these factors, it appears that lack of control in what you do in the job is perhaps the most significant factor • Marmot et al. (1997) • A 5-year longitudinal study of over 10,000 British civil servants • Those with low-status jobs (e.g., postal clerk) were more likely to develop CHD • Low status in this case refers to having little control while on the job