14.3 - stress and illness

1. Psychophysiological Disorders

• Definition: Physical disorders or diseases whose symptoms are either caused, triggered, or worsened by stress and emotional factors.

• Symptoms are real and physiological but influenced heavily by psychological stress (hence “psycho” + “physiological”).

• Examples include:

  • Cardiovascular disorders: Hypertension, coronary heart disease.

  • Gastrointestinal disorders: Irritable bowel syndrome.

  • Respiratory disorders: Asthma, allergies.

  • Musculoskeletal disorders: Low back pain, tension headaches.

  • Skin disorders: Acne, eczema, psoriasis.

• Personality and Illness:

  • Disease-prone personality traits: depression, anger/hostility, anxiety.

  • Neuroticism linked to chronic health problems and mortality risks.

2. The Immune System and Stress

• Role of Immune System:

  • The body's defense system against harmful microorganisms (bacteria, viruses, fungi).

  • Includes various cells (e.g., lymphocytes), organs (thymus, bone marrow, spleen, lymph nodes), and mechanisms to identify and destroy pathogens.

• Immune System Errors:

  • Autoimmune diseases: Immune system attacks own healthy tissues (e.g., rheumatoid arthritis, lupus, Hashimoto's hypothyroiditis).

  • Immunosuppression: Reduced immune function making one susceptible to infections

  • Example: AIDS—caused by HIV, destroys antibody-producing cells.

• Psychoneuroimmunology:

  • The study of how psychological factors like stress influence immune function.

  • Originated from findings such as classical conditioning of immune responses in animals.

• Impact of Stress on Immune Function:

  • Chronic or intense stress weakens immune response, reducing lymphocyte production.

  • Stress-related hormones (especially cortisol) impair immune defense.

  • Research shows stressors such as public speaking, exams, divorce, caregiving, and harsh climates consistently reduce immune effectiveness.

  • Experimental exposure to viruses demonstrated higher infection rates among individuals reporting chronic stress.

  • Chronic stress slows wound healing by suppressing immune proteins.

• Example Studies:

  • Volunteers exposed to cold virus more likely to develop colds if under chronic stress.

  • Alzheimer’s caregivers showed poorer antibody responses to vaccinations.

  • Stress reduces immune proteins critical for skin wound healing.

• Stress and Cellular Aging:

  • Chronic stress accelerates telomere shortening in DNA, associated with aging and disease risk.

  • Stressed caregivers and individuals exposed to early-life adversity have significantly shorter telomeres, biologically aging faster.

3. Stress and Cardiovascular Disorders

• Cardiovascular System: Includes heart and blood vessels; vital to circulation and health.

• Cardiovascular Disorders:

  • Common types: Hypertension (high blood pressure), coronary heart disease, heart attacks, strokes.

  • Symptoms: Chest pain (angina), shortness of breath, discomfort radiating to arms, neck, jaw, back, nausea.

  • Hypertension is called “the silent killer” — often asymptomatic but increases risk of serious events.

• Risk Factors:

  • Biological: Aging, obesity, diabetes.

  • Behavioral: Poor diet, smoking, inactivity, excessive alcohol.

  • Social: Low income, education, job stress.

• Stress-Related Contributions:

  • Job strain, natural disasters, marital conflict, chronic noise, and perceived discrimination raise blood pressure and contribute to heart disease.

  • Experimental stress tasks increase blood pressure during the task.

• Personality and Heart Disease:

  • Type A Behavior Pattern:

    • Competitive, time-urgent, impatient, hostile.

    • Early studies linked Type A to heart disease, but later research refined this to hostility/anger as the critical component.

  • Hostility Cycle:

    • Hostile thoughts and feelings → antagonistic behavior → negative social reactions → reinforced hostility.

    • This social strain promotes cardiovascular risk.

• Other Emotional Factors:

  • Negative affectivity: Chronic experience of negative emotions (anger, fear, guilt) associated with hypertension and heart disease.

  • Depression: Strongly linked to increased incidence and mortality of heart disease.

    • Depressed individuals have a higher risk of heart attack.

    • Depression screening is now recommended for heart patients.

• Mechanisms Linking Emotional Factors and Cardiovascular Disease:

  • Negative emotions cause chronic physiological arousal.

  • They induce social strain and stress responses harmful to cardiovascular health.

  • Depression may promote unhealthy behaviors (smoking, inactivity, obesity), increasing risk.

• Summary of Key Findings:

  • Anger and hostility are potent predictors of heart disease.

  • Psychological risk factors (depression, anxiety, hostility, anger) have additive effects on cardiovascular risk.

  • Depression increases cardiovascular mortality and morbidity substantially.

4. Stress and Other Psychophysiological Conditions

• Asthma:

  • Stress can exacerbate asthma attacks via immune and inflammatory pathways.

• Tension Headaches:

  • Stress-induced muscle tension and neurological changes contribute to headache development.

Summary Table: Stress-Related Health Effects

1. Asthma

• Definition:

  • Chronic disease characterized by obstruction and inflammation of the airways in the respiratory system.

  • Inflammation thickens airway walls; muscles around airways tighten, narrowing airways and obstructing airflow.

  • Results in difficulty breathing, wheezing, chest tightness, shortness of breath, and coughing (especially in morning and night).

• Prevalence and Impact:

  • Affects approximately 18.7 million U.S. adults; more common among lower-income populations.

  • Increasing prevalence (157% rise from 2000 to 2010).

  • Annually, ~4,000 deaths directly due to asthma, with asthma contributing to another ~7,000 deaths.

• Triggers/Exacerbating Factors:

  • Environmental: air pollution, allergens (pollen, mold, pet dander), cigarette smoke, infections, cold air or temperature changes, exercise.

  • Geographic "asthma alleys": neighborhoods with high pollution due to factories, trucking, power plants (e.g., Long Beach, CA; Bronx, NY).

• Psychological Factors and Asthma:

  • Psychological stress and emotions directly influence immune and respiratory functions, serving as common triggers for asthma exacerbation.

  • Asthma-like symptoms can occur in patients who expect to experience symptoms even when exposed only to inert substances.

  • Asthma sufferers tend to experience higher levels of negative emotions such as anxiety; asthma attacks correlate with heightened emotional states.

  • Studies linking emotional distress and negative affect to increased airway obstruction and self-reported asthma symptoms.

• Case Study Insight:

  • An 18-year-old with asthma experienced symptoms triggered by Facebook activity related to emotional distress from a breakup, suggesting social media stress as a modern exacerbating factor.

  • Psychological distress linked to asthma onset/development in children and adults, with parenting difficulties and interpersonal conflicts increasing risk.

2. Headaches

• General Definition:

  • Continuous pain located anywhere in head/neck region.

• Types of Headaches:

  • Sinus headaches: Due to sinus inflammation/infection or allergies; pain localized to cheeks and forehead.

  • Migraine headaches: Characterized by severe pain (unilateral or bilateral), nausea, disturbed vision; more common in women.

  • Tension headaches: Triggered by facial/neck muscle tension; most common worldwide (~42% prevalence).

• Tension Headaches:

  • Affect over one-third of U.S. population yearly; 2–3% suffer chronic forms.

  • Triggers include:

    • Sleep deprivation

    • Skipping meals

    • Eye strain

    • Physical overexertion

    • Poor posture-related muscular tension

    • Stress

• Psychophysiological Connection:

  • Stress increases pain sensitivity, especially in tension headache sufferers who have generally lower pain thresholds.

  • Tension headache sufferers report higher subjective stress during stressors.

  • Stress may contribute by amplifying pain signals along already sensitive pathways.

3. Psychological and Stress-Related Influence on Asthma and Headaches

• Psychological distress and emotions can trigger or worsen asthma and tension headaches by:

  • Modulating immune and respiratory functions: Stress hormones and emotional states can exacerbate airway inflammation and obstruction.

  • Increasing pain sensitivity: Stress amplifies pain perception, lowering thresholds, particularly in tension headache sufferers.

  • Expectancy effects: Belief or expectation of symptoms can evoke real physiological manifestations (e.g., asthmatic response to inert substances).

• Emotional distress is a potent contributor to the severity and frequency of asthma attacks and headaches, highlighting the importance of integrating psychological management in treatment plans.

Summary Table