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Stress. Jeffrey P Schaefer MSc MD FRCPC February 7, 2007. Objectives. Medical Aspects of Stress What is stress? Stress Hormones and Actions Allosteric Load Effects of Stress Strategies to Reduce Stress. What’s Stress Popular Definition. “Not enough time…” . Acute Stress Response.
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Stress Jeffrey P Schaefer MSc MD FRCPC February 7, 2007
Objectives Medical Aspects of Stress • What is stress? • Stress Hormones and Actions • Allosteric Load • Effects of Stress • Strategies to Reduce Stress
What’s Stress Popular Definition • “Not enough time…”
Acute Stress Response • The body’s adaptive response to stress. • flight or fright response See Grizzly Bear See Dick Run See Jane Run Run, Run, Run…
Hans Selye (1907-1982) General Adaptation Syndrome • observed effects of negative events he called ‘Stressors’ Stress • Proposed 3 phase to chronic stress: • alarm prepare for ‘flight / fright’ • adaptation resistance to stress • exhaustion inability to cope
The ‘un-stressed’ state… • Homeostasis: • A balanced and stable internal environment.
What is stress? • Stress is determined by the balance between perceived demands of the environment and the individual’s resources to meet those demands.
Stress – not just psychological • Stress 4 components • the stress stimuli • the experience of stress • the physiological stress response • the experience of the stress response
Recipe for Stress What makes things Stressful? • Novelty • Unpredictability • Threat to ego • Sense of loss of control
Categorizing Stress • Absolute Stress • threat to life • earthquake, fire, physical attack…
Categorizing Stress • Relative Stress • implied threat based on interpretation
Eustress vs Distress • Eustress – good stress • Distress – bad stress • Cognitive Interpretation of Events effects our interpretation of events. “Challenge vs Opportunity’
Stress Hormones • Corticosteroids • Cortisol • Catecholamines • Adrenaline (Epinephrine) • Nor-adrenaline (Nor-epinephrine)
Cortisol Regulation • Brain • emotion, pain, memory • Hypothalamus • autonomic function • Pituitary • stimulating hormone • Adrenal Gland • cortex
Cortisol Acute Effects • Response to Absolute Stress • increase vigilance • respond to emotion don’t think • raise blood sugar • increase psychomotor activity • obtain food
Prolonged Cortisol Effects • bone calcium loss • muscle wasting • insomnia • irritability • depressed mood • memory loss* • immune dysfunction • 2006 > Negative fx • increase appetite • increase blood sugar • increase fat stores • redistribute fat • salt retention BP + • thinning of skin • reduce acid barrier • interferes with menstrual cycle • male impotence
Disease States • Moon facies
Catecholamines • Adrenaline (Epinephrine) • Nor-adrenaline (Nor-epinephrine)
Effects of Catecholamines • increase heart rate • increase cardiac force of contraction • narrows blood vessels • increase blood pressure • dilates pupils • dilates airways • reduces flow of blood to GI tract • reduces saliva production • increases platelet adherence ‘stickiness’ • increases sweat production
Prolonged Catecholamine • Pheochromocytoma • hypertension • cardiac disease • vascular disease
Allosteric Load • Allostasis (flight or fight response) • ‘good stress’ gets us out of trouble • Chronic Stress • when we don’t ‘get out of trouble’
Allosteric Load Stress Related Disease Disease Related Stress • Headache • Irritable Bowel Syndrome • Obesity Diabetes Osteoarthritis • Regional Pain Syndromes & Fibromyalgia • Chronic Fatigue
What does the literature show? • Acute Stress & Chronic Stress • studies of people (not test tubes)
Acute Stress in Heart Attack • Mortality in Widowers • 40% increase within 6 mo of spouses death • Myocardial Infarction Onset Study • among heart attack victims, there was a 14 times increase in death of significant person last 6-12 mo • INTERHEART Study • 11,000 first MI vs 13,000 matched controls 52 countries • Stress Events • 16.1% vs 13.0 % (OR 1.48; 95% CI 1.33-1.64) • marital separation or divorce, loss of job or retirement, loss of crop or business failure, violence, major intrafamily conflict, major personal injury or illness, death or major illness of a close family member, death of a spouse, or other major stress.
Chronic Stress and Disease • Cohort of 13,609 mean age 45 yr measured chronic stress • High 15% Risk of first MI, Stroke, ACS 14% higher men • Mod 6% • Low 80% • Social isoation, self-blame, and avoidance higher in a group a 130 MI patients when compared to 102 controls
Selected Factors Hostility • Hostility was measured in 1,877 employed men • Observed 10 year incidence of MI / CHD death • Adjusted for age, bp, chol, cig use, etoh Results • 42% increase in death from lowest to highest quintiles • Risk of death / MI was 0.68 for low score group
Chronic Stress & Immune Dysfunction • Care Giver of Dementia Pts • 50 spouses • 67 controls • Emotional distress higher in care givers • Salivary Cortisol levels higher in care givers
Chronic Stress & Immune Dysfunction • Influenza Vaccination • 3 strains • 1 strain difference • 2 strains no difference • Lancet 1999
Wound Healing • Lancet 1995 • Punch Biopsies • 13 Care Givers vs 13 Controls • Complete wound healing • Caregivers 48.7 vs 39.3 days (9 day diff) • Age and income did not effect outcome
So now what? • Remember, our body does not understand that’s it’s 2006 AD, not 2006 BC
Dr. Sonia Lupien • Work on yourself • methods of resolving problems • learn to appreciate others • learn to appreciate yourself • practice goodwill • Work on your Body • breathe • move • power of laughter and smiles
Solving Problems • Avoid Avoidance • may work in short term • negative in the long term
Two Basic Responses to Problems • Emotional Response • primary instinct biological factors • danger of incorrect interpretation • predisposes to hostility • risk factor for CV disease • Cognitive Response • analyze • problem solve • gain control
Goodwill • Mother Theresa Effect • improved self-esteem
Recognize the Source of Stress • Novelty • Unpredictability • Threat to Ego • Sense of Loss of Control Have a Plan B
Summary • Stress is physiological / psychological • Novelty, Unpredictability, Threat, Control • Hormones are the stress messengers • Allosteric load has negative consequences • Strategies to reduce stress are important