Stress and Disease Class Notes PDF

NURS 7053 - Advanced Pathophysiology I for DNP Students Stress and Disease - Class Notes Stress A condition in which a demand exceeds a person’s coping abilities, resulting in disturbances of cognition, emotion and behav...

NURS 7053 - Advanced Pathophysiology I for DNP Students Stress and Disease - Class Notes Stress A condition in which a demand exceeds a person’s coping abilities, resulting in disturbances of cognition, emotion and behavior Psychological stress is a cause or precipitating factor in many diseases, including mental illness (see Table 11-1 on page 328) Psychological stress may exacerbate symptoms and outcomes of many diseases Severe emotional stress has been linked to poor cardiac disease outcomes Stressful events can cause insomnia, appetite changes and physical illness Chronic stress accelerates the aging process in the brain, causing a reduction in synaptic function and brain atrophy (especially in the hippocampus, leading to memory loss) Chronic stress at a young age can cause lifelong alterations in a person’s physiological, psychological and behavioral response to stress Animal research shows that brain changes due to chronic stress are irreversible Stressors Fear, anxiety, anger Major life events (loss of family member, loss of job, divorce) Trauma, abuse, violence Daily hassles, school/work Relationships, caregiving Disease, illness (physical or mental), infection, pain, surgery Lack of sleep, insomnia Malnutrition Prolonged exertion Noise Extreme temperatures Medications, alcohol, other drugs 1  NURS 7053 - Advanced Pathophysiology I for DNP Students Stress and Disease - Class Notes Categories of Stressors A person’s perception of stress is the critical factor Acute stressors Chronic stressors Microstressors Concept of Allostatic Load Wear and tear on the body due to chronic or repeated stress Caused by: Exposure to multiple novel stressors over time (acute, chronic or microstressors) Failure to habituate to repeated stressors Delayed shutdown of the stress response Inadequate stress response that leads to compensation from other mediators Results in constant exposure of cells and tissues to stress hormones that can alter immune function, accelerate disease processes and alter brain structure and function. 2  NURS 7053 - Advanced Pathophysiology I for DNP Students Stress and Disease - Class Notes Stress Response Categories of Stress Responses Reactive: The physiological response from stressors Anticipatory: The physical responses that occur in anticipation of a stressor Conditional: A learned response to specific stimuli (danger) and the anticipatory physiological response it produces Post traumatic stress disorder: Develops after an event that caused harm or the threat of harm; stress response occurs due to flashback memories Central Stress Response Perceived in brain regions that receive sensory information - cerebral cortex Information relayed to the limbic system (amygdala, hippocampus, and hypothalamus) Amygdala Registers fear (also involved in other emotional reactions, memory and decision making) Neurons in the amygdala send projections to the hippocampus and hypothalamus Hippocampus Involved primarily in memory, located near amygdala Prior memories can greatly influence the stress response Hippocampal neurons are particularly sensitive to the effects of cortisol, which promotes memories associated with the stressor 3  NURS 7053 - Advanced Pathophysiology I for DNP Students Stress and Disease - Class Notes Hypothalamic-Pituitary Axis Receives information from amygdala and hippocampus, registers stress and pain Stimulation of hypothalamus results in release of corticotropin-releasing hormone (CRH), adrenocorticotropic hormone (ACTH), and then cortisol Stressor and CRH also activate the sympathetic nervous system causing the release of norepinephrine and epinephrine Stimulation of the hypothalamus results in the secretion of TSH and then T3/T4 Stimulation of neurons in paraventricular nucleus of the hypothalamus results in the release of ADH and oxytocin from the posterior pituitary ADH causes fluid retention Oxytocin promotes psychosocial bonding and attachment Brainstem Limbic neurons also stimulate different regions of the brainstem Example: Locus ceruleus neurons (of the pons) release norepinephrine, which enhances brain activity and contributes to the generalized sympathetic effect of stress 4  NURS 7053 - Advanced Pathophysiology I for DNP Students Stress and Disease - Class Notes Negative Effects of Increased Cortisol Elevation of blood glucose levels (gluconeogenesis and decreased insulin production) Associated disease states: Inhibition of the immune and inflammatory responses (cytokines, WBC function, antibodies) Associated disease states: Note: Chronic exposure to cortisol can lead to loss of tolerance, which has been associated with the development of autoimmune diseases and an inability to suppress inflammatory conditions Reduction in wound healing Development of truncal obesity (lipogenesis) and weight gain Associated disease states: Inhibition of LH, estradiol and testosterone production Associated disease states: Increased sympathetic nervous system activity (see catecholamines below) Reduction in serotonin levels in the brain Associated disease states: 5  NURS 7053 - Advanced Pathophysiology I for DNP Students Stress and Disease - Class Notes Promotion of gastric secretion of acid and enzymes Associated disease states: Enhanced renal excretion of calcium Associated disease states: Interferes with the sleep cycle Associated disease states: Negative Effects of Increased Catecholamines Elevated heart rate and strength of myocardial contraction, myocardial remodeling (hypertrophy, fibrosis, apoptosis) Associated disease states: Peripheral artery vasoconstriction Associated disease states: Peripheral arteriole vasoconstriction leading to reduced blood flow to tissues Associated disease states: 6  NURS 7053 - Advanced Pathophysiology I for DNP Students Stress and Disease - Class Notes Elevation in blood glucose levels (see cortisol above) Increased lipolysis leading to an increase in free fatty acid and cholesterol levels in the blood Associated disease states: Inhibition of general smooth muscle contraction in the GI tract and increases GI sphincter tone Associated disease states: Inhibition of immune and inflammatory responses (especially macrophage and B, T and NK cell populations) (see cortisol above) 7