Anthropology 243 Medical Anthropology: Human Biology and Health Fall 2024 PDF

ANTHROPOLOGY 243 MEDICAL ANTHROPOLOGY: HUMAN BIOLOGY AND HEALTH FALL 2024 ANNOUNCEMENTS Homework 5 and 6 now posted on Brightspace HW 5 due by 11:59pm on Thursday, December 5th HW 6 due by 11:59pm on Tuesday, December 10th Meg Gauck’s guest lecture Post...

ANTHROPOLOGY 243 MEDICAL ANTHROPOLOGY: HUMAN BIOLOGY AND HEALTH FALL 2024 ANNOUNCEMENTS Homework 5 and 6 now posted on Brightspace HW 5 due by 11:59pm on Thursday, December 5th HW 6 due by 11:59pm on Tuesday, December 10th Meg Gauck’s guest lecture Posted, content for exam is slides with check marks Review Sheet, Exam 3 Part 1 now posted Part 2 (last lecture info) will be posted on Thursday WHAT DOES STRESS MEAN TO YOU? OUTLINE (WILEY & ALLEN CHAPTER 10) Stress in humans vs. other animals Biological stress response Autonomic stress system Hormonal stress system Allostatic Load Health outcomes of chronic activation of biological stress systems Cardiovascular disease Impaired immune function Social Inequality, stress and health SES gradient Whitehall Studies Protective factors against stress-related disease Social cohesion Social support Race, stress and health Scientific racism Flawed biological assumptions about race Racial disparities in health HUMAN STRESS IS UNIQUE Stressors in animals Stressors in humans Threats to survival or Threats to survival (rarer) reproduction and social situations (common) predators, competitors, Timing temperature extremes, Immediate, anticipated, food shortages and recalled threats Timing Personal Importance of *perception* Immediate Frequency Frequency Chronic Episodic noteronic CONTEMPORARY STRESS PROFILES: ANCESTRAL OR NEW? Did our hunter-gatherer ancestors live with as much stress as we do now? Mismatches between and ancestral and contemporary environments Kin-based social groups vs. social stratification STRESSORS AND INTERNAL BALANCE Stressor anything that disrupts physiological balance and activates stress response Homeostasis “same” “steady”; the tendency of the body to maintain a constant internal environment in response to environmental changes Allostasis “maintaining stability through change”; the physiological processes that allow organisms to adapt to stressors Long term disruption of homeostasis by stressors ➜ allostatic load and negative health consequences BIOLOGY OF THE STRESS RESPONSE: PHYSIOLOGICAL AND ENDOCRINOLOGICAL REACTIONS THAT ALLOW ORGANISMS TO ADAPTIVELY RESPOND TO STRESSORS The Autonomic Nervous System Hormonal Stress Response Immediate stress response Delayed stress response Mobilizes energy Replenishes energy resources to muscle cells stores through Increases heart rate, bp, synthesis of glycogen respiration and mental (stored glucose) and acuity fat deposition Sympathetic system Hypothalamic-pituitary- adrenal (HPA) axis ”Fight-or-flight” Parasympathetic system “Rest-and-digest” FIGHT OR FLIGHT: THE STRESS RESPONSE IS ADAPTIVE IN AN EMERGENCY Energy needed No energy wasted on unnecessary functions Storage inhibited These functions are inhibited Stored energy mobilized Digestion (blood flow to digestive tract decreased) Muscles need oxygen Reproductive physiology and Breathing rate increases behavior Heart rate rises Growth, tissue repair Vasoconstriction ➜ BP Pain perception suppressed increases Changes in immune function Water retained to increase blood volume  AUTONOMIC NERVOUS SYSTEM Parasympathetic nervous system: ”Rest-and-digest" or "feed and breed” Sympathetic nervous system: ”Fight-or- flight” Norepinephrine (noradrenaline) Epinephrine (adrenaline) Wiley & Allen Fig. 10.2  HORMONAL STRESS RESPONSE delayed Hypothalamic-pituitary-adrenal axis (HPA axis) Corticotrophin-releasing hormone (CRH) Adrenocorticotropic hormone (ACTH) Cortisol Increases glucose availability in bloodstream and for the brain Increases bp and cardiac output Suppresses nonessential activities (digestion, reproduction) Chronic elevated cortisol can suppress immune response and lead to type 2 diabetes and CVD  Allostasis – maintaining stability through change STRESS RESPONSE AND ALLOSTATIC LOAD (McEwen 1998) STRESS-RELATED ILLNESS Stress response not designed for long-term or frequent activation Chronic stress can lead to Damage to cardiovascular system Immunosuppression STRESS HORMONES AND CARDIOVASCULAR DISEASE Chronic release of epinephrine → ↑ blood pressure → heart works harder and increases force on blood vessels → heart responds by building muscle around the left ventricle → heart attacks → tears in blood vessels → inflammation → plaques → heart attacks and stroke Chronic release of cortisol → ↑ negative metabolic effects ↑insulin released to take up excess circulating glucose → deposition of glucose in visceral (abdominal) fat cells ↑ Risk for CVD and Type 2 diabetes ↑insulin resistance Risk for Type 2 diabetes STRESS AND HEALTH: IMMUNE FUNCTION (Cohen et al. 1991 and 2002) SO HOW DOES SES “GET UNDER THE SKIN”? WHEN ARE STRESS RESPONSES ACTIVATED? Stress responses more likely to be activated when individuals: feel as if they have minimal control over stressors feel as if they have no predictive information about the duration and intensity of the stressor have few outlets for the frustration caused by the stressor interpret the stressor as evidence of circumstances worsening lack social support for the duress caused by the stressors (Sapolsky 2005) SES AND HEALTH Socioeconomic status (SES) A composite measure that includes income, occupation, education, and housing conditions “SES gradient” – every step downward in SES correlates with poorer health Risk of some diseases increase 10-fold from lowest to highest SES category 5-10 year mortality difference between lowest and highest SES categories INCOME INEQUALITY AROUND THE WORLD GDP AND AVERAGE LIFE EXPECTANCY (WILEY & ALLEN, FIG. 10.5) WHITEHALL STUDIES Studies of health in British civil service workers Ranked positions are associated with income differences All workers have access to health care (universal healthcare) Results Significant differences in risks of many diseases and mortality between ranks Results have been replicated in other countries with socialized medicine Findings hold even when corrected for negative health behaviors Behavioral risk factors (e.g., smoking, physical inactivity) accounted for less than 1/2 of the difference in mortality between high and low ranks WHITEHALL STUDIES, CONT’D Lower SES increases risk factors and decreases protective factors More smoking, drinking, obesity More likely to live in violent/polluted neighborhood Less access to clean water, healthy foods, health clubs, adequate heating/cooling Surprisingly, explains relatively little about SES health gradient Whitehall study: risk factors (smoking, exercise, etc) accounted for less than 1/2 of the effect WHITEHALL STUDIES: RELATIVE STATUS AND ILL HEALTH WHITEHALL STUDIES: RANK AND CHD MORTALITY Structure of Society is Stressful (competition , unsureness , etc. ) SOCIAL MODERATORS OF THE STRESS RESPONSE Social cohesion/social capital Group well-being Connections and shared values that enable individuals and groups to trust each other and so work together Social support/social integration Directly linked to improve health outcomes: Improved recovery Decreased distress Lower mortality due to illness SOCIAL SUPPORT AND MORBIDITY SOCIAL SUPPORT AND MORTALITY Figure 2.2 Wiley & Allen, “Comparison of odds of decreased mortality across several conditions associated with mortality.” NEXT TIME Continue reading Ch. 10 in Wiley and Allen Stress, Social Inequality, and Race and Ethnicity p. 338 – 354 IDENTIFIABLE HEALTH DISPARITY AMONG RACIAL/ETHNIC GROUPS: LIFE EXPECTANCY IDENTIFIABLE HEALTH DISPARITY AMONG RACIAL/ETHNIC GROUPS: LOW BIRTH WEIGHT (