Impact of HPA-Axis Dysfunction on the Thyroid, Mood and Health - YouTube
Feb 10, 2021 1.01.34h
Biopsychosocial Aspects of HPA-Axis Dysfunction Objectives
- Define and explain the HPA-Axis
- Identify the impact of trauma on the HPA Axis
- Identify the impact of chronic stress/cumulative trauma on the HPA-Axis
- Identify symptoms of HPA-Axis dysfunction
- Identify interventions useful for this population Based on
- Post-traumatic stress disorder: the neurobiological impact of psychological trauma Dialogues Clin Neurosci. 2011 Sep; 13(3): 263–278. https://www.ncbi.nlm.nih.gov/pmc/arti...
- Lifestyle Factors Contributing to HPA-Axis Activation and Chronic Illness in Americans Archives of Neurology and Neuroscience. 2019 Oct.; 5(2) ANN.MS.ID.000608. DOI:10.33552/ANN.2019.05.000608 https://irispublishers.com/ann/pdf/AN...
What is the HPA Axis
- Hypothalamic-Pituitary-Adrenal Axis
- Controls reactions to stress and regulates digestion, the immune system, mood and emotions, sexuality, and energy storage and expenditure
- The signs and symptoms of HPA-Axis dysfunction reflect a persistent, abnormal adaptation of neurobiological systems to trauma or chronic stress.
- In addition to trauma, multiple lifestyle factors have been associated with HPA-Axis dysregulation including
- Noise - Stimulant use (caffeine, nicotine, ADHD medications)
- Insufficient quality sleep
- Media exposure Consequences of HPA-Axis Dysfunction
- More than 50% of Americans suffer from one or more chronic conditions associated with disturbances of the HPA-Axis with an estimated cost of $3.3 trillion annually including:
- Major depressive disorder (20%)
- Generalized anxiety disorder (18.1%)
- Sex hormone imbalances (25%)
- Diabetes (9.2%)
- Autoimmune disorders (23%)
- Chronic pain - Metabolic syndrome (30%)
- Cardiovascular disease (44%)
- Hypothyroid (4.6%)
- IBS symptoms such as constipation and diarrhea
- Reduced tolerance to physical and mental stresses (including pain) Overview of Healthy HPA-Axis Function
- When exposed to a physical, environmental or social stressor, the HPA-Axis is activated and prompts the “fight or flight” reaction.
- Glutamate and Norepinephrine are released
- The hypothalamus releases corticotropin releasing factor (CRF) and arginine vasopressin (AVP) to stimulate the anterior pituitary to produce and secrete adrenocorticotropic hormone (ACTH).
- ACTH causes glucocorticoid (cortisol) synthesis and release from the adrenal glands Overview of Healthy HPA-Axis Function
- Cortisol’s primary function is to
- Increase blood glucose and modify fat and protein metabolism to fuel the fight or flight reaction
- Modulate immune and brain function to effectively manage stressors.
- Cortisol initially causes a potent anti-inflammatory response which allows the organism to react to the stressor without being pain or fatigue.
- Glucocorticoids interfere with the retrieval of traumatic memories
- As cues of the threat wane, the body increases inflammation by releasing proinflammatory cytokines to accelerate wound healing Stress Response
- The response of an individual to stress depends not only on stressor characteristics, but also on factors specific to the individual.
- Perception of stressor
- Proximity to safe zones
- Similarity to victim
- Degree of helplessness
- Prior traumatic experiences
- Amount of stress in the preceding months
- Current mental health or addiction issues
- Availability of social support
- Compared to positive events, negative events, or “stress” causes greater awareness and recall of event details leading to stronger encoding of negative or stressful events.