Physiological Response to Stress - Dr Charlotte Illsley (2023-24).pptx

The physiology of stress Year 1 2023-2024 Charlotte Illsley [email protected] PSQ C505 Acknowledgement Dr Helen Watson Intended l...

The physiology of stress Year 1 2023-2024 Charlotte Illsley [email protected] PSQ C505 Acknowledgement Dr Helen Watson Intended learning outcomes By the end of this session, you should be able to: Define stress (physiological) and give examples of stressors Consider the response to stress as being acute or longer term Explore physiological processes which underpin the body’s response to stress and relate this to previous discussion of the cardiovascular, respiratory, endocrine and nervous systems Recall some of the changes that the body undergoes during exercise stress Introduce the possibility that prolonged stress may have some specific effects on the teeth and oral cavity Why learn about stress? As a practitioner – avoid ‘burnout’ Patients may be very stressed about dental procedures Patients may have long term stress and associated illness Need to understand underlying physiology https://www.nature.com/articles/sj.bdj.2 019.46 What do we mean by stress? What does it feel like when you’re stressed? What causes us to be stressed in our lives? What caused early humans to be stressed? Too many emails, moving house, earthquake, arguments, no money, traffic jams, being chased by a lion, queue at the supermarket….. Universal/subjective? http://www.nhs.uk/Conditions/stress-anxiety-depression/Pages/understanding- What do we mean by stress? Physiological stress is the response of an organism to stressors It is counteracted by physiological and behavioural responses Involves the sympathetic (fight or flight) and parasympathetic (returning to normal) nervous systems and several other systems in the body Aside from the physiological response, changes in behaviour with stress may manifest in physical conditions (smoking, tiredness, alcohol etc) Exercise stress describes the changes our body makes to deal with the demands (e.g. more oxygen to skeletal muscles) of physical activity  Acute stress Stress can be acute with responses lasting a short time E.g.: cycling down a hill fast, job interview, looming deadline These individual events can be exciting and are not damaging by themselves Some individuals will have repeated bouts of stress like this Lots of short term stress can be damaging https://www.thoughtco.com/the-funniest-rolle r-coaster-reaction-faces-1924623 Long term (chronic) stress Ongoing issues – can’t see a way out E.g.: poverty, war, abuse, unhappy relationships Ongoing stress has damaging effects May be used to high level of stress and not notice it Increase in risk of heart attack, high BP, suicide, cancer? Suppression of immune system Why have we evolved this way? Immediate survival would have been most important Autonomic nervous system – sympathetic vs parasympathetic recap SYMPATHETIC – ‘fight or PARASYMPATHETIC – rest, flight’ digest, recover, restore Pupils dilate Pupils constrict Vasoconstriction ↑ gut motility and secretion ↓ gut motility and secretion ↑ saliva secretion ↓ saliva secretion ↓ heart rate ↑ heart rate and force http://clipart-library.com/sleeping-cartoons.htm  Physiology of stress When we encounter a stressor our body reacts The initial response is ‘fight or flight’ The sympathetic NS has a key role in the stress response The amygdala in the brain stimulates the hypothalamus The hypothalamus activates the sympathetic nervous system which prepares the body for fight or flight http://rhys-gravell.wixsite.com/physiologyoftrauma/fight-or-flig  Physiology of stress Cortisol stimulates… There are longer lasting aspects of the Gluconeogenesis stress response – sometimes called the resistance reaction Proteolysis (after some time) These responses are hormonal Lipolysis? Corticotropin-releasing hormone Reduced inflammation (CRH) is released from the Suppression of immune hypothalamus system CRH stimulates the pituitary gland to Reduced wound healing and release adrenocorticotropic hormone bone formation (ACTH) ACTH stimulates cortisol release from These effects are helpful in the adrenal cortex (adrenal gland) Cortisol is a steroid hormone and key in the short term but can be the stress response damaging if cortisol is Cortisol levels can be measured in saliva present long term Cortisol Cortisol is required to stay healthy – lack of it can be life threatening If the adrenal glands are impaired or destroyed, synthesis of steroid hormones (including cortisol) is reduced Lack of cortisol (for example in Addison’s disease) can lead to severe symptoms during stress (crisis) including: Low blood pressure Hypoglycaemia Vomiting, diarrhoea and resulting dehydration Can be treated with extra cortisol (hydrocortisone tablets) in the long term and IV glucocorticoids and saline (with glucose) during crisis  Physiology of stress In addition to cortisol (via CRH), there are other hormones released Growth hormone releasing hormone (GHRH) comes from the hypothalamus and causes release of human growth hormone (hGH) from the pituitary gland Thyrotropin-releasing Hormone (TRH) is released from the hypothalamus and stimulates the pituitary to release thyroid stimulating hormone (TSH) http://rhys-gravell.wixsite.com/physiologyoftrauma/resistance-r eaction Physiology of stress – damaging effects If the stressors continue or the body is unable to restore homeostasis, damaging effects can occur including: Emotions – anger, irritability, Tension anxiety/depressi headaches, on migraines Immunosuppression and increased risk of Prolonged infection increased BP and heart rate, associated Increased risk of damage to CV type 2 system diabetes(extra glucose released) Gut problems – heartburn, ulcers, Muscular pains, tension, constipation, increased chance of diarrhoea, IBS injury, muscle wasting Physiology of exercise stress When we exercise, the body has a different stress response with some similar features Increased delivery of oxygen and energy to muscles is needed ATP stores are depleted in muscle so more is made from creatine phosphate +ADP, and by anaerobic and aerobic respiration The body needs to be coordinated and movement is regulated by sensors in the muscle (refer to skeletal muscles session) In the cardiovascular system, the sympathetic nervous system causes increased heart rate and force of contraction Local vasodilation in muscles allows increased oxygen delivery Ventilation increases as increased CO2 levels are detected Cortisol is released in strenuous activity (stress response) Antidiuretic hormone (ADH) and aldosterone are also released to conserve water  Stress and Oral Health Vasiliou A, Shankardass K (2016) Reported an inverse relationship between current stress and oral health and oral pain Effects were modified when confounding factors (age, sex and income) were considered but still persisted  Physiological Stress Oral- systemic relationship Link between overall Unhealt health and oral health hy Behavio Believed to affect oral ur How does health in two ways stress act on the body ? Physiologic al dysfunctio n  Examples of unhealthy coping strategies Alcohol Smoking Poor diet Substance use Sedentary behaviour Self neglect How may these behaviours affect oral health and risk of disease?  Can stress affect underlying mechanisms of disease progression? Effects of chronic stress can include: Increase in pro inflammatory cytokines suppression of immune system Decrease in reduced wound healing and bone lymphocyte proliferations formation chronic inflammation, even in the and population presence of glucocorticoid release Decrease antibody production How may this be seen in the mouth? Cross reference with immune system - LB Other factors associated with stress Co morbidities- obesity, diabetes, CVD These also are risk factors for some oral diseases Medications (for stress or co morbidities) and their side effects Dry mouth, ulceration, gingival hyperplasia Epigenetics: growing evidence external factors can alter gene expression and susceptibility to disease.  Some oral diseases associated with stress Periodontal disease Bruxism Oral Lichen Planus TMJ PDS RAU ANUG Dry mouth (antidepressants)  Periodontal Disease Warren et al. (2009) reviewed the evidence of stress, depression and periodontal disease being related. They concluded that: Periodontal disease is multifactorial and chronic stress can modify many of these factors. Psychological stress influences the progress and onset of chronic disease including periodontitis in susceptible patients Markers of stress consistently related to measures of disease e.g. Increased salivary cortisol levels correlated with increased measures of stress and periodontal disease Stress can enhance the responsiveness and production of inflammatory cytokines by M1 macrophages to an oral pathogen leading to increase in tissue destruction Stress reduces the immune responsiveness to pathogenic infections Model of the effects of chronic psychological stress and depression on periodontal disease. Adapted from Elter et al. Complex relationships and multifactorial disease process  Recurrent Aphthous Ulcers Conflicting data regarding stress- some studies show association with stress- causal? Difficulties : measuring stress, confounding factors McCartan (1996) found patients with RAU had elevated levels of cortisol in their saliva and scored higher in anxiety levels Proposed mechanisms: behaviours- cheek biting/chewing/parafunction poor diet and deficiencies of Iron, B12, folic acid reduced salivary peroxidase levels leading to increased cell damage from increased levels of hydrogen peroxide reduced wound healing  Clinical Implications Take a full medical history, including mental health and medications. Be able to explain to patients why mental health may be of relevance to oral disease. Understand that oral health is part of systemic health and there are complex relationships between these two aspects of health. Consider whether patients with chronic stress or poor mental health may be at higher risk of oral diseases - and use preventive measures as appropriate. Intended learning outcomes By the end of this session, you should be able to: Define stress (physiological) and give examples of stressors consider the response to stress as being acute or longer term explore physiological processes which underpin the body’s response to stress and relate this to previous discussion of the cardiovascular, respiratory, endocrine and nervous systems recall some of the changes that the body undergoes during exercise stress introduce the possibility that prolonged stress may have some specific effects on the teeth and oral cavity Resources https://www.ncbi.nlm.nih.gov/books/NBK278995/ Website from one of our medical students: http://rhys-gravell.wixsite.com/physiologyoftrauma Role of chronic stress and depression in periodontal diseases. Warren K.R et al. Periodontology 2000 Vol.64,2014, 127-138 BMJ article on stress in UK general dental practitioners https://www.nature.com/articles/sj.bdj.2019.46