Themes 4 and 5: Eating disorders and Stress Flashcards
what is anorexia nervosa and how does it present?
lower energy intake than normal leading to significantly low weight. intense fear of weight gain and/or drastic acts to prevent weight gain. has disordered views of body/ weight
presentation:
visual signs- muscle wasting, dry skin, thin hair, brittle nails
systemic signs- hypothermia, bradycardia, arrhythmia, heart failure, renal failure, osteopenia, hypotension, reduced sensation and muscle power
psychological signs- lack of motivation and empathy, irritable, depression, anxiety, obessesionality, compulsions
what is bulimia nervosa and how does it present?
repeated binge eating episodes followed by repeated efforts to compensate for the binge eating to prevent weight gain- self induced vomiting, laxative misuse, fating/ excessive exercise
presentation:
visual signs- lymph node/salivary/ parotid gland enlargement, Russell sign (inscisor marks on hand from making oneself vomit), enamel erosion (lingual surface), bowel disturbance/constipation, sore throat, halitosis (bad breath),
systemic effects- similar to AN
what is OSFED and what are the different types ?
other specified feeding and eating disorder
OSFED typical AN- applies when all other criteria are met for AN except significantly low body weight
OSFED atypical BN or BED- al other criteria met except frequency/ duration
purging disorder- induced vomiting/laxative abuse but no binge eating
night feeding syndrome- recurrently eating large amounts at night after waking from sleep
what is binge eating disorder and how can it present?
repeated binge eating episodes (at least once a week for 3 months)- eats more food than normal in a discrete period of time and feels lack of control over eating. compensatory behaviours are not used.
presentation- gastric rupture, obesity, mood disturbance (every low mood, distressed), substance misuse, self harm
what is pica and rumination disorder?
pica- compulsive ED in which people eat non food items
rumination disorder- people repeatedly and unintentional regurgitate undigested of partially digested food, riches it then either reswallow it or spit it out
what is the definition of stress?
the physiological changes following exposure to diverse physical, chemical or emotional challenges. stress encompasses the input, processing systems and the output/ stress response
what are stressors?
factors that initiate a stress response.
physical stressors- very hot/cold temperatures, injury, chronic illness, pain
pschological stressors- events, individuals, comments, situations or anything we interpret as negative or threatening
what are the stages/types of stress?
stage 1: acute stress- a response to demands of the recent past or anticipated demands and pressures of the near future. when the situation ends stress signals switch off and the body return to normal
stage 2: episodic stress- extended over arousal due to repeated acute stress
stage 3: chronic stress- occurs when an individual fails to see a way out of a situation. arises from unrelenting demands and pressures for long periods of time
what are the behaviours controlled by the hypothalamus?
endocrine function sexual behaviour temperature regulation regulation of body water- thirst GI and feeding regulation- hunger, desire for food circadian rhythms- sleep/wake cycle
what are the major physical manifestations of stress?
tachycardia/ hypertension acute hypoinsulinaemia- hyperglycaemia splenic contraction- increased mobilisation of blood cells decreased clotting time decreased GI activity sweating pupillary dilation
what is the mechanism of action of the acute stress response?
perception of stress
amygdala interprets information
communicates with hypothalamus- stimulates sympathetic NS
SNS exerts effects e.g stimulates adrenal medulla causing release of adrenaline and noradrenaline which target tissues such as the heart, GI system, blood vessels, eyes etc.
what are the physiological effects of catecholamines?
CV effects- increased HR, contractility and vasoconstriction = increased BP
increased glucose levels- stimulates glycogenolysis and gluconeogenesis (liver), inhibition of insulin secretion (pancreas), inhibition of glucose uptake in fat cells
how is the HPA axis triggered in stress?
cortex receives sensory/psychological information and communicates the threat to thy hypothalamus which stimulates the anterior pituitary by releasing corticotrophin releasing hormone. the anterior pituitary secretes adrenocorticotrophic hormone (ACTH). this stimulate the adrenal cortex to release glucocorticoids such as cortisol.
what are the effects of glucocorticoids/ cortisol?
metabolism effects- gluconeogenesis, glycogenolysis, protein degradation in muscle, lipolysis in adipose tissue, matrix protein breakdown in bone, insulin inhibition in pancreas
immunosuppression- prevents production of cytokines, suppress T cell activation, inhibits inflammatory vasodilation, vascular permeability and leukocyte extravasation
what are the health risks of stress?
Atherosclerosis, chronic hypertension
type 2 diabetes, obesity- due to increased insulin resistance
reduced immunity
back pain/headaches- muscle tension
emotional/ behavioural changes, insomnia, anxiety, depression, ED,
