Lecture 23 Obesity part 1 Flashcards
What are negative aspects/effects of obesity?
Metabolic: T2D, HTN, dyslipidemia, gout, FLD, infertility, cancer
Mental: depression, anxiety, low-self esteem, disordered eating/eating disorders, body dissatisfaction
Mechanical: obstructive sleep apnea, GERD, OA, plantar fasciitis, urinary/fecal incontinence, intertrigo
Monetary: education, employment, professional development, increased cost of living, cost of weight-loss programs
How is the hypothalamus involved in appetite control?
hormonal + neural signals from gut, adipose, and peripheral organs ⇒ arcuate nucleus - Agouti-related protein (AgRP), neuropeptide Y (NPY) ⇒ hunger sensation + food seeking behaviour ⇒ EATING ⇒ proopiomelanocortin (POMC), cocaine and amphetamine related transcript (CART) release ⇒ inhibitory receptors Y1, GABA ⇒ suppression of food intake
How is the mesolimbic (hedonic area) involved in obesity/food intake?
involves neural systems providing emotional, pleasurable and rewarding aspects of eating
signals transmitted by dopaminergic, opioid and endocannabinoid pathways
Dopamine - release in brain signaling desire to eat in response to emotional triggers
Opioid/Endocannabinoid - responsible for feeling of pleasure associated with eating
How is the cognitive lobe (executive functioning) involved in obesity/food intake?
overrides the primal behaviours driven by mesolimbic system and fxn best under optimal conditions
excessive eating often occurs under suboptimal conditions,, possible dysfunctional connection between cognitive lobe and rest of brain that leads to inability to control eating behaviours
significant crosstalk between homeostatic and hedonic eating which is mediated by endocrine and gut signals - Leptin, insulin, ghrelin, GLP-1
Leptin (where does it come from, function)
secreted from adipose
Function: signals hypothalamus to decrease appetite and increase energy expenditure
in Obesity: leptin resistance - fail to suppress hunger
Ghrelin (where does it come from, function)
secreted from stomach
Function: stimulates appetite
in Obesity: dysregulated, contributes to increased hunger
Peptide YY and GLP-1 (where do they come from, function)
gut-derived hormones
Function: promote satiety and slow gastric emptying
in Obesity: activity is blunted, reduce feeling of fullness
What are the classifications of weight using BMI?
all are in kg/m^2, with first number being for caucasians and second form asian/south-asian, Underweight: <18.5, <18.5
Normal: 18.5-24.9, 18.5-22.9,, Overweight: 25-29.9, 23-26.9
Obesity: 30-39.9 (Class I 30-34.9, Class II 35-39.9), >/=27
Severe Obesity: >/= 40
What is the Edmonton Obesity Staging System?
Stage 0: no apparent risk fx, physical sx, mental health issues or fxn limits
Stage 1: pre-clinical risk fx (borderline HTN, mild sx or impairment) no sig impact on life
Stage 2: established these related chronic diseases (HTN, DM, OA), moderate mental health concerns or moderate fxn limits
Stage 3: end-organ damage (HF, severe OA), sig mental challenges, sig fxn limits affecting life
Stage 4: end-stage severe, potentially life-threatening conditions (end-stage organ damage, severe disability, need for intensive care)
What is considered preclinical obesity?
a physical phenotype characterized by excess adiposity and absence of S&S of organ dysfxn due to obesity
state of excess adiposity with preserved fxn of other tissues and organs and a varying but generally increased risk of developing clinical obesity and several other diseases
What is considered clinical obesity?
a chronic systemic illness characterized by alterations in fxn of tissues, organs, entire person or combo due to adiposity
requires fulfillment of 2 main criteria ⇒ Anthropometric Criteria: in addition to BMI at least one of waist circumference or direct measure of body fat
Clinical Criteria: one or both of following ⇒ S&S of ongoing organ dysfxn, age-adjusted limitations of mobility or other activities of daily living
What are the 5As of Obesity care?
ASK: permission to discuss weight and explore readiness, non-judgemental, motivational interviewing
ASSESS: obesity related risks and root causes of obesity, obesity class and stage, obesity drivers, complications, barriers
ADVISE: health risks and tx options, explain benefits of modest weight loss, need for long-term strategy
AGREE: health outcomes, behavioural goals, realistic and sustainable, begin with addressing drivers of weight gain
ASSIST: accessing appropriate resources and providers, identifying drivers and barriers, provide education, arrange follow-up
