Unit 5: Obesity Objectives

• occurs when there is an increased energy storage resulting from an imbalance between energy intake and energy expenditure overtime.

• genetics (contributes to 40-70% of the variance in BMI)

• environmental factors (access to food, sedentary lifestyle, high fat foods)

• medical conditions (Cushing syndrome, growth hormone deficiency, insulinoma, psychiatric disorders - depression, binge eating, schizophrenia, genetic syndromes)

• medications (anticonvulsants, antidepressants, antipsychotics, hormones)

Describe the etiology (causes) of obesity.

• involves numerous factors that regulate appetite and energy balance; disturbance of these homeostatic functions results in an imbalance between energy intake and energy expenditure

• appetite

  • the dysregulation of neural network involving hypothalamus, limbic system, brainstem, hippocampus, elements of the cortex and pituitary gland - controls appetite, reward, and energy balance

  • normal communication between these neural networks breaks down to increased reward-seeking behavior for palatable foods and weakened inhibitory control over eating

  • many neurotransmitters and neuropeptides have been identified that can stimulate or inhibit brain’s appetite network and thereby affect total caloric intake

Describe the pathophysiology (what goes wrong in our body) of obesity.

• HTN

• T2DM

• CVD

• NAFLD or MAFLD/NASH

• OA (osteoarthritis)

• Cancer

• Depression

Identify comorbid disease states that are commonly associated with obesity.   

• HTN

• dyslipidemia

• CHD

• Type 2 DM

• sleep apnea

• increased WC (waist circumference)

Identify risk factors that are associated with obesity in the US. 

• the number of calories your body burns while at rest includes digesting a meal and waking up

• includes BMR

Define resting energy expenditure.   

• the minimum amount of energy required by the body to maintain essential functions as rest, such as breathing, circulation, and cell growth.

• portion of RMR

Define basal metabolic rate.  

• REE:

  The minimum amount of energy required to maintain bodily functions at rest, including breathing, circulation, and cell growth. 

• BMR:

  A more specific measurement of REE that is calculated under strict conditions, such as after 12 hours of fasting and 8 hours of sleep

Describe the relationship between resting energy expenditure and basal metabolic rate.

• Neurotransmitters

  • Dopamine - brain (wanting food)

  • Serotonin - GI tract (anorexigenic (appetite-suppressing) effects, modulating satiety and limiting food intake)

  • GABA - the main inhibitory neurotransmitter in the CNS and is heavily involved in feeding behavior

  • Opioids: increase the consumption of highly palatable foods and are involved in the rewarding properties of eating. They are released after palatable food intake and act on opioid receptors in the striatum

• Peptide Hormones

  • Gherlin: Often called the "hunger hormone," ghrelin is the only known circulating gut peptide that stimulates appetite. 

    • produced primarily in the stomach

    • its levels increase before meals, stimulating the brain's hunger centers.

  • Leptin: Secreted by adipose (fat) tissue, leptin is a long-term signal of energy sufficiency. 

    • It suppresses appetite by acting on the hypothalamus to decrease the release of hunger-promoting peptides

  • CCK: short-term satiety peptide released by the small intestine in response to meal intake, especially fat and protein. 

    • It slows gastric emptying, signals satiety, and decreases meal size. Its effects are mediated via the vagus nerve and its receptors in the brain.

  • GLP-1 RA: anorexigenic (appetite-suppressing) peptide released from the intestine in response to food. 

    • promotes satiety, slows gastric emptying, and enhances glucose-stimulated insulin release. GLP-1 receptor agonists are used as treatments for type 2 diabetes and obesity.

• Receptors

  • Hypothalamic receptors: The arcuate nucleus of the hypothalamus is a crucial site for integrating signals related to hunger and satiety, with many key receptors located here, such as LEPR and GHSR.

  • Reward system receptors: Dopamine and opioid receptors in the mesolimbic system are involved in the rewarding aspect of food intake.

  • Gut-brain axis receptors: Receptors on the vagus nerve, such as for CCK and GLP-1, relay signals from the gastrointestinal tract to the brain.

  • Nutrient-sensing receptors: Taste receptors in the gut and on the tongue can also influence peptide release and food intake. 

State neurotransmitters, peptides and receptors associated with food intake.

• BMI (body mass index) is a clinical measure of excess body fat that provides an assessment of total body fat better than weight alone

  • is the practical method of defining obesity

• independent predictor of obesity related disease risk

• most commonly used index of overweight and obesity

Describe the diagnosis of obesity. 

• BMI = body weight (kg) divided by the height of (in meters squared)

Calculate BMI

1.     Calculate ideal body weight and adjusted body weight. (1c)  

• Men less than or equal to 40 inches waist circumference - increased risk of obesity

• Women 35 inches waist circumference - increased risk of obesity

• Men greater than 40 inches is considered abdominal obesity - high risk

• Women greater than 35 inches is considered abdominal obesity - high risk

Interpret waist circumference.

• pulmonary disease (sleep apnea, abnormal function, hypoventilation)

• liver disease (steatosis, steatohepatitis, cirrhosis)

• gall bladder disease

• osteoarthritis

• cataracts

• stroke, heart disease

• cancer (breast, colon, kidney, prostate, uterus, esophagus, cervix, pancreas)

• diabetes, pancreatitis, gout

• death (1 in 5 deaths linked to being overweight or obese)

Describe common complications of obesity.

• Lifestyle modifications

  • 5% - 10% reduction in initial body weight over 3-6 months is a common goal

• weight loss medications

  • orlistat (Alli, Xenical) - leads to about 10% body weight loss after 1 year

  • Phentermine-Topiramate (Qsymia) - approximately >10% of their body weight after 1 year

  • GLP-1 RA

    • Semaglutide (Wegovy) - 15%

    • Tirzepatide (Zepbound) - up to a 15.7% weight reduction

• bariatric surgery - patients maintain an average loss of 50% or more of their excess body weight

Identify three general treatment modalities for obesity and the general weight loss anticipated with each treatment option.   

Set appropriate goals of therapy in treating an obese patient. 

Given a patient with obesity in a case, determine the best general treatment modality. 

• nonpharmacological therapy - (recommended as first line therapy)

  • reduced caloric intake

  • increased physical activity

  • behavioral modification

Describe the lifestyle modifications for obesity.  

• glucagon-like peptide-1 (GLP-1) receptor agonists

  • semaglutide (Wegovy), liraglutide (Saxenda)

• glucose-dependent insulinotropic polypeptide (GIP)/glucagon-like peptide (GLP-1) receptor agonist

  • tirzepatide (Zepbound)

• opioid antagonist/dopamine and norepinephrine reuptake inhibitor

  • naltrexone/bupropion ER (Contrave)

• lipase inhibitor

  • orlistat (Alli - OTC; Xenical - RX)

• sympathomimetic

  • phentermine (Adipex-P; Lomaira)

• sympathomimetic/antiepileptic 

  • phentermine/topiramate ER (Qsymia)

Name the drug classes utilized in the treatment of obesity.

Describe the relationship between the mechanism of action of all obesity drug classes and the pathophysiology of the disease.

Identify common adverse drug effects of each of the obesity class of medications.

Determine how the mechanism of action for the drug classes utilized in obesity contributes to the efficacy and safety of the classes.

Identify monitoring parameters for the drug classes utilized in obesity management based on their mechanism of action.

Using the obesity-focused history, determine appropriate questions for interviewing a patient with obesity to gather subjective information.

Given a role play scenario, gather a detailed eating history in a patient who is overweight/obese.

• men less than or equal to 40 inches - increased risk

• women 35 inches - increased risk

• men greater than 40 inches - high risk

• women greater than 35 inches - high risk

Define what is considered high risk for the waist circumference

Define the waist-to-hip ratio that is considered at-risk

• reduced caloric intake

• increased physical activity

• behavioral modification

Describe the lifestyle modifications for obesity 

Discuss recommended goals for weight loss to aid in improvement in overall health and comorbid conditions

Review dietary recommendations that aid in weight reduction

• men: 1500-1800 per day

• women: 1200-1500 per day

Distinguish between daily caloric recommendations for men and women

• decrease calories by 500-750 calories / day (30%)

Identify the daily caloric deficit that should be targeted to aid in weight reduction

• 8% after 6 months

identify the appropriate rate of weight loss

• to help augment or maintain weight loss you need 200-300 min/wk of moderate intensity physical activity plus muscle strengthening at least 2 days/wk

  • minimize weight gain after a year

• to stay healthy you need 150 min/wk of moderate intensity physical activity plus muscle strengthening at least 2 days/wk

  • with 10 minute intervals for heart health

• Goal is 30 minutes/day for most days of the week

Discuss recommended physical activity goals for weight reduction and cardiovascular health

1. Increase aerobic activity

   1. Goal is greater than or equal to 150 min/week of moderate intensity or 75 min/wk of vigorous intensity

   2. Need to do in at least 10 min intervals for heart health

   3. PLUS muscle strengthening activities at least 2 days/week

2. Increase activity to 200-300 min/week

   1. Help augment or maintain weight loss

   2. Minimize weight regain (> 1 year)

   3. PLUS muscle strengthening activities at least 2 days/week

3. Goal: 30 minutes/day, most days of the week

Describe the weekly recommended amount of physical activity

• Moderate intensity and vigorous intensity

• Moderate intensity

  • aerobic activity at least 150 minutes a week and at least 2 days/week of muscle strength training

• vigorous intensity

Describe the intensity of physical activity that is recommended

• BMI = weight (kg)/height (m squared) or [weight (lbs)/height (inches squared)] x 703

• BMI less than 18.5 - underweight

• BMI 18.5 - 24.9 - normal

• BMI 25 - 29.9 - overweight

• BMI 30 - 34.9 - Class I Obesity

• BMI 35 - 39.9 - Class II Obesity

• BMI greater than or equal to 40 - Class III Obesity

calculate and interpret a BMI

Identify when a patient is adherent or non-adherent to therapy using subjective and/or objective information

1.     Describe how evidence-based techniques lead to a determination of patient understanding (52, 142)  

• Physical consequences

  • cardiovascular disease

  • Type 2 diabetes

  • Musculoskeletal disorders

  • Respiratory problems

  • Kidney/Gallbladder disease

• Mental consequences

  • depression/anxiety

  • cognitive decline

• Other

  • increased healthcare cost

  • reduced life expectancy

Given a patient scenario with an increased weight, elevated BMI, and high waist circumference, counsel a patient regarding two consequences of obesity. (

• reducing caloric intake

• increasing physical activity

• managing behavioral situations (managing stress/depression & improve sleep)

Given a patient with obesity, counsel a patient regarding three lifestyle modifications they should utilize to help with weight management

• healthy weight loss is 5-10% over 6 months

  • 1-2 pounds per week

1.     Given a patient with obesity, counsel a patient regarding what healthy weight loss is. (98)  

• checks for understanding by asking person to repeat back key information (dosing regimen, adverse effects, what to do about missed doses)

1.     Demonstrate teach-back method for assessing patient understanding. (142)  

• first person strengths: nonjudgmental, unbiased, caring, free from stigma; places an emphasis on the person as an individual instead of the disease

  • she has diabetes, she has obesity

• strengths based language: improves communication and motivation; fosters hope and collaboration

  • increased BMI (fat), weight management (excess fat), unhealthy weight (large size), carrying higher weight (obese), eating habits (diet), physical activity (exercise)

Given examples of communication with a person carrying extra weight, identify examples of words and language that either violate or are consistent with person-first or strengths-based language.

the extent to which a person’s behavior - taking medications, following a diet, and/or executing lifestyle changes - corresponds with agreed recommendations from a healthcare provider

1.     Define adherence. (40, 41)  

• primary non-adherence

  • not filling a new RX

  • 30% of newly prescribed medications are never picked up at the pharmacy

• partial non-adherence

  • missing 20% or less of prescribed doses

• repeat non-adherence

  • consistently missing >20% of prescribed doses

• persistence

  • duration of time from start of therapy until discontinuation

1.     Differentiate between types of nonadherence. (40, 41)  

• compliance: following instructions (making a recipe one time); patients are passive or obedient participants in the decision to take medications

• adherence: active and engaged decision to follow plan (making recipe over and over again)

  • 80% is considered “adherence” in many research studies; 95% is critical for HIV

1.     Differentiate between the terms adherence and compliance. (40, 41)  

• subjective vs objective measures

  • subjective: self reported (patient diaries), structured questionnaires, patient interview

  • objective: pill counts, refill records, insurance claims, electronic monitoring devices

• direct vs indirect measures

  • direct measures: blood serum levels, ingestible sensors, observation

1.     Differentiate objective and self-reported measures of adherence. (40)  

• look at glucose monitoring records

• proportion of days covered (PDC) from claims

• assess patient self reporting

1.     Given a patient with diabetes mellitus, identify at least one method to measure adherence. (40, 19)  

• questionnaires/patient diaries

• pill counts, electronic monitoring, tracking behavioral goals

1.     Given a patient with obesity, identify at least one method to measure adherence. (19, 40)  

• health system/HCT factors: long wait times, lack of time with patients, lack of community support, patient-provider relationship 

• condition related factors: severity of symptoms, level of disability, comorbidities

• patient related factors: forgetfulness, lack of understanding, low literacy

• social/economic factors: poverty, low level of education, lack of transportation

• therapy-related factors: complexity of regimen, duration of treatment, adverse effects

1.     In a patient scenario with diabetes, evaluate barriers to adherence. (40, 41)  

1.     In a patient scenario with obesity, evaluate barriers to adherence. (40, 41)  

• educational: provide clear information, tailor to patient’s situation

• behavioral: pill boxes, calendars, email reminders

• administrative support: tailoring of medications regimens, recommend change in therapy if adverse effects are a problem, automated refills, 90 say supplies, medication reconciliation 

List interventions available to improve adherence with treatments for diabetes and obesity.

• leads to poor blood sugar control

• increased risks of complications

• higher hospitalization rates

• early mortality

Explain why non-adherence is a medication-related problem for a patient with type 1 or 2 diabetes mellitus.

• worsening health outcomes

• exacerbate the chronic nature of obesity

• higher health care costs/hospitalizations

1.     Explain why non-adherence is a medication-related problem for a patient with obesity. (25)

• leptin and insulin resistance: Hormones like leptin (from fat cells) and insulin (from the pancreas) signal to the hypothalamus to suppress appetite.

  • In obesity, a state of resistance develops, meaning the brain does not properly receive or respond to these satiety signals, leading to persistent feelings of hunger.

• gherlin dysregulation: the "hunger hormone" ghrelin, secreted by the stomach, is elevated before meals.

  • In obesity, its signaling to the mesolimbic reward system may be altered, further stimulating appetite.

What hormones regulate homeostasis for monitoring the body’s energy status and controlling basic sensations of hunger and fullness (satiety)?

• brain region composed of several distinct nuclei, involved in coordinating the GI and nervous systems to the endocrine system,

• major structure controlling appetite

hypothalamus

• causing appetite suppression

anorexigenic

• causing increased appetite

orexigenic

pertaining to the cessation of hunger

satiation

the sensation of being full

satiety

• specialized endocrine cells of the GI tract and pancreas

enteroendocrine cells

• any gut hormone (GLP-1 and GIP) released in response to eating and stimulate the pancreas to release insulin which helps lower blood sugar levels

• regulate appetite

• slow digestion

• reduced the amount of sugar released by the liver

• aid in weight loss and provide cardiovascular protection

Incretin

• several hormones released from the gut in response to food intake exert anorexigenic (appetite-suppressing) responses in the brain, particularly in the hypothalamus

What are anorexigenic hormones?

• Glucagon-like peptide-1 receptor agonist (GLP-1 RA) - slows stomach emptying and increasing feelings of fullness to lower blood sugar and reduce appetite

• cholecystokinin (CCK) - stimulates contraction of gallbladder to release bile, triggers pancreas to secrete digestive enzymes, promotes satiety, and regulates appetite

• peptide tyrosine tyrosine (PYY) - appetite regulating hormone produced in the gut which is released after feeding to reduce hunger and promote satiety

• pancreatic polypeptide (PP)

• oxyntomodulin (OXM or OXY)

• Leptin- hormone produced by fat cells that signals the brain that there are sufficient fat stores, suppressing appetite and promoting satiety

• Insulin - suppresses appetite by crossing the blood-brain barrier to stimulate hypothalamus (inhibit neurons that promote hunger and activate neurons that promote satiety)

Name some anorexigenic hormones.

• a hormone made by fat cells that decreases your appetite

• lower when you are thin and higher when you’re obese

• in obesity, people develop a resistance to the appetite- suppressing effects of leptin

What is leptin?

• a hormone that increases appetite and also plays a role in body weight

• from the stomach

• “hunger hormone”

What is ghrelin?

• Underweight: BMI of less than 18.5

• Normal range: BMI of 18.5 - 24.9

• Overweight: BMI of 25 - 29.9

• Obesity: BMI of more than 30

  • Class I Obesity: 30 - 34.9

  • Class II Obesity: 35 - 39.9

• Extreme obesity: BMI over 40 (Class III)

Interpret body mass index (BMI) - what do the values mean?

• Ghrelin (reduce satiety)

• Leptin

• GLP-1

• Insulin

Which of the following hormones induces satiety?

• Gastrin (stimulates the secretion of HCl in the stomach to aid in digestion in preparation for food) - makes you feel hungry

Which hormone has an impact on the hypothalamus and controls satiety and is secreted from the stomach?

• enhances satiety in the brain

• reduces GI motility

• makes me feel full

How do GLP-1 agonist make you lose weight?

Classification of BMI chart

Calculate BMI (round to nearest tenth decimal place)

39.37 inches

How many inches in one meter?

BMI and Waist Circumference Chart

Health Risk Classification based on waist-to-hip ratio

5-10%

What is the goal weight loss for all therapies?

Which medications increase energy expenditure?

Which medication decreases food absorption?

Which medications decrease appetite?

• men: 1500-1800 per day

• women: 1200-1500 per day

What is the calorie goal for men and women?