25 terms

GI Exam 2 Obesity

Etiology of Obesity
Disorder of energy imbalance
Calories/Energy Intake > Physical Activity/Energy Expenditure
1. BMI 25-29.9
2. BMI 30-34.9
3. BMI 35-39.9
4. BMI >40
1. Overweight
2. Obesity Class I
3. Obesity Class II
4. Obesity Class III
Risk Factors for Mortality (3)
1. Overweight/obese BMI > 25
2. Central distribution of fat
2a. Waste circumference (Men > 40in; Women > 35in)
3. Patients with risk factors (e.g. HTN, DM, Hypercholesterolemia, Sleep Apnea, CV Disorders)
Secondary Etiologies to Obesity (3)
1. Hypothyroidism
2. Binge eating/psychological
3. Medications (corticosteroids, antidepressants, antipsychotics, sulfonylureas, insulin, birth control pills, beta-blockers, lithium)
Treatment of Obesity
1. BMI 25-26.9
2. BMI 27.29.9
3. BMI 30-35
4. BMI 35.39.9
5. BMI > 40
1. Diet/Exercise/Behavior Therapy If comorbidities
2. (Diet/Exercise/Behavior Therapy + Drug Therapy) x If comorbidities
3. Diet/Exercise/Behavior Therapy + Drug Therapy
4. Diet/Exercise/Behavior Therapy + Drug Therapy + Surgery if comorbidities
5. Diet/Exercise/Behavior Therapy + Drug Therapy + Surgery
Treatment of Obesity Strategy (4)
1. Set realistic goals
2. Aim to lose 10% of baseline weight over 6 months
3. Use diet, exercise, and behavior modifications that can be sustained
4. After 6 months of keeping off the weight, think about losing more
Method to Achieve Slow Weight Loss
Calories vs. Weight gain/loss
1. 3500kcal ~ 1 pound increase in weight
2. Negative calorie balance of 500-1000 kcal/day is required to lose 1-2 lb/week
2a. (i.e. Subtract 500-1000kcal from the patient's EEE to determine goal caloric intake)
First-Line Therapy
1. Dietary Therapy
2. Physical Activity
3. Behavior Modification
1. Reduce calories but not very low calorie diets
2. Increase exercise with consideration of patient preference, experience, access, and orthopedic limitations
3. Self-monitoring, stimulus control, stress management, cognitive change, contingency/relapse management
Pharmacological Therapy (not until 6 months)
1. Key Points (2)
2. Criteria for use
1a. Always use meds in combination with diet, exercise, and behavior modifications
1b. Always use an agent that is known to be safe and effective for long term-use
2a. BMI > 30
2b. BMI 27-29.9 and 2 risk factors
Orlistat (Xenical and Alli)
1. MOA
2. Dosage
3. Age restrictions
Only currently available agent that is FDA-approved for long-term use
1. MOA: Selective inhibitor of gastrointestinal lipases decreasing formation of free fatty acids and a reducing dietary fat absorption
2a. Rx: 120mg TID before meals (Prn)
2b. OTC: 60mg TID before meals (Prn)
3a. Xenical FDA-approved for patients > 12 years of age
3b. Alli FDA-approved for patients > 18 years of age
1. Side effects (2)
2. Drug interactions (3)
3. Rare adverse effect
1a. 80% experience GI side effects
1b. Malabsorption of fat-soluble vitamins
2a. Decreases cyclosporine lvels
2b. Theoretical interaction with warfarin
2c. Levothyroxine should be dosed separate from orlistat
3. Severe liver injury
Nonadrenergic Agents
1. Examples
2. Restrictions
3. Contraindications
4. MOA
5. Side effects
Only FDA approved for short-term use
1. Phendimetrazine, Phentermine, Diethylpropion
2. Schedule III, IV, and IV, respectively due to addiction potential
3. Diabetes, HTN, and heart disease
4. Activate central noradrenergic receptors
5. Increased BP and HR, insomnia, nervousness, dizziness, dry mouth, nausea, constipation
Other drugs associated with short-term weight loss (6)
Bariatric Surgery
Defined as a weight loss surgery performed on people who are obese for the purpose of losing weight
Bariatric Surgery (Targeted Patient Population) [3]
1. Patients who are 80-100 or more pounds overweight
2. BMI > 40 or BMI of 35 AND a medical condition that is linked with obesity
3. Must have:
3a. Tried and failed to lose weight with other methods
3b. Agree to lifelong changes
3c. Agree to medical follow-up
Two Major Types of Procedures
1. Restrictive
2. Restrictive/Malabsorptive Combination
Restrictive Bariatric Surgery (3)
1. Vertical banded gastroplasty
2. Adjustable gastric binding
3. Restrictive procedures (in general):
3a. Small pouch - limits food intake
3b. Food passes through small hole to GI tract - slows emptying
Prevalance/Problems with Restrictive Bariatric Surgery (3)
1. Not as invasive
2. Less dramatic weight loss
3. Less nutrient deficiencies/changes in drug absorption
Restrictive/Malabsorptive Combination Surgery (2)
1. Biliopancreatic diversion
2. Roux-en-Y Procedure - Gastric Bypass
Prevalance/Problems with Restrictive/Malabsorptive Combination Bariatric Surgery
1. More weight loss
2. Increased risk of nutrient deficiencies/changes in drug absorption
Post Operative Consequences
1. Decreased GI tract = Reduced bioavailability of drugs
2. Much less HCl is produced during digestion
3. Digestive enzymes are decreased
4. Surface area greatly reduced
5. Absorption is greatly reduced
Medication Recommendations
1. NSAIDs, Salicylates, and Oral Biphosphonates
2. Extended or Sustained Release Products
3. Oral Antibiotics
4. Medications absorbed in the stomach or duodenum
5. Chronic medications for multiple disease states
6. Salt form of medications
7. Liquid formulations
1. Avoid
2. Avoid
Nutrient Deficiency proportional to:
Length of absorptive area and % of weight loss
Monitor patients closely for nutrient deficiencies and supplement appropriately
Other Post Operative Consequences (10)
Dumping syndrome
Cold intolerance
Hair loss
Gall stone formation
Post operative Hyperinsulinemic Hypoglycemia Syndrome
Bowel Obstruction
Serina is scheduled for bariatric surgery in 1 week. She currently suffers from sleep apnea, arthritis, osteoporosis, hypertension, hypothyroidism, and type 2 diabetes. She uses a CPAP machine at night for her sleep apnea. Her current medications include calcium carbonate 500 mg TID, ibuprofen 800 mg TID, metoprolol XL 100 mg daily, levothyroxine 100 mcg daily, and metformin XR 2000 mg daily. Which of her medication is LEAST likely to require adjustment IMMEDIATELY AFTER the surgery?
A. Ibuprofen
B. Metoprolol
C. Levothyroxine
D. Metformin