Obesity Management

We Start With a Case…

32 y.o. female with history of generalized anxiety disorder, migraines without aura, abnormal Pap smears, and heavy/irregular menstrual bleeding presents for annual well adult visit

As she is being roomed, you receive the following information:

  • Vitals: HR 82, BP 147/82, T 97.9, RR 14
  • Height: 164.5 cm (~ 5’5”)
  • Weight: 112 kg (246 lb, 12 oz)
  • BMI: 41.37 kg/m²

Complications of Obesity

Further complications: 

  • Psychological: weight discrimination, public stigma, depression
  • Infection: Individuals with obesity are more likely than normal-weight individuals to have respiratory complications during influenza season and are more likely to be hospitalized with influenza. Observational data link obesity with increased morbidity and mortality from COVID-19
  • Greater BMI is associated with increased rate of death from all causes and from cardiovascular disease

Screening

Body mass index (BMI)

  • BMI = body weight (in kg) ÷ height (in meters) squared
    • Easy to measure, reliable, and in general, correlates with percentage of body fat and body fat mass
    • May overestimate adiposity in individuals with higher lean body mass (e.g., very muscular individuals such as professional athletes or bodybuilders)
    • May underestimate adiposity in older persons due to loss of muscle mass associated with aging

Waist circumference (particularly for BMI 25-35)

  • ≥40 in for male sex; ≥35 in for female sex
  • Measurement of abdominal obesity and provides independent risk information that is not accounted for by BMI
  • Patients with abdominal obesity (central adiposity, visceral, or android obesity) are at increased risk for heart disease, diabetes, hypertension, dyslipidemia, NAFLD, and have higher overall mortality rates

  • Measure waist circumference by locating the top of the iliac crest, placing flexible measuring tape around the abdomen at the level of the iliac crest, measuring tape parallel to floor, and measuring at end of expiration. 

Also pertinent: 

  • Blood pressure 
  • OSA (STOP-BANG score)
  • Labs: 
    • A1c, fasting glucose (diabetes)
    • TSH (hypothyroidism) 
    • Liver function tests (NAFLD)
    • Lipid panel (dyslipidemia)

USPSTF: All adults (as well as children and adolescents >6) should be screened for obesity

Also consider screening for other factors that may interfere with treatment: 

  • Mental Health (PHQ9, Adult ADHD Symptom Rating Scale)
  • Eating disorder (Binge Eating Scale, EDE-Q)
  • Other sleep disorders
  • Chronic pain

Back to the Case…

  • BMI: 41.37 kg/m² 
  • Blood pressure: 147/82 (consistent with prior measurements)
    • Started on HCTZ
  • OSA screening: did not obtain 
  • Labs: 
    • AST/ALT: 108/114 (elevated) – ultrasound revealed hepatic steatosis and fibrosis
    • A1c: 6.0 (pre-diabetes)
    • Lipid panel: TC: 160, LDL: 93, HDL: 39 (low), TG: 142

What’s Next?

  • ASK permission to discuss weight and to set-up a management-focused follow up appointment
  • ASSESS readiness to make changes

5 Tenets of Weight Management

  1. Diet
  2. Exercise
  3. Behavioral intervention
  4. Pharmacologic therapy
  5. Referral for bariatric surgery/procedures

Diet

Pertinent history:

  • “Walk me through your average day of eating” 
  • 24-hour diet recall 
  • Specifics:
    • Number of meals and snacks in a typical day 
    • Timing of meals and snacks 
    • Types of foods eaten daily (any specific restrictions such as meat, lactose, gluten, etc)
    • Beverages (including soda, coffee, juice, alcohol) 
    • Fast food 
    • Ordering out vs cooking at home
    • “Problem foods”

The best diet is one that is safe, effective and realistic for the patient. 

  • Consider cultural norms, food preferences, time constraints, financial constraints, cooking skills/equipment

Diet should contain less energy (calories) than what is required for daily maintenance in order to achieve weight loss. 

  • Recommendation: 1200-1500 kcal/day female sex, 1500-1800 kcal/day for male sex 
  • Decrease by another 300 kcal/day if weight exceeds 150 kg

No significant differences between low-fat, low-carb, high-protein, or low glycemic index diets in the long run. 

General rules of thumb: 

  • LIMIT/AVOID:
    • Highly processed foods
    • Foods of minimal nutritional value – sweets (candy, cake, pie), “junk food snacks” (chips)
    • Energy-dense or sugar-sweetened beverages: soda, juice, cream, alcohol
  • ENCOURAGE:
    • Healthy proteins and fats, vegetables, leafy greens, fruits, nuts, legumes, whole grains
    • Complex carbohydrates over simple sugars
    • High-fiber foods
    • Reading food labels
  • Quality of calories is very important when reducing your quantity of calories!

MyPlate: MyPlate comes from the USDA (US Department of Agriculture), an excellent website with many resources for patients including personalized meal plans and calorie intake recommendations, information about all the different food groups and serving sizes, shopping lists and recipes, and even recommendations for different age groups and life stages (toddlers, pregnancy/breastfeeding, picky eaters, etc. The above infographic shows the proportions of food groups that should make up your average plate.

Intermittent fasting:

  • Eating plan that alternates between fasting and eating on a regular schedule
  • Alternate-day fasting, whole day fasting, time-restricted eating 
  • Many studies to suggest that this does promote weight loss 
    • Trepanowski et al (JAMA 2017): Trial with 100 individuals – alternate day fasting did not produce superior weight loss, weight maintenance, or cardioprotection over calorie restriction 
  • Some evidence to suggest it may be better for insulin sensitivity and and loss of abdominal fat (though data is conflicting)
  • Caution in diabetes (especially with sulfonylureas or insulin)

Exercise

HPI questions: 

  • How many days per week do you exercise? 
  • What type of exercise?
  • How intense is your exercise? (Would you have difficulty having a conversation during it?) 
  • How many minutes per day? 
  • Do you enjoy exercise? 
  • Non-exercise activity thermogenesis (NEAT) = series of continuous movements that are not vigorous exercise activities but contribute to energy expenditure throughout the day
    • Ex: walking, climbing stairs, fidgeting, singing, laughing, cleaning, standing, gardening, mowing the lawn, etc. 

Pros & Cons: 

  • Generally, exercise alone is only moderately beneficial for weight loss 
    • It takes a considerable amount of time and effort to expend enough calories via physical activity that results in noticeable weight loss (100 calories per day in exercise = 700 per week → would take about 5 weeks to lose 1 lb of fat, which is equivalent to approximately 3500 calories)
  • Tends to add only mild benefit when added to calorie-restriction diets 
    • Even when accounting for intensity and duration of exercise 
  • Important in maintaining weight loss after weight reduction 
  • Even without significant weight loss, physical activity has many benefits: 
    • Reduces risk of CAD events/mortality, improves lipid profile, reduces blood pressure, reduces inflammation
    • Reduces abdominal fat
    • Bone health, functional status
    • Improves glycemic control and insulin sensitivity

Move Your Way is a great website that offers resources for exercise. Also has an app with an activity tracker and helpful resources for patients for get ideas for activity.

To exercise for weight loss, the goal is to increase energy expenditure by 1000 to 1200 calories per week, or slightly more than 150 calories per day.

An objective measurement of energy expenditure should be used since people overestimate their energy expenditure from activity. The amount of energy expended depends upon the duration and intensity of the exercise and the subject’s initial weight.


Behavioral Therapy

Per the 2013 AHA/ACC/TOS Guideline for the Management of Overweight and Obesity in Adults

The most effective behavioral weight loss treatment is an in-person, high-intensity (ie, ≥14 sessions in 6 months) comprehensive weight loss intervention provided in individual or group sessions by a trained interventionist. The principal components of an effective high intensity, on-site comprehensive lifestyle intervention include 1) prescription of a moderately reduced-calorie diet, 2) a program of increased physical activity, and 3) the use of behavioral strategies to facilitate adherence to diet and activity recommendations… Comprehensive lifestyle intervention consisting of diet, physical activity, and behavior therapy produces average weight losses of approximately 8 kg in a 6-month period of frequent, in-person treatment. This approximates losses of 5%-10% of initial weight.

Trained interventionists include mostly health professionals (eg, registered dietitians, psychologists, exercise specialists, health counselors, or professionals in training) who adhere to formal protocols in weight management. 

Digitally delivered programs such as apps can lower costs and expand treatment reach; their efficacy is likely to improve further with the addition of new technologies for monitoring food intake, activity, and weight.

  • My Fitness Pal (blue) and Lose It (orange scale) allow you to track food and exercise.
  • Nourishly (green bird) focuses on eating mindfully. Users can record their emotions and hunger levels before eating, and fullness levels after eating, with no numbers involved. 
  • WW provides a points-based dietary plan of conventional foods with support from in-person meetings or online sessions. A 2015 review identified nine studies that supported the program’s efficacy, with mean weight losses ranging from 3-7% of initial weight at 6-12 months
  • Noom (sun) offers a personal coach to help people work toward weight loss goals. It uses a psychology-based approach to help users navigate their environment, identify triggers for emotional eating or cravings, and works with users to practice healthy diet and lifestyle habits. 

Pharmacotherapy

Obesogenic pharmacotherapy: 

Let’s first talk about obesogenic pharmacotherapy, which is incredibly common in the US. In fact, 20.3% of adults in the US are taking obesogenic pharmacotherapy, including

  • Beta-blockers: atenolol, propranolol, metoprolol
  • Diabetes medications: sulfonylureas, thiazolidinediones, insulins, meglitinides
  • Anticonvulsants: carbamazepine, gabapentin, valproate
  • Antidepressants: amitriptyline, paroxetine, mirtazapine 
    • Check out this decision aid for making the best choice for your patient!
  • Anti-inflammatory medications
  • Antipsychotics
Source: Hales CM, et al. Use of prescription medications associated with weight gain among US adults, 1999-2018: A nationally representative survey. Obesity (Silver Spring). 2022 Jan;30(1):229-239

Obesogenic pharmacotherapy has been shown to decrease the ability to respond to weight loss programs and laparoscopic sleeve procedures. 

Weight-loss Therapy: 

Regarding weight loss medications, pharmacotherapy should be considered in patients with BMI >27 with comorbidity (e.g., HTN, dyslipidemia, T2DM, OSA) or BMI >30 without comorbidity. 

FDA-approved medications for chronic weight management include

  • GLP-1 Receptor Agonists: Semaglutide, Liraglutide
    • ADE: nausea, diarrhea, vomiting, constipation, abdominal pain, HA, fatigue, dyspepsia, dizziness
    • Black box warning for thyroid C-cell tumors (contraindicated in patients with personal or family history of medullary thyroid carcinoma or MEN type 2)
  • Naltrexone ER / Bupropion ER
    • ADE: nausea, constipation, HA, vomiting, dizziness, insomnia, dry mouth, diarrhea
    • Black box warning for increased suicidal ideation
    • Contraindicated in HTN, chronic opioid use, seizure disorder, anorexia/bulimia, MAOI inhibitors
  • Phentermine / Topiramate ER
    • ADE: paresthesias, dry mouth, constipation, URI, HA, insomnia, dizziness, sinusitis, nausea, back pain, fatigue, diarrhea
    • Contraindicated in pregnancy, glaucoma, hyperthyroidism and within 14 days of MAOI inhibitors
  • Orlistat
    • ADE: oily spotting, flatus with discharge, fecal urgency, fatty/oily stool, oily evacuation, incontinence
    • Contraindicated in pregnancy or with malabsorption issues, cholestasis

Which medication should we choose?

How should we define success with pharmacotherapy?

  • Weight loss >5% of body weight at 3 months + Safely tolerating medication

Bariatric Surgery

Source: UpToDate

Bariatric surgery is associated with greater weight loss and improved maintenance of weight loss as well as improvement in obesity-related comorbidities. 

  • Indications for referral: BMI > 35 with comorbidity or BMI >40 without comorbidity

Weight Maintenance

Weight loss is very difficult to maintain. The body develops a “set point” of adipose tissue mass, and after weight loss, counter-regulatory hormones are secreted to re-establish the higher body weight. This dates back to defending the body against food scarcity – the capacity to store excess energy as fat was once critical to survival.

Regular exercise: You actually need more exercise to maintain weight loss (200-300 min per week). When you lose weight, there is a reduction in energy expenditure caused by weight loss itself (in activities, plus your metabolic rate) because this is a time of “food scarcity” and your body is trying to conserve energy. Need to make up for this through physical activity. 

How to succeed in maintenance?

  • Self-weighing
  • Larger initial weight loss >2 kg in 4 weeks
  • Consumption of reduced calories ~1400 kcal/day
  • Low fat diet
  • Regular physical exercise
  • Attendance at a weight loss program or lifestyle intervention program
  • Belief that weight can be controlled

Take-Home Points!

  • Review medication regimens and assess if there are medications that affect weight gain
  • Who can start pharmacotherapy? BMI >27 with comorbidity or BMI alone >30 
    • FDA-approved regimens: GLP-1 agonist, Naltrexone/Bupropion, Phentermine/Topiramate, Orlistat
  • Discuss side-effects, comorbid conditions/associated symptoms to determine the best regimen
  • Utilize our clinical pharmacists! 
  • Success = >5% weight loss
  • REFER TO BARIATRIC SURGERY EARLY! Bariatric surgery helps lose weight/maintain weight loss and reduce co-morbid conditions
    • Who to refer? BMI >35 with comorbidity or BMI alone >40

Blog post based on Med-Peds Forum talk by Lindsey Mahoney, PGY4