Obesity/Weight Loss

Patient with history of DM type 2, HTN, HLD, obstructive sleep apnea, non-alcoholic fatty liver disease presents due to weight gain. Patient is unhappy with her current weight. Does not exercise and reports inadequate fruit/vegetable consumption. Greater than 25% of calories consumed between evening meal and breakfast. Reports changes in routine leading to change in location where food is purchased, increased sedentary behavior, increased screen time, sleep deprivation. Medications include amlodipine, sulfonylureas, thiazolidinediones, amitriptyline, mirtazapine, paroxetine, antipsychotics. BMI > 30 kg/m^2.

  • Obtain TSH, HbA1c

  • Counseling

    • Diet

      • No diet has been shown to be superior for weight loss provided it reduces the number of calories consumed per day

      • Select a diet that is sustainable and, ideally, increases fruit and vegetable consumption

      • Reduce intake of beverages containing sugar, alcohol

      • Do not consume fewer than 800 Calories per day without medical supervision

    • Exercise: CDC recommends 150 minutes of moderate exercise per week including 2 days of strength training that work all major muscle groups

    • Additional risk factors for weight gain

      • Discount foods that often contain added sugar, salt

      • Night eating syndrome: Greater than 25% of calories consumed between evening meal and breakfast

      • Small changes in physical activity, e.g. energy saving appliances, decrease in vigorous physical activity by as little as 5-10 minutes per day

      • Increased screen time leading to sedentary behavior +/- inadvertent calorie consumption

    • Factors with minimal impact on overall weight (~5 pound weight gain or less): Healthy pregnancy, oral contraceptives

  • Initial interventions

    • Calculate current BMI and target weight

    • Substitute weight neutral medications if possible (see notes)

    • Perform motivational interviewing concerning healthy lifestyle changes

    • Log calorie consumption and exercise habits x 1 week and follow-up to review results

    • Consider medical/surgical therapy (see below) after instituting lifestyle change and ruling out other medical disorders (see below)

Medical Disorders Associated with Weight Gain

Polycystic Ovarian Syndrome (PCOS)

Cushing disease

  • Physical exam: Facial erythema, buffalo hump, abdominal stretch marks, bruising, and thin arms/legs

  • Verify no exogenous glucocorticoids

  • Concern for diagnosis per physical exam: Obtain 24-hour urinary free cortisol (UFC) excretion x 2 measurements

Binge eating disorder

  • Criteria (DSM 5)

    • Recurrent and persistent episodes of binge eating associated with three (or more) of the following: Eating much more rapidly than normal, eating until feeling uncomfortably full, eating large amounts of food when not feeling physically hungry, eating alone because of being embarrassed by how much one is eating, feeling disgusted with oneself/depressed/very guilty after overeating

    • Marked distress regarding binge eating

    • Absence of regular compensatory behaviors (such as purging)

  • Treatment

    • Refer for counseling

    • Start escitalopram 10 mg daily and increase to 20 mg daily after 1 week

Medical/Surgical Therapy for Persistent Obesity

  • BMI > 30 with < 5% weight loss after 6 months: Consider oral therapy

    • History of DM: Start liraglutide 0.6 mg sub-Q daily and increase dose by 0.6 mg at weekly intervals until reaching maximum dose of 3 mg qd

    • No history of DM and

      • No cardiovascular risk factors: Start phentermine-topiramate 3.75-23 mg daily x 14 days. Increase to 7.5-46 mg daily x 12 weeks before re-evaluating weight loss. Discontinue if < 3% weight loss during that time.

      • Cardiovascular risk factors: Start lorcaserin 10 mg BID and re-evaluate after 12 weeks. Patient counseled about risk of anal leakage with medication.

  • BMI > 40: Discuss referral to bariatric surgery program

Notes

  • Obesity classification based on BMI (kg per m^2): Class 1 (30.0-34.9), Class 2 (35.0-39.9), Class 3 (40 or greater)

  • Complications of obesity include DM type 2, HTN, HLD, obstructive sleep apnea, non-alcoholic fatty liver disease

  • Medication classes associated with weight gain and alternatives

    • Antidepressants

      • Promote weight gain: Amitriptyline, mirtazapine, paroxetine

      • Weight neutral: Most SSRIs, e.g. escitalopram, fluoxetine

      • Promote weight loss: Bupropion

    • Weight neutral antipsychotics: Aripiprazole (Abilify), haloperidol, and ziprasidone (Geodon)

    • Mood stabilizers: Lithium promotes weight gain while oxcarbazepine is weight neutral

    • Blood pressure agents: Amlodipine promotes weight gain while ACE inhibitors are weight neutral

    • Diabetes medications

  • Treatment

    • Consider drug therapy in the following cases

      • BMI of 30 or greater

      • BMI of 27 or greater with cardiovascular comorbidities

      • Failure to lose 5% of total body weight after 3-6 months of comprehensive lifestyle change

    • Weight loss medications

      • Phentermine-topiramate has greater efficacy that lorcaserin or liraglutide but comes with increased cardiovascular risk.

      • Orlistat 120 mg TID with fat-containing meals is another option with efficacy similar to that of lorcaserin; drawbacks include anal leakage. Patients should avoid wearing white pants when taking the medications.

    • Bariatric surgery (see below)

  • Bariatric surgery

    • Without bariatric surgery, annual probability of achieving BMI < 30 in patient with BMI 40 to 44.9 is 1 in 1290 for men and 1 in 677 for women (JAMA 2017)

    • Relatively safe and reduces obesity-related conditions, e.g. all-cause mortality, myocardial infarction, stroke

    • Post-surgical care