OBESITY


SUMMARY:

Basic approach:

  1. Rule out secondary causes of obesity
  2. Assess obesity-related health risk
  3. Rule out contraindications to weight loss
  4. Ensure pt readiness
  5. Pick appropriate tx, monitor progress
  6. Provide maintainance tx (very important given high risk of regaining weight;
    keep in mind importance of continuing pos. reinforcement even in this stage)

Benefits of weight loss: No clear data as of 1996 on long-term benefits of weight loss in obese pts,
though reduction in known risk factors for cardiac, etc. disease has been shown.

Success of weight loss: Avg. wt. loss 8.5kg after 21wks of tx with avg 5.6kg at 53wks of
followup (Ann. Int. Med. 119:688, 1993, cited in JAMA rvw)

See also Metabolic Syndrome

Identifying secondary causes of obesity for tx/referral

Assessing obesity-related health risk

Contraindications to weight loss treatment

Assessing pt's readiness

Treatment

Low-Carbohydrate diets

Pharmacologic Treatment

Surgical Treatment

 

I. Identifying secondary causes of obesity for tx/referral

  1. Hyperinsulinemia
  2. Hypothyroidism
  3. Cushing's disease
  4. Meds (steroids, tricyclics)
  5. Menopause (will tend to result in increase in central adiposity, but no way to impact this)
  6. Past sexual/physical/emotional abuse (increases risk of obesity)

II. Assessing obesity-related health risk--note that obesity-related excess mortality declines with age, becoming insignificant after 74y in one prospective cohort study of 320,000 Americans (NEJM 338:1, 1998--JW)

  1. BMI (weight in kg/square of the height in meters)
  1. Can't be calculated accurately for pts w/scoliosis, kyphosis, or other disorders that preclude accurate height measurement
  1. Comorbidities (conditions contributed to by obesity)
  1. HTN
  2. Other cardiovascular disease
  3. Dyslipidemias
  4. Type II DM
  5. Sleep apnea/hypopnea
  6. Osteoarthritis
  7. Infertility (male or female)
  8. LE venous stasis disease
  9. GERD
  10. Urinary stress incontinence
  11. Idiopathic intracranial hypertension (see also under HEADACHE)
  1. Other risk factors (conditions that increase health risk due to obesity and/or risk of obesity worsening, or require special caution)
  1. Waist-hip ratio > 1.0 in males or > 0.8 in females (waist = midway between lowest rib margin & iliac crest
    1. Shown to be a sig., independent risk factor for coronary events in an analysis of 8y f/u data on 44,702 women in the Nurses' Health Study (JAMA 280:1843, 1998--JW)
  2. Waist circumference > 39" in males of > 34" in females
  3. Recent onset of obesity (may be only temporarily remediable)
  4. Status post successful weight loss
  5. Bulimia (binge + purge) or binge eating disorder (binge only). Features of binge eating include:
  1. A sense of lack of control over an eating episode
  2. Eating more rapidly than normal
  3. Eating until uncomfortably full
  4. Eating large amounts of food when not feeling hungry
  5. Eating alone b/c of embarrassment over how much one is eating
  6. Feeling guilty, disgusted w/oneself, or depressed after overeating
  1. Depression, anxiety, or stress
  2. Sedentary lifestyle and/or inability to exercise

BMI-RELATED HEALTH RISK TABLE:

BMI Range Health risk based on BMI Risk if comorbid or other risk factors present
< 25 Minimal Low
25- < 27 Low Moderate
27- <30 Moderate High
30- <35 High Very high
35- <40 Very high Extremely high
40 or more Extremely high Extremely high

III. Contraindications to weight loss treatment

  1. Pregnancy or lactation
  2. Unstable mental illness
  3. Unstable medical conditions
  4. Anorexia nervosa
  5. Terminal illness
  6. Cholelithiasis (relative contraindication)
  7. Osteoporosis (relative contraindication)
  8. Cardiac disease

IV. Assessing pt's readiness

  1. Are there other life issues that will interfere w/ weight loss efforts?
  2. Is the pt willing/able to make a lifelong commitment to intense diet & exercise changes?

V. Treatment

  1. If minimal or low risk, weight loss is optional and/or not recommended
  2. Selecting appropriate target BMI
  1. Usually, 2 BMI units below current one is "realistic and practical" per AOA
  2. Majority of pts w/BMI > 30 lose 10-12% of body weight; most want to lose 20-30%; may not want to set goal too high b/c discouragement may impede efforts to maintain weight loss
  1. Diet changes to create an energy deficit
  1. All should be balanced in CHO, protein, and fat
  2. Risks/side f/x of dieting: fatigue, temporary hair loss, gallstone formation, gout, cardiac abnormalities (with very low calorie diet), electrolyte abnormalities, nutrient inadequacies (Fe, Ca, folate, protein), loss of lean body mass
  3. Healthy food choices (may decrease # of calories consumed)
  1. Low fat (including preparation techinques)
  2. High fiber (fruits and vegetables)
  1. How to calculate energy requirement (to calculate deficit diets)
  1. Male BMR: 10 x weight (kg) + 6.25 x height (cm) - 5 x age (y)
  2. Female BMR: 10 x weight (kg) + 6.25 x height (cm) - 5 x age (y) - 161
  3. Multiply by "activity factor": for light activity, 1.5 female; 1.6 male
  1. Moderate deficit: 500kCal/d deficit
  2. Low calorie diet: 1000kCal/d deficit
  3. Very low calorie diet: >1000kCal/d deficit (< 800kCal/d in diet)
  1. Should include at least 50g of CHO b/c if not, ketosis may develop and uric acid may rise, precipitating an episode of gout
  2. Should include 0.8-1.5g/kg ideal body wt/day high-quality protein
  3. Be careful if pt has Type I DM or cardiac disease
  1. Low-Carbohydrate diets
    1. In an 6mo uncontrolled study of 41 healthy pts (mean age 44, mean BMI 31.4) put on a very-low carbohydrate diet (25g/d until 40% target weight loss achieved then 50g/d), with no restriction of carolic intake, avg. weight loss was 10% total body weight (9kg); avg. BMI reduction was 3.2; 68% developed constipation; 63% developed halitosis (Am. J. Med. 113:30, 2002--JW)
    2. 132 morbidly obese pts (mean BMI 43) randomized to low-CHO diet (< 30g/day) vs. low-fat diet (< 30% calories from fat with 500 kCal/day deficit). Mean wt loss in low-CHO group @ 6mos was sig. greater (5.7kg vs. 1.8kg) (NEJM 348:2074, 2003--JW)
    3. 63 nondiabetic obese pts (mean BMI, 34) randomized to lowCHO diet (20g/d) vs. high-carb, low-fat, low-calorie diet (1200-1500 cal/day for women, 1500-1800 cal/day for men). Wt loss significantly greater in the low-carb at 6mos but no sig. diff. at 12mos. Insulin-sensitivity did not differ significantly between the groups (NEJM 348:2082, 2003--JW)
    4. In a meta-analysis/systematic review of 107 studies of low-carbohydrate diets (of various diet compositions, duration, and patient weight), degree of weight loss was associated with longer diet duration and restriction of calorie intake but not with reduced dietary carbohydrate content (JAMA 289:1837, 2003--Abst) 
    5. A low-carbohydrate diet vs. a low-fat diet was ass'd with sig. higher incidence of losing 10% or more of body weight (61% vs. 23%) in a 24-week randomized trial of 120 generally healthy but overweight adults (mean BMI 34) (Ann. Int. Med. 140:769, 2004--JW)
    6. A low-carbohydrate diet was ass'd with sig. greater weight loss at 6mos but no at 1y compared with a low-fat diet in a randomized trial in severely obese adults (mean BMI 43) (Ann. Int. Med. 140:778, 2004--JW)
    7. In a meta-analysis of five randomized trials comparing low-carbohydrate, non-calorie-restricted diets with low-fat, calorie-restricted diets, for minimum of 3mos, the low-carbohydrate dieters had sig. more weight loss at 6mos (by 3.3kg) and had sig. greater decreases in TG level (by 22 mg/dL) and increases in HDL (by 4.6 mg/dL). However, they also had sig. lower decrease in LDL (by 5.4 mg/dL); at 12mos, the differences in weight were not sig. (Arch. Int. Med. 166:285, 2006--JW)
  1. Physical activity
  1. Informal measures, e.g. taking stairs instead of elevator
  2. Formal exercise regimen
  1. Adapted exercise programs for limited individuals, e.g. chair dancing, H2O aerobics, etc.
  1. Lifestyle changes:
  1. For every patient!
  2. Self-monitoring of eating and exercise w/diaries
  3. Stress management, esp. finding alternatives to eating to deal w/stress
  4. Problem solving & "Stimulus control" to find & eliminate cues for unhealthy eating & underexercising (buying food when not hungry, etc.)
  5. "Relapse prevention" to identify high-risk situation & plan for minimizing the risk
  6. Using self-rewards to reinforce appropriate behavior changes
  7. Learning to elicit support from others & identify saboteurs
  8. "Cognitive restructuring," reducing self-defeating thoughts/feelings
  1. Pharmacologic tx: see below
  2. Surgical tx: see below
  3. Selecting amongst tx choices according to "health risk" (see above)
Health Risk Category Treatment Options
Minimal and low Healthy food choices and/or moderate deficit diet

Increased physical activity

Lifestyle change strategies

Moderate Above plus low calorie diet
High and very high Above plus pharmacotherapy and very low calorie diet
Extremely high Above plus surgical intervention

 

  1. Treatment specialists/programs
  1. Noncommercial
  1. TOPS (run by colunteers, $20 annual membership fee)
  2. Overeaters Anonymous (12-step volunteer)
  1. Commercial
  1. Diet Workshop (proprietary foods optional, maintenance program is free)
  2. Jenny Craig (proprietary foods required at first then become optional; maintenance $199/yr)
  3. Weight Watchers (proprietary foods optional; maintenance program is free)
  4. The Solution (through UCSF; maintenance is free)
  5. Slim-Fast: Self-help program w/shake; may be more effective than diet alone (Obes. Res. 4: 57S, 1996) and 66% maintenance of weight lost at 3y (Obes. Res. 4:7S, 1996)
  1. Other professionals
  1. RD's
  2. Exercise physiologists
  3. Clinical psychologists

 

PHARMACOLOGIC TREATMENT

Since obesity is a chronic disorder, short-term therapy is unlikely to do any good; unclear how safe and effective long-term (yrs) pharmacotherapy will be.

HHS recc's as of 12/97 re: pts exposed to fenfluramine or dexfenfluramine:

I. Catecholaminergic agents

  1. Increase availability of norepinephrine in CNS
  2. Response, if it will occur, is us. seen in first 4-6 weeks
  3. Amphetamines: high potential for abuse; rarely used
  4. Diethylpropion, mazindol: no good studies as of 1996
  5. Phentermine alone
  6. Over-the-counter preparations: phenylpropanolamine

II. Serotonergic agents (fenfluramine and dexfenfluramine)--Removed from US market 1997; click HERE for information about their clinical use

III.Medications for Binge Eating Disorder

  1. Sertraline, Fluvoxamine, Fluoxetine, and Imipramine have been shown to decrease binge frequency and increase weight loss c/w placebo (Am J Psychiatry 1998; 155:1756, Am J Psychiatry 2000; 157:1004, J Clin Psychiatry 2002; 63:1028, Int J Eat Disord 1999; 26:231, respectively)
  2. Topiramate 25-600mg/d (median dose 212mg/d) was ass'd with sig. fewer binges and sig. more weight loss than placebo in a randomized 14-wk trial in 61 obese patients with binge eating disorder (Am. J. Psych. 160:255, 2003--abst)

IV. SSRI's: very disappointing results with weight regain despite continued use

  1. Fluoxetine
  1. 60mg QD better than lower dosages
  2. 458 obese pts tx'd x 1y with fluoxetine vs. placebo; small but sig. diff in wt loss at 20wks, then slow regain; no diff. in wt loss at 1y, however (Goldstein et al. Int. J. Obes 18:129, 1994, cited in JAMA rvw)
  1. Sertraline
  1. Study of women who had been on a very-low-energy diet x 6mos; small wt. loss with sertraline vs. small wt. gain with placebo; advantage gradually declined and no diff. in weight loss at 6mos (Obes. Res. 3:549, 1995, cited in JAMA rvw)

V. Sibutramine 10-15mg QD (Meridia)

  1. Combined serotonin/norepinephrine reuptake inhibitor
  2. FDA-approved for tx of obesity, in conjunction w/reduced-calorie diet, in pts with BMI > 30 (> 27 if other risk factors present, e.g. HTN/DM)
  3. Clinical trials show sig. better weight loss than w/placebo (14lb vs.3.5lbs at 12mos in one study) per FDA press release
  1. 55 pts, 130-180% of ideal weight but o/w healthy, randomized to sibutramine 20mg QD vs.5mg QD vs. placebo x 12wks; all got caloric restriction, behavior modification, and exercise counseling. Sig. greater wt. loss w/20mg/d vs. either 5 or placebo (5.0kg vs. 2.9 vs. 1.4)
  2. 173 pts randomized to sibutramine 1-30mg/d or placebo over 24 wks;dose-dependent reduction in weight was seen; didn't plateau during the study period in 30, 20, and 15mg/d groups. Weight regain occurred upon d/c of meds (Obes. Res. 4:263, 1996--abst)
  3. 1047 pts on restricted calorie diet randomized to sibutramine 1-30mg/d vs. placebo; 24wk f/u showed dose-related increased weight loss w/sibutramine; avg. 5.3kg w/15 QD and 6.5kg w/30 QD (Int. J. Obes. 21 suppl. 1:S30, 1997--Med. Letter)
  1. Adverse effects
    1. Include insomnia, irritability, dry mouth, HA, and constipation (Clin. Pharm & Therap. 50:330, 1991--abst)
    2. Can also increase heart rate and BP; uncontrolled HTN is a contraindication (Med. Lett. 40:32, 1998)
    3. No known ass'n w/PPH or valvular disease
    4. May be associated with increased risk for cardiovascular events
      1. In a stufy in 10,000 pts with overweight or obesity and known (CV disease, type 2 DM, or another risk factor) randomized to sibutramine vs. placebo, over mean 3.4y f/u, mean weight reduction in sibutramine group was sig. greater (by 2kg) but incidence of (MI, nonfatal CVA, or cardiovascular death) was sig. higher in sibutramine group (11.4% vs. 10.0%) ("Sibutramine Cardiocascular Morbidity/Mortality Outcomes in Overweight or Obese Subjects at Risk of a Cardiocascular Event"  ("SCOUT") Trial; NEJM 363:972, 2010-JW)
  2. Not to be used in conjunction w/other serotonergic drugs, e.g. SSRI's, sumatriptan, lithium, meperidine, fentanyl, dextromethorphan, or MAOIs

VII. Drugs that block absorption of fat

  1. Orlistat (Xenical)--120mg TID prior to each meal containing fat
    1. Inhibitor or pancreatic lipase; decreases GI absorption of fat by about 30%
    2. Side effects include oily stools, flatus, fecal urgency; side effects are least with low-fat diet
    3. Associated with slight drops of levels of beta-carotene and vit. D levels; reversible with a multivitamin.
    4. In pooled data from 7 pre-approval studies, more cases of breast Ca noted among users than non-users or would be expected epidemiologically (9/747 vs. 1/579 on placebo); may have been a fluke--no such association seen in published trials (see below) (Med. Lett. 41:55, 1999)
    5. Contraindications: Malabsorption syndromes, Cholestasis
    6. Clinical studies
      1. In phase 3 trials, there was only a 3-4% diff. in mean weight loss between Orlistat & placebo over 1y of tx; both groups regained weight in the 2nd years. Did, however, produce sig. reductions in LDL and BP.
      2. 688 obese pts on calorie-restricted diets randomized to Orlistat 120mg TID vs. placebo; orlistat group had sig. greater weight loss at 1y (10.3 vs. 6.1kg); pts re-randomized and put on a calorie-maintenance diet x 1y; Orlistat was more effective than placebo at maintenance of weight loss. Those who got placebo after Orlistat regained most of weight during the placebo year (Lancet 352:167, 1998--JW)
      3. 322 obese pts with type 2 DM on mild calorie-restricted diets randomized to Orlistat 120mg TID vs. placebo; at 1y, mean wt. loss sig. greater in Orlistat group (6.2kg vs. 4.3kg) (Diab. Care 21:1288, 1998--JW)
      4. 892 obese adults (BMI 30-43) randomized to Orlistat 60-120mg TID vs. placebo x 2y; all had weight-rediction diet year 1 & eight-maintenance diet year 2. Orlistat group was at the end of year 1 randomized again to placebo vs. orlistat. Orlistat group had sig. greater weight loss in year 1 (8.8kg vs. 5.8kg) and sig. less weight regain in year 2; 79% of orlistat group had some GI side f./x (JAMA 281:235, 1999--JW)
      5. In a randomized trial in 635 obese patients randomized to orlistat 60mg TID, orlistat 120mg TID, or placebo x 2y.  At end of study, mean weight loss compared w/baseline among those who didn't drop out was 4.58kg, 5.16kg, and 1.54kg respectively (Arch. Fam. Med. 9:160, 2000--AFP)

VIII. Drugs that alter Glucose metabolism

  1. Metformin
    1. Ass'd with weight loss in many patients
    2. 11 of 14 obese hyperinsulinemic men with midlife weight gain tx'd with metformin & low-CHO diet had 5% or greater weight loss at 3mos; av wt loss @ 6mos was 21.2lb (paper presented by Harriet Mogul at Endocrine Society Meeting, reported in FP News 10/15/02)
  2. Rosiglitazone + Amylose-free diet
    1. Ass'd with average weight loss of 1.5lb/wk in women and 1.7lb/wk in men in a 36-week open-label pilot study of 40 nondiabetic hyperinsulinemic patients. Amylose-free diet involved avoiding "vegetables that grow undergroundm bananas, or foods enriched with maltodextrins or corn syrup, or foods made fom wheat, rice, rye, barley, and oats" (paper presented by Dr. Ritchie Shoemaker at Endocrine Society Meeting, reported in FP News 10/15/01)

IX. Drugs that increase thermogenesis, e.g. BRL 26830

X. Endocannabinoid receptor antagonists

  1. Rimonabant
    1. 3,040 pts with BMI > 27 randomized to rimonabant 5mg/d or 20mg/d vs. placebo x 1y; rimonabant group was re-randomized to continued tx vs. placebo x another 1y; at 2y, rimonabant 20mg/d group had sig. greater weight loss c/w placebo (7.4kg vs. 2.3kg) ("Rimonabant in Obesity-North Americal" Trial ("RIO-NA"; JAMA 295:761, 2006--AFP)
    2. In a study in 1,036 adults with BMI 27-40 and dyslipidemia randomized to rimonabant 5mg/d or 20mg/d vs. placebo x 12mos (all pts were prescribed a hypocaloric diet), the 20mg/d rimonabant recipients had sig. greater mean weight loss c/w placebo (6.7kg) as well as sig. greater reduction in waist circumference, increase in HDL level, and reduction in triglyceride levels (NEJM 353:2121, 2005--JW)
    3. Removed from U.S.market due to neuropsychiatric side effects

XI. Bulk-producing products (most are OTC) fill the stomach to suppress appetites

XII. Other medications for obesity

  1. Garcinia cambogia
    1. 135 overweight pts (mean BMI 32) randomized to G. cambogia (1500mg/d hydroxycitric acid content) vs. placebo x 12wks; no sig. diff. in weight loss or % body fat loss (JAMA 280:1596, 1998)
  2. Naltrexone + bupropion
    1. In a study in 1,742 obese pts with no DM or known cardiovascular disease randomized to (bupropion 180mg BID + naltrexone 8mg or 16mg BID) vs. placebo x 1y, in intention-to-treat analysis, mean weight loss was sig. greater in both active treatment groups (5.0% and 6.1% with 8mg and 16mg naltrexone doses, respectively, vs. 1.3% with placebo); adverse effects in the active-treatment group included nausea, vomiting, constipation, headache, dizziness, and dry mouth (Lancet 376:595, 2010-JW)

SURGICAL TREATMENT

I. Criteria for surgical tx (there are several; these are from Br. J. Surg. Rvw)

  1. Body weight > 200% ideal
  2. BMI > 39 kg/m2
  3. Minimum of 5y obesity
  4. No h/o alcoholism or major psychiatric disorder
  5. Failure of conservative therapy

II. General issues

  1. Discuss patient's expectations
  2. Rule out obesity-related endocrine disorders, including hypothyroidism and Cushing's disease
  3. Abdominal u/s to screen for cholelithiasis (if present, concomitant cholecystectomy is usually performed)
  4. Post-op dietitian consultation is important to make sure adequate protein/calorie intake is maintained (malnutrition and anemia have been reported post-op)
  5. Note that pts can circumvent the restriction on gastric intake by taking high-calorie liquids foods; this should be avoided
  6. Efficacy
  1. Overall, tend to lose 30-40% of body weight (mostly in 1st 6mos), compared w/4-9 for mod. reduced calorie diet, 10-15 for low calorie diet, and 15-20 for very low calorie diet, and probably keep it off better too
  2. In one series of 608pts, weight regain over 10-12y avg. 10-15% of initial weight lost (Ann. Surg 222:339, 1996-cited in AOA paper)
  3. In another series of 1,703 pts followed for 10y, weight loss was mostly maintained between 2y and 10y after surgery (mean decrease from baseline was 23% at 2y and 16% at 10y) (NEJM 351:2683, 2004--abst)
  1. Nutrition issues: supplement Fe, Ca, folate, and possibly B12
  2. Potential effectiveness at improving glycemic control in type 2 diabetes mellitus
    1. 150 patients with obesity (mean BMI 36 kg/m2) and type 2 DM (mean HbA1c 9.2%) randomized to roux-en-Y gastric bypass, sleeve gastrectomy, or medical therapy; At 12mos, both surgery groups had sig. higher incidence of reaching HbA1c of 6% or lower (42% and 37% vs. 12% in the medical treatment group). (NEJM 3/26/2012, e-pub ahead of printing at: http://dx.doi.org/10.1056/NEJMoa1200225)

IV. Current techniques focus on gastric restriction to create a small-capacity gastric pouch; this limits intakes of solids but not liquids; randomized trials have shown sig. Greater wt. loss than with supervised very-low-calorie diets (NEJM 310:352, 1984, cited in BJS rvw.); good f/u studies up to about 2y post-op

III. Small bowel bypass

  1. Largely superceded by other procedures (see below)
  2. Associated with numerous complications, including diarrhea, perianal discomfort, electrolyte abnormalities, malabsorption of fat-soluble vitamins and vitamin D, and liver failure

V. Vertical gastroplasty

  1. A vertical partition is stapled between lesser curve and fundus/body
  2. Morbidity/mortality < 1%
  3. Complications:
  1. Stenosis of the gastric stoma (4-25%; can be dilated endoscopically)
  2. Vomiting due to too-rapid food intake
  3. Gastric leakage (quite serious; occurs in < 1%)
  4. Severe ulcerative esophagitis (rare)
  5. Peptic ulceration (1-8%)
  6. Regain of weight due to disruption of staple line or dilatation of gastric pouch (pts suddenly notice they can eat and not get full)
  1. Outcomes: 50% of pts lose at least 50% of their excess weight in first 12mos

VI. Horizontal gastroplasty

  1. Stapled horizontal partition to reduce gastric volume
  2. Complications: probably the same as vertical gastroplasty, though review in BJS didn't say; may be less "mechanically reliable" than vertical gastroplasty, and vertical has been done after failed horizontal

VII. Roux-en-Y Gastric bypass

  1. Upper stomach is stapled horizontally; drainage into a jejunal loop in a Roux-en-Y Achieve wt. loss both by restriction of volume of ingested food and interference with absorption due to biliopancreatic bypass
  2. Ass'd with greater weight loss than other 2 procedures but more demanding technically and ass'd with higher rates of morbidity, including risk of dumping syndrome (7% in one series; may be a deterrent against eating osmotically dense foods, e.g. sweets), anastamotic leakage (5% in one series), and stomal ulceration
  3. Higher rates of nutritional deficiency; need for monthly B12 injections
  4. In a series of 191 pts (median BMI 49 kg/m2), 10% experience postoperative complications (mostly ventral hernia, wound infection, small bowel obstruction, & pneumonia); average wt. loss at 1y was 52kg (Mayo Clin. Proc. 75:673, 2000--JW)

VIII. Laparoscopic gastric banding

  1. Involves placement of a silicone band around the stomach; the band is connected to a subcutaneous injection port into which saline can be injected or aspirated to adjust the diameter of the "stoma" through which food passes.
  2. In a study in 80 pts with BMI 30-35 randomized to laparoscopic gastric band placement vs. intense non-surgical weight loss program (behavior mod + orlistat), after 2y f/u, % of excess weight lost by the surgery group was sig. greater than that lost by the non-surgery group (87.2% vs. 21.8%) (Ann. Int. Med. 144:625, 2006--JW)

IX. Comparisons of different techniques

  1. In a nonrandomized prospective study of 206 pts undergoing laparoscopic Roux-en-Y gastric bypass or laparoscopic gastric banding (matched for age, sex, and BMI), banding pts had sig. shorter length of hospital stay and sig. fewer early reoperations than the bypass group, though late complications were sig. more common. Bypass pts had sig. greater % of excess weight lost at 24mos (54% vs. 42%) (Ann. Surgy 240:975, 2004--JW)
  2. In a study in 197 obese pts randomized to laparoscopic Roux-en-Y gastric bypass vs. laparoscopic banding, the bypass group had sig. higher incidence of complications in first 30d (6% vs. 2%) and at 31-90d (26% vs. 12%), but bypass pts lost a greater % of excess weight at 4y (68% vs. 45%) (Am. J. Surg. 250:631, 2009-JW)

X. Post-surgical long-term management

  1. Depending on the procedure, there may be greater or lesser propensity to poor absorption of macro- and micronutrients (the latter more common, particularly iron, vitamin B12, calcium, and vitamin D)
  2. Long-term vitamin and mineral supplementation may be indicated including calcium and vitamin D
  3. Consider monitoring for:
    1. Hypoalbuminemia
    2. Ketosis
    3. Osteoporosis

SOURCES INCLUDE: