The number of gastric surgeries performed for the treatment of obesity is now over 200,000 per year in the United States alone (almost an 800 percent incease in the past 10 years). In the face of this rapid increase, it is important to examine exactly which people might benefit from surgery as opposed to more "traditional" medical therapies for obesity. You can jump to the bottom of the article for some very useful news reports about the surgery, its risks and its benefits.
More than 50% of Americans are overweight and 30 percent or more are "obese." Nearly all experts agree that the prevalence of obesity will rise and soon reach epidemic proportions.(1) As a result of this increase, pharmacologic and surgical treatments for obesity have become more numerous and more widely used.
How do current drug therapies for obesity work?
Most of the drugs approved by the FDA for the treatment of obesity work by suppressing the appetite. This is the mechanism of action for phentermine (Adipex, Pro-Fast, Fastin), sibutramine (Meridia), and diethylpropion (Tenuate). Orlistat (Xenical) has a different mechanism; it reversibly binds to the enzyme lipase, and, thus, preventing the digestion and absorption of some dietary fats. This prevents adsorption of dietary fat and leads to a loss of 30% or more of fat calories through the stool.
Unfortunatey, there are no "head-to-head" studies that compare weight loss drugs with each other. Several comparisons of studies done with individual drug treatments have been done by the Agency for Healthcare Research and Quality do not show that any one drug is more effective than another.
• One comparison showed that the main difference in weight loss with Meridia (compared with placebo) was 3.43 kg at 6 months. At 12 months, the difference was 4.45 kg. Sibutramine was associated with modest increases in heart rate and blood pressure, a very small improvement in glycemic control among persons with diabetes, small increases in high-density lipoprotein cholesterol levels, and reductions in triglyceride levels.
• A similar comparison of orlistat-versus-placebo studies found that patients treated with the Xenical alone lost 2.51 kg at 6 months and 2.75 kg at 12 months. Some Xenical patients experienced diarrhea; flatulence; and bloating, abdominal pain, and dyspepsia (with relative risks of 3.4%, 3.1%, and 1.5%, respectively).
• In other meta-analyses, when compared with participants who received placebo, those treated with phentermine lost an additional 3.6 kg of weight at 6 months. Those who were given diethylpropion lost on average 3.01 kg by the sixth month.! Data on side effects or adverse effects were not reported.
• A study comparing fluoxetine (Prozac) versus placebo showed a mean weight loss of 4.74 kg at 6 months and 3.05 kg at 12 months. However, an increase in nervousness, sweating, and tremors; nausea and vomiting; fatigue, asthenia, hypersomnia, and somnolence; insomnia; and diarrhea in patients who took Prozac was noted, when compared with those who received placebo (with relative risks of 6.4, 2.7, 2.4, 2.0, and 1.7, respectively).
• Pooled results of 3 studies of bupropion (Welbutrin) showed that the average weight loss was 2.8 kg. The adverse effects included dry mouth and insomnia.
• Compared with placebo-treated patients, those who took topiramate (Topomax, an anti-seizure medication ) in 6 studies for weight loss lost 6.5% of pre-treatment weight. The most common side effects were paresthesias (4.9%) and taste perversion (9.2%).
• Only 1 study of zonisamide (Zonegran, another anti-seizure medication) has been done for weight loss. Over 32 weeks, treated patients lost an average of 6% of baseline body weight, compared with 1% for those given placebo.
Bariatric Surgery
Malabsorptive (bypass) surgeries reduce the amount of nutrients that is absorbed from a meal. Gastric banding procedures restrict the size of the stomach and thus limit the amount of food a patient can consume in a single meal.
Study results. In randomized controlled trials (RCTs), gastric bypass surgery resulted in greater weight loss than did gastroplasty. There was no clear difference in mortality or complications between the various procedures. Mortality following bariatric surgery was less than 1% in RCTs and about 2% in case series. Overall, the rate of complications ranged from 10% to 20%; most of the adverse effects were mild (eg, nutritional deficiencies) and responded to conservative therapy.
The Internation Association for Size Acceptance has this evaluation on its web site:
"WLS has at least a 40% complication rate and 2% death rate. Rapid weight loss, whether from dieting or from WLS, affects muscle more than fat, including heart muscle. The long term results of the procedure could lead to death from heart-related complications. Side-effects can include but are not limited to painful gastrointestinal distress, leaking of gastric juices into the chest cavity, infection, deterioration of teeth (erosion of enamel caused by repeated vomiting), flatulence, mineral and nutrient deprivation (especially potassium), uncomfortable and highly odorous bowel movements and/or loose stools.
WLS recipients can and often do regain the weight they lost, plus more, usually within five to ten years. For example, It is possible to stretch stomach tissue left after stapling, which defeats the purpose of the procedure."
The ISFA also has a wonderful discussion on their site about how you can be "fit at any size." I agree with their premise: a healthy lifestyle is much more important than a number on a scale. However, in my opinion, one does not necessarily exclude the other. I believe that living a healthier lifestyle - i.e. becoming more active and eating a better diet - will result in weight loss. But weight loss is not the objective. Healthy living is the primary goal.
Commentary:
An observational study demonstrated that surgery is more effective than medical therapy for weight loss and control of certain comorbid conditions in patients with a body mass index (BMI) of 40 or higher. In the Swedish Obese Subjects (SOS) study (9,10), the average weight loss at 8 years' follow-up among 251 surgically treated patients was 20 kg, or 16% of body weight. However, the average weight did not change among the 232 patients in the study who received medical therapy. In addition, 24 months after surgery, the prevalence of obesity-related comorbid conditions was markedly lower in the surgically treated patients.
The weight loss outcomes reported in various randomly-controlled trials that compared different procedures suggest that surgery may be the most effective obesity treatment for persons with a BMI higher than 40. However, these studies cannot be considered completely conclusive because the studies did not directly compare surgery with medical therapy.
Greater weight loss was reported in surgical studies than in studies of drugs and/or dietary therapy for obesity (weight losses of 20 to 40 kg at 1 or 2 years in surgical studies vs 2 to 5 kg in pharmaceutical studies). Again, conclusive direct comparisons cannot be made across the studies
What I believe: I absolutely believe that there is a place for bariatric surgery in the treatment of severe obesity. I have and would continue to recommend consideration of bariatric surgery for any patient who is "morbidly obese" (that is, having a BMI of more than 40). I would lean even more firmly in the direction of bariatric surgery if the patient were unable (not unwilling - unable) to adhere to a medical approach combining dietary modification, behavior modification and increased physical activity. I do not, however, feel that any otherwise healthy patient consider bariatric surgery with a BMI less than 40 unless there was some significant overriding medical reason or disability.
I urge everyone considering this procedure to, before making a decision about surgery for weight loss, read everything you can about the procedure and other patients' experiences There are several discussion groups that you can join anonymously. On Yahoo, Meriter Health Systems, and on MSN. Do some research and find out if the local surgery group that you select has a support group. Most of the more reputable surgical groups that do enough of these procedures have monthly meetings for people who have had or plan to have the surgery. Go to a couple of meetings to ask questions. Discuss the option with your personal physician and bring a list of questions. Your personal physician will give you their opinion on the procedure and why it may or may not suitable for you.Click on this link for some frequent questions and answers (FAQs) about bariatric surgery.
For the facts about obesity (bariatric) surgery, this excellent review by Rachel Brand of the Scripps Howard News Service gives an unbiased look at risks and benefits of the surgery. Also, I highly recommend this article by Karen Collins, a regular health commentator on MSNBC. It is excellent.
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Albright Bariatric Clinic