Weight Loss Surgery: Background And Results
Bariatrics: Reducing The Health Dangers Of Obesity
Gastric reduction surgery, such as Roux-en-Y (RGB) and Lap-Band (AGB) is now a major treatment for severe clinical obesity. To understand why, here are the facts about weight-related health. An estimated 3 out of 10 American adults are obese, meaning, they have a body mass index (BMI) of 30 or higher. Of these, roughly ten million are seriously obese (BMI 35-40), six million suffer from morbid obesity (BMI 40-50) and a smaller number suffer from super-obesity (BMI > 50). Morbid obesity (the basic threshold for candiates for bariatric surgery) is a chronic disease typically accompanied by a wide range of medical, psychological and physical co-morbidities. The latest evidence shows that obesity kills 112,000 Americans each year. According to the American Society For Bariatric Surgery, obese patients have a 50-100 percent increased risk of death from all causes, (500-1000 percent for super-obese, 500 percent for obese diabetics) compared with normal-weight individuals. Roughly 80 percent of patients with type 2 diabetes are reported to be obese, hence the new word “diabesity”, and morbid obesity is the largest environmental cause of diabetes in a population. Obesity is also a key symptom in “metabolic syndrome”, a cluster of symptoms from which an estimated 47 million Americans suffer. The rise in bariatric operations is a response to the life-threatening health consequences of the obesity epidemic, especially because studies show that seriously obese individuals find it almost impossible to achieve a healthy weight by tradtional weight loss methods involving calorie-controlled diets and exercise.
How Does Weight Loss Surgery Compare With Diets And Obesity Medication?
Research studies show that severely obese patients do not achieve medically significant long term weight loss by traditional dietary methods. On average, they lose 5.5 pounds over 12 weeks, of which most is regained with 12 months. A four-year study of patients on obesity drugs, showed a final average weight loss of three pounds per person. By comparison, most studies into the weight reduction achieved by bariatric patients indicate significant weight losses with corresponding improvements in health. Long term studies of weight loss achieved by bariatric surgery are rarer, and much depends on patient attitude and the degree of post-operative support offered, but surgical treatment of obesity seems to offer a far higher chance of success than non-surgical methods.
When Is Weight Loss Surgery Successful?
For bariatric surgery to be successful, a patient must lose 50 percent of their excess body weight, and keep it off in the long term. Therefore, in the case of a patient who is 200 pounds overweight, the gastric bypass or lap-band operation is considered successful if the patient loses at least 100 pounds and keeps it off long-term (> 6-10 years).
Results of gastroplasty (stomach stapling) and gastric banding – that is, restrictive surgeries – typically show an average loss of 50-60 percent of excess body weight at 12 months, followed by a slow weight gain thereafter. Five years after the operation, only 50 percent of patients have successfully kept the weight off, and at 10 years, as few as 26 percent of patients report successful weight maintenance. Recent studies show that lap-band bariatric operations can extend the weight loss over 2 to 3 years.
Results of Roux-en-Y, Biliopancreatic Diversion and Duodenal Switch gastric bypass surgeries – the malabsorptive type of weight loss surgery – are generally better. Initial weight reduction after Roux-en-Y bypass frequently averages 75 percent of excess weight. However, as in the case of gastric banding, weight loss among stomach bypass patients is not uniformly sustained in the long term. The majority of clinical reports show that, following bypass weight loss surgery, most patients lose weight very fast and continue to do so up to two years afterwards. Studies into long term weight loss tend to vary, although gastric bypass remains the most effective operation for long term obesity reduction.. Even so, at least 1 in 4 of bypass surgeries fail. Patients either fail to reach their target weight or regain pounds by deliberately ingesting high-calorie foods and gradually stretch the stomach pouch far beyond its original size.
University of Minnesota Review Of Weight Loss Surgery Results (2003)
A review of 136 studies (published 1990-2003) involving 22,094 patients who underwent obesity surgery, conducted by researchers at the University of Minnesota, examined the impact of bariatric surgery on weight reduction. Bariatric procedures included: gastroplasty, adjustable gastric banding and gastric bypass. The average patient-age was 39 years, average pre-operative BMI was 46.9. Just under threequarters of patients were women.
The review found that the average percentage of initial excess weight loss was as follows:
- All patients – 61.2 percent of excess weight
- Gastroplasty – 68.2 percent
- Gastric Band – 47.5 percent
- Gastric bypass – 70.1 percent
University of Washington Study Into Success Of Weight Loss Surgery (2004)
In a review of the health records of 66,109 obese patients in Washington state, 3,328 of whom had undergone a gastric-bypass operation, researchers found:
- One in 50 surgery patients died within 30 days.
- About 3 percent of gastric-bypass patients (under 40 years old) had died in the 13 years after surgery, compared with 13 percent of those who did not have the surgery.
- 12 percent of gastric-bypass patients (all ages) had died after 15 years, compared with 16 percent who did not have surgery.
McGill University Study Into Success Of Weight Loss Surgery (2004)
This study compared 1,035 morbidly obese patients who had gastric reduction surgery (mostly stomach bypass), with 5,746 patients of similar weight who were not operated on. The study found:
- The gastric-bypass patients lost 67 percent of their excess weight.
- In the five-year follow-up period, six people died who had the surgery (four because of the operation), compared with 350 in the larger group.
- The bariatric patients had an 89 percent reduced risk of premature death.
Results Of Other Studies Into The Success Of Weight Loss Surgery
- Patients who have a higher pre-operative body mass index (BMI) tend to lose more total weight. Patients with lower pre-op body mass index lose a higher percentage of their excess weight and are more likely to approach their ideal body weight.
- Type 2 diabetics who have bariatric surgery tend to show less overall excess weight loss than non-diabetic patients.
- A 2000 study of 500 patients showed that 96 percent of associated health conditions – including, hypertension, type 2 diabetes, back pain, sleep apnea, and depression – were improved or cured.
Bariatric Surgery Results
Weight loss surgery reduces obesity, although obese patients are always advised that any gastrointestinal surgery must be accompanied by lifestyle changes in the form of diet modification and increased physical exercise. A patient’s commitment to improving their eating habits, taking regular physical exercise and making other weight-related behavioral changes, is an essential element for the long term success of any obesity operation.