Are you thinking about having weight loss surgery or just interested in learning more about it? Read this article to find out all about the various procedures, associated risks, possible benefits, and who qualifies.

Affecting more than a third of the adult U.S. population, obesity has become an alarming pandemic with severe health consequences. Numerous studies have demonstrated a clear link between obesity and debilitating conditions including type 2 diabetes, hypertension, stroke, coronary heart disease, osteoarthritis, and even certain cancers. According to the CDC, in 2008 medical costs associated with obesity were estimated to be an astounding $147 billion [1].

It is no surprise then that study after study has found weight loss to be associated with improved quality of life and reduction in morbidity. Of the possible weight loss solutions, bariatric surgery – a procedure that alters the digestive system’s anatomy to promote weight loss – is the most helpful intervention providing sustained results as compared to lifestyle modifications and pharmaceuticals [2]. All overweight individuals, however, should not resort to bariatric surgery. Rather, those who meet certain criteria (which will be discussed later in the article) and have consulted with a physician are most likely to benefit from the procedure.

Types of Surgeries

With obesity levels on the rise and advances in laparoscopic surgery (a minimally invasive technique that relies on small incisions and has a faster recovery time) it is no surprise that more than 200,000 bariatric surgeries were performed last year alone [3]. The four most commonly performed bariatric procedures in the U.S. fall into two categories based on their mechanism of action: restrictive or a combination of malabsorptive and restrictive. Restrictive procedures function by physically reducing the size of the stomach in order to produce earlier satiety and limit the intake of food. Combinations procedures, on the other hand, use restrictive techniques but also involve removing portions of the digestive tract, making it more difficult to absorb digested food components.

Restrictive Procedures

Adjustable Gastric Banding (AGB), which is commonly referred to as a “lap band” involves placing an inflatable silicon band around the top of the stomach in order to divide it into two smaller sections. The smaller upper section, which slowly drains into the lower section, fills with less food and provides satiety with a smaller meal. Gastric banding, a relatively safe and simple procedure, is performed laparoscopically with a minimal incision and can also be reversed, contributing to its increasing popularity amongst patients and practitioners.

Sleeve Gastrectomy is also a laparoscopic procedure and involves removing nearly 75 percent of the stomach, resulting in a narrow tube or sleeve for the stomach. This irreversible procedure can be used as a precursor surgery to gastric bypass. Because of the more extensive decrease in stomach size, this intervention tends to provide more significant weight loss than AGB.

Combination Restrictive/ Malabsorptive Procedures

Roux-en-Y Gastric Bypass (RYGB), commonly referred to as gastric bypass, has been the most commonly performed bariatric surgery in the U.S., accounting for nearly 80 percent of the annual total [4]. Performed laparoscopically or as an open surgery, RYGB initially involves dividing the stomach into a small top pouch that is sealed off from the lower section. This upper pouch is then directly connected to the distal small intestine enabling food to bypass a portion of the stomach and small intestines.  RYGB is generally regarded as having rapid as well as sustained weight loss [4,5].

Bilopancreatic Diversion with a Duodenal Switch (BPD-DS) is similar to the RYGB in that the surgically smaller stomach is attached to the distal small intestines. With BPD-DS, the proximal small intestine that was separated from the stomach is also reattached prior to the colon. Keeping this portion provides more normal absorption of nutrients as compared to gastric bypass alone [4,5].

Who Qualifies

Bariatric surgery should not be considered as a first line therapy for weight loss; in fact, study-supported general guidelines exist to better screen adults for such procedures. Firstly, weight loss surgeries should be considered only after extensive diet and exercise regimens have failed. Adult patients with a body mass index (BMI) of more than 40 (morbidly obese) qualify, and those with a BMI greater than 35 (obese) are considered only if they also have a comorbidity such as hypertension, type 2 diabetes, sleep apnea, or severe musculoskeletal problems. These procedures are not commonly performed in people over the age of 65 due to the increased risk of severe complications. All patients should be well informed on bariatric procedures ahead of time and will be evaluated by multiple healthcare providers regarding various organ system functions, weight history, and psychological status. This is not only critical in assessing the operative risk, but also in determining if surgery is the best option for a patient. Ultimately, one should consult with a physician to fully understand the individual risks and benefits involved [6,7]. The guidelines for children under the age of 18 are similar to those of adults, yet bariatric procedures in these patients remain more controversial. Discussing with a health care provider is again important in assessing the risks and possible benefits for a particular adolescent [8].

Possible Benefits

Bariatric surgery should not be thought of as a cure to being obese, but rather as a component of a comprehensive weight loss strategy. Maintaining high calorie diets and low activity lifestyles have led many patients to regain their initial weight loss and therefore experience little to no health benefits post-surgically [5].  To really benefit from such a procedure requires a patient’s commitment to alterations in diet and exercise habits. The outcomes of bariatric surgery are extensive and numerous studies have demonstrated that on average, patients lost between 50 and 70 percent of their excess body weight [9]. This drastic reduction in weight loss has profound effects on reducing the risk of comorbidities with one study demonstrating an 89 percent reduction in the risk of mortality [10]. In 2009, research by Buchwald et al. found that 78 percent of individuals with type 2 diabetes had complete resolution of their clinical symptoms following the weight loss surgery [11]. Similarly, studies have shown significant decreases in hypertension, high cholesterol, heart failure, sleep apnea, joint pain, and psychological disorders with significant weight loss post-surgically [10]. A study performed at Duke University Medical Center considered many factors including these comorbidities to gauge health-related quality of life (HRQOL) for patients six years after bariatric surgery. Compared to their non-surgical counterparts, patients having bariatric procedures demonstrated significantly improved and stable HRQOL [12].

Risks

Like any invasive procedure, bariatric surgery comes with the risk of complications and long-term consequences. The immediate surgical risks include bleeding, infection, hernias through the incision, and an adverse reaction to anesthesia. There is also the post-surgical chance of clot formation or bowel obstruction due to scar tissue development. A recent study estimated the 30-day risk of mortality due to these early complications to be approximately 0.3% [13].  Each of the bariatric procedures previously discussed possesses unique risks, which may factor into the particular surgery chosen for an individual. With RYGB comes the serious risk of stomach or intestinal fluid leakage that can lead to severe infection and may require additional surgery. Because bariatric surgeries rely on food restriction or malabsorbtion, there is a significant potential for nutritional deficiency. Nutrient and vitamin supplementation is therefore common and will vary depending on the specific procedure performed. The rapid weight loss from these surgeries increases the risk of gallstone development in some patients, but this can be prevented through certain medications. Finally, more common and less severe risks include vomiting, cramps, diarrhea, and ulcer formation. Many other factors including comorbidities and age can drastically alter the potential for serious complications. Therefore, it is critical for a patient to consult with a health care provider in determining if bariatric surgery is a viable option and if so, which specific procedure has the greatest benefit to risk ratio [14].

Works Cited

1. “Adult Obesity.” CDC.gov. CDC, 27 Feb. 2012. Web. 10 Mar. 2012.http://www.cdc.gov/obesity/data/adult.html.
2. PMID: 21727936
3.  ”Roux-en-Y Gastric Bypass Surgery.” MUSC Health. Medical University of South Carolina. Web. 10 Mar. 2012. http://www.muschealth.com/weightlosssurgery/procedures/bypass.htm.
4. “Types of Weight Loss Surgery.” Weight Loss Surgery Health Center. WebMD, 30 Aug. 2009. Web. 10 Mar. 2012. http://www.webmd.com/diet/weight-loss-surgery/your-options-in-weight-loss-surgery-making-the-choice.
5. “Bariatric Surgery for Severe Obesity.” Weight Control Information Network. National Institute of Diabetes And Digestive & Kidney Disease. Web. 10 Mar. 2012.http://win.niddk.nih.gov/publications/gastric.htm.
6. PMID: 20810234
7. “Gastric Bypass Surgery.” Mayo Foundation for Medical Education and Research. Mayo Clinic, 11 Oct. 2011. Web. 10 Mar. 2012. http://www.mayoclinic.com/health/gastric-bypass/MY00825.
8. PMID: 21804384
9. PMID: 22054156 
10. PMID: 22054155
11. PMID: 19272486
12. PMID: 22386053
13. PMID: 22265094
14. “Exploring the Benefits and Risks of Bariatric Surgery.” Johns Hopkins Center for Bariatric Surgery. Web. 10 Mar. 2012. http://www.hopkinsbayview.org/bariatrics/surgery/risksandbenefits.html.