The disease called Morbid Obesity has been declared an epidemic in many countries like the US, UK and Australia. Numerous options like dieting, exercise and other lifestyle modifications, with and without medications, are being continuously tried, so far with dismal results, especially in maintaining that ideal weight. This is the greatest challenge faced today.
According to a report published in 2014 by the Lancet medical journal, the worldwide proportion of overweight adults with a Body Mass Index (BMI) of 25 kg/m2 or greater increased between 1980 and 2013 from: 28.8% to 37% in men and 29.8% to 38% in women.
In Indians, the prevalence of obesity increased from 16% in 2007 to 21% in 2014 for women, 12% in 2007 to 19.5% in 2014 for men
India ranks third, after USA and China, in the number of obese population.
An obese person runs the risk of developing multiple medical complications like high blood pressure, diabetes, high cholesterol, arthritis and several other conditions. In diabetes, obesity accelerates the onset of heart disease. There is also a strong link between obesity and infertility, especially in women with PCOD (Polycystic Ovarian Disease). Sleep apnea is another potentially lethal disorder which is immensely benefitted by weight loss and bariatric surgery. At present there are about 70 million obese and morbidly obese people in India who require treatment in some form for their obesity and/or associated medical diseases, the commonest being diabetes.
Brief history of Bariatric Surgery
The concept for a surgical treatment of obesity was developed from observing the significant postoperative weight loss developed in patients that had large portions of their stomachs or small intestines removed Victor Henrikson (1952), Varco (1953), Kremen and Linner (1954), Payne (1963) Sherman (1965). This led to the development of different bariatric surgery procedures that can be categorized into three approaches including restrictive, E Mason (1971), M Long (1978), Paul (1979), Wilkinson (1980), Kuzmac (1986), Marceau (1993) and combined mal-absorptive and restrictive, Mason (1966), Griffen (1977), Torres (1983), Fobi (1988) & solely malabsorptive procedures (Scopinaro (1976), Hess & Hess (1986) .
Since the end of the 1980s, laparoscopic techniques have revolutionized general surgery. Though in the beginning bariatric surgeons were reluctant to perform laparoscopic bariatric surgery, introduction of gastric bands made it easier to adapt this approach. International pioneers in this field were M Belachew (Belgium) and P Forsell (Sweden) (1991). Subsequently Wittgrove (1993) performed RYGB laparoscopically. By the end of year 2000, laparoscopic bariatric surgery was well established and proved to be better for early post op recovery.
The current guidelines for patient selection are: BMI of 35 and above without any other medical diseases, and BMI of 32 and above for patients with associated medical conditions that will be significantly benefitted by bariatric surgery for eg. Adult onset diabetes mellitus (T2DM). In both classes of patients, each patient must be thoroughly evaluated by a multidisciplinary team to determine whether surgery is the best or only option for him/her. Each patient must also have psychological counselling, and undergo a trial of lifestyle modification, diet and medication if necessary, to lose as much weight as possible prior to surgery. For a period of 7-14 days before surgery many patients will be placed on a Very Low Calorie Diet (VLCD) mainly to reduce the weight of the liver which helps during the operation. An absolute contraindication to surgery is severe psychiatric disorders.
An important point to stress is that majority of patients selected for surgery have had one or multiple failures of lifestyle modification including various diet and exercise regimes.
Currently, the options can be broadly divided into non-operative and operative, with the operations being classified as essentially restrictive or metabolic. Every bariatric procedure has metabolic effects to a lesser or greater degree depending on the type of procedure.
The following chart shows how bariatric surgery has grown in the last decade:
The commonest non-operative intervention is Endoscopic insertion of a gastric balloon. The balloon is distended with approx. 500 ml of saline and placed in the upper part of the stomach as shown in fig1.
Fig1. Endoscopic gastric balloon placement
The balloon works by an entirely mechanical effect of continuously stretching the fundus of the stomach thus decreasing hunger and causing early satiety after eating. It can be kept inside for 6-12 months, after which it has to be removed. It is expected that the patient will find it much easier to adapt to lifestyle changes and maintain the weight loss achieved. Typically a weight loss of approx. 25 kg can be expected.
Let’s take the example of Payal Shah, a young unmarried female, weighing 90 kg., who had tried numerous weight loss measures but failed to maintain it, and was prepared to continue with dietary restriction and increased physical activity, after removal of the balloon, underwent the procedure 3 months ago. She now weighs 79 kg and is certain she can shed much more due to the reduced hunger and food intake. The picture shows her before and after the balloon placement.
All operations are done laparoscopically and the hospital stay is 2-5 days. By far the commonest procedure done, not only in India but across the globe is the Sleeve gastrectomy. In this procedure, the stomach is reduced to about 25% of its original size and leaving a small portion that looks like a sleeve or banana.
The following figure is a diagrammatic representation of the gastric sleeve after surgery.
Take the example of Mr. Jadhav, a middle aged male who was suffering from severe sleep apnea due to snoring, with his oxygen levels falling to dangerously low levels during his sleep. He also had diabetes, asthma and joint pains. His weight was 103 kg prior to a sleeve gastrectomy in April, this year, and he was using a CPAP machine at night to treat his sleep apnea.
Post surgery, he has had complete resolution of diabetes and his sleep apnea. His weight is now 87 kg, and he only uses the CPAP machine if he has an attack of asthma, which according to him is very rare.
The following pictures show him before and after surgery.
Following any bariatric procedure, the long-term possibilities of weight regain and nutritional deficiencies are paramount, requiring a high degree of patient compliance and follow-up visits for clinical and lab tests to look for protein and vitamin deficiencies. A sleeve gastrectomy has the least nutritional deficiencies among all the bariatric procedures, but some weight regain after 3-5 years is a possibility due to dilatation of the gastric sleeve.
Mr. Desai, a middle-aged gentleman was suffering from sleep apnea but was unable to tolerate the CPAP machine as it didn’t allow him to sleep at night due to severe discomfort. He approached me pleading for a solution as his condition was affecting his work, as he would often fall asleep during the day. He weighed 111 kg prior to surgery, and underwent a sleeve gastrectomy in May, this year. His weight is now 92 kg and he doesn’t require a machine at night. He also hasn’t had any sleeping spells during the day, since soon after the surgery.
The Roux-en-Y Gastric Bypass (RYGB)
This is a combined restrictive and malabsorptive procedure and till recently, was the commonest bariatric procedure performed in the US. It has now been replaced by the sleeve gastrectomy, and over 50% of all bariatric procedures in the US are now sleeve gastrectomies.
The next figure shows a typical RYGB procedure in which a small gastric pouch forms the restrictive element and bypassing approx. 100 cm of the proximal small bowel forms the metabolic element, by malabsorption of ingested food. This is a relatively more complex operation with more post-op complications, but gives the best long-term results in weight and diabetes control.
Mini Gastric Bypass/One Anastomosis Gastric Bypass:
Among all the commonly performed surgeries this gives the maximum malabsorptive or metabolic effect with the advantage of a larger gastric pouch, allowing more food intake than the conventional R-Y gastric bypass. In this procedure although a gastric tube is created to give the restrictive element, the remainder stomach remnant is left in the abdomen, similar to the conventional gastric bypass. But unlike the conventional bypass procedure which requires creation of two anastomoses, the MGB requires only one anastomoses, making it technically easier to perform while giving results similar to the conventional bypass, with less post-operative complications. While this procedure has yet to be formally accepted in the US, it is widely performed in the rest of the world, with India being a leading country.
With both the bypass procedures, long-term nutritional deficiencies are very common and strict follow-up protocols are needed.
The other less commonly performed procedures include:
- Gastric Banding
- Duodenal Switch
- The Battle against the Bulge is being fought since quite a while, with dismal results. Surgery for obesity and related Metabolic problems has been a game changer with excellent results esp. in patients who have given up the fight.
- We see early resolution of obesity and comorbidities but only 2% of all morbidly obese patients are referred for surgery.
- Bariatric Surgery is the only effective and enduring weight loss therapy in the morbidly obese.
- Surgery results in greater improvement in weight loss outcomes and weight associated comorbidities compared with non-surgical interventions, regardless of the type of procedures used.
- When compared with each other, certain procedures resulted in greater weight loss and improvements in comorbidities than others. Outcomes were similar between RYGB and sleeve gastrectomy, and both of these procedures had better outcomes than adjustable gastric banding.
- For people with very high BMI, biliopancreatic diversion with duodenal switch resulted in greater weight loss than RYGB.
- Duodenojejunal bypass with sleeve gastrectomy and laparoscopic RYGB had similar outcomes.
- Isolated sleeve gastrectomy led to better weight-loss outcomes than adjustable gastric banding after three years follow-up