OBESITY & METABOLIC SYNDROME
India has now the world's third largest number of obese individuals following USA and China. We have 20% of our population classified as obese, 40% as malnourished and 40% normal weight. Our diabetic population is world's highest and there is correlation between diabetes, metabolic syndrome and obesity. India has already been labeled as the Diabetes capital of the world with nearly 80 million diabetics.
DEFINITIONS AND RISK FACTORS
Body mass index (BMI) is used to define obesity. If your weight for instance is 80 kg and height is 5 feet 7 inches (1.70 m ), then your BMI would be 80/2.89 = 27.68 kg per m2
■ In adults, obesity is defined as a BMI of 27.5 kg/m2 or greater.
■ Adult obesity is further categorized as class I, BMI of 27.5 to 32.5; class II, BMI of 32.5 to 37.5; and class III (also known as morbid obesity), BMI of 37.5 or greater.
■ In children, obesity is defined as weight exceeding the 95th percentile on standard growth charts.
Other risk factor very specific to India is what is known as Metabolic Syndrome which includes abdominal obesity, high cholesterol, blood pressure or blood sugar levels. This puts individual at tremendous risk for systemic diseases involving the heart, brain, liver and kidneys.
Obese patients may experience a 12-fold reduction in life expectancy compared with age-matched control subjects.
CAUSES OF OBESITY
It is wrong to say that obesity is just a simple result of overeating. A number of factors have been found to affect weight regulation, including genes and their epigenetic modifications; maternal weight during pregnancy; metabolic imbalances; and environmental factors, including food intake, movement and physical activity, sleep, psychosocial stress, toxin exposure, and microbiome composition.
EFFECTS OF MORBID OBESITY
The high prevalence of obesity is of concern from several perspectives. Being obese increases the risk for developing chronic disorders such as heart disease, stroke, hypertension, type 2 diabetes, liver disease, joint problems, sleep disturbances, and some cancers, which in turn impairs an individual’s quality of life.
You may not be able to get around or to perform normal daily activities. You may avoid public places. You may even encounter discrimination.
NON-SURGICAL TREATMENT OF OBESITY
These include caloric restriction, exercise, behavior modification, and drug therapy. This is the preferred method for people with BMI less than 32.5
The long-term results of caloric restriction programs are good for the overweight but have been poor for those who are over a BMI of 32.5 and are morbidly obese. A regular balanced diet that is sustainable in the long term is what works best. Most diets concentrate on high proteins and low carbohydrates. Crash diets causes nutritional imbalance and usually ends with weight regain that may be higher than the start point.
Exercise programs again are good for the overweight with some type of caloric restriction. Also it is important to keep a balance of both aerobic and anaerobic exercises to ensure fat loss without loss of muscle mass.
Pharmacologic programs are popular, but they are equally ineffective as a treatment for morbid obesity; they use appetite-suppressing medications that act by increasing the central nervous system concentration of serotonin, a mood-elevating neurotransmitter believed to be involved in eating disorders. 10% weight loss is seen but is regained once the medicine is stopped.
CURRENT SURGICAL THERAPIES FOR MORBID OBESITY
Surgical approach is by 3 methods:
- Open surgery ( not done any more ),
- Laparoscopic Surgery ( most centers ) and by
- Robotic Surgery ( selected centers )
1. Restrictive procedures (surgical reduction of the stomach size to reduce amount of food intake)
- Adjustable Gastric Banding - POPULAR FOR SELECTED CASES
- Sleeve Resection - POPULAR
2. Combined restrictive and malabsorbtive ( size reduction with bypass )
- Roux en Y Gastric Bypass (RYGB) -POPULAR
- Single Anastomosis Bypass ( MGB - 'mini' gastric bypass )- POPULAR
3. Other Procedures
- Endo luminal sleeve - UNDER EVALUATION
- Gastric Pacemakers - UNDER EVALUATION
- Gastric Balloon - TEMPORARY MEASURE
∙ Patients with a BMI more than 40 kg per m2 ( 37.5 in India and Asia ) and those with BMI more than 35 ( 32.5 in India and Asia ) with medical diseases are potential candidates for surgical treatment of morbid obesity after failure of conservative treatment.
∙ Surgery should be offered only to patients who are well informed and motivated and who are acceptable surgical risks; a multidisciplinary team of nutritionists, nurse clinicians, internists, psychologists or psychiatrists, and surgeons should evaluate the patients preoperatively.
Gastric Banding is a popular restrictive procedure currently. A band is placed around the upper most part of the stomach. This band divides the stomach into two portions, one small and one larger portion. Because food is regulated, most patients feel full faster.
The Gastric Sleeve Resection removes a great part of the stomach and leads to loss of weight. Mechanism is by a reduction of food intake and also changes in gut hormones. This is useful in those with a BMI between 35 and 45.
COMBINED RESTRICTIVE AND MALABSORBTIVE
The Roux en Y Gastric Bypass
This is the gold standard bariatric surgery with best long-term time tested results. By adding malabsorption, food is delayed in mixing with bile and pancreatic juices that aid in the absorption of nutrients. The result is an early sense of fullness, combined with a sense of satisfaction that reduces the desire to eat. In this procedure, stapling creates a small stomach pouch. The outlet from this newly formed pouch empties directly into the lower portion of the jejunum, thus bypassing calorie absorption. Also leads to resolution of diabetes and metabolic syndrome, acid reflux etc.
The Single Anastomosis Gastric Bypass ( popularly known as 'mini' gastric bypass or MGB ) uses a long stomach sleeve tube that is connected to small intestine at a length between 150 and 250 cm based on original weight, eating patterns, presence of diabetes, metabolic disorders etc. The Mini-Gastric Bypass, which uses the loop reconstruction, has been suggested as an alternative to the Roux en-Y procedure.
ROBOTIC vs LAPAROSCOPIC BARIATRIC SURGERY
Laparoscopic bariatric surgery has replaced open surgery in most abdominal operations including bariatric surgery. Of late, Robotic surgery has gained popularity due to the added advantages of 3D vision, precise and accurate tremor free instrument movements and lack of surgeon fatigue while suturing and dealing with heavy abdominal wall in patients of morbid obesity. This technology is however available in limited hospitals across the world due to the capital expense in setting it up.
WHICH IS THE BEST LAPAROSCOPIC BARIATRIC SURGERY ( MINIMAL ACCESS / ROBOTIC SURGERY FOR OBESITY ) ??
There is no best surgery. Had there been a best surgery, the others would not have existed.
So how do we decide ?
Well this is done on the following basis
- BMI of patient, current weight and target weight
- Presence of other problems like Diabetes, Gastroesophageal reflux etc
- Dietary habits of the person
- Physical activity and motivation for exercise on a long term basis
- Experience of the surgeon for a particular procedure