Severe obesity, sometimes known as “morbid obesity ”, is commonly defined as being 100% above ideal body weight. Body Mass Index or BMI is calculated based upon a person’s height and weight, and is more accurate to determine obesity.
The rates of obesity have been increasing steadily with a prevalence of approximately 25% in most developed countries. Even in India, it is estimated that upto 30% of school children in the metro cities are over weight. The World Health Organization (WHO) in 1997 declared obesity as a major public health problem and a global epidemic. In general, a body mass index of 25 kg/m2 or greater is considered overweight and 30 kg/m2 or greater is considered obese. According to the estimates by WHO, more than 1.9 billion adults aged 18 years and older are overweight, and of those, over 650 million adults are obese.
Obesity is associated with the development of life-threatening complications such as hypertension, diabetes, sleep apnea, and coronary artery disease, to name a few.
Numerous treatment approaches have been advocated, including low calorie diets, medication, behavioral modification and exercise. However, the only treatment proven to be effective in long-term management of severe or morbid obesity is bariatric surgery.
What Causes Severe Obesity?
The cause of severe obesity is is not fully understood and there are probably many factors involved. In obese persons, the set point of stored energy is too high. This altered set point may result from a low metabolism with low energy expenditure, excessive caloric intake, or both. There is scientific data that suggests obesity may be inherited.
Severe obesity is most likely a result of a combination of genetic, psychosocial, environmental, social and cultural influences that interact resulting in the complex disorder of both appetite regulation and energy metabolism. It is not a simple lack of self-control by the patient.
What are the Treatment Options?
In 1991, the National Institutes of Health (USA) concluded that non-surgical methods of weight loss for patients with severe obesity are not effective over long periods of time. It was shown that nearly all participants in any non-surgical weight-loss program for severe obesity regained their lost weight within 5 years. Although some medications are available to induce weight loss, there does not appear to be a role for long-term medical therapy in obesity and weight gain is rapid once medication is stopped. Various weight loss programs use behavior modification techniques in conjunction with low calorie diets and increased physical activity, but nearly all the weight loss is regained after 5 years.
Laparoscopic surgery for obesity is for people who are severely overweight (morbid obesity). Laparoscopy involves using a specialized telescope (laparoscope) to view the stomach, and operate using specialized instruments. This typically allows smaller abdominal incisions.
A number of weight loss operations have been devised over the last 40-50 years. They cause restriction of food intake and reduce absorption of calories. The most commonly done surgeries include: Gastric bypass, gastric banding and sleeve gastrectomy.
Laparoscopic sleeve gastrectomy which is the most commonly done operation involves removal of greater part of the stomach. This reduces the stomach volume and absorption. There are also other physiological and hormonal effects which help in reducing weight and resolution of diseases like diabetes etc.
Choosing the operation involves the patient’s age, BMI, associated medical conditions and consideration of diet and eating habits.
The advantages of the Laparoscopic approach include:
Reduced post-operative pain
Shorter hospital stay
Fewer wound complications
Faster return to work
Who Should Be Considered for Bariatric Surgery?
The following guidelines for selecting patients for obesity surgery were established by the National Institute of Health (USA):
Patients with a Body Mass Index (BMI) of ≥ 40 kg/m² or BMI ≥ 35 kg/m² with at least one obesity-related condition (diabetes, hypertension, dyslipidemia, sleep apnea, etc.).
This BMI cutoff is reduced by 2.5 kg/m² in Asian populations. Those below this BMI may also benefit from these operations as a metabolic procedure to treat uncontrolled associated medical problems which include hypertension (high blood pressure), diabetes (too much sugar in the blood), heart disease, breathing problems or lung disease, sleep apnea (snoring), and arthritis, just to name a few.
The patient should have attempted weight reduction using other treatment methods without success. They should have an objectively measurable complication (physical, psychological, social, or economic) that might benefit from weight reduction.
The patient should understand the full importance of the proposed surgical procedure including suspected risks and complications and should be willing to be observed and followed by a medical professional for many years.
What Preparation Is Required?
A thorough medical evaluation along with supplemental diagnostic tests including a nutritional evaluation may be necessary.
A psychiatric or psychological evaluation may be required to determine the patient’s habits and ability to adjust to changes after the operation.
Consultation from specialists, such as a cardiologist, pulmonologist, gastroenterologist or endocrinologist may be needed depending on specific medical conditions. Modifications in the diet, physical activity and medications may be necessary before surgery.
What are the Expected Results after Surgery?
The success rate for weight loss surgery is reported as being good to excellent. Most reports show a 50% or greater excess weight loss after one year. Weight loss generally continues for all the procedures for 18-24 months after surgery. Some weight gain may occur about two to five years after surgery.
Associated medical conditions
Surgery has been reported to improve conditions such as sleep apnea, diabetes, high blood pressure, high cholesterol and even fertility. Many patients report an improvement in mood and other psychosocial aspects including physical activities and self esteem.
What Complications Can Occur?
Although bariatric surgery is considered safe, and while all preventive care is taken, some complications may occur as with any major operation. However, the risk of these complications is low when weighed with the potential health benefits for the patient.
After Bariatric Surgery
After the operation, it is important to follow instructions carefully. Although many people feel better in just a few days, remember that the body needs time to heal and recover. Most patients get back to normal light activities in one to two weeks. A dietician monitored diet, along with supplements if needed, has to be followed for the duration of the treatment. Regular exercise, quitting addictions like smoking, alcohol and junk foods are some of the lifestyle changes that will ensure long term success.
Dr Shafy Ali Khan, the author, is a Consultant and Co-ordinator, General and Minimal Invasive Surgery, at KIMSHealth.