The number of obese people is increasing dramatically worldwide. One can even say that the disease is spreading like an epidemic or even pandemic. According to the current WHO data, approximately 21.3% of German citizens are obese, i.e. they have a BMI of more than 30 kg/m².
BMI of 35 kg/m² is considered the Obesity Grade II, BMI of more than 40 kg/m² is the Obesity Grade III. The health implications are dramatic: obesity causes numerous secondary diseases, most importantly diabetes mellitus and cardiovascular diseases. Besides different types of cancer are more common in obese people than in people with normal weight.
In addition, higher health costs and sick leaves greatly impacts the person economically.
Because of morbid obesity individuals usually experience a significant reduction of quality of life, they also are often confronted with social exclusion and prejudice. Surely every obese person has heard the well-intentioned advice: "Eat less and move more", even though this advice certainly is a good way to prevent obesity, it does not provide an effective therapy. Overweight patients who in addition to exertional dyspnea also have severe joint pain or degeneration, will only be able to follow this recommendation partially.
At the same time, modern people are moving less, hard physical work has become much rarer, cheap high energy food is everywhere and is aggressively advertised. All these factors have contributed to the sudden increase in obesity, seen since the 1970s in almost all industrial and newly industrializing countries.
Since conservative therapy has a rather low efficacy and therefore cannot solve the problem for the majority of patients, surgical procedures have been developed that can alter the anatomy and physiology of food intake to make the rapid and sustainable weight loss possible.
The United States of America is obviously ahead of Germany in the development of obesity. The number of surgical interventions to treat morbid obesity have increased in such a way that they have already overtaken the two most frequent interventions: gallbladder removal and hernia operation. These interventions are being carried out more and more often in Europe, too.
An operative reduction of pathological excess weight always represents a considerable intervention in the body anatomy and physiology and sometimes has a critical influence on food digestion and metabolism. In addition, there are always risks associated with a major surgical procedure. Therefore, a surgical treatment should never be the first option, it can be chosen only if all other therapy methods have failed or promise no success.
At present, the operations are not reimbursed by health insurance companies by default, each intervention must be applied for and motivated individually. A health insurance company will take over the costs of such an op taking into account not only medical criteria of its usefulness: one should also comply with further conditions. The following criteria should be met:
- Patients should be between 18 and 65 years old.
- Their BMI should be greater than 40 kg/m² or if the BMI is over 35 and patients suffer from health problems that are associated with severe excess weight, e.g. diabetes, joint diseases, heart problems or snoring with regular suspending of respiration (sleep apnea).
- The patient has been overweight for more than 5 years.
- A multimodal conservative therapy has been conducted for more than 6 months and had no effect.
- Patients have no other diseases that could cause the overweight.
- Sufficient compliance.
- No excessive consumption of alcohol or drug abuse.
A conservative therapy attempt is considered sufficient if the treatment concept has elements from the three key pillars: movement, nutrition and behavior. The therapeutic approaches from these sub-areas must be coordinated and carried out simultaneously. Medications can be used to support them.
There are two types of surgical procedures used in the obesity surgery, also known as bariatric surgery: restrictive and malabsorptive as well as the combination of both.
The aim of these procedure is to reduce the amount of food that can be eaten at once. This way the patient starts feeling full faster and the sensation stays for a longer time. The classic example of such operation method is the Swedish adjustable gastric banding (SAGB).
A minimally invasive operation (laparoscopy) is used to place an adjustable gastric banding around the upper part of the stomach. It can be filled from the outside through a port chamber with liquid thus narrowing it. Larger food portions can cause vomiting or esophagus stretching. If this happens too often, the banding becomes ineffective.
The gastric banding is a foreign body, but it is usually well tolerated. In principle, the banding can remain in the body for a lifetime – even when the desired weight has been reached. If it gets removed, the patient usually regains weight.
Restrictive procedures, such as the gastric banding, demand the collaboration and cooperation of the patient in order for the therapy to be successful.
In case of sleeve gastrectomy or left lateral stomach resection a large part of the stomach is surgically removed from the body. Thus, a gastric tube is formed which can hold much smaller amount of food than before.
Its function is primarily restrictive, similar to the gastric banding. However, an additional effect of the "sleeve" is that the part of the stomach is resected, which produces certain hormones responsible for the sensations of hunger and satiety. This includes, for example, the ghrelin.
Thus, the sleeve gastrectomy not only limits the amount of food the stomach can hold, it also changes the hunger, saturation and taste sensations, resulting in a reliable weight loss.
These procedures are aimed to alter the digestive physiology in such a way that only part of the consumed food is absorbed by the body. This naturally reduces the amount of calories ingested. However, this procedure also has disadvantages: in the same way severe vitamin deficiency symptoms can occur as well as steatorrhea and extreme flatulence. The classical representative of such surgeries is the biliopancreatic diversion (BPD), which belongs to exceptional indications.
Gastric bypass is a classic example of the combined type of procedures. A small part of the stomach, a so-called pouch is surgically separated from the rest of the stomach, still remaining in the body. A part of the small intestine is anastomosed to the upper stomach, so that the duodenum and the proximal part of the jejunum are excluded from of the food passage and the alimentary limb is separated from the biliopancreatic limb.
Only much later in the Roux-en-Y jejunum anastomosis the digestive enzymes meet the food bolus. Only from here the digestion takes place as usual. Since the alimentary limb, i.e. the part through which the food gets transported without digestive enzymes, is approximately 150 cm long, the surgery was considered to cause a certain malabsorption. However, this fact is now disputed, at least with this length of the digestive limb.
After a gastric bypass operation, the patients first feels no or much less hunger, the sense of taste and smell changes and they lose weight very rapidly. However, this cannot be explained by restriction or malabsorption alone. Surprisingly, the total energy consumption of the body increases after the operation despite significantly reduced calorie intake. In contrast, a diet with reduced energy consumption automatically lowers the basal metabolic rate, which makes further weight loss more difficult and when the diet is over leads to a rapid weight regain.
Diabetes mellitus is also dramatically affected. Probably due to the exclusion of duodenum and the early contact of food with the distal jejunum, there is a series of humoral changes that can break the extreme insulin resistance. Many patients who required high doses of insulin before the surgery are able to significantly reduce or even eliminate its intake altogether.
This effect is so great that it is now debated whether to operate patients with normal weight or only slightly obese diabetics if the diabetes can no longer be controlled in a conventional way. This metabolic surgery will probably prevail even more in the future, even if the mechanisms behind the effects are not fully understood at the moment.
Nowadays all bariatric surgeries can be carried out minimally invasive with tolerable risk, but they should be performed in an interdisciplinary centre in which all the disciplines involved in conservative therapy, diagnostics, preparation and implementation of the operation and, above all, the life-long aftercare of the patients work together. In order to prevent deficiency symptoms, patients must also take vitamins and micronutrients for their whole life after the gastric bypass operation, as they are absorbed in the proximal gastrointestinal tract. Diagnostics and treatment of other complications requires a lot of experience and expertise.
In 2009 the German Society for General and Surgery therefore drafted special guidelines, that allow clinics to get certified as obesity centres. In addition to certain infrastructural requirements, an obesity-experienced surgeon team and a minimum number of performed bariatric interventions are required.
Although these operations are very popular and the results in many cases is stunning, yet the gastric bypass and other obesity surgeries are not miracle remedies. If the doctors believe you are a good candidate for the procedure, they will surely explain to you that the operation alone does not guarantee that you will be able overcome obesity or maintain a healthy weight for a long time. In order to achieve tangible and lasting effects, it is necessary to maintain a strict dietary plan and do exercises. A scalpel can do nothing to improve your commitment and willpower.