Obesity is defined as a chronic and multifactorial disease, in which there is an increase in the proportion of fat, with consequent metabolic, biomechanical, and psychological dysfunction. The World Health Organization (WHO) recommends the calculation of the Body Mass Index (BMI) for the diagnosis of overweight and obesity, which are defined as a value >25 kg/m2, and > 30 kg/m2, respectively.
Obesity is considered a pandemic. Nowadays there are more than 1,900 million people overweight and it is estimated that more than 650 million people of these are obese. Just in Mexico and in the US, more than 75% of the adult population has obesity, being a serious public health issue. More than 40% of adult women have obesity, whereas near to 30% of men have it.
It is now widely recognized that the treatment and management of obesity requires a comprehensive and multidisciplinary approach, including the prevention and/or treatment of related comorbidities, such as Type 2 Diabetes (T2D), hyperlipidemia (high blood cholesterol levels), high blood pressure, cardiovascular diseases, and Obstructive Sleep Apnea Syndrome (OSAS). Due to this, proper management by an endocrinologist, internal medicine MD, psychologist or psychiatrist, sports medicine expert, a registered dietitian, and a wide experienced surgeon is needed.
The medical and nutritional treatment of obesity is based on changes in diet, increased physical activity, and in selected patients, some medications can be used.
The goal of this treatment is to achieve a total weight loss between 5% and 10% in 6 months. With this, we can expect a reduction in cardiovascular risk and the proper management of several comorbidities. It is important to highlight that the appropriate rate of weight loss is near to 1 kg (2.2 pounds) per week.
Indications for Bariatric Surgery
- Type 2 Diabetes (T2D)
- High Blood Pressure
- Cardiovascular diseases
- Peripheral Venous/Arterial Disease (Varicose veins)
- Obstructive-Sleep Apnea Syndrome (OSAS)
- Obesity Hypoventilation Syndrome
- Hyperlipidemia (High blood cholesterol or triglycerides levels)
- Non-alcoholic Steatohepatitis (Fatty Liver Disease)
- Gastroesophageal Reflux Disease (GERD)
- Lumbar Disc Herniation
- Joint pain (Knee)
- Polycystic Ovary Syndrome (PCOS)
- Urinary incontinence
- Severe limitation of daily activity
- Significant social limitation
Commonly Bariatric Surgery generates a weight loss greater than 30% of total body weight, which means that in most cases, the patients will lose up to 80% to 90% of the excess of weight. The latter is defined as the excess of weight over the upper limit for a healthy weight, which is equivalent to a Body Mass Index < 25 kg/m2. However, the goal after bariatric surgery is to lose at least 50% of this excess of weight.
An example, a patient which his height is 1.70 m (5´7”) should have a weight of 72.2 kg (159 pounds) or even lower. Therefore, a person with the same height and a weight of 101 kg (222.7 pounds) who is a candidate for Bariatric Surgery, has an excess of weight near 30 kg (66.2 pounds). The goal in this patient, following bariatric surgery, will be a weight lower than 85 kg (187 pounds), the equivalent to losing at least 50% of the excess of weight.
Regarding the impact of Bariatric Surgery on related comorbidities or diseases, it has been described that more than 70% of patients with type 2 diabetes will achieve complete remission during the first year, and up to 40% will remain in complete remission at 5 years. Some related factors to better outcomes in terms of type 2 diabetes are early surgical treatment (within the first 2 years of diagnosis), younger age, lower number of medications, and absence of insulin use. Therefore, the earlier the surgery, the better results the patient will have.
In terms of high blood pressure, two-thirds of patients will experience partial or complete remission. Meanwhile, for hyperlipidemia and OSA, bariatric surgery is very effective, as more than 80% will have complete remission during the first year and this persists for the coming years.
Bariatric procedures are classified regarding their main mechanism, whether it is a restriction of food intake (restrictive), malabsorption of nutrients (malabsorptive), or those who are a combination of both (mixed). Among the restrictive procedures, there is the Sleeve Gastrectomy and the Laparoscopic Adjustable Gastric Band (LAGB), whereas Biliopancreatic Diversion with Duodenal Switch and the SADI-S are classified as malabsorptive procedures. Roux-en-Y Gastric Bypass (RYGB) and Mini-Gastric Bypass are considered as mixed procedures.
By a board-certified bariatric surgeon. For free