Bariatric Surgery

Bariatric surgery (synonym: bariatric surgery) refers to surgical procedures to control morbid obesity. These are various surgical procedures (see below) that may be offered for obesity with a BMI ≥ 35 kg/m2 or greater with one or more obesity-associated comorbidities when conservative therapy has been exhausted. See below for additional indications. Surgical procedures for the treatment of obesity are intended to reduce the increased risk of metabolic or cardiovascular complications. Surgical procedures for the treatment of obesity can also massively improve the patient’s quality of life.

Obesity

Causes

  • Heredity – a genetic predisposition for the occurrence of obesity could be found. However, the predisposition for the development of obesity is not limited to one gene; it is a polygenic inheritance. However, experimental studies have shown the particular importance of leptin resistance at the obesity receptor in the hypothalamus.
  • Hormonal – a minor epidemiological role is usually played by hormonal causes in obesity. Hypothyroidism (underactive thyroid gland) is associated with weight gain and decreased activity, among other symptoms. Prolonged treatment with cortisone when the Cushing’s threshold is exceeded can result in Cushing’s syndrome (hypercortisolism), which is associated with massive truncal obesity. Other syndromes (some genetic) can lead to obesity via hormonal dysregulation.
  • Genetic defects – chromosomal genetic defects such as Prader-Willi syndrome can be associated with obesity and diabetes mellitus, among other conditions.
  • Hyperalimentation (overeating) with significantly reduced physical activity – as the most important and most common constellation for the development and maintenance of obesity is the combination of hyperalimentation and reduced physical activity.
  • Disease-related causes
  • Medications – various groups of medications lead to weight gain and even obesity. In particular, antidepressants, which increase the feeling of hunger, the risk of weight gain is high, so that the underlying depression can also be aggravated. Antipsychotics (neuroleptics), lithium, insulin, cortisone, beta blockers, testosterone, estrogen and progestin also increase the likelihood of developing obesity.

For details, see “Obesity/Causes” below.

Therapy

Conservative

Weight-loss programs: The primary goals of weight loss programs are to permanently change dietary behavior and to provide a diet that is appropriate for the patient’s needs. The programs are usually based on a holistic concept and include physical activity and behavioral training in addition to nutrition. Examples of weight loss programs include “Weight Watchers” and “Almased.” Note: In a comparative study (diet versus surgery), diet achieved an equally good effect on glucose metabolism, but avoided some of the disadvantages of surgery: In both groups, insulin resistance was significantly improved in the liver, but also in fat and muscle tissue, with no differences between the two groups.Conclusion: Bariatric surgery is only an option for patients who feel overwhelmed by the change in diet. Various approaches to eating behavior therapy have been reviewed in clinical trials. Maintaining a dietary protocol has been shown to be beneficial. However, without physical activity, eating behavior therapy is severely limited. Drug therapy, including appetite suppressants and fat absorption inhibitors, should be viewed critically because massive side effects can occur in some cases.

Indications (areas of application) for bariatric surgery [according to S3 guideline: Surgery of obesity and metabolic diseases, see below]

  • In patients with a BMI ≥ 40 kg/m2 without concomitant diseases and without contraindications, bariatric surgery is indicated after exhaustion of conservative therapy after comprehensive education.
  • Patients with a BMI ≥ 35 kg/m2 with one or more obesity-associated comorbidities such as type 2 diabetes mellitus, heart failure, hyperlipidemia, arterial hypertension, coronary artery disease (CAD), Nephropathy, obstructive sleep apnea syndrome (OSAS), obesity hypoventilation syndrome, Pickwick syndrome, nonalcoholic fatty liver (NAFLD), or nonalcoholic fatty liver hepatitis (NASH), Pseudotumor cerebri, gastroesophageal reflux disease (GERD), bronchial asthma, chronic venous insufficiency (CVI), urinary incontinence, immobilizing joint disease, fertility limitations, or polycystic ovary syndrome (PCO syndromeM) should be offered bariatric surgery when conservative therapy is exhausted.
  • In certain circumstances, a primary indication for bariatric surgery may be made without a prior attempt at conservative therapy. The primary indication may be given when any of the following conditions exist: in patients.
    • With a BMI ≥ 50 kg/m2.
    • In whom a conservative therapy attempt was classified by the multidisciplinary team as not promising or hopeless.
    • With particular severity of concomitant and secondary diseases that do not allow postponement of a surgical intervention.

Contraindications

  • Unstable psychopathological conditions
  • Untreated bulimia nervosa
  • Active substance dependence
  • Poor general health
  • Lack of indication – should obesity be caused by a disease (e.g., hypothyroidism, Conn syndrome (primary hyperaldosteronism, PH), Cushing’s disease, pheochromocytoma)

Surgical procedures

  • Gastric banding – during gastric banding surgery, a silicone band is placed around the stomach fundus. The diameter of the opening can be changed by filling the band with fluid – through a port, usually located by the rib cage – and a corresponding reservoir is placed in the abdominal wall. By narrowing the diameter of the stomach, a permanent significant weight reduction can be achieved.
  • Roux-en-Y gastric bypass – gastric bypass is performed as a surgical procedure according to Torres and Oca. In order for gastric bypass to occur, the distal (lower) portion of the stomach is removed. Then, the remaining proximal (front) portion is connected via a Y-Roux gastrojejunostomy. The Y-Roux gastrojejunostomy after distal gastric resection consists of, among other things, cutting the first jejunal loop (part of the small intestine); one end of the jejunum is sutured to the gastric remnant via a side-to-side anastosmosis. To create the Y configuration, the feeding jejunal loop is connected more distally to the draining jejunal loop.
  • Tube stomach surgery – in tube stomach surgery, more than 80% of the stomach is surgically removed. Following this, the remaining stomach is made into a tube shape, leaving only an initial filling volume of less than 100 ml.
  • Biliopancreatic diversion (BPD) – biliopancreatic diversion according to Scopinaro is usually indicated only for BMI above 50 kg/m². In this procedure, the residual stomach is joined after partial resection similar to the Y-Roux gastrojejunostomy, but the jejunum is anastomosed later so that only a small distance is left for effective absorption of food components. However, this also results in the disadvantage of the procedure: significant malabsorption (“poor absorption“) of various micronutrients (vital substances). By creating a special duodenal switch (duodenal switch) can prevent a so-called early dumping syndrome (early after eating (about after 30 minutes) occurring symptoms such as nausea, increased sweating, abdominal pain to circulatory problems).

Postoperative effects of bariatric surgery

  • Significant reduction in body weight
  • Decreased secretion of ghrelin: this is produced mainly in the gastric fundus and stimulates the appetite center in the hypothalamus, leading to weight loss.
  • Reduction in the prevalence (disease incidence) of diabetes mellitus type 2; one in four patients with diabetes mellitus type 2 achieved normal glucose levels in a randomized long-term study after surgical stomach reduction or bypass surgery.
  • Improvement in lipid profile: Decrease in LDL particle (LDL-P).
  • Risk reduction of hypertension
    • Obese hypertensives who undergo bariatric surgery can immediately reduce their antihypertensive medication significantly; half even achieve remission of hypertension
  • Risk reduction of cardiovascular events.
    • Elevated serum troponin I levels in severely obese patients decrease to near normal levels after Y-Roux gastric bypass. Comment: The extent to which this leads to a reduction in cardiovascular events remains to be proven.
  • Rheumatoid arthritis: C-reactive protein (CRP) ↓ + need for DMARDS ↓:
    • CRP at baseline 26.1 mg/l; after six months 10.1 mg/l; one year after surgery 5.9 mg/l.
    • Need for DMARDs (Disease-Modifying AntiRheumatic Drugs) before surgery 93%; one year after surgery 59%.
  • Risk reduction for certain tumor types:
    • Risk of developing any form of cancer was about 33% lower than in non-operated subjects
    • The effect was strongest for obesity-related tumor entities (including postmenopausal breast carcinoma (breast cancer), endometrial carcinoma (uterine cancer), colon carcinoma (colon cancer), and carcinomas of the thyroid, pancreas (pancreas), liver, gallbladder, and kidney): Risk reduction of 41%; decrease in risk of carcinoma in men and women combined:
      • Pancreatic cancer risk by 54%.
      • Colorectal cancer risk by 41
      • Specifically female tumors such as breast cancer (decrease of 42%) and endometrial cancer (decrease of 50%)
  • Decrease in urinary incontinence:
  • Decrease in mortality risk (risk of death): 7.7 versus 2.1 deaths per 1,000 persons per year.
  • Risk increase
    • Increase in mental health problems
      • 2.3 times more frequent outpatient treatment for psychiatric disorders (incidence rate IRR 2.3; 95% confidence interval 2.3-2.4)
      • 3 times more likely to have emergency department visits (IRR 3.0; 2.8 to 3.2) or psychiatric hospitalizations (IRR 3.0; 2.8-3.1)
      • 4.7 times more likely to engage in intentional self-injury (IRR 4.7; 3.8-5.7)
    • Increase in suicidality (suicide risk).