Bariatric surgery includes a variety of procedures performed on people who have obesity. Weight loss is achieved by reducing the size of the stomach with a gastric band or through removal of a portion of the stomach (sleeve gastrectomy or biliopancreatic diversion with duodenal switch) or by resecting and re-routing the small intestine to a small stomach pouches (gastric bypass surgery).
Long-term studies show the procedures cause significant long-term loss of weight, recovery from diabetes, improvement in cardiovascular risk factors, and a mortality reduction from 40% to 23%. bariatric surgery for obese people with a body mass index (BMI) of at least 40, and for people with BMI of at least 35 and serious coexisting medical conditions such as diabetes. However, research is emerging that suggests bariatric surgery could be appropriate for those with a BMI of 35 to 40 with no comorbidities or a BMI of 30 to 35 with significant comorbidities.
Surgery should be considered as a treatment option for patients with a BMI of 40 kg/m2 or greater who instituted but failed an adequate exercise and diet program and who present with obesity-related comorbid conditions, such as hypertension, impaired glucose tolerance, diabetes mellitus, hyperlipidemia, and obstructive sleep apnea. A doctor–patient discussion of surgical options should include the long-term side effects, such as a possible need for reoperation, gallbladder disease, and malabsorption
The surgery is contraindicated in patients who have end stage disease and also in patients not committed to make lifestyle changes considered ideal for the surgery.
When determining eligibility for bariatric surgery for extremely obese patients, psychiatric screening is critical; it is also critical for determining postoperative success. Patients with a body-mass index of 40 kg/m2 or greater have a 5-fold risk of depression, and half of bariatric surgery candidates are depressed.
In general, the malabsorptive procedures lead to more weight loss than the restrictive procedures; however, they have a higher risk profile.
- Biliopancreatic diversion — 117 Lbs / 53 kg
- Roux-en-Y gastric bypass (RYGB) — 90 Lbs / 41 kg
- Open — 95 Lbs/ 43 kg
- Laparoscopic — 84 Lbs / 38 kg
- Vertical banded gastroplasty — 71 Lbs / 32 kg
Reduced mortality and morbidity
In the short term, weight loss from bariatric surgeries is associated with reductions in some comorbidities of obesity, such as diabetes, metabolic syndrome and sleep apnea, but the benefit for hypertension is uncertain. It is uncertain whether any given bariatric procedure is more effective than another in controlling comorbidities. There is no high quality evidence concerning longer-term effects compared with conventional treatment on comorbidities.
Bariatric surgery in older patients has also been a topic of debate, centered on concerns for safety in this population; the relative benefits and risks in this population is not known.
Given the remarkable rate of diabetes remission with bariatric surgery, there is considerable interest in offering this intervention to people with type 2 diabetes who have a lower BMI than is generally required for bariatric surgery, but high quality evidence is lacking and optimal timing of the procedure is uncertain.
Laparoscopic bariatric surgery requires a hospital stay of only one or two days. Short-term complications from laparoscopic adjustable gastric banding are reported to be lower than laparoscopic Roux-en-Y surgery, and complications from laparoscopic Roux-en-Y surgery are lower than conventional (open) Roux-en-Y surgery.
Fertility and pregnancy
Bariatric surgery reduces the risk of gestational diabetes and hypertensive disorders of pregnancy in women who later become pregnant but increases the risk of preterm birth.
Some studies have suggested that psychological health can improve after bariatric surgery.
Self-harm behaviors and suicide appear to be increased in people with mental health issues in the 5 years after bariatric surgery had been done.