What patients need to know about bariatric surgery – Part 3

In the final part of our series, we look at the benefits and the long-term success of bariatric surgery

By Dr Abeezer Sarela

Benefits of surgery

The extent of weight loss can be 30-40% of body weight (35-45 kg for a 120kg person). Most of the weight loss occurs during the first year after the operation. There may be some further weight loss during the second year and a plateau is then reached. The true benefit of surgery is better measured in terms of the cure of obesity-related illnesses and improvement in quality of life.

The most dramatic effect is on diabetes – diabetes is cured (i.e. blood sugar remains normal without any medication) in 80% of diabetic patients. High blood pressure and high cholesterol may be cured in 60-80% of patients. Even if the disease is not completely cured, it often becomes less severe and is better controlled with less medication.

Marked improvement or cure is also seen in cases of fatty liver, obstructive sleep apnoea, obesity hypoventilation and infertility. Treatment of obesity can help with arthritis (joint pains) and reduce the risk of several cancers and heart attack. Large studies have shown that bypass patients live considerably longer than obese persons who did not have surgery.

Long-term success of surgery: What is the chance of weight re-gain?

The majority of bariatric surgery patients maintain the weight loss, lifelong. A healthy diet and regular exercise are very important for long-term success in weight-control. Large studies have shown that about 25% of patients do regain some of the lost weight, during long-term follow-up. The weight regain is usually partial (e.g. a person, who originally lost 45 kg, regains 10 kg at 8 years after the operation) so that a large part of the benefit of bariatric surgery is maintained.

There can be several causes for weight regain: often, there is failure to follow the advice of the doctor or dietician. Structural problems, such as widening of the reduced stomach, are uncommon after gastric bypass or sleeve gastrectomy but can occur – in such cases, further surgery (called revisional surgery) or endoscopy procedures are available. 

Which operation should I have?

The laparoscopic gastric bypass is the ‘gold-standard’ bariatric operation. There is detailed, long-term information about the efficacy and safety of this procedure. The bypass is a technically demanding procedure that should be performed by only an expert surgeon.

In contrast to the bypass, the sleeve gastrectomy is a relatively new procedure and information beyond five years is not currently available. The extent of weight loss with the sleeve gastrectomy appears similar to that with the bypass in the initial few years after surgery, but longer term issues are unclear. In comparison to the bypass, the sleeve is a technically simpler operation and requires use of fewer stapling instruments. In super-super-obese patients (BMI more than 60 kg/m2), the sleeve can be a safer operation than the bypass. Another advantage of the sleeve, for super-super obese, is that if there is inadequate weight loss after the operation, then further surgery can be done (the sleeve can be converted into a bypass or another operation called a ‘duodenal switch’). Following a bypass, further surgery is not usefully helpful.

The gastric band is attractive because it technically simple to insert, has very low risk of complications and is easily reversible. However, banding usually provides less weight loss than the bypass or sleeve, requires intensive follow-up and has high-risk of long-term complications. There is no clear-cut right or wrong choice of operation and this issue requires detailed discussion to suit the particular needs of an individual patient.

Dr Sarela is a bariatric surgeon at Hinduja Hospital, Mumbai

Picture credit: Pascal Thauvin