The worldwide incidence of bariatric surgical procedures, also known as slimming or weight loss surgery, has increased more than fivefold in five years in most developed countries and research evidence shows it reduced risk of death in severely obese patients, suggest two scientists reviewing the latest research.
Dr Michael Korenkov, of the Department of Abdominal Surgery, University of Mainz in Germany, and Dr Stefan Sauerland from the Institute for Research in Operative Medicine, University of Witten/Herdecke, also in Germany, explore the issues surrounding the controversial approach to weight loss in the 15th December issue of The Lancet, available now as online premium content.
In their Clinical Update article, Korenkov and Sauerland refer to two cohort studies by Lars Sjöström and Ted Adams published in the
Korenkov and Sauerland explore the two types of bariatric surgery: the gastric-restrictive type, which limits food intake; and the malabsorption type, which decreases the amount of food absorbed in the digestive tract.
They suggest the choice of which surgical procedure is taken “partly depends on the repertoire of the surgeon” because “most surgical centres cannot offer the full range of possible operations”. They also suggest that different types of procedure are commonly used in different parts of the world.
Traditionally, the effectiveness of a surgical procedure to manage weight has only been measured in terms of the weight reduction, for which the evidence overwhelmingly points to success.
However, Korenkov and Sauerland say that nowadays there is a trend toward looking at the effect of surgery on “obesity-related comorbidities, which can affect metabolic, cardiovascular, respiratory, gastrointestinal, musculoskeletal and urological organ systems”.
“New data indicate that at least some bariatric procedures exert their beneficial metabolic effects not only by weight loss but also through a change in hormone release from the gut,” wrote Korenkov and Sauerland.
“This finding corresponds to clinical observations that obesity in patients with diabetes is especially amenable to bariatric surgery,” they added.
Also being taken into account are the psychological effects of bariatric surgery, they wrote.
The authors suggest that as with other surgical fields, the expertise of the surgical team is key to the success of a bariatric procedure, and they call for more centres with concentrated knowledge and skills, because:
“Mortality in high-volume centres is lower than in lower-volume centres.”
Overall Korenkov and Sauerland suggest the evidence that bariatric surgery is more effective than non-surgical approaches to morbid obesity is good. But, they also offer a word of caution:
“No single operation is ideal for every morbidly obese patient, and all operations also entail some disadvantages.”
According to the Cleveland Clinic, a person is considered a candidate for weight loss surgery if their body mass index (BMI) is over 40, that is about 100 pounds overweight for men and about 80 pounds overweight for women. This BMI range is classed as “severely obese”.
People with a BMI of 35 to 40 may also be potential surgery candidates if they suffer from life threatening health problems such as severe sleep apnea, obesity-related heart disease, or diabetes. Motivation and behaviour are said to be key factors to success.
According to the American Society for Bariatric Surgery (ASBS), the number of Americans having weight loss surgery has increased from around 16,000 in the early 1990s to more than 103,000 in 2003.
“Clinical update: bariatric surgery.”
Michael Korenkov, Stefan Sauerland
The Lancet, Vol. 370, Issue 9604, 15 December 2007, Pages 1988-1990.
Click here for more information on weight loss surgery (MedlinePlus).
Written by: Catharine Paddock