Published: 12-01-2017 14:16 | Updated: 16-01-2017 09:41

Good long-term results of obesity surgery in young people

Bariatric surgery on teenagers gives results that are equally as good as for adults, but the operations carries complications. Five years after surgery, the patients weighed on average 28 per cent less than beforehand, a new study shows.

“Teenagers and adults who have undergone bariatric surgery exhibit remarkable similarities,” says Torsten Olbers, docent at the Sahlgrenska Academy and consultant at Sahlgrenska University Hospital. “Seriously obese young people who do not have surgery continue instead to increase in weight.”

The study he led compared 81 teenagers who had a so-called gastric bypass with an equal number of teenagers in receipt of conventional treatment and a group of adults who had also had a gastric bypass. 65 per cent were women and 35 per cent men.

The teenagers who were operated on were between 13 and 18 at the time of surgery, with an average age of 16 and an average BMI of around 45. In many cases, their obesity had already caused complications, such as altered blood lipid levels, high blood pressure, fatty liver, type 2 diabetes or a precursor of diabetes.

Considerable weight reduction

“It is the most seriously obese young people we’re talking about, and without surgery virtually all of them remain large for the rest of their lives,” says Dr Olbers. “It is especially evident in the young people that there is a strong underlying genetic predisposition for serious obesity. This is no lifestyle choice they have made.”

The teenagers who did not receive surgery continued to gain weight during the five-year period by an average of 10 per cent, and 25 per cent of them were operated on during the follow-up time since becoming adults. This compares with a 28 per cent weight loss in those who underwent gastric bypass surgery.

However, 25 per cent of the teenagers who had received surgery also suffered complications that required another operation within five years, roughly half of them for ileus and half for gall stones.

“It came as a surprise to us that young people also had gall stones, something that we have seen in adults with severe weight loss,” says Dr Olbers. “The young people also had the same frequency of ileus as the adults, a complication that we can now prevent by closing the so-called ‘slits’ during surgery.”

Follow-up and support

The operation, which is performed using keyhole surgery, takes roughly an hour and involves attaching the small intestine to a small gastric pocket just under the oesophagus. The stomach is left in place, and produces gastric juices that enter the system, along with the bile etc., further down. This means that in effect ingested food passes direct into the intestines.

“It’s not that the system comes to a stop,” explains Dr Olbers. “The operation changes the basic signals of hunger and satiety. You don’t get so hungry and feel full more quickly, even in your mind.”

There is, however, a risk of vitamin and mineral deficiency after a gastric bypass owing to the reduction in food intake and the re-connection of the intestines. This was obvious in the young people, who tended not to take the recommended supplements.

“It’s essential that we continue to monitor these young people, especially as they have many decades of life left ahead of them,” adds Dr Olbers.

The study followed up patients at several locations around the country and also involved researchers at Lund University and Karolinska Institutet, where Claude Marcus is professor of paediatrics.

“It’s time to start integrating bariatric surgery with the treatment of seriously obese young people,” he says. “But they must be monitored over the long term since our results also show that some young people need a lot of support to handle the post-operative situation. Bariatric surgery is no quick fix.”


Laparoscopic Roux-en-Y gastric bypass in adolescents with severe obesity (AMOS): a prospective, 5-year, Swedish nationwide study
Dr Torsten Olbers, PhD; Andrew J Beamish, MD; Eva Gronowitz, PhD; Carl-Erik Flodmark, PhD; Jovanna Dahlgren, PhD; Gustaf Bruze, PhD; Kerstin Ekbom, PhD; Peter Friberg, PhD; Gunnar Göthberg, PhD; Kajsa Järvholm, PhD; Jan Karlsson, PhD; Staffan Mårild, PhD; Martin Neovius, PhD; Markku Peltonen, PhD; Claude Marcus, PhD.
Published online 5 January 2017, The Lancet Diabetes & Endocrinology, DOI: