Teens Gain Big Benefits From Bariatric Surgery

Los Angeles—In the largest and longest study to date of bariatric surgery in adolescents, teenage patients experienced major improvements in weight loss, metabolic health and quality of life up to three years after surgery, with some benefits that eclipse those reported for adults.

The study was published in the Nov. 6 online edition of The New England Journal of Medicine and was presented simultaneously at ObesityWeek 2015.

“With this study, we’re able to supply some hard evidence of durable weight loss efficacy and durable change in comorbidities for at least up to three years after surgery,” said lead author Thomas Inge, MD, PhD, director of the surgical weight loss program for adolescents at Cincinnati Children’s Hospital Medical Center.

“We really do see those gratifying changes that you might expect or hope for when you’re operating on a teenager with a weight, on average, of 325 pounds.”

Three years after surgery, the young patients’ average weight dropped by more than 90 pounds, or 27%. Most teenagers also had improvements in several key obesity-related health problems: 95% experienced a reversal in type 2 diabetes and 86% had normalization of kidney function. Hypertension improved in 74% of patients and lipid abnormalities reversed in 66%.

The remission rates for diabetes and hypertension are greater than those reported in high-quality studies of adults who had long-standing obesity before bariatric surgery. Studies show that 50% to 70% of adults who undergo gastric bypass will have remission of diabetes, far lower than the numbers reported in this trial.

Study investigators and bariatric surgeons who heard the study presented said the findings suggest that teenagers may benefit more by undergoing surgery while young instead of waiting until adulthood, when the metabolic effects of obesity are more entrenched.

“These improvements with regard to weight, glycemic control, blood pressure and dyslipidemia in adolescents may mitigate the progression of adverse anatomical and physiological cardiovascular changes, changes that may be less reversible after the accumulation of more pound-years later in life,” said Dr. Inge.

Launched in 2007, the Teen-LABS (Teen-Longitudinal Assessment of Bariatric Surgery) study is the most comprehensive analysis of bariatric outcomes in adolescents conducted to date. Most previous studies have been retrospective and were limited by short and often patchy follow-up.

In this study, investigators enrolled 242 adolescents, aged 13 to 19 years, who were severely obese with an average weight of 325 pounds and average body mass index (BMI) of 53 kg/m2 before surgery. They underwent a mix of the most commonly performed bariatric surgery operations: 161 had Roux-en-Y gastric bypass, 67 had a sleeve gastrectomy and 14 underwent adjustable gastric banding. Gastric banding patients were excluded from the main analyses because of small numbers.

The data presented were based on three-year follow-up, although many patients have now been tracked for more than five years as the study is continuing. Follow-up was unusually good, with 85% of participants completing their three-year postoperative clinical visits.

Analysis revealed that surgery was not without long-term risks, even among teenagers with successful weight loss. Three years after surgery, more than half of the participants had low ferritin stores, up from the fewer than 5% who were iron deficient before surgery. Vitamin B12 levels declined by 35%, and 8% of the participants had a deficiency at three years.

Dr. Inge said the micronutrient changes seen in the teenagers resembled those reported in adults, although the teenagers tended to not have developed frank anemia. “We’re not seeing actual anemia yet in any high percentage, but we are seeing an impact of the procedures on iron stores.

“The good news is that we have an opportunity to sound the alarm and be able to use this as solid evidence that iron and multivitamin supplements are needed for both gastric bypass and sleeve gastrectomy patients. We know that despite our recommendations, patient adherence is pretty poor for vitamin and mineral supplements.”

The study also demonstrated that some teenagers who undergo bariatric surgery will require additional abdominal surgery within the first years afterward. Of the study participants, 13% required at least one additional abdominal procedure during the three-year period, most commonly gallbladder removal. In all, 30 patients required a total of 47 additional procedures.

One patient with known type 1 diabetes died 3.3 years after gastric bypass surgery from complications of a hypoglycemic event. It was the only death in the series.

Samer Mattar, MD, professor of surgery and chief of the bariatric services program at Oregon Health & Science University, in Portland, hoped the findings will encourage more primary care physicians to refer teenagers for bariatric surgery.

“We have 4.5 million severely obese children in the United States. When severe obesity affects people at such a young age, comorbidities latch on and set in so that by the time they are adults, they are experiencing the full ravages of chronic disease. These are tomorrow’s health crises. I think this paper is evidence that we should be operating on more of these adolescents before they become severely compromised young adults,” Dr. Mattar said.

Although bariatric surgery is performed on unprecedented numbers of teenagers today, the number of procedures performed—and the availability of insurance coverage—barely registers compared with the size of the obese population of young Americans. The last available figure suggests that 1,600 bariatric procedures were performed on people younger than 19 years of age in 2009.

There are many reasons why bariatric surgery is less frequently performed and less widely accepted for teenagers than adults. Of note, few prospective studies have examined changes in BMI and other long-term outcomes in children who undergo bariatric surgery. Most studies have been retrospective and have not followed clinical events beyond one year.

Pediatricians who specialize in childhood obesity lauded the study but said they want to see more support for nonsurgical, evidence-based options of behavior management for teenagers before referring these patients for surgery. They remain concerned about the long-term effects of surgery, including iron deficiency, weight regain and possible fertility issues.

“I cringe at the thought that we would push the surgical options further without first pursuing the medical options,” said Stephen Cook, MD, MPH, associate professor of pediatrics, University of Rochester, in New York, and associate director of the Institute for Healthy Childhood Weight, American Academy of Pediatrics.

He worries about low folate and iron levels in teenagers after bariatric surgery, as they may affect a young woman’s ability to bear healthy children. “Three-quarters of this study group were female. You have to look very closely at the health risks for their offspring if the mom has significant nutrition deficiencies,” he said.

He added that bariatric surgery “does show promise,” but needs to be conducted at pediatric multidisciplinary centers that incorporate the patient’s family into care and monitor long-term effects.

“Bariatric surgery needs to be treated at a very high level of risk, despite the good outcomes. I would treat this procedure on par with organ transplant. You need to have the family well on board, and they need to be able to show improvement that indicates they can be compliant.”

Sarah Barlow, MD, associate professor of pediatrics at Baylor College of Medicine, in Houston, who refers patients to one of the surgeons participating in the trial, said she wanted to see the study lead to more access, and more equal access, to bariatric surgery.

“There should be greater access to high-quality surgery at sites taking care of adolescent patients and their families,” she noted. “Severe obesity is more common among African American and Hispanic children, but currently the majority of adolescents who undergo bariatric surgery are white. There may be many reasons for this, including the population around the current sites, but we need to ensure that availability and coverage are fair.”

She stressed that many severely obese children do not have access to the lifestyle programs that should precede consideration of bariatric surgery. There are payors who will provide insurance coverage for surgery for teenagers but not intensive counseling or nutrition counseling for children and adolescents, she said. “It would be a disservice to children if primary care providers could easily refer to bariatric surgery but had no place to refer for comprehensive, multicomponent behavior-based treatment.”

The patients in the study reported improvements in weight-related quality of life at the three-year mark after surgery. The mean quality of life score rose from 63 at baseline to 83 three years later.

Dr. Inge stressed the need for a specialized adolescent bariatric team to care for children who undergo weight loss surgery. “I have no doubt that the adult bariatric surgeons are going to be technically proficient, just like they are for performing adult surgery, but it’s a team with a pediatric focus on the front end and back end of surgery that’s important.”

The youngest patient in the study was 13 years of age. There is no broadly accepted start age for bariatric surgery, although most experts argue that patients should have reached puberty and can demonstrate the emotional and psychological maturity to comply with vitamin and eating requirements.

The adolescents in this study were operated on between March 2007 and February 2012 at participating centers. In the latter years of the study, more surgeons adopted sleeve gastrectomy as their procedure of choice, including teenagers. That may reduce the long-term nutritional deficiencies shown in the study, said James M. Swain, MD, medical director of Honor Health Bariatric Center, in Scottsdale, Ariz., and clinical associate professor of surgery at the University of Arizona School of Medicine, in Phoenix.

“I believe the sleeve is becoming the procedure of choice in adolescents. To me, you’re going to find, in the end, less nutritional issues related to the sleeve but that’s a question to be answered later,” Dr. Swain said. “To me, this is a landmark project and the data coming out are very good.”