Is There a Reason to Delay Bariatric Surgery in Obese Teens?

Adolescents and adults saw similar amounts of weight loss after bariatric surgery, according to findings from a 5-year study.

Following Roux-en-Y gastric bypass, adolescent patients had an average drop in weight of 26% (95% CI -29% to -23%), compared with 29% in adults (95% CI -31% to -27%) (P=0.08), reported Thomas Inge, MD, PhD, of the University of Colorado in Denver, and colleagues.

As the team reported online in the New England Journal of Medicine, adolescents also tended to have higher remission rates for comorbidities than adult patients did, as follows:

• Type 2 diabetes: 86% vs 53%; risk ratio 1.27 (95% CI 1.03-1.57)

• Hypertension: 68% vs 41%; RR 1.51 (95% CI 1.21-1.88)

However, this was offset by adolescents having a significantly higher rate of intra-abdominal reoperations within 5 years of the initial surgery compared with adult patients (19.5 per 500 person-years, 95% CI 12.8-29.8, vs 10.3, 95% CI 6.8-15.7).

The types of reoperations — cholecystectomy, surgery for bowel obstruction, repair of internal hernia, and gastrostomy — were not significantly different between the two age groups.

The analysis included 161 adolescents under age 19 who were enrolled in the Teen-Longitudinal Assessment of Bariatric Surgery (Teen-LABS) study, and 396 adults ages 25-50 enrolled in the LABS study. At baseline, the average body-mass index was 50 for both adolescents and adults, dropping down to 37 and 36, respectively, at 5 years postoperatively.

Two years after surgery, 48% (95% CI 37%-63%) of adolescents also had low ferritin levels compared with only 29% (95% CI 23%-36%) of adults. Also, 38% (95% CI 28%-51%) of adolescents had low levels of total 25-hydroxyvitamin D compared with 24% (95% CI 18%-32%) of adults.

These differences in nutritional measures between the age groups may be attributed to younger patients’ lack of adherence to vitamin and mineral supplementation after surgery, which the researchers said decrease considerably within the first months after surgery among adolescents.

“The differences in ferritin and vitamin D levels at 2 years may be related to better adherence to postoperative vitamin and mineral supplementation among adults,” the team said. “Thus, over time, the incidence of nutritional deficiencies among adolescents might decrease, if adherence to supplements improves with their emergence into adulthood.”

The mortality rates didn’t differ between the age groups; three adolescents (1.9%) and seven adults (1.8%) died within 5 years of surgery. Two of the adolescent deaths were directly related to a drug overdose, which the author of an accompanying editorial, Ted Adams, PhD, MPH, of Intermountain Healthcare in Salt Lake City, called “troubling.”

“In parallel with the well-documented, long-term favorable weight change outcomes of bariatric surgery in adults, bariatric surgery in adolescents who are severely obese is equally successful with respect to weight loss and appears to be associated with an even greater long-term disease remission if surgery is not delayed until adulthood,” Adams wrote.

In addition, he noted that the “negative health outcomes of bariatric surgery reported in adolescents also mirror those reported in adults — including, for example, the potential for self-harm (including suicide) and increased risk of alcohol or drug abuse.”

Although Adams called the study “clinically important,” he cautioned about considering bariatric surgery a one-size-fits-all approach to adolescent obesity. “Adolescent patients may not have fully developed the capacity for decision making, especially about a procedure that will have lifetime consequences,” he said.

Ultimately, he recommended that providers approach patients on a “case-by-case basis, with the knowledge that the 5-year data look promising but that the lifetime outcome is unknown.”

last updated 05.16.2019