After Bariatric Surgery Teens See Improvements in Diabetes, Hypertension

Thomas Inge, MD, PhD

Teens and adults who underwent gastric bypass surgery had similar weight loss, but the teens were significantly more likely to experience remission of type 2 diabetes and hypertension than the adults.

"Type 2 diabetes in youth has been a growing problem without a solution, hitting young adults with serious health conditions when they should be in the prime of their lives. This study demonstrates that bariatric surgery may provide an effective treatment, though not one without risks," said Griffin P. Rodgers, MD, Director of NIH's National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), which was the primary funder of the study.

Both groups had similar rates of weight loss—teens lost 26% of their bodyweight (95% Confidence Interval, -29% to -23%), while adults lost 29% of their bodyweight (95% CI, -31% to -27%) 5 years after the surgery (P = .08). However, teens were significantly more likely than adults to experience remission of type 2 diabetes (86% versus 53%; risk ratio, 1.27; 95% CI, 1.03 to 1.57).

Additionally, the study reported that before the surgery, 88% of teens and 79% of adults used diabetes medications—after surgery those decreased to 0% and 26%, respectively (P <.001).

"Obesity increases the risk for type 2 diabetes and cardiovascular diseases, and these conditions can be more difficult to manage in young people," said Mary Evans, PhD, a study author and program director in the NIDDK Division of Digestive Diseases and Nutrition. "We found earlier bariatric surgery in carefully selected youth may have greater benefits compared to waiting until later in life."

The study evaluated patients participating in LABS (Longitudinal Assessment of Bariatric Surgery) and Teen-LABS, 2 NIH-funded programs to evaluate short- and long-term risks and benefits of bariatric surgery. The research included 161 teens under the age of 19 at the time of their surgery and 396 adults who reported having obesity by the age of 18.

In addition to remission of diabetes, teen patients were significantly more likely to experience remission of high blood pressure than adults (68% versus 41%; risk ratio, 1.51; 95% CI, 1.21 to 1.88). Before surgery, 57% of teens and 68% of adults used blood pressure medications. Five years later, 11% and 33%, respectively needed blood pressure medications.

Teen patients were also more likely to require further abdominal operations than adults—19 versus 10 reoperations per 500 person-years (P = .003). About half of the surgeries in each group were gallbladder removals.

Data about patient nutrition was only available through 2 years post-bariatric surgery. At baseline, 98% of teens and adults had normal ferritin levels, but by 2 years later, teens more often had low ferritin levels than adults (48% versus 29%; P = .004). At baseline 25% of teens and 36% of adults had low total 25-hydroxyvitamin D levels, but 2 years after surgery, those increased to 38% among teens and decreased to 24% among adults (P = .02).

While Rodgers noted that there are risks for teens undergoing gastric bypass surgery, first author Thomas Inge, MD, PhD, Children’s Hospital of Colorado, pointed out that the results show strong benefits for many teenage patients with obesity.

"Although there are risks associated with bariatric surgery, this study demonstrates that, for many young people, the benefits likely outweigh the risks," said Inge. "Sufficient vitamin and mineral supplementation, along with continued medical care, can help mitigate some of these risks."

The investigators noted that the observational study design and lack of nonsurgical controls must be taken into consideration with the results. They called for further research and longer-term follow-up to better understand the benefits and risks of bariatric surgery in teens.

"We hope future research continues to shed light on the best timing and the most effective treatments for all people with weight-related conditions," added Rodgers.

The study, “Five-Year Outcomes of Gastric Bypass in Adolescents as Compared with Adults,” was published in the New England Journal of Medicine.