WASHINGTON — Early experience suggests that the health benefits of bariatric surgery offset the risks for severely obese adolescents, based on the results of small studies reported at the annual scientific sessions of the American Diabetes Association.
Significant metabolic improvements and near-complete resolution of type 2 diabetes and obstructive sleep apnea were among the 1-year outcomes of Roux-en-Y gastric bypass surgery performed in 36 morbidly obese adolescents, aged 13–21, at three pediatric surgical centers participating in the Pediatric Bariatric Study Group.
Severely obese adolescents are developing serious adultlike comorbidities at an unexpectedly high frequency. Limited success with behavioral and lifestyle interventions has left physicians considering more aggressive interventions. “Children who are obese become obese adults,” said Dr. Carroll M. Harmon, of the Children's Hospital of Alabama, Birmingham.
Teens were eligible for the surgery at Children's Hospital and the other institutions in the Pediatric Bariatric Study Group (the University of Florida in Gainesville and the Cincinnati Children's Hospital Medical Center) if they had a body mass index (BMI) of at least 40 kg/m
The teens in the multicenter cohort had a mean BMI preoperatively of approximately 57. Postoperatively, the mean BMI fell to 36, a 37% reduction.
None of the patients included in the weight loss analysis (9 of the 36 teens in the cohort were excluded because they did not comply with follow-up requirements) attained normal weight in the year of follow-up; BMI values, in fact, still ranged from overweight to severe obesity.
Still, the postoperative weight loss was significant and consistent with outcomes in adults who undergo bariatric surgery, said Dr. Harmon, professor of surgery in the University of Alabama division of pediatric surgery.
Metabolic measures improved as a result of significant decreases in triglycerides (−65 mg/dL), total cholesterol (−30 mg/dL), fasting blood glucose (−12 g/dL), and fasting insulin (−21.3 μU/mL). Changes in HDL and LDL cholesterol values were not statistically significant.
Mean hemoglobin A1c decreased from 7.3% to 5.6% in the 10 patients diagnosed with type 2 diabetes. At 1 year after surgery, 1 of 10 patients remained on diabetic medications; 9 of 10 were on diabetic medications preoperatively, Dr. Harmon reported.
The adolescents also scored significantly higher postoperatively on various quality-of-life measures than they did preoperatively, he added.
In a separate poster presentation, Dr. Marc P. Michalsky and Dr. Dara Schuster of Ohio State University, Columbus, reported on what they said are similarly good outcomes in five morbidly obese adolescents (BMI of at least 57) who underwent Roux-en-Y gastric bypass surgery at Columbus Children's Hospital.
Serum hemoglobin A1c reached normal values within 20 weeks of surgery in each of the four adolescents with type 2 diabetes. Blood pressures reached normal values within 20 weeks in each of four hypertensive patients, and obstructive sleep apnea resolved after surgery in two of three affected patients. Insulin resistance (as determined by calculating the homeostasis model assessment of insulin resistance) also was reduced by a mean of 66% at 12 weeks post surgery.
“These are superobese kids,” and they have the same morbidities as obese adults who qualify for gastric bypass surgery, Dr. Schuster said in an interview. “The question we need to answer is: Do we do them a favor by operating early?”
Long-term follow-up, each of the physicians emphasized, will be necessary to determine both the durability of the patients' improvements and the safety of the surgery. Whether the patients will experience nutritional malabsorption is a question, they noted.
None of the five adolescents treated in Columbus experienced complications during the 20-week follow-up period, but there were complications among the 36 who were followed for a year.
Nine of the 36 patients had “minor” complications with no long-term sequelae (nausea, wound infection, and food obstruction), and 4 had at least one “moderate” complication (persistent iron-deficiency anemia or the need for reoperation).
Two patients, Dr. Harmon reported, had severe complications: One developed severe thiamine deficiency with significant sequelae, and the other, who initially presented with a BMI of 80 and a weight of 630 pounds, died 9 months after surgery due to infectious colitis contracted while undergoing inpatient rehabilitation for osteoarthritis.
The complication profile thus far is similar to that seen in superobese adults who undergo the surgery, Dr. Harmon said. Among adults, 0.2%–2% die from the surgery and more than 15% experience complications.
“The risks are still considerable, but so far in adolescents, just as in adults, these risks seem to be offset by the benefits,” said Dr. Harmon. “It's encouraging.”
The adjustable gastric banding procedure, which does not involve an intestinal bypass, is getting more attention as a possible “best” operation for adolescents—even though long-term results in adults have not been compared with those of gastric bypass surgery—because it eliminates concerns about nutritional and mineral malabsorption, Dr. Harmon said.