Comparing Gastric Bypass Outcomes in Adolescents and Adults

Studies have shown that adults with obesity who were obese as adolescents have worse medical outcomes than persons who became obese in adulthood (Nat Rev Endocrinol 2018; 14: 183-8; NEJM 2011; 365; 1876-85). Thus, the question is whether earlier intervention would improve outcomes.

A recent study (TH Inge et al. NEJM 2019; 380: 2136-45, editorial TD Adams, pgs 2175-7) compares the 5-year outcomes of adolescents (n=161) and adults (n=396) who underwent Roux-en-Y gastric bypass (RYGB). The two prospectively enrolled cohorts were participants in two related but independent studies.

Key findings:

  • There was similar weight loss in both groups at the 5-year mark: -26% in adolescents and -29% in adults
  • Adolescents had greater remission in both type 2 diabetes (86% vs 53%) and in hypertension (68% and 41%).
  • Three adolescents (1.9%) and seven adults (1.8%) died in the 5-years after surgery.  Two of the adolescents deaths were consistent with overdose.
  • Reoperations were significantly higher in adolescents than adults (19 vs 10 reoperations per 500 person years). The authors comment that the reason for this finding is unclear, possibly related to recall bias or closer monitoring of the adolescents.
  • Nutrient deficiencies were common in adolescents at followup. After 2 years, 48% of adolescents had low ferritin compared with 29% of adults (98% of participants had normal ferritin prior to RYGB. The authors note that  this is likely related to adherence to vitamin/mineral supplementation (which is needed lifelong).

Limitations: observational study design

The associated commentary::

  • “Almost 6% of adolescents in the U.S. are severely obese and  bariatric surgery is now the only successful long-term management…Negative health outcomes of bariatric surgery reported in adolescents mirror those reported in adults — including, for example, potential for self-harm (including suicide) and increased risk of alcohol or drug abuse.”
  • “Adolescent patients may not have fully developed the capacity for decision making, especially about a procedure that will have lifetime consequences.”

My take: This study and commentary point out some clear health benefits for adolescents who undergo RYGB. Given the lifelong need for monitoring and adherence with medical treatment as well as some of the negative health outcomes, it is also clear how challenging it is to proceed with RYGB in teenage years.

Related blog posts:

Square in Toledo, Spain


Treating diabetes with surgery

Two articles in the New England Journal of Medicine point to the role of bariatric surgery in  treating type 2 diabetes in obese patients (NEJM 2012; 366: 1567-76 & 1577-85).  Type 2 diabetes looms as one of “the most challenging contemporary threats to public health.”

The first study was a randomized nonblinded single-center trial with 150 patients; mean BMI 36 with 34% having a BMI less than 35.  Intensive medical therapy was compared to Roux-en-Y gastric bypass or sleeve gastrectomy.  Mean patient age was 49 years. 42% of the gastric bypass group, 37% of the sleeve-gastrectomy group, and 12% of the medical treatment group achieved the primary end-point of a glycated hemoglobin level of ≤6% by the 12 month followup; the average starting glycated (HgbA1C) hemoglobin was 9.2%.  At the conclusion of the study, the average HgbA1C was 6.4, 6.6, and 7.5 respectively in the three groups.

The second study used a similar trial with 60 obese patients; all had BMI >35  At 2 years, diabetes remission occurred in 75% of their gastric bypass group, 95% of their biliopancreatic-diversion group and in no patients receiving intensive medical therapy patients. HgbA1C had similar rates of improvement as the 1st study: 6.3 in gastric-bypass, 4.9 in biliopancreatic-diversion group, and 7.7 in medical-therapy group.

While surgery has risks (see related material below), its benefits are likely to alter future treatment strategies with surgery being contemplated prior to exhausting all medical treatments.

Additional References:

  • -JAMA 2012; 307: 56-65.  Bariatric surgery and long-term cardiovascular events.
  • -JAMA 2011 [doi: 10.1001/jama.2011.817]). Large study failed to show that roux-en-Y gastric bypass prolonged life. n=850 VA pts to 41,244 controls. Same group showed no cost savings during initial 3 yrs: Med Care 2010; 48: 989-98.
  • -NEJM 2011; 365: 1365. Increased frequency of bariatric surgery in adolescents.
  • -NEJM 2009; 361: 445/520. perioperative safety.
  • -NEJM 2007; 357: 741, 753, 818. Bariatric surgery improves mortality rate.
  • NEJM 2007; 356: 2176. Review

Complications from surgery:

  • Early: bowel obstruction, DVT, GI bleed, leaks, pulmonary embolism, wound infection
  • After 30 days: anastomotic stricture, bowel obstruction, gallstones, dehiscence, fistula, Bleeding, Incisional hernia, nutrient deficiencies (iron, B12; calcium, Vit D (w RYGB), folate, B6/riboflavin).
  • Complications from gastric band: food impaction, erosion (now banned in Finland!), band slippage, gastric volvulus, band too tight, port infection
  • Roux-y gastric bypass:
    anastomotic leak 1.2%, anastomotic ulcers/stricture
  • Nutrient Monitoring–every 3months x 3, then yearly: Vitamin A, B12, Folate, Ceruloplasmin, Vit D-25OH, Iron studies, Zinc, thiamine, Selenium, Intact PTH, Mg, PT/PTT
  • Suggested supplements: Calcium c vitamin D 1200-2000mg, Iron at least 18-27mg/day, MVI with zinc/selenium
  • Also if duodenal switch, add Vitamin A 10,000 IU, and Vitamin D3 1200units daily or 50,000 units weeekly, Vitamin K 300 mcg,

Potential nutritional deficiencies:

  • B12, B6 (pyridoxine), Riboflavin (B2), B1 (Thiamine), Folate (B9)
  • Vitamins A,D,E, K
  • Calcium, Copper, Iron, Selenium, Zinc

Recommendations from NASPGHAN Post-Graduate Course 2011:

  • If post-op pain: epigastric –>do EGD & if neg do ‘RUQ w/u’, RUQ –> check U/S, LFTs possibly CT
  • If post-op vomiting –>do EGD
  • If post-op nausea –>Rx PPI and EGD if not improving
  • Anastomotic stricture in stomach –>dilate to 10-12mm in 1 session

Related blog posts (includes additional references)

Cardiovascular disease for the entire family

Staggering cost of obesity

A liver disease tsunami

Lower leptin with physical activity