Low iron, mild anemia seen in adolescent gastric bypass patients

More than 5 years after undergoing Roux-en-Y gastric bypass as adolescents, patients presented with low iron stores and mild anemia more commonly than their nonoperative counterparts, although both groups had nutritional deficiencies, according to study results presented at the Pediatric Academic Societies and Asian Society for Pediatric Research annual meeting.

“These data emphasize the importance of monitoring for nutritional deficiencies regularly in adolescents after gastric bypass. Adherence to nutritional supplements is known to be low in adolescents in general, so it is important to encourage adherence and help the adolescent identify barriers to adherence and strategies to overcome them,” Stavra A. Xanthakos, MD, medical director of the Surgical Weight Loss Program for Teens at Cincinnati Children’s, told Endocrine Today in an email interview.

Stavra A. Xanthakos

The Follow-up of Adolescent Bariatric Surgery-5+ (FABS-5+) study looked at 79 age- and sex-matched patients who were obese at baseline; of those, 28 were nonoperative and 51 underwent Roux-en-Y gastric bypass (RYGB) between 2001 and 2007. At 8-year mean follow-up, anemia (3.7% nonoperative vs. 45.1% operative, P<.01) and hypoferritinemia (48.2% nonoperative vs. 68.1% operative; P<.01) were more common among patients who underwent RYGB.

In both groups, nutritional deficiencies were seen, including similar rates in hypovitaminosis B12 and D and low absolute lymphocyte count; nonoperative participants had a significantly higher rate of low folate, according to the study.

“Severe obesity in teens is associated with nutritional deficiencies, both in teens who have had bariatric surgery and those who have not,” Xanthakos said. “These teens, even those who do not pursue bariatric surgery, should be counseled about this risk and screened for the most common problems, including low iron and vitamin D. A healthy, balanced diet is the best way to prevent nutritional deficiencies from occurring, but once deficiencies are present, nutritional supplements may be prescribed to help bring levels back to normal ranges.”

Xanthakos said vertical sleeve gastrectomy (VSG) may be a viable option for adolescents with obesity because it does not alter the intestine.

“VSG results in nearly as much weight loss as gastric bypass but may carry a lower nutritional risk, as it does not route food past the first part of the small intestine where many nutrients, like iron, are best absorbed,” she said. “Patients who are found to have particularly severe nutritional deficiencies prior to bariatric surgery, such as iron deficiency anemia or severely low vitamin D, or who are known to struggle with adherence to medications, may be better candidates for VSG than a bypass.”

Currently, the same recommendations for taking nutritional supplements exist for both surgical procedures, and long-term studies must be completed on VSG and RYGB, Xanthakos concluded.

For more information:

Inge TH. #2865.8. Presented at: Pediatric Academic Societies and Asian Society for Pediatric Research annual meeting; May 3-6, 2014; Vancouver, British Columbia.

Disclosures: Inge reports funding from a grant by Endo-Ethicon.