title: Insulin Sensitivity and β-Cell Function Improve after Gastric Bypass in Severely Obese Adolescents.
abstract: OBJECTIVE
  To test the hypothesis that insulin secretion and insulin sensitivity would be improved in adolescents after Roux-en-Y gastric bypass (RYGB).
  
  
  METHODS
  A longitudinal study of 22 adolescents and young adults without diabetes undergoing laparoscopic RYGB (mean age 17.1 ± 1.42 years; range 14.5-20.1; male/female 8/14; Non-Hispanic White/African American 17/5) was conducted. Intravenous glucose tolerance tests were done to obtain insulin sensitivity (insulin sensitivity index), insulin secretion (acute insulin response to glucose ), and the disposition index as primary outcome variables. These variables were compared over the 1 year of observation using linear mixed modeling.
  
  
  RESULTS
  In the 1-year following surgery, body mass index fell by 38% from a mean of 61 ± 12.3 to 39 ± 8.0 kg/m(2) (P < .01). Over the year following surgery, fasting glucose and insulin values declined by 54% and 63%, respectively. Insulin sensitivity index increased 300% (P < .01), acute insulin response to glucose decreased 56% (P < .01), leading to a nearly 2-fold increase in the disposition index (P < .01). Consistent with improved β-cell function, the proinsulin to C-peptide ratio decreased by 21% (P < .01).
  
  
  CONCLUSIONS
  RYGB reduced body mass index and improved both insulin sensitivity and β-cell function in severely obese teens and young adults. These findings demonstrate that RYGB is associated with marked metabolic improvements in obese young people even as significant obesity persists.
  
  
  BACKGROUND
  ClinicalTrials.gov: NCT00360373.
authors.affiliation: Cincinnati Children's Hospital Medical Center, Cincinnati, OH. Electronic address: thomas.inge@cchmc.org.
authors.forename: Thomas H
authors.initials: TH
authors.lastname: Inge
authors.affiliation: University of Maryland School of Medicine, and Baltimore VA Medical Center Geriatric Research, Education and Clinical Center, Baltimore, MD.
authors.forename: Ronald L
authors.initials: RL
authors.lastname: Prigeon
authors.affiliation: Cincinnati Children's Hospital Medical Center, Cincinnati, OH.
authors.forename: Deborah A
authors.initials: DA
authors.lastname: Elder
authors.affiliation: Cincinnati Children's Hospital Medical Center, Cincinnati, OH.
authors.forename: Todd M
authors.initials: TM
authors.lastname: Jenkins
authors.affiliation: Department of Psychiatry, University of Cincinnati, Cincinnati, OH.
authors.forename: Robert M
authors.initials: RM
authors.lastname: Cohen
authors.affiliation: Cincinnati Children's Hospital Medical Center, Cincinnati, OH.
authors.forename: Stavra A
authors.initials: SA
authors.lastname: Xanthakos
authors.affiliation: Department of Psychiatry, University of Cincinnati, Cincinnati, OH.
authors.forename: Stephen C
authors.initials: SC
authors.lastname: Benoit
authors.affiliation: Cincinnati Children's Hospital Medical Center, Cincinnati, OH.
authors.forename: Lawrence M
authors.initials: LM
authors.lastname: Dolan
authors.affiliation: University of Colorado School of Medicine, Denver, CO.
authors.forename: Stephen R
authors.initials: SR
authors.lastname: Daniels
authors.affiliation: Division of Endocrinology, Diabetes and Metabolism, Duke University Medical Center, Durham, NC; Durham Veteran's Affairs Medical Center, Durham, NC.
authors.forename: David A
authors.initials: DA
authors.lastname: D'Alessio
mesh_terms: D000293:Adolescent; D001786:Blood Glucose / Q000032:analysis; D015992:Body Mass Index; D005215:Fasting; D005260:Female; D015390:Gastric Bypass; D005951:Glucose Tolerance Test; D006801:Humans; D007328:Insulin / Q000378:metabolism*; D007333:Insulin Resistance / Q000502:physiology*; D050417:Insulin-Secreting Cells / Q000378:metabolism*; D008137:Longitudinal Studies; D008297:Male; D063766:Pediatric Obesity / Q000378:metabolism* / Q000601:surgery*; D011446:Prospective Studies; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D001786:Blood Glucose; D007328:Insulin