title: Effects of Gastric Bypass and Gastric Banding on Bone Remodeling in Obese Patients With Type 2 Diabetes.
abstract: BACKGROUND
  Roux-en-Y gastric bypass (RYGB) leads to high-turnover bone loss, but little is known about skeletal effects of laparoscopic adjustable gastric banding (LAGB) or mechanisms underlying bone loss after bariatric surgery.
  
  
  OBJECTIVE
  To evaluate effects of RYGB and LAGB on fasting and postprandial indices of bone remodeling.
  
  
  METHODS
  Ancillary investigation of a prospective study at 2 academic institutions.
  
  
  METHODS
  Obese adults aged 21-65 years with type 2 diabetes who underwent RYGB (n = 11) or LAGB (n = 8).
  
  
  RESULTS
  Serum C-terminal telopeptide (CTX), procollagen type 1 N-terminal propeptide (P1NP), and PTH were measured during a mixed meal tolerance test at baseline, 10 days and 1 year after surgery. Changes in 25-hydroxyvitamin D, polypeptide YY (PYY), glucagon-like peptide-1, glucose-dependent insulinotropic peptide, and insulin were also assessed.
  
  
  RESULTS
  Fasting CTX increased 10 days after RYGB but not LAGB (+69 ± 23% vs +12±12%, P < .001), despite comparable weight loss at that time. By 1 year, fasting CTX and P1NP increased more after RYGB than LAGB (CTX +221 ± 60% vs +15 ± 6%, P<0.001; P1NP +93 ± 25% vs -9 ± 10%, P < .001) and weight loss was greater with RYGB. Changes in CTX were independent of PTH and 25-hydroxyvitamin D but were associated with increases in fasting PYY. Postprandial suppression of CTX was more pronounced after RYGB than LAGB at 10 days and 1 year postoperatively.
  
  
  CONCLUSIONS
  RYGB is accompanied by early increases in fasting indices of bone remodeling, independent of weight loss or changes in PTH or 25-hydroxyvitamin D. LAGB did not affect bone markers. PYY and other enterohormonal signals may play a role in RYGB-specific skeletal changes.
authors.affiliation: Endocrine Unit (E.W.Y.), Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114; Research Division (M.W., S.-A.D., K.F., A.B.G.), Joslin Diabetes Center, Harvard Medical School, Boston, Massachusetts 02215; Division of Endocrinology (D.C.S., A.B.G., F.H.), Diabetes, and Hypertension, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115; Novo Nordisk Foundation Center for Basic Metabolic Research and Department of Biomedical Sciences (J.J.H.), University of Copenhagen, Denmark; and Center for Metabolic and Bariatric Surgery (A.V.), Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115.
authors.forename: Elaine W
authors.initials: EW
authors.lastname: Yu
authors.affiliation: Endocrine Unit (E.W.Y.), Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114; Research Division (M.W., S.-A.D., K.F., A.B.G.), Joslin Diabetes Center, Harvard Medical School, Boston, Massachusetts 02215; Division of Endocrinology (D.C.S., A.B.G., F.H.), Diabetes, and Hypertension, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115; Novo Nordisk Foundation Center for Basic Metabolic Research and Department of Biomedical Sciences (J.J.H.), University of Copenhagen, Denmark; and Center for Metabolic and Bariatric Surgery (A.V.), Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115.
authors.forename: Marlene
authors.initials: M
authors.lastname: Wewalka
authors.affiliation: Endocrine Unit (E.W.Y.), Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114; Research Division (M.W., S.-A.D., K.F., A.B.G.), Joslin Diabetes Center, Harvard Medical School, Boston, Massachusetts 02215; Division of Endocrinology (D.C.S., A.B.G., F.H.), Diabetes, and Hypertension, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115; Novo Nordisk Foundation Center for Basic Metabolic Research and Department of Biomedical Sciences (J.J.H.), University of Copenhagen, Denmark; and Center for Metabolic and Bariatric Surgery (A.V.), Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115.
authors.forename: Su-Ann
authors.initials: SA
authors.lastname: Ding
authors.affiliation: Endocrine Unit (E.W.Y.), Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114; Research Division (M.W., S.-A.D., K.F., A.B.G.), Joslin Diabetes Center, Harvard Medical School, Boston, Massachusetts 02215; Division of Endocrinology (D.C.S., A.B.G., F.H.), Diabetes, and Hypertension, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115; Novo Nordisk Foundation Center for Basic Metabolic Research and Department of Biomedical Sciences (J.J.H.), University of Copenhagen, Denmark; and Center for Metabolic and Bariatric Surgery (A.V.), Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115.
authors.forename: Donald C
authors.initials: DC
authors.lastname: Simonson
authors.affiliation: Endocrine Unit (E.W.Y.), Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114; Research Division (M.W., S.-A.D., K.F., A.B.G.), Joslin Diabetes Center, Harvard Medical School, Boston, Massachusetts 02215; Division of Endocrinology (D.C.S., A.B.G., F.H.), Diabetes, and Hypertension, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115; Novo Nordisk Foundation Center for Basic Metabolic Research and Department of Biomedical Sciences (J.J.H.), University of Copenhagen, Denmark; and Center for Metabolic and Bariatric Surgery (A.V.), Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115.
authors.forename: Kathleen
authors.initials: K
authors.lastname: Foster
authors.affiliation: Endocrine Unit (E.W.Y.), Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114; Research Division (M.W., S.-A.D., K.F., A.B.G.), Joslin Diabetes Center, Harvard Medical School, Boston, Massachusetts 02215; Division of Endocrinology (D.C.S., A.B.G., F.H.), Diabetes, and Hypertension, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115; Novo Nordisk Foundation Center for Basic Metabolic Research and Department of Biomedical Sciences (J.J.H.), University of Copenhagen, Denmark; and Center for Metabolic and Bariatric Surgery (A.V.), Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115.
authors.forename: Jens J
authors.initials: JJ
authors.lastname: Holst
authors.affiliation: Endocrine Unit (E.W.Y.), Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114; Research Division (M.W., S.-A.D., K.F., A.B.G.), Joslin Diabetes Center, Harvard Medical School, Boston, Massachusetts 02215; Division of Endocrinology (D.C.S., A.B.G., F.H.), Diabetes, and Hypertension, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115; Novo Nordisk Foundation Center for Basic Metabolic Research and Department of Biomedical Sciences (J.J.H.), University of Copenhagen, Denmark; and Center for Metabolic and Bariatric Surgery (A.V.), Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115.
authors.forename: Ashley
authors.initials: A
authors.lastname: Vernon
authors.affiliation: Endocrine Unit (E.W.Y.), Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114; Research Division (M.W., S.-A.D., K.F., A.B.G.), Joslin Diabetes Center, Harvard Medical School, Boston, Massachusetts 02215; Division of Endocrinology (D.C.S., A.B.G., F.H.), Diabetes, and Hypertension, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115; Novo Nordisk Foundation Center for Basic Metabolic Research and Department of Biomedical Sciences (J.J.H.), University of Copenhagen, Denmark; and Center for Metabolic and Bariatric Surgery (A.V.), Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115.
authors.forename: Allison B
authors.initials: AB
authors.lastname: Goldfine
authors.affiliation: Endocrine Unit (E.W.Y.), Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114; Research Division (M.W., S.-A.D., K.F., A.B.G.), Joslin Diabetes Center, Harvard Medical School, Boston, Massachusetts 02215; Division of Endocrinology (D.C.S., A.B.G., F.H.), Diabetes, and Hypertension, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115; Novo Nordisk Foundation Center for Basic Metabolic Research and Department of Biomedical Sciences (J.J.H.), University of Copenhagen, Denmark; and Center for Metabolic and Bariatric Surgery (A.V.), Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115.
authors.forename: Florencia
authors.initials: F
authors.lastname: Halperin
mesh_terms: D000328:Adult; D000368:Aged; D050110:Bariatric Surgery; D015415:Biomarkers; D016723:Bone Remodeling; D001842:Bone and Bones / Q000378:metabolism; D003924:Diabetes Mellitus, Type 2 / Q000378:metabolism* / Q000473:pathology / Q000601:surgery*; D005260:Female; D015390:Gastric Bypass; D006801:Humans; D006887:Hydroxycholecalciferols / Q000097:blood; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000378:metabolism* / Q000473:pathology / Q000601:surgery*; D010281:Parathyroid Hormone / Q000097:blood; D019518:Postprandial Period; D011446:Prospective Studies; D015431:Weight Loss; D055815:Young Adult
chemical_list: D015415:Biomarkers; D006887:Hydroxycholecalciferols; D010281:Parathyroid Hormone