Increase of bone resorption and the parathyroid hormone in postmenopausal women in the long-term after Roux-en-Y gastric bypass.
BACKGROUND
The effects of Roux-en-Y Gastric Bypass (RYGB) on bone in the long-term remains unclear. We assessed bone metabolism and bone mineral density (BMD) 1 to 5 years after RYGB.


METHODS
We designed a retrospective cohort study in 26 postmenopausal women (58.0+/-3.9 years old) with RYGB 3.5+/-1.1 years before (body mass index (BMI) 29.5+/-3.8 kg/m2, presurgery 43.6+/-5.5 kg/m2) and 26 nonoperated women (57.5+/-4.7 years old, BMI 29.2+/-4.1 kg/m2) matched by age and BMI. The main measures were BMD, serum carboxy telopeptide (CTx), total alkaline phosphatases (ALP), parathyroid hormone (PTH), 25-hydroxyvitamin D (25OHD), and ghrelin.


RESULTS
RYGB group, compared to nonoperated women, had higher CTx (0.71+/-0.21 vs. 0.43+/-0.15 ng/ml; P<0.01) and PTH (68.3+/-35 vs. 49.4+/-16 pg/ml; P=0.02). There were no differences between RYGB and nonoperated women in: calcium and vitamin D intake (759+/-457 vs. 705+/-460 mg/day; 176+/-160 vs. 111+/-86 UI/day), ghrelin (763+/-336 vs. 621+/-274 pg/ml), ALP (101+/-22 vs. 94+/-25 UI/l), 25OHD (18.8+/-7.6 vs. 17.4 +/- 5.9 ng/ml), lumbar spine BMD (1.059+/-0.32 vs. 1.071+/-0.207 g/cm2), or femoral neck BMD (0.892+/-0.109 vs. 0.934+/-1.1 g/cm2).


CONCLUSIONS
RYGB is associated to high bone resorption and hyperparathyroidism prevalence in postmenopausal women in the long-term. This occurs independently of the intake of calcium, vitamin D status, or ghrelin and does not seem to affect BMD after RYGB.
Valderas
Juan P
JP
Department of Nutrition, Diabetes, and Metabolism, Faculty of Medicine, Pontificia Universidad Católica de Chile, Marcoleta 367, 6510260, Santiago, Chile. jpvalder@uc.cl
Velasco
Soledad
S
Solari
Sandra
S
Liberona
Yessica
Y
Viviani
Paola
P
Maiz
Alberto
A
Escalona
Alex
A
González
Gilberto
G
D000469:Alkaline Phosphatase / Q000097:blood; D015519:Bone Density; D001862:Bone Resorption / Q000378:metabolism*; D002136:Calcium, Dietary / Q000008:administration & dosage; D024042:Collagen Type I; D005260:Female; D005500:Follow-Up Studies; D015390:Gastric Bypass; D054439:Ghrelin / Q000097:blood; D006801:Humans; D008875:Middle Aged; D009765:Obesity / Q000601:surgery; D015663:Osteoporosis, Postmenopausal / Q000209:etiology* / Q000378:metabolism / Q000517:prevention & control; D010281:Parathyroid Hormone / Q000097:blood*; D010446:Peptide Fragments / Q000097:blood; D010455:Peptides; D017698:Postmenopause; D011183:Postoperative Complications; D011347:Procollagen / Q000097:blood; D012189:Retrospective Studies; D014807:Vitamin D / Q000008:administration & dosage / Q000031:analogs & derivatives / Q000097:blood; D016387:Women's Health
D002136:Calcium, Dietary; D024042:Collagen Type I; D054439:Ghrelin; D010281:Parathyroid Hormone; D010446:Peptide Fragments; D010455:Peptides; D011347:Procollagen; C052929:collagen type I trimeric cross-linked peptide; D014807:Vitamin D; C104450:25-hydroxyvitamin D; D000469:Alkaline Phosphatase