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Updated: May 6, 2026

Roux-en-Y Gastric Bypass Operation in Rats
Published on: June 11, 2012
Bone health up to five years after Roux-en-Y gastric bypass: a cross-sectional study during the COVID-19 pandemic
Alexandre Naegele de Oliveira1, Taís Daiene Russo Hortencio1, Daniela Vicinansa Monaco Ferreira1
1Instituto de Pesquisa São Leopoldo Mandic - Faculdade São Leopoldo Mandic - Campinas (SP) - Brazil.
Purpose:
To evaluate bone health in obese patients undergoing surgery using the Roux-en-Y gastric bypass (RYGB) technique.
Methods:
In a sample of 22 obese patients undergoing RYGB surgery, evaluation of bone densitometry (BD) and plasma levels of calcium, phosphorus, magnesium, vitamin D (VITD), parathyroid hormone (PTH), alkaline phosphatase, and albumin was performed.
Results:
Signs of potential changes in calcification were detected in plasma tests, expressed as a decrease in VITD (46.4%) and an increase in PTH (50%). Three patients presented with bone framework damage. BD was unequivocally altered in three patients. A decrease in bone density was observed in 14 and 15 patients in the lumbar and femoral regions, respectively.
Conclusion:
Although PTH and VITD dosages did not show a direct correlation with BD, it was observed that approximately half of the patients had altered dosages of these hormones up to five years after surgery, and there was damage to the bone health expressed by BD. Loss to follow-up may have contributed to the increased risk of developing metabolic bone disease.
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