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Updated: Jun 9, 2026

Roux-en-Y Gastric Bypass Operation in Rats
Published on: June 11, 2012
Determinants of hyperhomocysteinemia after gastric bypass surgery in obese subjects
Séverine Ledoux1, Muriel Coupaye, Catherine Bogard
1Explorations Fonctionnelles, Centre de Référence de l'Obésité, Hôpital Louis Mourier, AP-HP, 178 rue des Renouillers, 92700 Colombes, France. severine.ledoux@lmr.aphp.fr
Background:
Effectiveness of gastric bypass (GBP) on reduction of vascular risk factors is well established, but GBP induces nutritional deficits that could reduce the cardiovascular benefit of weight loss. Particularly, hyperhomocysteinemia, now clearly identified as a vascular risk factor, has been described after GBP. The aim of this study was to clarify the factors associated with increased homocysteine concentration after GBP.
Methods:
Homocysteine concentration and multiple nutritional parameters were measured in 213 consecutive subjects. One hundred and eight subjects were studied before surgery (control (CT)), 115 one to 6 years after GBP, and 41 both before and 6 months after GBP.
Results:
Homocysteine concentration did not differ before and after GBP (9.1 ± 3.2 vs 8.6 ± 3.4 μmol/l), but 94% of subjects had been supplemented with a multivitamin preparation after surgery. The nutritional parameters best correlated with homocysteine concentration both before and after GBP were folate and creatinine concentrations (p < 0.0001). In contrast, vitamin B12 and metabolic parameters (including glucose, insulin, lipids and C-reactive protein) were not associated with homocysteine concentration. After GBP, homocysteine concentration was significantly lower in subjects taking a multivitamin supplementation containing a high dose of folate than those who did not (7.7 ± 2.8 vs 10.1 ± 3.9 μmol/l, p < 0.0001).
Conclusions:
The main determinants of homocysteine concentration identified in this study are folate and serum creatinine. Multivitamin supplementation with a high dose of folate prevents hyperhomocysteinemia after GBP.
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