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Updated: Apr 10, 2026

Roux-en-Y Gastric Bypass Operation in Rats
Published on: June 11, 2012
Magnitude and durability of hormonal adaptations after bariatric surgery: a dose response meta-analysis
Mohamed Badie Ahmed1, Youssuf Khanafer2, Mohamed A Abdelsalam2
1Department of Population Medicine, College of Medicine, QU Health, Qatar University, Doha, Qatar; Plastic Surgery Department, Hamad General Hospital, Hamad Medical Corporation, Doha, Qatar.
Background:
Bariatric surgery induces metabolic improvements that extend beyond weight loss, yet the hormonal dynamic underlying these effects remain incompletely characterized. Previous meta-analyses have relied on static comparisons of hormone levels, limiting insight into the temporal dynamics of endocrine adaptation.
Objectives:
To quantify the magnitude and durability of hormonal changes following bariatric surgery and to elucidate how these shifts may refine procedure selection and identify key metabolic pathways.
Setting:
Not applicable, as this dose-response meta-analysis (DRMA) synthesized data from previously published studies.
Methods:
We conducted a DRMA of 59 studies to model postoperative trajectories of six hormones: glucagon-like peptide-1 (GLP-1), gastric inhibitory polypeptide (GIP), PYY, leptin, adiponectin, and ghrelin after Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG).
Results:
RYGB led to sustained increases in GLP-1 and PYY and a steady decline in GIP, while SG produced durable suppression of ghrelin and an earlier rise in adiponectin. Leptin declined after both procedures, with a greater drop post-RYGB. Several hormones exhibited nonlinear trends, highlighting the importance of evaluating the durability and timing of postoperative hormonal responses.
Conclusion:
RYGB and SG elicit distinct and durable postoperative hormonal trajectories over time, reflecting divergent physiological mechanisms. These profiles may help guide procedure selection according to metabolic characteristics and support the use of endocrine markers to improve long-term outcomes.
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