The gut hormone response following Roux-en-Y gastric bypass: cross-sectional and prospective study.
BACKGROUND
Bariatric surgery is the most effective treatment option for obesity, and gut hormones are implicated in the reduction of appetite and weight after Roux-en-Y gastric bypass. Although there is increasing interest in the gut hormone changes after gastric bypass, the long-term changes have not been fully elucidated.


METHODS
Thirty-four participants were studied cross-sectionally at four different time points, pre-operatively (n = 17) and 12 (n = 6), 18 (n = 5) and 24 months (n = 6) after laparoscopic Roux-en-Y gastric bypass. Another group of patients (n = 6) were studied prospectively (18-24 months). All participants were given a standard 400 kcal meal after a 12-h fast, and plasma levels of peptide YY (PYY) and glucagon-like peptide-1 (GLP-1) were correlated with changes in appetite over 3 h using visual analogue scores.


RESULTS
The post-operative groups at 12, 18 and 24 months had a higher post-prandial PYY response compared to pre-operative (p < 0.05). This finding was confirmed in the prospective study at 18 and 24 months. There was a trend for increasing GLP-1 response at 18 and 24 months, but this did not reach statistical significance (p = 0.189) in the prospective study. Satiety was significantly reduced in the post-operative groups at 12, 18 and 24 months compared to pre-operative levels (p < 0.05).


CONCLUSIONS
Roux-en-Y gastric bypass causes an enhanced gut hormone response and increased satiety following a meal. This response is sustained over a 24-month period and may partly explain why weight loss is maintained.
Pournaras
Dimitrios J
DJ
Department of Bariatric Surgery, Musgrove Park Hospital, Taunton, Somerset TA1 5DA, UK.
Osborne
Alan
A
Hawkins
Simon C
SC
Mahon
David
D
Ghatei
Mohammad A
MA
Bloom
Steve R
SR
Welbourn
Richard
R
le Roux
Carel W
CW
D000328:Adult; D003430:Cross-Sectional Studies; D005260:Female; D015390:Gastric Bypass; D052216:Glucagon-Like Peptide 1 / Q000097:blood*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009767:Obesity, Morbid / Q000097:blood* / Q000601:surgery; D019894:Peptide YY / Q000097:blood*; D011184:Postoperative Period; D011446:Prospective Studies; D012528:Satiety Response / Q000502:physiology; D015431:Weight Loss / Q000502:physiology
D019894:Peptide YY; D052216:Glucagon-Like Peptide 1