Suboptimal Weight Loss 13 Years After Roux-en-Y Gastric Bypass Is Associated with Blunted Appetite Response

Area of Science:

• Endocrinology
• Gastroenterology
• Bariatric Surgery Outcomes

Background:

• Bariatric surgery, like Roux-en-Y gastric bypass (RYGB), is effective for sustained weight loss.
• A significant portion of patients experience suboptimal weight loss (SWL) post-surgery.
• The homeostatic appetite control system is implicated in weight loss outcomes.

Purpose of the Study:

• To compare plasma gastrointestinal hormone concentrations and appetite ratings in patients with SWL versus optimal weight loss (OWL) after RYGB.
• To investigate potential mechanisms underlying SWL in the context of appetite regulation.

Main Methods:

• Compared 50 RYGB patients (SWL or OWL >13 years post-op) with 25 non-surgical controls.
• Assessed plasma levels of acylated ghrelin (AG), GLP-1, PYY, and CCK.
• Measured subjective appetite ratings (hunger, fullness, DTE, PFC) in fasting and postprandial states.

Main Results:

• OWL patients had higher basal AG and GLP-1, and lower AG postprandial response compared to SWL and controls.
• Both RYGB groups showed higher PYY and CCK postprandial responses than controls.
• Lower prospective food consumption (PFC) was observed in OWL vs. SWL; total weight loss correlated positively with GLP-1 and negatively with desire to eat (DTE) and PFC.

Conclusions:

• Suboptimal weight loss (>13 years post-RYGB) is associated with reduced basal ghrelin levels.
• A diminished satiety response to meals is linked to SWL after bariatric surgery.
• Further research is needed to establish causality between these hormonal and appetite changes and SWL.