Surgery is currently the most effective way to obtain a controlled weight reduction in morbidly obese patients.
|All changes were related to a reduction in BMI.|
|Journal of Clinical Endocrinology and Metabolism|
Roux-en-Y gastric bypass (RYGBP) surgery is effective and it is used worldwide. However, its mechanism of action is unclear.
In this study, researchers from Sweden assessed the effect of RYGBP on ghrelin, insulin, adiponectin, and leptin levels in 66 obese subjects.
The patients' mean weight was 127 kg and their mean body mass index (BMI) was 45 kg/m2.
The team also compared ghrelin levels in 10 non-operated and 10 operated obese, BMI-matched women.
The research team found that RYGBP resulted in 22% weight loss at 6 months after surgery, and 30% weight loss at 12 months.
In addition, ghrelin increased by 44% and 62%, at 6 and 12 months, respectively. An increase was also observed for adiponectin by 36% and 98%.
However, the team determined that insulin declined by 57% and 62% and leptin by 60% and 64%.
The team found that all changes were related to a reduction in BMI.
They found that ghrelin and insulin were inversely correlated at all time points, independent of any change in BMI. This pattern was also found for changes in peptides at 12 months.
Dr Camilla Holdstock's team concluded, "No evidence for RYGBP surgery per se having an effect on ghrelin levels, independent of weight loss, was obtained".
"The profound changes in the regulatory peptides are likely to reflect the new state of energy balance achieved".
"A close inverse association between ghrelin and insulin was observed, supporting an important role for ghrelin in glucose homeostasis".