Impact of gastric banding on plasma adiponectin levels

Background: Several endocrine abnormalities are reported in obesity. In an earlier study, we found that the changes in BMI following laparoscopic adjustable gastric banding (LAGB) were associated with changes in hormone profiles such as insulin and proinsulin. In the current study, we explored the changes in plasma adiponectin levels in morbidly obese subjects who lost abundant weight following LAGB. Methods: 23 adult morbidly obese patients (15 females), aged 21-56 years, were studied. Blood samples were collected before, and 6 and 14 months after LAGB. The plasma adiponectin levels were determined by commercial kit (B-Bridge International, Inc). Statistical analysis was based on one-way repeated measures ANOVA, followed by Student-Newman-Keuls post-hoc test. Regression model was used to look for predictors of adiponectin change after LAGB. Results: Mean BMI before surgery was 46.04 +/- 4.44 kg/m(2), and decreased significantly by 18% 6 months after surgery to 37.67 +/- 4.47 kg/m(2). BMI further decreased by 32% 14 months after surgery to a mean of 31.30 +/- 4.65 kg/m(2) (P=.000). The mean adiponectin level before surgery was 3997 +/- 1766 mu g/ml, and increased significantly by 16% to 4763 +/- 1776 mu g/ml 6 months after surgery, and to 6336 +/- 3292 mu g/ml (37%) 14 months after surgery. Although BMI persistently decreased, while adiponectin persistently increased, BMI did not correlate with adiponectin. Conclusion: In morbidly obese patients who underwent LAGB, adiponectin levels persistently increased, probably due to the reduction of visceral fat mass. Adiponectin plasma increase was correlated with proinsulin levels prior to the surgery. The interaction between adiponectin, proinsulin and BMI change in morbid obesity merits further investigation.