Weight Loss and Changes in Salivary Ghrelin and Adiponectin: Comparison Between Sleeve Gastrectomy and Roux-en-Y Gastric Bypass and Gastric Banding

Weight loss is associated with increased levels of adiponectin with a greater increase observed following Roux-en-Y gastric bypass (RYGB) compared to restrictive procedures. However, currently there are no data on changes in adiponectin following laparoscopic sleeve gastrectomy (LSG). Ghrelin was reported to be also produced by the salivary glands. There are also no data available regarding its changes following bariatric surgery. The present study examined weight loss, and salivary ghrelin and HMW adiponectin levels in 43 morbidly obese subjects undergoing three different types of bariatric surgery. We found that weight loss following LSG is superior to laparoscopic adjustable gastric banding (LAGB) and comparable to RYGB at 12 months after surgery. Although blood glucose decreased similarly following all three procedures, fasting insulin continuously declined only in LSG and RYGB patients. Changes in both fasting and postprandial salivary ghrelin greatly varied between all three procedures with no similarities to changes in serum ghrelin reported in the literature. HMW adiponectin significantly increased following LSG, and this increase was more marked than in LAGB patients and almost identical compared to RYGB. Weight loss following LSG is comparable to RYGB in the short term. Changes in HMW adiponectin are comparable following LSG and RYGB which may further contribute to the successful results after LSG. Furthermore, the results of the present study support the hypothesis that there is an autonomous production of ghrelin in salivary glands irrespective of nutritional status and weight loss.