None listed
Conditions
Brief summary
Following surgery for weight loss, the size of the stomach is considerably reduced and food passes through to the small intestines faster. When food passes through the small intestines, various ‘hormones’ that are thought to assist with weight loss enter the bloodstream. While this seems to be a useful effect, some may experience complications such as having a low blood sugar level (post-bariatric hypoglycaemia) or low blood pressure (post-prandial hypotension) after eating and we think this may happen due to increased production of these ‘hormones’. Currently, the treatment options for these conditions are limited. One of the more common types of weight loss surgery is called the Roux-en-Y gastric bypass. From previous studies, one particular hormone called glucagon-like peptide-1 has been consistently found to be elevated following a meal post-surgery and it is elevated to a greater extent in patients with post-bariatric hypoglycaemia. More recently, a newer surgical technique called the one anastomosis gastric bypass has been developed, however, we do not know whether the rate of passage of food and the hormonal changes occur to a similar extent as with the Roux-en-Y gastric bypass. This study will follow up on participants before and after surgery and we will analyse how hormonal profiles and how the speed of the passage of food changes. We will be able to compare the effects of Roux-en-Y gastric bypass and one anastomosis gastric bypass surgery. This understanding may assist in the development of newer therapies for post-bariatric hypoglycaemia and post-prandial hypotension.
Interventions
Participants will have undergo a gastric emptying study (via scintigraphy) and evaluation of glucoregulatory hormones pre-surgery, 6 and 12 months post bariatric surgery.
Prior to the 6 and 12 months post-bariatric surgery study:
Five days prior to the 6 and 12 months post-surgery study, participants will be connected to a blinded, external continuous blood glucose monitor (Dexcom G6) by a study investigator. The continuous blood glucose monitoring data will be collected on the study day.
At e
Participants will have undergo a gastric emptying study (via scintigraphy) and evaluation of glucoregulatory hormones pre-surgery, 6 and 12 months post bariatric surgery. Prior to the 6 and 12 months post-bariatric surgery study: Five days prior to the 6 and 12 months post-surgery study, participants will be connected to a blinded, external continuous blood glucose monitor (Dexcom G6) by a study investigator. The continuous blood glucose monitoring data will be collected on the study day. At each study: Participants will be given a solid meal consisting of 50 g beef patty (584 kJ) that has been radiolabelled with 20 MBq of technetium-99m sulphur colloid and a 150 ml glucose drink (50 g of glucose, 840 kJ) containing 7 MBq 67Ga-EDTA and 5 g 3-O-methylglucose (3-O-MG, Sigma Aldrich USA). The meal will be administered by a trained medical professional and will be consumed over 5 minutes at the research facility. The consumption of the meal will be supervised by the medical professional and the end of the meal will be designated t = 0. Following this, gastric emptying data will be acquired by scintigraphy in 1-min frames for the first 60 minutes, followed by 3-minute frames until t = 240 minutes. A region-of-interest that corresponds to the gastric pouch will be drawn to derive emptying curves and a cobalt marker will be placed over the skin in the region of the right iliac fossa of the participant to assist with the detection of the caecum. Data will be corrected for subject movement, radionuclide decay and at t = 300 min, the participant will drink 100 ml of water labelled with 4 MBq of technetium-99m sulphur colloid and a lateral image of the stomach will be acquired to derive correction factors for gamma ray attenuation. During the study, glucoregulatory hormones will be evaluated by venous blood samples taken prior to consumption of the meal and at t= 15, 30, 60, 90, 120, 180, 240 min. The overall duration of each study will be 5 hours.
Sponsors
The University of Adelaide
Eligibility
Sex/Gender
All
Age
18 Years to 75 Years
Healthy volunteers
No
Inclusion criteria
Males and females with or without diabetes who are planned to have Roux-en-Y gastric bypass or one anastomosis gastric bypass.
Exclusion criteria
• Use of any medication that may influence gastrointestinal motor function, body weight or appetite (glucagon-like peptide 1 receptor agonists, dipeptidyl peptidase 4 inhibitors, opiates, anticholinergics, levodopa, clonidine, nitrates, phosphodiesterase type 5 inhibitors, sumatriptan, metoclopramide, domperidone, prucalopride, or erythromycin) • Evidence of drug abuse, consumption of more than 20 g alcohol per day or an active smoking history • History of chronic gastrointestinal disease (inflammatory bowel disease, coeliac disease) or prior gastrointestinal surgery (other than other than bariatric surgery, uncomplicated appendicectomy or cholecystectomy) • History of epilepsy • History of severe respiratory, cardiovascular, hepatic and/or renal disease • Impaired renal (as assessed by calculated creatinine clearance < 90 mL/min), iron status, or liver function tests outside the following ranges: -Alanine aminotransferase (ALT) >3x ULN -Aspartate transaminase (AST) >3x ULN -Alkaline phosphatase (ALP) >3x ULN -Bilirubin >24 mmol/L -Ferritin <15 ng/mL (Females), <30 ng/mL (Males) -Haemoglobin <115 g/L (Females), <130 g/L (Males) • Donation of blood within the previous 3 months • Participation in any other research studies within the previous 3 months that requires blood sampling or exposure to radiation • Inability to give informed consent • Female participants who are pregnant or planning for pregnancy, or are lactating • Vegetarian
Outcome results
None listed