View clinical trials related to Gastric Bypass.
Filter by:In many studies, gastric bypass surgery led to total remission of type 2 diabetes (T2DM) as early as 1 - 2 days after surgery before any real weight loss has occurred. This suggests that the remission of the T2DM is due to the direct effect of the operation, more than the secondary effect of the weight loss. The reasons for the major effect on the glucose metabolism after gastric bypass surgery are still unaccounted for. The aim of this project will be to unveil some of the mechanisms that explain the effect of gastric bypass surgery on the glucose metabolism. Further more to find a better way of testing patients that have just undergone gastric bypass surgery. It is not possible to test patients who have just undergone gastric bypass surgery with normal oral glucose tolerance test (OGTT) and a normal meal, because patients can only take in fluid and a normal OGTT will often lead to dumping. Instead we will try to modify these tests - OGTT with lower glucose level and meal-testing with a protein drink. The hypothesis of the study is that the investigators can see changes in different hormones and adipokines before and after surgery, even with modified OGTT and meal testing. The project will consist of clinical trials on patients without T2DM that will undergo gastric bypass surgery. The studies will take place before and within the first week after surgery. The investigators will measure different hormones and adipokines after OGTT and a meal with a protein drink. The investigators expect to see significant changes in some of the analyses after the operation in patients undergoing gastric bypass.
Obesity affects more than 43 million Americans and is associated with an increased incidence of heart failure, sudden death, and cardiovascular death. We have shown that increasing obesity is independently associated with potentially detrimental LV structural and functional, and metabolic changes. Thus in order to increase our understanding of the effect of obesity on the heart, we wish to study the effect of significant weight loss on these parameters.
The aim of this study is to demonstrate the influence of peri-operative nutrition on the preservation of lean body mass after gastric bypass, as well as it's influence on postoperative complications.
This study, conducted at the NIH Clinical Research Unit (CRU) at the Phoenix Indian Medical Center, will compare the effects of two methods of bariatric surgery, the adjustable BAND and Roux-en-Y gastric bypass, on insulin. Bariatric surgery is a treatment for achieving and maintaining weight loss. The study will look at how this surgery might improve how insulin (a hormone important for regulating blood sugar levels) is made and works in the body and the possible role of changes in other hormones produced by the gut (stomach and intestines). People between 18 and 50 years of age who are scheduled to have either laparoscopic adjustable BAND or Roux-en-Y gastric bypass surgery may be eligible for this study. Candidates are screened about 4 to 6 weeks before their surgery with a medical history, blood tests and an oral glucose tolerance test for diabetes. Participants spend 4 days at the CRU or 2 days overnight and an out-patient visit approximately 4 to 6 weeks before their surgery and again 3 to 6 weeks after their surgery. They return for a 4-6 hour visit at the CRU at 6 months, 1 and 2 years after surgery and for half-day outpatient visits at 3, 4 and 5 years after surgery for the following procedures: - Blood and urine tests, including a pregnancy test for women. (4-day and 2-day admissions and years, 3, 4 and 5) - DEXA, an x-ray scan to determine body fat content. (4-day and 2-day admissions and years, 3, 4 and 5) - MRI scan to measure fat tissue in the abdomen. (4-day and 2-day admissions and years, 3, 4 and 5) - Intravenous (I.V.) glucose tolerance test for risk of obesity and diabetes. A sugar solution is given through a needle in a vein of one arm and blood samples are drawn through another needle in a vein in the other arm. (4-day admissions) - Meal test to measure blood sugar and insulin and gut hormone levels after a meal. After an I.V. line is placed in an arm vein, the subject eats breakfast over 20 minutes. Blood samples are collected halfway through the meal, at the end of the meal, and at 15, 30, 60, 90, 120 and 180 minutes after completing the meal. Subjects fill out questionnaires on feelings of hunger and fullness before, during and after the meal test. (4-day and 2-day admissions) - Glucose clamp test to measure the effect on the body of insulin given through a vein. An I.V line is placed in a vein in the arm and in a vein of the hand on the other side of the body. While insulin is infused through one I.V., blood sugar levels are checked every 5 minutes and a sugar solution is given into a vein as needed. A radioactive sugar is also infused very slowly over 4 hours to determine how much sugar the body produces by itself. (4-day admissions)
MIDAS involves an assessment of glucose levels obtained before and after bariatric surgery. There are two different procedural tests involved; an oral glucose tolerance test (mixed meal) and a hyperglycemic clamp test. Two tests are performed preoperatively and five more are performed postoperatively for a one year period. The associated labwork drawn with the mixed meal and clamp tests are demonstrating changes in glucose, insulin and gut hormone levels.