UNIVERSITY OF CALIFORNIA SAN FRANCISCO
GENERAL CLINICAL RESEARCH CENTER
CONSENT TO PARTICIPATE IN A RESEARCH STUDY
Insulin Sensitivity after Gastric Bypass, Adjustable Gastric Banding and Caloric Restriction in Persons with Morbid Obesity: A Stratified, Randomized, Controlled Pilot Trial.
This is a medical research study. Your study doctor, Guilherme M Campos, MD, or one of his associates will explain this study to you. Medical research studies include only people who voluntarily choose to take part. Take your time to make your decision about participation. You may discuss your decision with your family and friends and with your health care team. If you have any questions, ask your study doctor.
You are being asked to take part in this study because you have qualified to undergo either laparoscopic Roux-en-Y gastric bypass or laparoscopic adjustable gastric banding at UCSF. Being in this study does not affect the type of surgical procedure you will undergo.
Why is this study being done?
This study is designed to determine how gastric bypass or gastric banding surgery affects diabetes and insulin resistance, which are very common problems in obese individuals; and to see if the improvements in diabetes following surgery are better than can be achieved by losing weight with diet alone.
How many people will take part in this study?
Thirty people will take part in this study over a period of about two years. Fifteen will be people who choose gastric bypass surgery and the other fifteen will be people who choose gastric banding surgery.
What will happen if I take part in this research study?
If you agree to participate and are eligible, the following will happen:
You will be ‘randomized’ to enter the “immediate surgery group” or the “diet group,” which will subsequently undergo surgery. Randomization means that you are put into a group by chance (like flipping a coin). Neither you nor your doctor can choose the group (immediate surgery vs. diet followed by surgery) you will be in. You will have a 2:1 chance of being randomized to undergo immediate surgery. In other words, of 15 participants who are candidates for gastric bypass, 10 will undergo immediate gastric bypass surgery and 5 will receive a diet followed by gastric bypass surgery. Likewise, of the 15 participants who are candidates for banding, 10 will undergo immediate banding surgery and 5 will receive a diet followed by banding surgery.
It is important to underscore that participating in the study does not speed up or delay your surgery date and you will have the surgical procedure (either gastric bypass or gastric banding) that you agreed upon with your surgeon. If you are randomized to the diet group, your surgery (either gastric bypass or gastric banding) will be scheduled independently of this study protocol and we will adjust the study tests to be performed accordingly. Likewise, your group assignment does not affect the total number of tests that will be performed.
Regardless of which group your are assigned to, you will start the study by being admitted to the General Clinical Research Center at the San Francisco General Hospital (SFGH-GCRC) for about one and a half day to undergo a set of baseline tests that are described below under the Section " What tests will be done?". The GCRC is a research ward at SFGH. While you are in the GCRC, you will not be required to stay in bed the whole time, and you will be allowed to leave the ward briefly if you want to go outside for a walk. Certain tests will be performed each morning before you may eat, and on some mornings you will have to remain in bed for several hours.
Immediate surgery groups (gastric bypass or gastric banding): After completing the baseline set of tests, you will be discharged from the GCRC and admitted the next day to the UCSF Moffitt-Long Hospital for your chosen operation. When you are considered ready for discharge from the hospital (usually on post-operative day 1 or 2), you will be discharged and you will be outpatient for 14-days. During these 14 days you will receive a standardized commercial liquid diet regimen that consists of an 800 kcal/d. This liquid diet is similar to that recommended to all persons after surgery. The diet will provide all of your nutritional needs and is designed to have extra protein and vitamins that you will need after surgery. Please note that the standardized diet regimen consists entirely of a liquid diet, is portion-controlled, calorically precise, and has been shown to help people stick to their diet plan. The benefits include high quality, complete nutrition, pre-portioned and calorie-controlled servings, quick and simple preparation and enhanced ability to stick with the diet because no food choices are made. You will be provided with pre-packaged servings and instructed to follow a specific feeding schedule. You will be asked to consume all of the diet that is provided to you, and you will not be allowed to consume any other foods. You can drink as much plain water and noncarbonated diet drinks as you need. Additionally, you will meet with the dietitian prior to the start of the study for individual instructions regarding the diet and counseling on specific concerns they might have. During the 14 day period, you will be asked to fill daily logs of all food, water and drinks ingested, and you will be contacted every other day by the Bariatric Clinical Research Fellow to provide continued guidance and medical monitoring of the progress, health, and well-being throughout the course of treatment. Furthermore, alternate-day phone calls from the research dietitian will allow the assessment of your compliance. You will visit the GCRC on days 1 and 8 of the diet phase to be weighed on the same scale, to receive the diet servings and review the diet diary forms. Communication with the PI (Dr. Campos, Pager: 443-7353) or Co-I (Bariatric Clinical Research Fellow, Pager: 443-8713) is provided 24 hours a day.
After those 14 days, all of the tests performed before your surgery will be repeated over a one and a half-day period at the GCRC. During this one and a half day you will continue to receive the same 800 kcal/d liquid diet provided by the nutritional service at the GCRC. You will then be discharged to home to resume your normal activities. After 6 months you will be readmitted to the GCRC for about one and a half-day period to take one final set of tests. You are then done with this study.
Diet Group: After the initial baseline evaluation (that is the same as described for the persons randomly selected for the immediate surgery groups) you will be discharged and you will be outpatient for 14-days and immediately start the standardized diet regimen. This consists of an 800 kcal/d liquid diet. Please note that the standardized diet regimen consists entirely of a liquid diet, is portion-controlled, calorically precise, nutritionally complete, and has been shown to help people stick to their diet plan. The benefits include high quality, complete nutrition, pre-portioned and calorie-controlled servings, quick and simple preparation and enhanced ability to stick with the diet because no food choices are made. You will be provided with pre-packaged servings and instructed to follow a specific feeding schedule. You will be asked to consume all of the diet that is provided to you, and you will not be allowed to consume any other foods. You can drink as much plain water and noncarbonated diet drinks as you need. Additionally, you will meet with the dietitian prior to the start of the study for individual instructions regarding the diet and counseling on specific concerns they might have. During the 14 day period, you will be asked to fill daily logs of all food, water and drinks ingested, and you will be contacted every other day by the Bariatric Clinical Research Fellow to provide continued guidance and medical monitoring of the progress, health, and well-being throughout the course of treatment. Furthermore, alternate-day phone calls from the research dietitian will allow the assessment of your compliance. You will visit the GCRC on days 1 and 8 of the diet phase to be weighed on the same scale, to receive the diet servings and review the diet diary forms. Communication with the PI (Dr. Campos, Pager: 443-7353) or Co-I (Bariatric Clinical Research Fellow, Pager: 443-8713) is provided 24 hours a day.
Fourteen days after the diet period, you will again be admitted for about one and a half day-period to the GCRC and will repeat all of the procedures outlined under Baseline Evaluation (see above). After this one and a half day you will be admitted to the UCSF Moffitt-Long Hospital for your chosen operation. After your surgery you will be discharged to home from the hospital to resume your normal activities. After 6 months you will be readmitted to the GCRC for about one and a half-day period to repeat all of the tests done at baseline. You are then done with this study.
What tests will be done?
· Medical Chart Review and Physical Exam: Your medical chart will be reviewed by the study doctors and you will have a routine physical examination as part of your standard medical care.
· Weight: While you are in the GCRC your weight will be measured every morning. This is being performed as part of this study for research purposes only.
· Baseline Blood Drawing (Venipuncture): You will be asked to give a blood sample for a set of initial laboratory tests. Approximately 4 tablespoons of blood will be drawn by inserting a needle into a vein in your arm. The specific tests to be performed are the following: hormones (leptin, adiponectin), glucose, lipids (triglycerides, LDL cholesterol), albumin and pre-albumin. In addition, small samples of blood will be drawn several more times as you undergo the rest of the tests. This is being performed as part of this study for research purposes only.
· Whole Body, Spine and Hip Dual-Energy X-ray Absorptiometry (DEXA): This is a test to measure how much fat you have in your body and the density of your bones. For this test, you will lie still on a padded table while a scanner passes over your body. You will have three separate scans – of your whole body, hip and spine. If you are a woman and capable of getting pregnant, you will have a test to make sure you are not pregnant before each DEXA scan. This is being performed as part of this study for research purposes only.
· Meal Challenge: In this test, we feed you a customized meal tailored with a specific make-up of calories, fat, protein, and carbohydrates. We will draw a series of 10 small blood samples (about 3 teaspoons each) at specific time points before and after you eat your “challenge” meal. We will be tracking the pattern of release of the following seven hormones that may affect your appetite or the way your body handles the “challenge” meal: insulin, glucagon-like peptide-1, gastric inhibitory polypeptide, cholecystokinin, Peptide YY, glucagon and ghrelin. This is being performed as part of this study for research purposes only.
· Indirect Calorimetry (Resting Energy Expenditure): This test measures the number of calories you burn while you are resting. For this test, you will breathe into a hood (canopy) that is hooked to a machine that pumps air through the hood, while lying completely still for 30 minutes. This is being performed as part of this study for research purposes only.
· Glucose/Insulin Infusion Study: This is a test to measure your body’s sensitivity to the hormone insulin. We will infuse glucose and insulin for 2 hours and collect blood samples periodically. Glucose is a sugar that your body uses as fuel, and insulin is a hormone that helps your body process the glucose. A small amount of your blood will be used to prepare the insulin infusion; this prevents insulin from binding to the plastic syringe and tubing. Blood will be drawn every 5 minutes from a catheter in your arm, which will be placed in a warming pad, and glucose will be infused to keep your blood glucose level constant. You will have your resting energy expenditure measured again during this period. This is being performed as part of this study for research purposes only.
Where will the study take place?
All study procedures will take place at the SFGH-GCRC (standardized diet, the monitoring, and all the tests). When it is time for your surgery, you will be admitted to Moffitt-Long Hospital on the UCSF Parnassus Avenue campus as a regular hospital patient and get your surgery just like all our non-research patients.
What is a GCRC?
A nationwide network of General Clinical Research Centers (GCRC) specializes in helping doctors conduct human research with complex protocols. These centers get special funding from the National Institutes of Health and are exclusively associated with university medical centers. Any given GCRC is usually just a designated hospital ward and looks like any other. However, it functions independently with its own nursing staff, patient care facilities, procedure rooms, testing facilities, and kitchen.
Can I have family or friends visit? Can they bring things for me?
You are welcome to have visitors during regular visiting hours. They are free to socialize and bring you items of need. But they may not bring food, drink or snacks of any kind. All visitors will need to check in with the nurses as they come and go. As well, your visitors will need to fully cooperate with the nurses to make absolutely sure no food or drinks are accidentally brought to you.
Can I leave the GCRC or visit with others?
The GCRC nurses will help you arrange for opportunities to leave the GCRC and get fresh air. However, all outings must be supervised by GCRC staff. Your opportunities to leave the GCRC may be decreased if available staffing is limited.