None listed
Conditions
Brief summary
This study will directly compare changes in bone mass caused by intense medical treatment for obesity and by three different types of weight loss surgery (gastric banding, gastric sleeve and gastric bypass). The aim is to determine the future risk of bone loss and osteoporosis in patients who lose a large amount of weight after the weight loss surgery and through intense dieting. As surgery has been increasingly used for treatment of obesity, there is growing evidence that these procedures may result in bone abnormalities. This project will examine if hormonal changes related to surgery have an effect on the human skeleton, particularly on thickness or strength of bones. In addition, it may explain whether changes hormones (peptide YY, ghrelin and glucagon-like peptide1) are responsible for the bone mass loss, which is experienced after these procedures, independently of weight loss. This study will also investigate if the weight loss and rapid improvement in diabetes control observed after gastric bypass surgery are driven by the changes in hormones such as leptin and peptide YY. Importantly, our study will pave the way for development of diagnostic test, which will predict if the prospective patient will benefit (or not) from the different forms of weight loss surgery.
Interventions
The aim of this project is to define the role of neuropeptides and gut hormones in the regulation of adipose and bone metabolism in patients undergoing massive weight loss.
Each patient will attend 6 study visits: at baseline 0, 1, 3, 6, 12, 24 and 36 months with the extended follow up for the surgical groups up to 3 years post interventions.
The following tests will be carried out during the study:
Height, weight and waist measurements: these will be measured at each study visit.
Blood Co
The aim of this project is to define the role of neuropeptides and gut hormones in the regulation of adipose and bone metabolism in patients undergoing massive weight loss. Each patient will attend 6 study visits: at baseline 0, 1, 3, 6, 12, 24 and 36 months with the extended follow up for the surgical groups up to 3 years post interventions. The following tests will be carried out during the study: Height, weight and waist measurements: these will be measured at each study visit. Blood Collection at each visit: for biochemistry including urea, creatinine, electrolytes (UEC), full blood count (FBC), liver function tests (LFT), HbA1c in patients with DM, total cholesterol, HDL, LDL and triglycerides, fasting BSL and insulin, mineral and vitamin levels relevant to this study as well as gut hormones: peptide YY, measuring both full length (PYY 1-36) and the fragment (PYY 3-36), ghrelin, glucagon like peptide (GLP-1), leptin as well as adiponectin.For the surgical subjects, screening prior to the study will be done to exclude abnormal hormonal status such as hypercortisolaemia, hypogonadism and thyroid dysfunction. Meal studies at visits: 0, 6 months (optional), 12 and 36 months to assess postprandial response of gut hormones Bone and calcium markers: at baseline, 3, 6, 12 months and 24 months calcium balance will be assessed by 24-hour urine calcium collections. Calcium, phosphate, albumin, intact parathyroid hormone and 25-hydroxyvitamin D as well as markers of bone formation (serum osteocalcin) and bone resorption (urinary N telopeptide (NTx) will be measured at these time points. Bone mineral densitometry scan (BMD DXA): at visits: 0, 12 months, 24 months and 36 months to assess BMD and body composition Quantitative Computed Tomography (QCT): at visits: 0, 12 months and 2 years to assess BMD and abdominal fat mass 3 day food diary analysis with nutrient assessments at each visit. Questionnaires including: The Satiety Assessment Questionnaire The Physical Activity Questionnaire (3-day recall, once a month) Calcium and vitamin D supplements will be recommended to all subjects to aim for total calcium intake from diet and supplements> 1000mg a day and 25(OH) vitamin D level>75nM.
Sponsors
A/Prof Jacqueline Ruth Center
Eligibility
Sex/Gender
All
Age
18 Years to 70 Years
Healthy volunteers
No
Inclusion criteria
1) BMI> 40 or BMI> 35 with medical complication from obesity 2) Presence of obesity for the last 5 years, which has persisted despite multiple attempts with other weight loss measures 3) Patient who is either undergoing bariatric surgery or who is enrolled into the intense medical management plan with the aim to lose significant amount of weight. 4) Willingness and ability to comply with the protocol of the study 5) Willingness to provide written informed consent
Exclusion criteria
1) Pregnancy or patient planning pregnancy in next 2 years of the study 2) Women, who are within 5 years after the onset of menopause 3) Intake of medications known to affect bone mineral density (BMD) 4) Active alcohol or drug dependency 5) Active psychosocial or psychiatric problem that would make adherence to the protocol difficult
Outcome results
None listed