Obesity, Diabetes Mellitus, Type 2
Conditions
Keywords
Bariatric Surgery, Gastric Bypass, Sleeve Gastrectomy, Gastroplasty
Brief summary
Recent studies have shown that bacteria within the gut play an important role in diabetes improvement after bariatric (weight-loss) surgery. Bariatric surgery fundamentally changes the environment within the gut, which results in changes to the makeup of the trillions of bacteria living within it. These changes in the gut bacteria can affect the body in a number of complex ways, which we are only just beginning to understand. For example, gut bacteria breakdown food we are unable to absorb ourselves, leading to altered sugar levels and can release molecules that act to reduce appetite. In this study we aim to find out how bariatric surgery changes the gut bacteria and how this leads to weight loss and improvement of diabetes. With this understanding we hope to discover potential targets for future treatments, such as identifying beneficial bacteria that could be supplemented with probiotics in patients. Additionally, although highly successful, up to 30% of obese patients do not undergo improvement of their diabetes after bariatric surgery. We aim to identify molecules within the patient's blood or urine that are able to predict the likely chance a patient will undergo improvement in their diabetes after bariatric surgery to help clinicians select patients most likely to benefit.
Detailed description
This study aims to assess how the gut microbiome affects the host phenotype following bariatric surgery through altered gut microbiome-host co-metabolism. The secondary objective is to identify novel biomarkers for the preoperative prognostication of T2DM remission following bariatric surgery. The study will longitudinally phenotype obese diabetics and non-diabetics undergoing Roux-en-Y Gastric Bypass or Sleeve Gastrectomy surgery. Patients will be assessed preoperatively and at 3 months and 1 year postoperatively. Clinical measures recorded will include; 1) anthropometric & physiological measurements, 2) demographic details, 3) biochemical parameters including HbA1c, 4) anti-hyperglycaemic and other medication use, 5) co-morbidity status and 6) dietary choices through 24hr dietary recall questionnaires. Blood, urine and stool samples will be collected at the above time points. Changes to the microbiome will be assessed using metagenomic sequencing. Global metabonomic profiles of serum, urine and faecal water will be generated using 1H-NMR. Further targeted analyses of bile acid and short-chain fatty acid profiles will be performed using LC-MS / GC-MS. The study will utilise multivariate statistical analysis techniques to identify metabolic pathways altered following intervention, and novel host-microbiome co-metabolism pathways that impact upon phenotype. A supervised multivariate analysis, mapping T2DM outcomes to metagenomic and metabonomic data will be performed with the aim of identifying novel preoperative biomarkers that are able to prognosticate T2DM resolution following bariatric surgery.
Interventions
Sponsors
Study design
Eligibility
Inclusion criteria
* Obese (BMI\>30kg/m2) * Type 2 Diabetes Mellitus and non-diabetic * Failure of efforts at lifestyle modification and dieting * Fitness for anaesthesia and procedure * Willingness to comply with the trial protocol
Exclusion criteria
* Previous bariatric surgery * Pregnancy or intention to become pregnant during trial period * Lack of capacity to consent * Previous major abdominal surgery (Small or large bowel resection, stomach, liver, pancreatic or splenic surgery. Does not include patients who have previously had an appendicectomy, cholecystectomy or hernia repair).
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Number of Participants With Complete Diabetes Remission at 3 Months | 3 months | Participants with HbA1c \<6% (42mmol/mol), off anti-diabetic medication, at 3 months |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Partial Diabetes Remission | 3 months | HbA1c \<6.5% (48mmol/mol), off anti-diabetic medication, at 3 months. (Includes participants with complete remission). |
| HbA1c Improvement | 3 months | Reduction in HbA1c at 3 months |
| Weight Loss | 3 months | Weight loss at 3 months |
| BMI Reduction | 3 months | BMI reduction at 3 months |
| Complete Diabetes Remission | 1 year | HbA1c \<6% (42mmol/mol), off anti-diabetic medication, at 1 year |
Countries
United Kingdom
Participant flow
Pre-assignment details
Some participants consented to give serum samples only, others were able to give complete sets of serum, 24-hour urine and stool, as detailed below.
Participants by arm
| Arm | Count |
|---|---|
| Roux-en-Y Gastric Bypass (RYGB) 50 participants gave pre-operative serum samples prior to undergoing RYGB. 23 participants underwent RYGB and gave serum samples pre and 3-months post-operatively.
13 of these gave complete sample sets of serum, 24-hour urine and stool pre and 3-months post-operation. | 50 |
| Vertical Sleeve Gastrectomy (VSG) 74 participants gave pre-operative serum samples prior to undergoing VSG. 26 participants underwent VSG and gave serum samples pre and 3-months post-operatively.
14 of these gave complete sample sets of serum, 24-hour urine and stool pre and 3-months post-operation. | 74 |
| Total | 124 |
Baseline characteristics
| Characteristic | Roux-en-Y Gastric Bypass (RYGB) | Vertical Sleeve Gastrectomy (VSG) | Total |
|---|---|---|---|
| Age, Continuous | 46.54 years STANDARD_DEVIATION 11.04 | 44.01 years STANDARD_DEVIATION 11.91 | 45.03 years STANDARD_DEVIATION 11.59 |
| BMI (kg/m2) | 44.43 Kg/m2 STANDARD_DEVIATION 5.69 | 47.12 Kg/m2 STANDARD_DEVIATION 8.99 | 46.03 Kg/m2 STANDARD_DEVIATION 7.91 |
| Diabetes Status Impaired Glucose Tolerence (IGT) | 7 Participants | 13 Participants | 20 Participants |
| Diabetes Status Non-diabetic | 16 Participants | 37 Participants | 53 Participants |
| Diabetes Status Type 2 Diabetes (T2D) | 27 Participants | 24 Participants | 51 Participants |
| Duration of T2D (years) | 7.96 years STANDARD_DEVIATION 7.03 | 7.75 years STANDARD_DEVIATION 8.47 | 7.86 years STANDARD_DEVIATION 7.66 |
| HBA1c | 52.24 mmols/mol STANDARD_DEVIATION 17.66 | 45.41 mmols/mol STANDARD_DEVIATION 12.82 | 48.16 mmols/mol STANDARD_DEVIATION 15.27 |
| Insulin use | 10 Participants | 5 Participants | 15 Participants |
| Metformin use | 26 Participants | 22 Participants | 48 Participants |
| Race and Ethnicity Not Collected | — | — | 0 Participants |
| Region of Enrollment United Kingdom | 50 participants | 74 participants | 124 participants |
| Sex: Female, Male Female | 41 Participants | 49 Participants | 90 Participants |
| Sex: Female, Male Male | 9 Participants | 25 Participants | 34 Participants |
| Weight (Kg) | 120.86 Kg STANDARD_DEVIATION 20.17 | 133.6 Kg STANDARD_DEVIATION 30.35 | 128.14 Kg STANDARD_DEVIATION 27.29 |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk | EG002 affected / at risk |
|---|---|---|---|
| deaths Total, all-cause mortality | 0 / 34 | 0 / 50 | 0 / 74 |
| other Total, other adverse events | 0 / 0 | 0 / 0 | 0 / 0 |
| serious Total, serious adverse events | 0 / 0 | 0 / 0 | 0 / 0 |
Outcome results
Number of Participants With Complete Diabetes Remission at 3 Months
Participants with HbA1c \<6% (42mmol/mol), off anti-diabetic medication, at 3 months
Time frame: 3 months
Population: Participants with complete follow up data
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Roux-en-Y Gastric Bypass | Number of Participants With Complete Diabetes Remission at 3 Months | 8 Participants |
| Vertical Sleeve Gastrectomy | Number of Participants With Complete Diabetes Remission at 3 Months | 5 Participants |
BMI Reduction
BMI reduction at 1 year
Time frame: 1 year
Population: Participants attending follow up
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Roux-en-Y Gastric Bypass | BMI Reduction | 13.8 Kg/m2 | Standard Deviation 3.69 |
| Vertical Sleeve Gastrectomy | BMI Reduction | 13.02 Kg/m2 | Standard Deviation 5.54 |
BMI Reduction
BMI reduction at 3 months
Time frame: 3 months
Population: Participants attending follow up
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Roux-en-Y Gastric Bypass | BMI Reduction | 8.87 Kg/m2 | Standard Deviation 2.99 |
| Vertical Sleeve Gastrectomy | BMI Reduction | 8.51 Kg/m2 | Standard Deviation 2.62 |
Complete Diabetes Remission
HbA1c \<6% (42mmol/mol), off anti-diabetic medication, at 1 year
Time frame: 1 year
Population: Participants with complete follow up data
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Roux-en-Y Gastric Bypass | Complete Diabetes Remission | 10 Participants |
| Vertical Sleeve Gastrectomy | Complete Diabetes Remission | 4 Participants |
HbA1c Improvement
Reduction in HbA1c at 3 months
Time frame: 3 months
Population: Participants attending follow up
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Roux-en-Y Gastric Bypass | HbA1c Improvement | 12.0 mmols/mol | Standard Deviation 11.98 |
| Vertical Sleeve Gastrectomy | HbA1c Improvement | 7.53 mmols/mol | Standard Deviation 10.18 |
HbA1c Improvement
Reduction in HbA1c at 1 year
Time frame: 1 year
Population: Participants attending follow up
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Roux-en-Y Gastric Bypass | HbA1c Improvement | 13.72 mmols/mol | Standard Deviation 13.71 |
| Vertical Sleeve Gastrectomy | HbA1c Improvement | 6.88 mmols/mol | Standard Deviation 10.19 |
Partial Diabetes Remission
HbA1c \<6.5% (48mmol/mol), off anti-diabetic medication, at 1 year. (Includes participants with complete diabetes remission).
Time frame: 1 year
Population: Participants with complete follow up data
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Roux-en-Y Gastric Bypass | Partial Diabetes Remission | 10 Participants |
| Vertical Sleeve Gastrectomy | Partial Diabetes Remission | 5 Participants |
Partial Diabetes Remission
HbA1c \<6.5% (48mmol/mol), off anti-diabetic medication, at 3 months. (Includes participants with complete remission).
Time frame: 3 months
Population: Participants with complete follow up data
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Roux-en-Y Gastric Bypass | Partial Diabetes Remission | 9 Participants |
| Vertical Sleeve Gastrectomy | Partial Diabetes Remission | 6 Participants |
Weight Loss
Weight loss at 1 year
Time frame: 1 year
Population: Participants attending follow up
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Roux-en-Y Gastric Bypass | Weight Loss | 37.53 Kg | Standard Deviation 11.36 |
| Vertical Sleeve Gastrectomy | Weight Loss | 35.23 Kg | Standard Deviation 12.98 |
Weight Loss
Weight loss at 3 months
Time frame: 3 months
Population: Participants attending follow up
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Roux-en-Y Gastric Bypass | Weight Loss | 24.13 Kg/m2 | Standard Deviation 9.13 |
| Vertical Sleeve Gastrectomy | Weight Loss | 24.00 Kg/m2 | Standard Deviation 7.94 |