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Longitudinal Phenotyping of Bariatric Surgery Patients

Longitudinal Phenotyping of Bariatric Surgery Patients

Status
Completed
Phases
Unknown
Study type
Observational
Source
ClinicalTrials.gov
Registry ID
NCT02421055
Enrollment
158
Registered
2015-04-20
Start date
2015-06-30
Completion date
2019-02-28
Last updated
2020-11-06

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Obesity, Diabetes Mellitus, Type 2

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

PROCEDURELaparoscopic Sleeve Gastrectomy

Sponsors

Imperial College London
Lead SponsorOTHER

Study design

Observational model
COHORT
Time perspective
PROSPECTIVE

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

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

MeasureTime frameDescription
Number of Participants With Complete Diabetes Remission at 3 Months3 monthsParticipants with HbA1c \<6% (42mmol/mol), off anti-diabetic medication, at 3 months

Secondary

MeasureTime frameDescription
Partial Diabetes Remission3 monthsHbA1c \<6.5% (48mmol/mol), off anti-diabetic medication, at 3 months. (Includes participants with complete remission).
HbA1c Improvement3 monthsReduction in HbA1c at 3 months
Weight Loss3 monthsWeight loss at 3 months
BMI Reduction3 monthsBMI reduction at 3 months
Complete Diabetes Remission1 yearHbA1c \<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

ArmCount
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
Total124

Baseline characteristics

CharacteristicRoux-en-Y Gastric Bypass (RYGB)Vertical Sleeve Gastrectomy (VSG)Total
Age, Continuous46.54 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 Participants13 Participants20 Participants
Diabetes Status
Non-diabetic
16 Participants37 Participants53 Participants
Diabetes Status
Type 2 Diabetes (T2D)
27 Participants24 Participants51 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
HBA1c52.24 mmols/mol
STANDARD_DEVIATION 17.66
45.41 mmols/mol
STANDARD_DEVIATION 12.82
48.16 mmols/mol
STANDARD_DEVIATION 15.27
Insulin use10 Participants5 Participants15 Participants
Metformin use26 Participants22 Participants48 Participants
Race and Ethnicity Not Collected0 Participants
Region of Enrollment
United Kingdom
50 participants74 participants124 participants
Sex: Female, Male
Female
41 Participants49 Participants90 Participants
Sex: Female, Male
Male
9 Participants25 Participants34 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 typeEG000
affected / at risk
EG001
affected / at risk
EG002
affected / at risk
deaths
Total, all-cause mortality
0 / 340 / 500 / 74
other
Total, other adverse events
0 / 00 / 00 / 0
serious
Total, serious adverse events
0 / 00 / 00 / 0

Outcome results

Primary

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

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Roux-en-Y Gastric BypassNumber of Participants With Complete Diabetes Remission at 3 Months8 Participants
Vertical Sleeve GastrectomyNumber of Participants With Complete Diabetes Remission at 3 Months5 Participants
Secondary

BMI Reduction

BMI reduction at 1 year

Time frame: 1 year

Population: Participants attending follow up

ArmMeasureValue (MEAN)Dispersion
Roux-en-Y Gastric BypassBMI Reduction13.8 Kg/m2Standard Deviation 3.69
Vertical Sleeve GastrectomyBMI Reduction13.02 Kg/m2Standard Deviation 5.54
Secondary

BMI Reduction

BMI reduction at 3 months

Time frame: 3 months

Population: Participants attending follow up

ArmMeasureValue (MEAN)Dispersion
Roux-en-Y Gastric BypassBMI Reduction8.87 Kg/m2Standard Deviation 2.99
Vertical Sleeve GastrectomyBMI Reduction8.51 Kg/m2Standard Deviation 2.62
Secondary

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

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Roux-en-Y Gastric BypassComplete Diabetes Remission10 Participants
Vertical Sleeve GastrectomyComplete Diabetes Remission4 Participants
Secondary

HbA1c Improvement

Reduction in HbA1c at 3 months

Time frame: 3 months

Population: Participants attending follow up

ArmMeasureValue (MEAN)Dispersion
Roux-en-Y Gastric BypassHbA1c Improvement12.0 mmols/molStandard Deviation 11.98
Vertical Sleeve GastrectomyHbA1c Improvement7.53 mmols/molStandard Deviation 10.18
Secondary

HbA1c Improvement

Reduction in HbA1c at 1 year

Time frame: 1 year

Population: Participants attending follow up

ArmMeasureValue (MEAN)Dispersion
Roux-en-Y Gastric BypassHbA1c Improvement13.72 mmols/molStandard Deviation 13.71
Vertical Sleeve GastrectomyHbA1c Improvement6.88 mmols/molStandard Deviation 10.19
Secondary

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

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Roux-en-Y Gastric BypassPartial Diabetes Remission10 Participants
Vertical Sleeve GastrectomyPartial Diabetes Remission5 Participants
Secondary

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

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Roux-en-Y Gastric BypassPartial Diabetes Remission9 Participants
Vertical Sleeve GastrectomyPartial Diabetes Remission6 Participants
Secondary

Weight Loss

Weight loss at 1 year

Time frame: 1 year

Population: Participants attending follow up

ArmMeasureValue (MEAN)Dispersion
Roux-en-Y Gastric BypassWeight Loss37.53 KgStandard Deviation 11.36
Vertical Sleeve GastrectomyWeight Loss35.23 KgStandard Deviation 12.98
Secondary

Weight Loss

Weight loss at 3 months

Time frame: 3 months

Population: Participants attending follow up

ArmMeasureValue (MEAN)Dispersion
Roux-en-Y Gastric BypassWeight Loss24.13 Kg/m2Standard Deviation 9.13
Vertical Sleeve GastrectomyWeight Loss24.00 Kg/m2Standard Deviation 7.94

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026