Obesity, MorbidCOBRA stadyNCT06794892
Comparative Outcomes of One-Anastomosis Gastric Bypass and Roux-en-Y Gastric Bypass As Revisional Procedures Following Failed Restrictive Bariatric Surgery
An observational study of Obesity, Morbid and Type 2 Diabetes Mellitus (T2DM), run by Azienda Sanitaria Locale Napoli 2 Nord at 1 site in Italy.
Trial summary
Study Description This prospective, multicenter study aims to compare the outcomes of One-Anastomosis Gastric Bypass (OAGB) and Roux-en-Y Gastric Bypass (RYGB) as revisional procedures for patients experiencing insufficient weight loss or weight regain following restrictive bariatric surgeries, such as laparoscopic… Read more about this study
- Who is it for?
- Ages 18 to 65 years
- Conditions the study is for
- Obesity, Morbid, Type 2 Diabetes Mellitus (T2DM), Hypertension
- How many people
- 328 participants
- Where
- 1 siteItaly
- Study dates
- 1 Jan 2019to 30 Jan 2024
- Phase
- Observational
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 65 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Study population: Study participants will be selected from a population of adults aged 18 to 65 years who have undergone primary restrictive bariatric surgery, such as laparoscopic sleeve gastrectomy (LSG) or laparoscopic adjustable gastric banding (LAGB), and have experienced insufficient weight loss or significant weight regain. This population will include individuals from multiple high-volume bariatric centers, ensuring a diverse cohort representing a range of demographic, clinical, and surgical characteristics. Eligible participants must meet specific criteria, such as a body mass index (BMI) ≤ 40 kg/m² and stable comorbid conditions. The study will focus on patients who require revisional bariatric surgery and are deemed suitable candidates for One-Anastomosis Gastric Bypass (OAGB) or Roux-en-Y Gastric Bypass (RYGB). Patients with specific contraindications, such as ongoing acute medical conditions or inability to provide informed consent, will be excluded to maintain the integrity and safety of
Who may be able to join
- Adults aged 18-65 years.
- Experienced insufficient weight loss, defined as:
- Excess weight loss (EWL) < 50%.
- Total weight loss (TWL) < 25%.
- BMI > 40 kg/m² at least two years after primary restrictive surgery.
- Previously underwent laparoscopic sleeve gastrectomy (LSG) or laparoscopic adjustable gastric banding (LAGB).
- Undergoing revisional surgery specifically for inadequate weight loss or weight regain.
Who cannot join
- Revisional surgery performed for indications other than inadequate weight loss or weight regain (e.g., complications of the primary procedure such as stenosis or refractory gastroesophageal reflux, or for comorbidity management).
- Known psychiatric illness or untreated eating disorders.
- Pregnancy.
- History of prior gastric surgery unrelated to bariatric interventions.
Trial locations and contacts
1 site in 1 country.
About this study
Official title: Comparative Outcomes of One-Anastomosis Gastric Bypass and Roux-en-Y Gastric Bypass As Revisional Procedures Following Failed Restrictive Bariatric Surgery: a Prospective Multicenter Study with Three-Year Follow-Up
Study Description
This prospective, multicenter study aims to compare the outcomes of One-Anastomosis Gastric Bypass (OAGB) and Roux-en-Y Gastric Bypass (RYGB) as revisional procedures for patients experiencing insufficient weight loss or weight regain following restrictive bariatric surgeries, such as laparoscopic sleeve gastrectomy (LSG) or laparoscopic adjustable gastric banding (LAGB). Conducted between January 2019 and December 2021, the study involves a three-year follow-up of 328 patients across high-volume bariatric centers.
Read more
The primary objective is to evaluate the effectiveness of these revisional procedures in achieving additional weight loss. Secondary objectives include analyzing differences in operative times, complication rates (short- and long-term), reduction of obesity-related comorbidities, mortality, and overall patient outcomes.
This study uniquely integrates comprehensive pre- and postoperative assessments, including radiological evaluations, to better understand predictors of success and provide evidence for optimal surgical strategies in revisional bariatric care.
Read the detailed description
Study Objective and Design
The primary objective of this multicenter study was to compare the effectiveness of one-anastomosis gastric bypass and Roux-en-Y gastric bypass as revisional procedures for addressing insufficient weight loss or weight regain following failed primary restrictive bariatric surgery. Effectiveness was measured in terms of additional weight loss. Secondary objectives included comparisons of surgical duration, reduction in obesity-related comorbidities, rates of short- and long-term complications, and mortality between the two revisional approaches. The study was conducted from January 2019 to December 2021, with a three-year follow-up for each participant.
Patient Selection and Data Collection
Participants were recruited from four high-volume bariatric centers in Italy. Inclusion criteria encompassed adults aged 18 to 65 years who exhibited insufficient weight loss, defined as excess weight loss of less than 50%, total weight loss of less than 25%, or a BMI greater than 40 kg/m² at least two years after undergoing laparoscopic sleeve gastrectomy or laparoscopic adjustable gastric banding. Eligible patients were those requiring revisional surgery exclusively for inadequate weight loss or regain. Exclusion criteria included revisional surgery for other indications (e.g., complications such as stenosis or severe gastroesophageal reflux), untreated psychiatric illness, active eating disorders, pregnancy, or any previous gastric surgery unrelated to bariatric interventions.
Preoperative assessments involved a multidisciplinary team including an endocrinologist, dietitian, and psychologist. Patients identified with maladaptive eating patterns received treatment before surgery to optimize outcomes. Baseline data on demographics, preoperative BMI, and comorbidities were collected and followed up throughout the study. Ethical approval was obtained from all participating centers' medical ethics committees.
Surgical Technique and Perioperative Management
One-Anastomosis Gastric Bypass
The surgical protocol for one-anastomosis gastric bypass involved removing the gastric band in patients previously treated with laparoscopic adjustable gastric banding, followed by dissection of the angle of His. If present, the fibrous capsule from the band was excised. A gastric pouch was created by horizontally transecting the stomach at the junction of the corpus and antrum, typically at the level of the crow's foot. For patients with a prior sleeve gastrectomy, the residual sleeve was horizontally transected. The length of the biliopancreatic limb was tailored based on the patient's preoperative BMI, ranging from 180 to 200 cm.
Roux-en-Y Gastric Bypass
For Roux-en-Y gastric bypass, the gastric band and fibrous capsule were removed in previously banded patients, followed by adhesiolysis as necessary. A small gastric pouch was created by transecting the stomach. The lengths of the alimentary and biliopancreatic limbs were standardized across centers. Closure of mesenteric defects was performed at the surgeon's discretion.
Data Collection
Type 2 Diabetes Mellitus
Type 2 diabetes mellitus was diagnosed according to established guidelines, based on fasting plasma glucose readings above 126 mg/dL, a two-hour glucose level exceeding 200 mg/dL during an oral glucose tolerance test, or a glycated hemoglobin level above 6.5%. Complete remission was defined as fasting plasma glucose levels below 100 mg/dL and HbA1c less than 6.0% without antidiabetic medications. Follow-ups were conducted at 3, 6, 12, 24, and 36 months post-revision.
Hypertension
Hypertension was defined as systolic blood pressure greater than or equal to 140 mmHg or diastolic pressure greater than or equal to 90 mmHg. Remission was defined as achieving blood pressure below 120/80 mmHg without antihypertensive medications. Blood pressure measurements were taken at 3, 6, 12, 24, and 36 months.
Obstructive Sleep Apnea Syndrome
Obstructive sleep apnea was diagnosed based on prior polysomnography, with an Apnea-Hypopnea Index exceeding 15 events/hour or more than 5 events/hour in the presence of related symptoms such as snoring or daytime sleepiness. Remission was defined by resolution of these symptoms. Follow-up assessments occurred at 3, 6, 12, 24, and 36 months.
Outcome Measures
Baseline characteristics, including demographics, preoperative BMI, and comorbidities, were recorded at study entry.
Primary Outcomes
- Percentage Total Weight Loss: Measured as the proportion of total body weight lost relative to initial weight.
- Percentage Excess BMI Loss: Calculated as the proportion of BMI lost relative to the amount exceeding a BMI of 25.
Secondary Outcomes
- Mortality: Measured throughout the three-year follow-up.
- Complications: Assessed using the Clavien-Dindo classification. Short-term complications included anastomotic leaks, bleeding, infections, perforations, myocardial infarction, and stroke. Long-term complications included nutritional deficiencies, gastric ulcers, strictures, bile reflux, internal herniation, and malnutrition.
- Comorbidity Improvement: Evaluated using standardized criteria for resolution or improvement of type 2 diabetes, cardiovascular disease, obstructive sleep apnea, dyslipidemia, and osteoarthritis.
Quality of Life Outcomes
Quality of life was assessed using validated tools such as the SF-36 at multiple intervals: baseline, and 3, 6, 12, 24, and 36 months post-surgery. Domains evaluated included physical health, mobility, social functioning, emotional well-being, and fatigue. Quality-of-life trends were compared between the two surgical groups to identify differences in patient-reported outcomes.
This structured approach provides a comprehensive evaluation of surgical and patient-centered outcomes in revisional bariatric surgery.Study Objective and Design
The primary objective of this multicenter study was to compare the effectiveness of one-anastomosis gastric bypass and Roux-en-Y gastric bypass as revisional procedures for addressing insufficient weight loss or weight regain following failed primary restrictive bariatric surgery. Effectiveness was measured in terms of additional weight loss. Secondary objectives included comparisons of surgical duration, reduction in obesity-related comorbidities, rates of short- and long-term complications, and mortality between the two revisional approaches. The study was conducted from January 2019 to December 2021, with a three-year follow-up for each participant.
Patient Selection and Data Collection
Participants were recruited from four high-volume bariatric centers in Italy. Inclusion criteria encompassed adults aged 18 to 65 years who exhibited insufficient weight loss, defined as excess weight loss of less than 50%, total weight loss of less than 25%, or a BMI greater than 40 kg/m² at least two years after undergoing laparoscopic sleeve gastrectomy or laparoscopic adjustable gastric banding. Eligible patients were those requiring revisional surgery exclusively for inadequate weight loss or regain. Exclusion criteria included revisional surgery for other indications (e.g., complications such as stenosis or severe gastroesophageal reflux), untreated psychiatric illness, active eating disorders, pregnancy, or any previous gastric surgery unrelated to bariatric interventions.
Preoperative assessments involved a multidisciplinary team including an endocrinologist, dietitian, and psychologist. Patients identified with maladaptive eating patterns received treatment before surgery to optimize outcomes. Baseline data on demographics, preoperative BMI, and comorbidities were collected and followed up throughout the study. Ethical approval was obtained from all participating centers' medical ethics committees.
Surgical Technique and Perioperative Management
One-Anastomosis Gastric Bypass
The surgical protocol for one-anastomosis gastric bypass involved removing the gastric band in patients previously treated with laparoscopic adjustable gastric banding, followed by dissection of the angle of His. If present, the fibrous capsule from the band was excised. A gastric pouch was created by horizontally transecting the stomach at the junction of the corpus and antrum, typically at the level of the crow's foot. For patients with a prior sleeve gastrectomy, the residual sleeve was horizontally transected. The length of the biliopancreatic limb was tailored based on the patient's preoperative BMI, ranging from 180 to 200 cm.
Roux-en-Y Gastric Bypass
For Roux-en-Y gastric bypass, the gastric band and fibrous capsule were removed in previously banded patients, followed by adhesiolysis as necessary. A small gastric pouch was created by transecting the stomach. The lengths of the alimentary and biliopancreatic limbs were standardized across centers. Closure of mesenteric defects was performed at the surgeon's discretion.
Data Collection
Type 2 Diabetes Mellitus
Type 2 diabetes mellitus was diagnosed according to established guidelines, based on fasting plasma glucose readings above 126 mg/dL, a two-hour glucose level exceeding 200 mg/dL during an oral glucose tolerance test, or a glycated hemoglobin level above 6.5%. Complete remission was defined as fasting plasma glucose levels below 100 mg/dL and HbA1c less than 6.0% without antidiabetic medications. Follow-ups were conducted at 3, 6, 12, 24, and 36 months post-revision.
Hypertension
Hypertension was defined as systolic blood pressure greater than or equal to 140 mmHg or diastolic pressure greater than or equal to 90 mmHg. Remission was defined as achieving blood pressure below 120/80 mmHg without antihypertensive medications. Blood pressure measurements were taken at 3, 6, 12, 24, and 36 months.
Obstructive Sleep Apnea Syndrome
Obstructive sleep apnea was diagnosed based on prior polysomnography, with an Apnea-Hypopnea Index exceeding 15 events/hour or more than 5 events/hour in the presence of related symptoms such as snoring or daytime sleepiness. Remission was defined by resolution of these symptoms. Follow-up assessments occurred at 3, 6, 12, 24, and 36 months.
Outcome Measures
Baseline characteristics, including demographics, preoperative BMI, and comorbidities, were recorded at study entry.
Primary Outcomes
- Percentage Total Weight Loss: Measured as the proportion of total body weight lost relative to initial weight.
- Percentage Excess BMI Loss: Calculated as the proportion of BMI lost relative to the amount exceeding a BMI of 25.
Secondary Outcomes
- Mortality: Measured throughout the three-year follow-up.
- Complications: Assessed using the Clavien-Dindo classification. Short-term complications included anastomotic leaks, bleeding, infections, perforations, myocardial infarction, and stroke. Long-term complications included nutritional deficiencies, gastric ulcers, strictures, bile reflux, internal herniation, and malnutrition.
- Comorbidity Improvement: Evaluated using standardized criteria for resolution or improvement of type 2 diabetes, cardiovascular disease, obstructive sleep apnea, dyslipidemia, and osteoarthritis.
Quality of Life Outcomes
Quality of life was assessed using validated tools such as the SF-36 at multiple intervals: baseline, and 3, 6, 12, 24, and 36 months post-surgery. Domains evaluated included physical health, mobility, social functioning, emotional well-being, and fatigue. Quality-of-life trends were compared between the two surgical groups to identify differences in patient-reported outcomes.
- Keywords
- obesity, One anastomosis gastric bypass, Roux and Y gastric Bypass
- Medical subject headings
- Obesity, Morbid, Diabetes Mellitus, Type 2, Hypertension, Dyslipidemias, Obesity
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
| Study group | Role | What they receive |
|---|---|---|
| OAGB Cohort - Patients undergoing One-Anastomosis Gastric Bypass as a revisional procedure. | OAGB Cohort: This group consists of patients who underwent One-Anastomosis Gastric Bypass (OAGB) as a revisional bariatric procedure following insufficient weight loss or weight regain after primary restrictive surgeries, such as laparoscopic sleeve gastrectomy (LSG) or laparoscopic adjustable gastric banding (LAGB). These patients were monitored over three years to evaluate outcomes, including weight loss, complication rates, and improvement in obesity-related comorbidities. | |
| RYGB Cohort - Patients undergoing Roux-en-Y Gastric Bypass as a revisional procedure. | RYGB Cohort: This group includes patients who underwent Roux-en-Y Gastric Bypass (RYGB) as a revisional bariatric procedure due to insufficient weight loss or significant weight regain after primary restrictive surgeries, such as laparoscopic sleeve gastrectomy (LSG) or laparoscopic adjustable gastric banding (LAGB). The cohort was followed prospectively over three years to assess outcomes, including weight loss, resolution of obesity-related comorbidities, complication rates, and overall surgical success. |
What is being measured
The primary outcome is the main question the study is designed to answer.
Percentage Total Weight Loss (%TWL)
The percentage of total body weight lost from the pre-revisional weight to the weight at 36 months post-revision.
Measured: Measured at 12 months post-surgery.
Percentage Total Weight Loss (%TWL)
The percentage of total body weight lost from the pre-revisional weight to the weight at 36 months post-revision.
Measured: Measured at 24, months post-surgery.
Percentage Total Weight Loss (%TWL)
The percentage of total body weight lost from the pre-revisional weight to the weight at 36 months post-revision.
Measured: Measured at 36 months post-surgery.
Secondary outcomes (21)
Percentage Excess BMI Loss (%EBMIL)
The percentage reduction in excess BMI relative to an ideal BMI of 25, calculated at 12 months post-revision.
Measured: Measured at 12 months post-surgery
Percentage Excess BMI Loss (%EBMIL)
The percentage change in excess BMI relative to an ideal BMI of 25, calculated at 24 months following revisional surgery. This measure evaluates the change in excess BMI to assess the effectiveness of the revisional bariatric procedure.
Measured: Measured at 24 months post-surgery
Percentage Excess BMI Loss (%EBMIL)
The percentage change in excess BMI relative to an ideal BMI of 25, calculated at 24 months following revisional surgery. This measure evaluates the change in excess BMI to assess the effectiveness of the revisional bariatric procedure.
Measured: Measured at 36 months post-surgery
Reduction in Obesity-Related Comorbidities
Description: Improvement or resolution of comorbid conditions, including type 2 diabetes mellitus (T2DM), hypertension, dyslipidemia, and obstructive sleep apnea syndrome (OSAS).
Measured: 36 months
Complication Rates
Incidence of short-term (≤30 days) and long-term (>30 days) surgical complications, including anastomotic leaks, internal herniation, biliary reflux, and malnutrition.
Measured: until 30 days follow-up period.
Complication Rates
Incidence of short-term (≤30 days) and long-term (>30 days) surgical complications, including anastomotic leaks, internal herniation, biliary reflux, and malnutrition.
Measured: 36-month follow-up period.
Mortality Rate
The percentage of patients who die from any cause during the 36-month follow-up period.
Measured: 36 months post-surgery.
Quality of Life (QoL) Assessment
Description: Patient-reported outcomes measured using a validated tool such as the SF-36 or Bariatric Quality of Life Index
Measured: Baseline
Quality of Life (QoL) Assessment
Description: Patient-reported outcomes measured using a validated tool such as the SF-36 or Bariatric Quality of Life Index
Measured: , 12 months post-surgery
Quality of Life (QoL) Assessment
Description: Patient-reported outcomes measured using a validated tool such as the SF-36 or Bariatric Quality of Life Index
Measured: 24, months post-surgery months post-surgery
Quality of Life (QoL) Assessment
Description: Patient-reported outcomes measured using a validated tool such as the SF-36 or Bariatric Quality of Life Index
Measured: 36 months post-surgery, months post-surgery months post-surgery
Remission of Hypertension (HTN)
Achieving normal blood pressure levels (< 120/80 mmHg) without the use of antihypertensive medications. Hypertension was defined as systolic blood pressure ≥ 140 mmHg or diastolic blood pressure ≥ 90 mmHg.
Measured: Measured at 3, months post-revision.
Remission of Hypertension (HTN)
Achieving normal blood pressure levels (< 120/80 mmHg) without the use of antihypertensive medications. Hypertension was defined as systolic blood pressure ≥ 140 mmHg or diastolic blood pressure ≥ 90 mmHg.
Measured: Measured at 6, months post-revision.
Remission of Hypertension (HTN)
Achieving normal blood pressure levels (< 120/80 mmHg) without the use of antihypertensive medications. Hypertension was defined as systolic blood pressure ≥ 140 mmHg or diastolic blood pressure ≥ 90 mmHg.
Measured: Measured at 12, months post-revision.
Remission of Hypertension (HTN)
Achieving normal blood pressure levels (< 120/80 mmHg) without the use of antihypertensive medications. Hypertension was defined as systolic blood pressure ≥ 140 mmHg or diastolic blood pressure ≥ 90 mmHg.
Measured: Measured at 24, months post-revision.
Remission of Hypertension (HTN)
Achieving normal blood pressure levels (< 120/80 mmHg) without the use of antihypertensive medications. Hypertension was defined as systolic blood pressure ≥ 140 mmHg or diastolic blood pressure ≥ 90 mmHg.
Measured: Measured at 36, months post-revision.
Type 2 Diabetes Mellitus (T2DM)
Partial remission of Type 2 Diabetes Mellitus T2DM, defined as improved glycemic control with reduced medication doses but without meeting the criteria for complete remission.
Measured: Assessed at 3,months post-revision
Type 2 Diabetes Mellitus (T2DM)
Partial remission of Type 2 Diabetes Mellitus T2DM, defined as improved glycemic control with reduced medication doses but without meeting the criteria for complete remission.
Measured: Assessed at 6months post-revision
Type 2 Diabetes Mellitus (T2DM)
Partial remission of Type 2 Diabetes Mellitus T2DM, defined as improved glycemic control with reduced medication doses but without meeting the criteria for complete remission.
Measured: Assessed at 12 months post-revision
Type 2 Diabetes Mellitus (T2DM)
Partial remission of Type 2 Diabetes Mellitus T2DM, defined as improved glycemic control with reduced medication doses but without meeting the criteria for complete remission.
Measured: Assessed at 24 months post-revision
Type 2 Diabetes Mellitus (T2DM)
Partial remission of Type 2 Diabetes Mellitus T2DM, defined as improved glycemic control with reduced medication doses but without meeting the criteria for complete remission.
Measured: Assessed at 36 months post-revision
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted27 Jan 2025
- Study start1 Jan 2019
- Primary completion31 Dec 2021
- Study completion30 Jan 2024
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Obesity, MorbidStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Cohort
- Time perspective
- Retrospective
- Enrolment
- 328 participants (actual)
Sponsor and investigators
- Lead sponsor
- Azienda Sanitaria Locale Napoli 2 Nord
- Sponsor type
- University, hospital or other
- Collaborators
- University of Campania Luigi Vanvitelli
- Responsible party
- Principal investigator, Francesco Pizza, Azienda Sanitaria Locale Napoli 2 Nord
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06794892
- Sponsor's protocol ID
- 2025010188
- Acronym
- COBRA stady
- Status last verified
- Jan 2025
- First submitted
- 21 Jan 2025
- Last updated
- 28 Jan 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 28 Jan 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Comparative Outcomes of One-Anastomosis Gastric Bypass and Roux-en-Y Gastric Bypass As Revisional Procedures Following Failed Restrictive Bariatric Surgery: a Prospective Multicenter Study with Three-Year Follow-Up
- ClinicalTrials.gov ID
- NCT06794892
- Acronym / sponsor ID
- COBRA stady / 2025010188
- Keywords
- obesity, One anastomosis gastric bypass, Roux and Y gastric Bypass
- Study type
- Observational
- Recruitment status
- Completed
- Enrolment
- 328 participants (actual)
- Lead sponsor
- Azienda Sanitaria Locale Napoli 2 NordUniversity, hospital or other
- Collaborators
- University of Campania Luigi Vanvitelli
- Study start
- 1 Jan 2019 (actual)
- Primary completion
- 31 Dec 2021 (actual)
- Study completion
- 30 Jan 2024 (actual)
- First posted
- 27 Jan 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Study Description
This prospective, multicenter study aims to compare the outcomes of One-Anastomosis Gastric Bypass (OAGB) and Roux-en-Y Gastric Bypass (RYGB) as revisional procedures for patients experiencing insufficient weight loss or weight regain following restrictive bariatric surgeries, such as laparoscopic sleeve gastrectomy (LSG) or laparoscopic adjustable gastric banding (LAGB). Conducted between January 2019 and December 2021, the study involves a three-year follow-up of 328 patients across high-volume bariatric centers.
The primary objective is to evaluate the effectiveness of these revisional procedures in achieving additional weight loss. Secondary objectives include analyzing differences in operative times, complication rates (short- and long-term), reduction of obesity-related comorbidities, mortality, and overall patient outcomes.
This study uniquely integrates comprehensive pre- and postoperative assessments, including radiological evaluations, to better understand predictors of success and provide evidence for optimal surgical strategies in revisional bariatric care.
Detailed description
Study Objective and Design
The primary objective of this multicenter study was to compare the effectiveness of one-anastomosis gastric bypass and Roux-en-Y gastric bypass as revisional procedures for addressing insufficient weight loss or weight regain following failed primary restrictive bariatric surgery. Effectiveness was measured in terms of additional weight loss. Secondary objectives included comparisons of surgical duration, reduction in obesity-related comorbidities, rates of short- and long-term complications, and mortality between the two revisional approaches. The study was conducted from January 2019 to December 2021, with a three-year follow-up for each participant.
Patient Selection and Data Collection
Participants were recruited from four high-volume bariatric centers in Italy. Inclusion criteria encompassed adults aged 18 to 65 years who exhibited insufficient weight loss, defined as excess weight loss of less than 50%, total weight loss of less than 25%, or a BMI greater than 40 kg/m² at least two years after undergoing laparoscopic sleeve gastrectomy or laparoscopic adjustable gastric banding. Eligible patients were those requiring revisional surgery exclusively for inadequate weight loss or regain. Exclusion criteria included revisional surgery for other indications (e.g., complications such as stenosis or severe gastroesophageal reflux), untreated psychiatric illness, active eating disorders, pregnancy, or any previous gastric surgery unrelated to bariatric interventions.
Preoperative assessments involved a multidisciplinary team including an endocrinologist, dietitian, and psychologist. Patients identified with maladaptive eating patterns received treatment before surgery to optimize outcomes. Baseline data on demographics, preoperative BMI, and comorbidities were collected and followed up throughout the study. Ethical approval was obtained from all participating centers' medical ethics committees.
Surgical Technique and Perioperative Management
One-Anastomosis Gastric Bypass
The surgical protocol for one-anastomosis gastric bypass involved removing the gastric band in patients previously treated with laparoscopic adjustable gastric banding, followed by dissection of the angle of His. If present, the fibrous capsule from the band was excised. A gastric pouch was created by horizontally transecting the stomach at the junction of the corpus and antrum, typically at the level of the crow's foot. For patients with a prior sleeve gastrectomy, the residual sleeve was horizontally transected. The length of the biliopancreatic limb was tailored based on the patient's preoperative BMI, ranging from 180 to 200 cm.
Roux-en-Y Gastric Bypass
For Roux-en-Y gastric bypass, the gastric band and fibrous capsule were removed in previously banded patients, followed by adhesiolysis as necessary. A small gastric pouch was created by transecting the stomach. The lengths of the alimentary and biliopancreatic limbs were standardized across centers. Closure of mesenteric defects was performed at the surgeon's discretion.
Data Collection
Type 2 Diabetes Mellitus
Type 2 diabetes mellitus was diagnosed according to established guidelines, based on fasting plasma glucose readings above 126 mg/dL, a two-hour glucose level exceeding 200 mg/dL during an oral glucose tolerance test, or a glycated hemoglobin level above 6.5%. Complete remission was defined as fasting plasma glucose levels below 100 mg/dL and HbA1c less than 6.0% without antidiabetic medications. Follow-ups were conducted at 3, 6, 12, 24, and 36 months post-revision.
Hypertension
Hypertension was defined as systolic blood pressure greater than or equal to 140 mmHg or diastolic pressure greater than or equal to 90 mmHg. Remission was defined as achieving blood pressure below 120/80 mmHg without antihypertensive medications. Blood pressure measurements were taken at 3, 6, 12, 24, and 36 months.
Obstructive Sleep Apnea Syndrome
Obstructive sleep apnea was diagnosed based on prior polysomnography, with an Apnea-Hypopnea Index exceeding 15 events/hour or more than 5 events/hour in the presence of related symptoms such as snoring or daytime sleepiness. Remission was defined by resolution of these symptoms. Follow-up assessments occurred at 3, 6, 12, 24, and 36 months.
Outcome Measures
Baseline characteristics, including demographics, preoperative BMI, and comorbidities, were recorded at study entry.
Primary Outcomes
- Percentage Total Weight Loss: Measured as the proportion of total body weight lost relative to initial weight.
- Percentage Excess BMI Loss: Calculated as the proportion of BMI lost relative to the amount exceeding a BMI of 25.
Secondary Outcomes
- Mortality: Measured throughout the three-year follow-up.
- Complications: Assessed using the Clavien-Dindo classification. Short-term complications included anastomotic leaks, bleeding, infections, perforations, myocardial infarction, and stroke. Long-term complications included nutritional deficiencies, gastric ulcers, strictures, bile reflux, internal herniation, and malnutrition.
- Comorbidity Improvement: Evaluated using standardized criteria for resolution or improvement of type 2 diabetes, cardiovascular disease, obstructive sleep apnea, dyslipidemia, and osteoarthritis.
Quality of Life Outcomes
Quality of life was assessed using validated tools such as the SF-36 at multiple intervals: baseline, and 3, 6, 12, 24, and 36 months post-surgery. Domains evaluated included physical health, mobility, social functioning, emotional well-being, and fatigue. Quality-of-life trends were compared between the two surgical groups to identify differences in patient-reported outcomes.
This structured approach provides a comprehensive evaluation of surgical and patient-centered outcomes in revisional bariatric surgery.Study Objective and Design
The primary objective of this multicenter study was to compare the effectiveness of one-anastomosis gastric bypass and Roux-en-Y gastric bypass as revisional procedures for addressing insufficient weight loss or weight regain following failed primary restrictive bariatric surgery. Effectiveness was measured in terms of additional weight loss. Secondary objectives included comparisons of surgical duration, reduction in obesity-related comorbidities, rates of short- and long-term complications, and mortality between the two revisional approaches. The study was conducted from January 2019 to December 2021, with a three-year follow-up for each participant.
Patient Selection and Data Collection
Participants were recruited from four high-volume bariatric centers in Italy. Inclusion criteria encompassed adults aged 18 to 65 years who exhibited insufficient weight loss, defined as excess weight loss of less than 50%, total weight loss of less than 25%, or a BMI greater than 40 kg/m² at least two years after undergoing laparoscopic sleeve gastrectomy or laparoscopic adjustable gastric banding. Eligible patients were those requiring revisional surgery exclusively for inadequate weight loss or regain. Exclusion criteria included revisional surgery for other indications (e.g., complications such as stenosis or severe gastroesophageal reflux), untreated psychiatric illness, active eating disorders, pregnancy, or any previous gastric surgery unrelated to bariatric interventions.
Preoperative assessments involved a multidisciplinary team including an endocrinologist, dietitian, and psychologist. Patients identified with maladaptive eating patterns received treatment before surgery to optimize outcomes. Baseline data on demographics, preoperative BMI, and comorbidities were collected and followed up throughout the study. Ethical approval was obtained from all participating centers' medical ethics committees.
Surgical Technique and Perioperative Management
One-Anastomosis Gastric Bypass
The surgical protocol for one-anastomosis gastric bypass involved removing the gastric band in patients previously treated with laparoscopic adjustable gastric banding, followed by dissection of the angle of His. If present, the fibrous capsule from the band was excised. A gastric pouch was created by horizontally transecting the stomach at the junction of the corpus and antrum, typically at the level of the crow's foot. For patients with a prior sleeve gastrectomy, the residual sleeve was horizontally transected. The length of the biliopancreatic limb was tailored based on the patient's preoperative BMI, ranging from 180 to 200 cm.
Roux-en-Y Gastric Bypass
For Roux-en-Y gastric bypass, the gastric band and fibrous capsule were removed in previously banded patients, followed by adhesiolysis as necessary. A small gastric pouch was created by transecting the stomach. The lengths of the alimentary and biliopancreatic limbs were standardized across centers. Closure of mesenteric defects was performed at the surgeon's discretion.
Data Collection
Type 2 Diabetes Mellitus
Type 2 diabetes mellitus was diagnosed according to established guidelines, based on fasting plasma glucose readings above 126 mg/dL, a two-hour glucose level exceeding 200 mg/dL during an oral glucose tolerance test, or a glycated hemoglobin level above 6.5%. Complete remission was defined as fasting plasma glucose levels below 100 mg/dL and HbA1c less than 6.0% without antidiabetic medications. Follow-ups were conducted at 3, 6, 12, 24, and 36 months post-revision.
Hypertension
Hypertension was defined as systolic blood pressure greater than or equal to 140 mmHg or diastolic pressure greater than or equal to 90 mmHg. Remission was defined as achieving blood pressure below 120/80 mmHg without antihypertensive medications. Blood pressure measurements were taken at 3, 6, 12, 24, and 36 months.
Obstructive Sleep Apnea Syndrome
Obstructive sleep apnea was diagnosed based on prior polysomnography, with an Apnea-Hypopnea Index exceeding 15 events/hour or more than 5 events/hour in the presence of related symptoms such as snoring or daytime sleepiness. Remission was defined by resolution of these symptoms. Follow-up assessments occurred at 3, 6, 12, 24, and 36 months.
Outcome Measures
Baseline characteristics, including demographics, preoperative BMI, and comorbidities, were recorded at study entry.
Primary Outcomes
- Percentage Total Weight Loss: Measured as the proportion of total body weight lost relative to initial weight.
- Percentage Excess BMI Loss: Calculated as the proportion of BMI lost relative to the amount exceeding a BMI of 25.
Secondary Outcomes
- Mortality: Measured throughout the three-year follow-up.
- Complications: Assessed using the Clavien-Dindo classification. Short-term complications included anastomotic leaks, bleeding, infections, perforations, myocardial infarction, and stroke. Long-term complications included nutritional deficiencies, gastric ulcers, strictures, bile reflux, internal herniation, and malnutrition.
- Comorbidity Improvement: Evaluated using standardized criteria for resolution or improvement of type 2 diabetes, cardiovascular disease, obstructive sleep apnea, dyslipidemia, and osteoarthritis.
Quality of Life Outcomes
Quality of life was assessed using validated tools such as the SF-36 at multiple intervals: baseline, and 3, 6, 12, 24, and 36 months post-surgery. Domains evaluated included physical health, mobility, social functioning, emotional well-being, and fatigue. Quality-of-life trends were compared between the two surgical groups to identify differences in patient-reported outcomes.
Study design
- Observational model
- Cohort
- Time perspective
- Retrospective
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| OAGB Cohort - Patients undergoing One-Anastomosis Gastric Bypass as a revisional procedure. | – | –OAGB Cohort: This group consists of patients who underwent One-Anastomosis Gastric Bypass (OAGB) as a revisional bariatric procedure following insufficient weight loss or weight regain after primary restrictive surgeries, such as laparoscopic sleeve gastrectomy (LSG) or laparoscopic adjustable gastric banding (LAGB). These patients were monitored over three years to evaluate outcomes, including weight loss, complication rates, and improvement in obesity-related comorbidities. |
| RYGB Cohort - Patients undergoing Roux-en-Y Gastric Bypass as a revisional procedure. | – | –RYGB Cohort: This group includes patients who underwent Roux-en-Y Gastric Bypass (RYGB) as a revisional bariatric procedure due to insufficient weight loss or significant weight regain after primary restrictive surgeries, such as laparoscopic sleeve gastrectomy (LSG) or laparoscopic adjustable gastric banding (LAGB). The cohort was followed prospectively over three years to assess outcomes, including weight loss, resolution of obesity-related comorbidities, complication rates, and overall surgical success. |
Who may qualify
- Ages
- 18 to 65 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- Study participants will be selected from a population of adults aged 18 to 65 years who have undergone primary restrictive bariatric surgery, such as laparoscopic sleeve gastrectomy (LSG) or laparoscopic adjustable gastric banding (LAGB), and have experienced insufficient weight loss or significant weight regain. This population will include individuals from multiple high-volume bariatric centers, ensuring a diverse cohort representing a range of demographic, clinical, and surgical characteristics. Eligible participants must meet specific criteria, such as a body mass index (BMI) ≤ 40 kg/m² and stable comorbid conditions. The study will focus on patients who require revisional bariatric surgery and are deemed suitable candidates for One-Anastomosis Gastric Bypass (OAGB) or Roux-en-Y Gastric Bypass (RYGB). Patients with specific contraindications, such as ongoing acute medical conditions or inability to provide informed consent, will be excluded to maintain the integrity and safety of
Key inclusion criteria (7 listed)
- Adults aged 18-65 years.
- Experienced insufficient weight loss, defined as:
- Excess weight loss (EWL) < 50%.
- Total weight loss (TWL) < 25%.
- BMI > 40 kg/m² at least two years after primary restrictive surgery.
Key exclusion criteria (4 listed)
- Revisional surgery performed for indications other than inadequate weight loss or weight regain (e.g., complications of the primary procedure such as stenosis or refractory gastroesophageal reflux, or for comorbidity management).
- Known psychiatric illness or untreated eating disorders.
- Pregnancy.
- History of prior gastric surgery unrelated to bariatric interventions.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Primary outcome
Percentage Total Weight Loss (%TWL)
Time frame: Measured at 12 months post-surgery.
The percentage of total body weight lost from the pre-revisional weight to the weight at 36 months post-revision.
Percentage Total Weight Loss (%TWL)
Time frame: Measured at 24, months post-surgery.
The percentage of total body weight lost from the pre-revisional weight to the weight at 36 months post-revision.
Percentage Total Weight Loss (%TWL)
Time frame: Measured at 36 months post-surgery.
The percentage of total body weight lost from the pre-revisional weight to the weight at 36 months post-revision.
21 secondary outcomes
Percentage Excess BMI Loss (%EBMIL)
Time frame: Measured at 12 months post-surgery
Percentage Excess BMI Loss (%EBMIL)
Time frame: Measured at 24 months post-surgery
Percentage Excess BMI Loss (%EBMIL)
Time frame: Measured at 36 months post-surgery
Reduction in Obesity-Related Comorbidities
Time frame: 36 months
Complication Rates
Time frame: until 30 days follow-up period.
Complication Rates
Time frame: 36-month follow-up period.
Mortality Rate
Time frame: 36 months post-surgery.
Quality of Life (QoL) Assessment
Time frame: Baseline
Quality of Life (QoL) Assessment
Time frame: , 12 months post-surgery
Quality of Life (QoL) Assessment
Time frame: 24, months post-surgery months post-surgery
Quality of Life (QoL) Assessment
Time frame: 36 months post-surgery, months post-surgery months post-surgery
Remission of Hypertension (HTN)
Time frame: Measured at 3, months post-revision.
Remission of Hypertension (HTN)
Time frame: Measured at 6, months post-revision.
Remission of Hypertension (HTN)
Time frame: Measured at 12, months post-revision.
Remission of Hypertension (HTN)
Time frame: Measured at 24, months post-revision.
Remission of Hypertension (HTN)
Time frame: Measured at 36, months post-revision.
Type 2 Diabetes Mellitus (T2DM)
Time frame: Assessed at 3,months post-revision
Type 2 Diabetes Mellitus (T2DM)
Time frame: Assessed at 6months post-revision
Type 2 Diabetes Mellitus (T2DM)
Time frame: Assessed at 12 months post-revision
Type 2 Diabetes Mellitus (T2DM)
Time frame: Assessed at 24 months post-revision
Type 2 Diabetes Mellitus (T2DM)
Time frame: Assessed at 36 months post-revision
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 28 Jan 2025.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
The record lists no contact. Use the official record to reach the sponsor.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Obesity, Morbid and Type 2 Diabetes Mellitus (T2DM), run by Azienda Sanitaria Locale Napoli 2 Nord at 1 site in Italy.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 7 inclusion and 4 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 28 Jan 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Italy. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Percentage Total Weight Loss (%TWL) (time frame: Measured at 12 months post-surgery.). The study lists 3 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 28 Jan 2025.