Sleeve GastrectomyNCT07348822
8-Year Outcomes After Sleeve Gastrectomy
An observational study of Sleeve Gastrectomy and Obesity & Overweight, run by Medipol University at 1 site in Turkey (Türkiye).
Trial summary
Obesity is a major global public health concern, and bariatric surgery is recognized as the most effective treatment for achieving sustained weight loss and improving obesity-related comorbidities. Read more about this study
- Who is it for?
- Ages 18 to 65 years
- Conditions the study is for
- Sleeve Gastrectomy, Obesity & Overweight
- How many people
- 20 participants
- Where
- 1 siteTurkey (Türkiye)
- Study dates
- 12 Jun 2025to 10 Mar 2026
- Phase
- Observational
- Are there results?
- Not yet: the study is under way
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: The study population includes adults aged 18-65 years who underwent sleeve gastrectomy approximately eight years prior to enrollment and completed standard postoperative follow-up. Participants had available preoperative and 6-month postoperative anthropometric, biochemical, and nutritional data and were re-evaluated at 8 years after surgery to assess long-term outcomes.
Who may be able to join
- Adults aged 18-65 years
- Patients who underwent sleeve gastrectomy approximately 8 years prior to study enrollment
- Patients with available postoperative follow-up data at 6 months, including anthropometric measurements, biochemical parameters, and nutritional status assessments
- Patients willing to participate in long-term follow-up and attend in-person evaluations
Who cannot join
- Pregnancy or lactation
- Presence of acute illness or active infection at the time of evaluation
- Presence of acute illness, infection, or comorbid conditions that may limit study safety or validity, including malignancy, type 1 diabetes mellitus, renal or hepatic failure, recent stroke or myocardial infarction, nephrolithiasis, drug or alcohol abuse, eating disorders, severe depression or other major psychiatric disorders, inflammatory bowel disease, cardiac arrhythmias or heart failure, respiratory failure, or chronic systemic corticosteroid therapy.
- Professional athletes
Trial locations and contacts
1 site in 1 country.
About this study
Official title: 8-Year Outcomes After Sleeve Gastrectomy: Anthropometric, Biochemical, and Nutritional Evaluation
Obesity is a major global public health concern, and bariatric surgery is recognized as the most effective treatment for achieving sustained weight loss and improving obesity-related comorbidities. Sleeve gastrectomy (SG) is one of the most commonly performed bariatric procedures; however, long-term outcomes vary considerably among individuals. While some patients maintain satisfactory weight loss, others experience suboptimal weight loss or weight regain several years after surgery. Evidence suggests that long-term weight trajectories after SG may be influenced by metabolic changes, dietary habits, and lifestyle factors, highlighting the need for extended follow-up studies.
This observational cohort study aims to evaluate the long-term outcomes of individuals who underwent sleeve gastrectomy approximately 8 years ago. Anthropometric measurements, biochemical parameters, and nutritional status will be reassessed at an 8-year follow-up visit and compared with data obtained during the preoperative period and at postoperative 6 months. By examining within-subject changes over time, this study seeks to provide insight into the long-term sustainability of weight loss after sleeve gastrectomy and to identify metabolic and nutritional factors associated with long-term outcomes.
- Conditions
- Sleeve Gastrectomy, Obesity & Overweight
- Keywords
- long-term follow-up, sleeve gastrectomy, obesity, metabolic outcomes, nutritional status, anthropometric measurements
- Medical subject headings
- Obesity, Overweight
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 |
|---|---|---|
| Sleeve Gastrectomy Long-Term Follow-up Cohort | This cohort includes adults who underwent sleeve gastrectomy between 2016 and 2017 and were re-evaluated approximately 8 years after surgery. Participants are followed observationally, with anthropometric measurements, biochemical parameters, and nutritional status assessed preoperatively, at postoperative 6 months, and at long-term (8-year) follow-up. No intervention is assigned as part of the study protocol; all surgical procedures were performed as part of routine clinical care. |
What is being measured
The primary outcome is the main question the study is designed to answer.
Change in Fat Mass
Changes in fat mass measured using multi-frequency bioelectrical impedance analysis (BIA).
Measured: Preoperative, postoperative 6 months, and postoperative 8 years
Change in Body Weight
Body weight measured using a calibrated digital scale with participants wearing light clothing and no shoes.
Measured: Preoperative, postoperative 6 months, and postoperative 8 years
Change in Body Mass Index (BMI)
BMI calculated as weight in kilograms divided by height in meters squared (kg/m²), measured using a wall-mounted stadiometer.
Measured: Preoperative, postoperative 6 months, and postoperative 8 years
Change in Waist Circumference
Waist circumference measured in centimeters at the midpoint between the subcostal margin and the iliac crest with participants standing upright.
Measured: Preoperative, postoperative 6 months, and postoperative 8 years
Change in Hip Circumference
Hip circumference measured in centimeters at the level of maximum gluteal protrusion.
Measured: Preoperative, postoperative 6 months, and postoperative 8 years
Percent Total Weight Loss (TWL%)
Calculated as [(preoperative weight - postoperative weight) / preoperative weight] × 100.
Measured: Postoperative 6 months and postoperative 8 years
Percent Excess Weight Loss (EWL%)
Calculated as [(preoperative weight - postoperative weight) / (preoperative weight - ideal body weight)] × 100, where ideal body weight corresponds to a BMI of 25 kg/m².
Measured: Postoperative 6 months and postoperative 8 years
Change in Body Fat Percentage
Changes in body fat percentage measured using multi-frequency bioelectrical impedance analysis (BIA).
Measured: Preoperative baseline, postoperative 6 months, and postoperative 8 years
Change in Skeletal Muscle Mass
Changes in skeletal muscle mass measured using multi-frequency bioelectrical impedance analysis (BIA).
Measured: Preoperative baseline, postoperative 6 months, and postoperative 8 years
Secondary outcomes (15)
Change in Fasting Plasma Glucose
Fasting plasma glucose measured after at least 8 hours of fasting using venous blood samples.
Measured: Preoperative, postoperative 6 months, and postoperative 8 years
Change in Fasting Insulin Levels
Fasting insulin levels measured from venous blood samples obtained after at least 8 hours of fasting.
Measured: Preoperative, postoperative 6 months, and postoperative 8 years
Change in Glycated Hemoglobin (HbA1c)
HbA1c levels measured to assess long-term glycemic control.
Measured: Preoperative, postoperative 6 months, and postoperative 8 years
Change in Lipid Profile Parameters
Serum lipid parameters including total cholesterol, LDL cholesterol, HDL cholesterol, and triglycerides measured after an overnight fast.
Measured: Preoperative, postoperative 6 months, and postoperative 8 years
Change in Liver Enzyme Levels
Serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels measured from fasting blood samples.
Measured: Preoperative, postoperative 6 months, and postoperative 8 years
Change in Renal and Metabolic Biomarkers
Serum urea and uric acid levels measured to assess renal and metabolic function.
Measured: Preoperative, postoperative 6 months, and postoperative 8 years
Change in Serum Albumin
Changes in serum albumin levels measured from venous blood samples.
Measured: Preoperative, postoperative 6 months, and postoperative 8 years
Change in Micronutrient Levels
Serum levels of vitamin B12, folic acid, magnesium, total calcium, sodium, and potassium measured to assess micronutrient status.
Measured: Preoperative, postoperative 6 months, and postoperative 8 years
Change in Physical Activity Level
Physical activity levels assessed using the International Physical Activity Questionnaire (IPAQ).
Measured: Preoperative, postoperative 6 months, and postoperative 8 years
Change in Fat-Free Mass
Changes in fat-free mass measured using multi-frequency bioelectrical impedance analysis (BIA).
Measured: Preoperative baseline, postoperative 6 months, and postoperative 8 years
Change in Total Protein
Changes in total serum protein levels measured from venous blood samples.
Measured: Preoperative baseline, postoperative 6 months, and postoperative 8 years
Change in Hemoglobin
Changes in hemoglobin levels measured from venous blood samples.
Measured: Preoperative baseline, postoperative 6 months, and postoperative 8 years
Change in Hematocrit
Changes in hematocrit levels measured from venous blood samples.
Measured: Preoperative baseline, postoperative 6 months, and postoperative 8 years
Change in Serum Ferritin
Changes in serum ferritin levels measured from venous blood samples.
Measured: Preoperative baseline, postoperative 6 months, and postoperative 8 years
Change in Serum Iron
Changes in serum iron levels measured from venous blood samples.
Measured: Preoperative baseline, postoperative 6 months, and postoperative 8 years
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted16 Jan 2026
- Study start12 Jun 2025
- Primary completion10 Jan 2026
- Study completion10 Mar 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Sleeve GastrectomyStudies 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
- Prospective
- Enrolment
- 20 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Medipol University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Seher Şen, Medipol University
- Investigators
- Seher Şen, Study director, Mudanya University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07348822
- Sponsor's protocol ID
- MUDU-SBE-SS-02
- Status last verified
- Feb 2026
- First submitted
- 18 Dec 2025
- Last updated
- 3 Feb 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No: Individual participant data will not be shared due to the need to protect patient privacy and confidentiality. T
Study at a glance
From the registry record, last updated by the sponsor on 3 Feb 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- 8-Year Outcomes After Sleeve Gastrectomy: Anthropometric, Biochemical, and Nutritional Evaluation
- ClinicalTrials.gov ID
- NCT07348822
- Acronym / sponsor ID
- MUDU-SBE-SS-02
- Conditions
- Sleeve Gastrectomy, Obesity & Overweight
- Keywords
- long-term follow-up, sleeve gastrectomy, obesity, metabolic outcomes, nutritional status, anthropometric measurements
- Study type
- Observational
- Recruitment status
- Active, not recruiting
- Enrolment
- 20 participants (estimated)
- Lead sponsor
- Medipol UniversityUniversity, hospital or other
- Study start
- 12 Jun 2025 (actual)
- Primary completion
- 10 Jan 2026 (actual)
- Study completion
- 10 Mar 2026 (estimated)
- First posted
- 16 Jan 2026 (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.
Obesity is a major global public health concern, and bariatric surgery is recognized as the most effective treatment for achieving sustained weight loss and improving obesity-related comorbidities. Sleeve gastrectomy (SG) is one of the most commonly performed bariatric procedures; however, long-term outcomes vary considerably among individuals. While some patients maintain satisfactory weight loss, others experience suboptimal weight loss or weight regain several years after surgery. Evidence suggests that long-term weight trajectories after SG may be influenced by metabolic changes, dietary habits, and lifestyle factors, highlighting the need for extended follow-up studies.
This observational cohort study aims to evaluate the long-term outcomes of individuals who underwent sleeve gastrectomy approximately 8 years ago. Anthropometric measurements, biochemical parameters, and nutritional status will be reassessed at an 8-year follow-up visit and compared with data obtained during the preoperative period and at postoperative 6 months. By examining within-subject changes over time, this study seeks to provide insight into the long-term sustainability of weight loss after sleeve gastrectomy and to identify metabolic and nutritional factors associated with long-term outcomes.
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Sleeve Gastrectomy Long-Term Follow-up Cohort | – | –This cohort includes adults who underwent sleeve gastrectomy between 2016 and 2017 and were re-evaluated approximately 8 years after surgery. Participants are followed observationally, with anthropometric measurements, biochemical parameters, and nutritional status assessed preoperatively, at postoperative 6 months, and at long-term (8-year) follow-up. No intervention is assigned as part of the study protocol; all surgical procedures were performed as part of routine clinical care. |
Who may qualify
- Ages
- 18 to 65 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- The study population includes adults aged 18-65 years who underwent sleeve gastrectomy approximately eight years prior to enrollment and completed standard postoperative follow-up. Participants had available preoperative and 6-month postoperative anthropometric, biochemical, and nutritional data and were re-evaluated at 8 years after surgery to assess long-term outcomes.
Key inclusion criteria (4 listed)
- Adults aged 18-65 years
- Patients who underwent sleeve gastrectomy approximately 8 years prior to study enrollment
- Patients with available postoperative follow-up data at 6 months, including anthropometric measurements, biochemical parameters, and nutritional status assessments
- Patients willing to participate in long-term follow-up and attend in-person evaluations
Key exclusion criteria (4 listed)
- Pregnancy or lactation
- Presence of acute illness or active infection at the time of evaluation
- Presence of acute illness, infection, or comorbid conditions that may limit study safety or validity, including malignancy, type 1 diabetes mellitus, renal or hepatic failure, recent stroke or myocardial infarction, nephrolithiasis, drug or alcohol abuse, eating disorders, severe depression or other major psychiatric disorders, inflammatory bowel disease, cardiac arrhythmias or heart failure, respiratory failure, or chronic systemic corticosteroid therapy.
- Professional athletes
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
Change in Fat Mass
Time frame: Preoperative, postoperative 6 months, and postoperative 8 years
Changes in fat mass measured using multi-frequency bioelectrical impedance analysis (BIA).
Change in Body Weight
Time frame: Preoperative, postoperative 6 months, and postoperative 8 years
Body weight measured using a calibrated digital scale with participants wearing light clothing and no shoes.
Change in Body Mass Index (BMI)
Time frame: Preoperative, postoperative 6 months, and postoperative 8 years
BMI calculated as weight in kilograms divided by height in meters squared (kg/m²), measured using a wall-mounted stadiometer.
Change in Waist Circumference
Time frame: Preoperative, postoperative 6 months, and postoperative 8 years
Waist circumference measured in centimeters at the midpoint between the subcostal margin and the iliac crest with participants standing upright.
Change in Hip Circumference
Time frame: Preoperative, postoperative 6 months, and postoperative 8 years
Hip circumference measured in centimeters at the level of maximum gluteal protrusion.
Percent Total Weight Loss (TWL%)
Time frame: Postoperative 6 months and postoperative 8 years
Calculated as [(preoperative weight - postoperative weight) / preoperative weight] × 100.
Percent Excess Weight Loss (EWL%)
Time frame: Postoperative 6 months and postoperative 8 years
Calculated as [(preoperative weight - postoperative weight) / (preoperative weight - ideal body weight)] × 100, where ideal body weight corresponds to a BMI of 25 kg/m².
Change in Body Fat Percentage
Time frame: Preoperative baseline, postoperative 6 months, and postoperative 8 years
Changes in body fat percentage measured using multi-frequency bioelectrical impedance analysis (BIA).
Change in Skeletal Muscle Mass
Time frame: Preoperative baseline, postoperative 6 months, and postoperative 8 years
Changes in skeletal muscle mass measured using multi-frequency bioelectrical impedance analysis (BIA).
15 secondary outcomes
Change in Fasting Plasma Glucose
Time frame: Preoperative, postoperative 6 months, and postoperative 8 years
Change in Fasting Insulin Levels
Time frame: Preoperative, postoperative 6 months, and postoperative 8 years
Change in Glycated Hemoglobin (HbA1c)
Time frame: Preoperative, postoperative 6 months, and postoperative 8 years
Change in Lipid Profile Parameters
Time frame: Preoperative, postoperative 6 months, and postoperative 8 years
Change in Liver Enzyme Levels
Time frame: Preoperative, postoperative 6 months, and postoperative 8 years
Change in Renal and Metabolic Biomarkers
Time frame: Preoperative, postoperative 6 months, and postoperative 8 years
Change in Serum Albumin
Time frame: Preoperative, postoperative 6 months, and postoperative 8 years
Change in Micronutrient Levels
Time frame: Preoperative, postoperative 6 months, and postoperative 8 years
Change in Physical Activity Level
Time frame: Preoperative, postoperative 6 months, and postoperative 8 years
Change in Fat-Free Mass
Time frame: Preoperative baseline, postoperative 6 months, and postoperative 8 years
Change in Total Protein
Time frame: Preoperative baseline, postoperative 6 months, and postoperative 8 years
Change in Hemoglobin
Time frame: Preoperative baseline, postoperative 6 months, and postoperative 8 years
Change in Hematocrit
Time frame: Preoperative baseline, postoperative 6 months, and postoperative 8 years
Change in Serum Ferritin
Time frame: Preoperative baseline, postoperative 6 months, and postoperative 8 years
Change in Serum Iron
Time frame: Preoperative baseline, postoperative 6 months, and postoperative 8 years
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 3 Feb 2026.
- Individual participant dataSharing planned: No. Individual participant data will not be shared due to the need to protect patient privacy and confidentiality. T
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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.
Seher Şen study director
Mudanya University
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 Sleeve Gastrectomy and Obesity & Overweight, run by Medipol University at 1 site in Turkey (Türkiye).
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 4 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: under way, not looking for participants, as of the sponsor's last update on 3 Feb 2026. 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 Turkey (Türkiye). 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?
This study is still under way. Results are not available in the source record yet.
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?
Change in Fat Mass (time frame: Preoperative, postoperative 6 months, and postoperative 8 years). The study lists 9 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 3 Feb 2026; AzTrials last refreshed its copy on 26 Oct 2026.