Obesity, MorbidMETABARNCT07643376
Evaluation of Metabolic Parameters, Intestinal Permeability and Gastrointestinal Symptoms After Bariatric Surgery in Body Weight Management
An observational study of Obesity, Morbid and Bariatric Surgery, run by Toros University at 1 site in Turkey (Türkiye).
Trial summary
This study aims to evaluate the changes in metabolic parameters, intestinal permeability, and gastrointestinal symptoms in individuals who have undergone bariatric surgery (Laparoscopic Sleeve Gastrectomy - LSG) for obesity treatment. Read more about this study
- Who is it for?
- Ages 19 to 50 years
- Conditions the study is for
- Obesity, Morbid, Bariatric Surgery, Intestinal Permeability
- What is being tested?
- Clinical and Biochemical Assessment
- How many people
- 40 participants
- Where
- 1 siteTurkey (Türkiye)
- Study dates
- 1 Jul 2026to 1 Feb 2027
- Phase
- Observational
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 19 to 50 years
- All sexes
- No healthy volunteers
- Adult
Study population: Adults with morbid obesity who underwent Laparoscopic Sleeve Gastrectomy (LSG) at Bursa Yıldırım Doruk Hospital General Surgery Clinic within the last month, meeting the inclusion criteria.
Who may be able to join
- Underwent Laparoscopic Sleeve Gastrectomy (LSG) within the last 1 month
- Aged between 19-50 years
- BMI ≥40 kg/m² or BMI ≥35 kg/m² with obesity-related comorbidities
- Signed informed consent form
- Non-smoker and non-alcohol dependent
Who cannot join
- Did not undergo or is not planned to undergo LSG
- Outside the age range of 19-50 years
- Did not sign the informed consent form
- BMI <40 kg/m² or BMI <35 kg/m² without obesity-related comorbidities
- Smoker or alcohol dependent
- Has an inflammatory disease
- Currently using probiotics, antibiotics, or fiber supplements
- Has a psychiatric disorder
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Turkey (Türkiye)1 site
Bursa Yıldırım Doruk Hospital
Bursa, Bursa, 16310
Doğukan DURAK;, Assoc. Prof., +905327243733, dogukandurak404@hotmail.com
Betül GÜLŞEN, Assoc. Prof., +903246253300, betul.atalay@toros.edu.tr
About this study
Official title: Evaluation of Postoperative Metabolic Parameters, Intestinal Permeability and Gastrointestinal Symptoms in Body Weight Management After Laparoscopic Sleeve Gastrectomy
This study aims to evaluate the changes in metabolic parameters, intestinal permeability, and gastrointestinal symptoms in individuals who have undergone bariatric surgery (Laparoscopic Sleeve Gastrectomy - LSG) for obesity treatment.
Obesity is a chronic disease associated with serious health complications including type 2 diabetes, hypertension, cardiovascular disease, and metabolic disorders. Bariatric surgery is currently the most effective treatment method for morbid obesity. However, monitoring patients after surgery in terms of metabolic health, gut permeability, and gastrointestinal symptoms is crucial for long-term success.
Read more
In this study, 40 volunteers (aged 19-50) who have undergone LSG surgery within the last month will be followed for 6 months. At the beginning of the study and 6 months later, the following will be assessed:
- Metabolic parameters: fasting blood glucose, total cholesterol, triglycerides, high-density lipoprotein (HDL), low-density lipoprotein (LDL), very low-density lipoprotein (VLDL) cholesterol, and insulin levels
- Intestinal permeability markers: zonulin, secretory immunoglobulin A (IgA), and lipopolysaccharide (LPS) levels
- Gastrointestinal symptoms: assessed using the Gastrointestinal Symptom Rating Scale (GSRS)
- Anthropometric measurements: body weight, height, waist and hip circumference, BMI
- Nutritional intake: 3-day dietary records
The study will be conducted at Bursa Yıldırım Doruk Hospital, General Surgery Clinic. Results will contribute to understanding the relationship between bariatric surgery and gut health, potentially helping to prevent postoperative complications.
Read the detailed description
Obesity is defined by the World Health Organization (WHO) as abnormal or excessive fat accumulation that presents a risk to health. Bariatric surgery, particularly Laparoscopic Sleeve Gastrectomy (LSG), is considered the most effective long-term treatment for morbid obesity.
This prospective observational study will be conducted at Bursa Yıldırım Doruk Hospital with 40 volunteers who have undergone LSG within the last month. Participants will be evaluated at baseline (immediately after surgery) and at 6 months post-surgery.
Assessments include:
- Anthropometric Measurements: Body weight, height, waist and hip circumference will be measured. BMI and waist-to-hip ratio will be calculated according to WHO criteria.
- Biochemical Parameters: Fasting blood glucose, total cholesterol, triglycerides, high-density lipoprotein (HDL), low-density lipoprotein (LDL), very low-density lipoprotein (VLDL) cholesterol, and insulin levels will be obtained from patient records. Zonulin, secretory immunoglobulin A (IgA), and lipopolysaccharide (LPS) levels will be analyzed using ELISA method (Biotek TS800) with commercial kits (RelAssay® Diagnostics, Ankara, Turkey) at Ankara Diagen Laboratory. Samples will be stored at -20°C until analysis.
- Gastrointestinal Symptom Rating Scale (GSRS): A validated 15-item scale assessing five dimensions: diarrhea, indigestion, constipation, abdominal pain, and reflux. Scores range from 1 (no discomfort) to 7 (very severe discomfort). Turkish validity and reliability was established by Turan and Asti (2011).
- Dietary Assessment: 3-day dietary records will be collected and analyzed using the Nutrition Information System (BeBIS) 8.2 software. Results will be evaluated according to the Turkish Dietary Guidelines 2022 (TUBER 2022).
Statistical analyses will be performed using the Statistical Package for the Social Sciences (SPSS) 22.0. Normal distribution will be assessed using Kolmogorov-Smirnov/Shapiro-Wilk tests. Results will be expressed as mean ± standard deviation for continuous variables and frequency/percentage for categorical variables.
- Conditions
- Obesity, Morbid, Bariatric Surgery, Intestinal Permeability, Gastrointestinal Symptoms, Metabolic Syndrome
- Being tested
- Clinical and Biochemical Assessment
- Keywords
- Laparoscopic Sleeve Gastrectomy, Zonulin, Secretory IgA, Lipopolysaccharide, GSRS, Body Weight Management, Gut microbiota, Postoperative Metabolic Parameters
- Medical subject headings
- Obesity, Morbid, Metabolic Syndrome
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Clinical and Biochemical AssessmentOther
Also called Anthropometric Measurement, Biochemical Blood Analysis, Gastrointestinal Symptom Rating Scale (GSRS), 3-Day Dietary Record
Participants will undergo two assessment visits: at baseline (within 1 month post-surgery) and at 6-month follow-up. Each visit includes anthropometric measurements (body weight, height, waist and hip circumference, BMI), biochemical blood analysis (fasting glucose, lipid profile, insulin, zonulin, secretory IgA, LPS), gastrointestinal symptom evaluation via GSRS, and 3-day dietary records.
| Study group | Role | What they receive |
|---|---|---|
| LSG Group | Adults aged 19-50 years who underwent Laparoscopic Sleeve Gastrectomy (LSG) within the last month at Bursa Yıldırım Doruk Hospital. Participants will be evaluated at baseline and 6 months after surgery for metabolic parameters, intestinal permeability markers, gastrointestinal symptoms, anthropometric measurements, and dietary intake. Receives: Other: Clinical and Biochemical Assessment |
What is being measured
The primary outcome is the main question the study is designed to answer.
Change in Fasting Blood Glucose Concentration (mg/dL)
Change in serum fasting blood glucose levels after 12-hour fasting between baseline and 6-month follow-up.
Measured: Baseline and 6 months
Change in Total Cholesterol Concentration (mg/dL)
Change in serum total cholesterol levels after 12-hour fasting between baseline and 6-month follow-up.
Measured: Baseline and 6 months
Change in Triglyceride Concentration (mg/dL)
Change in serum triglyceride levels after 12-hour fasting between baseline and 6-month follow-up.
Measured: Baseline and 6 months
Change in HDL Cholesterol Concentration (mg/dL)
Change in serum high-density lipoprotein (HDL) cholesterol levels after 12-hour fasting between baseline and 6-month follow-up.
Measured: Baseline and 6 months
Change in LDL Cholesterol Concentration (mg/dL)
Change in serum low-density lipoprotein (LDL) cholesterol levels after 12-hour fasting between baseline and 6-month follow-up.
Measured: Baseline and 6 months
Change in VLDL Cholesterol Concentration (mg/dL)
Change in serum very low-density lipoprotein (VLDL) cholesterol levels after 12-hour fasting between baseline and 6-month follow-up.
Measured: Baseline and 6 months
Change in Fasting Insulin Concentration (µIU/mL)
Change in serum fasting insulin levels after 12-hour fasting between baseline and 6-month follow-up.
Measured: Baseline and 6 months
Change in Serum Zonulin Concentration (ng/mL)
Change in serum zonulin levels assessed by ELISA method between baseline and 6-month follow-up.
Measured: Baseline and 6 months
Change in Serum Secretory IgA Concentration (mg/dL)
Change in serum secretory IgA levels assessed by ELISA method between baseline and 6-month follow-up.
Measured: Baseline and 6 months
Change in Serum LPS Concentration (EU/mL)
Change in serum lipopolysaccharide (LPS) levels assessed by ELISA method between baseline and 6-month follow-up.
Measured: Baseline and 6 months
Change in Gastrointestinal Symptom Rating Scale (GSRS) Total Score (1-7)
Change in total score of the Gastrointestinal Symptom Rating Scale (GSRS) between baseline and 6-month follow-up. The scale consists of 15 items across 5 subscales; scores range from 1 to 7, with higher scores indicating more severe gastrointestinal symptoms.
Measured: Baseline and 6 months
Secondary outcomes (9)
Change in Body Weight (kg)
Change in body weight between baseline and 6-month follow-up.
Measured: Baseline and 6 months
Change in Body Mass Index (kg/m²)
Change in BMI between baseline and 6-month follow-up. Weight and height will be combined to report BMI in kg/m².
Measured: Baseline and 6 months
Change in Waist Circumference (cm)
Change in waist circumference between baseline and 6-month follow-up.
Measured: Baseline and 6 months
Change in Hip Circumference (cm)
Change in hip circumference between baseline and 6-month follow-up.
Measured: Baseline and 6 months
Change in Waist-to-Hip Ratio
Change in waist-to-hip ratio between baseline and 6-month follow-up. Waist and hip circumference measurements will be combined to calculate the waist-to-hip ratio.
Measured: Baseline and 6 months
Change in Daily Energy Intake (kcal/day)
Change in daily energy intake assessed by 3-day dietary intake records between baseline and 6-month follow-up. Data will be analyzed using BeBIS 8.2 software.
Measured: Baseline and 6 months
Change in Daily Protein Intake (g/day)
Change in daily protein intake assessed by 3-day dietary intake records between baseline and 6-month follow-up. Data will be analyzed using BeBIS 8.2 software.
Measured: Baseline and 6 months
Change in Daily Carbohydrate Intake (g/day)
Change in daily carbohydrate intake assessed by 3-day dietary intake records between baseline and 6-month follow-up. Data will be analyzed using BeBIS 8.2 software.
Measured: Baseline and 6 months
Change in Daily Fat Intake (g/day)
Change in daily fat intake assessed by 3-day dietary intake records between baseline and 6-month follow-up. Data will be analyzed using BeBIS 8.2 software.
Measured: Baseline and 6 months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted11 Jun 2026
- Study start1 Jul 2026 (estimated)
- Primary completion1 Jan 2027 (estimated)
- Study completion1 Feb 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (29)Papers the sponsor has linked to this study.
- 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
- Prospective
- Enrolment
- 40 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Toros University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Betül Gülşen, Toros University
- Investigators
- Betül GÜLŞEN, Assoc. Prof., Principal investigator, Toros UniversityÖzlem ÖZPAK AKKUŞ, Assoc. Prof., Study chair, Toros UniversityDoğukan DURAK, Assoc. Prof., Study director, Bursa Yıldırım Doruk Hospital, General Surgery Clinic
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07643376
- Sponsor's protocol ID
- BCKLY-BGP-2026
- Acronym
- METABAR
- Status last verified
- May 2026
- First submitted
- 20 May 2026
- Last updated
- 11 Jun 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 ethical considerations and participant confidentiality. Data will be stored securely and used only for the purposes of this study in accordance with Turkish Personal Data Protection Law (KVKK) and the ethical approval pending from Toros University Faculty of Health Sciences Non-Interventional Clinical Research Ethics Committee.
Publications
Revicki DA, Wood M, Wiklund I, Crawley J. Reliability and validity of the Gastrointestinal Symptom Rating Scale in patients with gastroesophageal reflux disease. Qual Life Res. 1998 Jan;7(1):75-83. doi: 10.1023/a:1008841022998.
PubMed 9481153Debedat J, Clement K, Aron-Wisnewsky J. Gut Microbiota Dysbiosis in Human Obesity: Impact of Bariatric Surgery. Curr Obes Rep. 2019 Sep;8(3):229-242. doi: 10.1007/s13679-019-00351-3.
PubMed 31197613Khanna S, Tosh PK. A clinician's primer on the role of the microbiome in human health and disease. Mayo Clin Proc. 2014 Jan;89(1):107-14. doi: 10.1016/j.mayocp.2013.10.011.
PubMed 24388028Kalarchian MA, King WC, Devlin MJ, White GE, Marcus MD, Garcia L, Yanovski SZ, Mitchell JE. Surgery-related gastrointestinal symptoms in a prospective study of bariatric surgery patients: 3-year follow-up. Surg Obes Relat Dis. 2017 Sep;13(9):1562-1571. doi: 10.1016/j.soard.2017.03.028. Epub 2017 Apr 4.
PubMed 28579205Poves I, Cabrera M, Maristany C, Coma A, Ballesta-Lopez C. Gastrointestinal quality of life after laparoscopic Roux-en-Y gastric bypass. Obes Surg. 2006 Jan;16(1):19-23. doi: 10.1381/096089206775222032.
PubMed 16417752Karlsson J, Taft C, Ryden A, Sjostrom L, Sullivan M. Ten-year trends in health-related quality of life after surgical and conventional treatment for severe obesity: the SOS intervention study. Int J Obes (Lond). 2007 Aug;31(8):1248-61. doi: 10.1038/sj.ijo.0803573. Epub 2007 Mar 13.
PubMed 17356530Buchwald H, Avidor Y, Braunwald E, Jensen MD, Pories W, Fahrbach K, Schoelles K. Bariatric surgery: a systematic review and meta-analysis. JAMA. 2004 Oct 13;292(14):1724-37. doi: 10.1001/jama.292.14.1724.
PubMed 15479938Turan N, Ast TA, Kaya N. Reliability and Validity of the Turkish Version of the Gastrointestinal Symptom Rating Scale. Gastroenterol Nurs. 2017 Jan/Feb;40(1):47-55. doi: 10.1097/SGA.0000000000000177.
PubMed 28134719Pekcan G, Şanlıer N, Baş M, Acar Tek N, Gökmen Özel H. Türkiye Beslenme Rehberi (TÜBER) 2022. Ankara: Hazar Reklamcılık; 2022.
Beslenme Bilgi Sistemleri Paket Programı (BeBIS 8.2). İstanbul: Software NDB; 2015.
Merdol TK. Toplu Beslenme Yapılan Kurumlar için Standart Yemek Tarifleri. Hatipoğlu Yayınları; 2003.
Rakıcıoğlu N, Tek NA, Ayaz A, Pekcan G. Yemek ve Besin Fotoğraf Kataloğu Ölçü ve Miktarlar. Nadir Kitap; 2012.
Physical status: the use and interpretation of anthropometry. Report of a WHO Expert Committee. World Health Organ Tech Rep Ser. 1995;854:1-452.
PubMed 8594834Pekcan G. Beslenme durumunun saptanması. Diyet El Kitabı. Ankara: Hatipoğlu Yayınevi; 2013:67-142.
Kuyucu A. Bariatrik cerrahi uygulanmış hastaların ameliyat sonrası altı ay ve üzeri sürede vücut ağırlığı kaybının, besin tüketim durumunun ve bazı biyokimyasal bulgularının belirlenmesi. Yüksek Lisans Tezi. Gaziantep: Hasan Kalyoncu Üniversitesi Sağlık Bilimleri Enstitüsü; 2018.