Eating Behavior, Nutritional Status and Appetite Hormones After Bariatric Surgery (BCKYL-YDB)

Evaluation of Changes in Postoperative Eating Behavior Attitudes, Nutritional Status, and Some Hormonal Parameters Regulating Appetite in Surgical Weight Management

This study aims to evaluate changes in eating behavior attitudes, nutritional status, and appetite-regulating hormonal parameters in individuals who have undergone Laparoscopic Sleeve Gastrectomy (LSG). The study will be conducted at Bursa Yıldırım Doruk Hospital, Department of General Surgery. A total of 40 volunteer participants who underwent LSG within the last month will be included. Participants will be assessed at baseline (shortly after surgery) and at 6-month follow-up. Assessments will include anthropometric measurements (body weight, height, waist and hip circumference, BMI, waist-to-hip ratio), 3-day dietary intake records analyzed using BeBIS 8.2 software, and the Adult Eating Behavior Scale. Biochemical parameters including fasting blood glucose, total cholesterol, triglycerides, HDL, LDL, VLDL cholesterol, and insulin will be obtained from patient files and analyzed using Advia Chemistry 2400 and Advia XPT devices. Additionally, appetite-regulating hormones (ghrelin, GLP-1, PYY) will be analyzed from residual blood samples using the ELISA method with RelAssay Diagnostics kits by Teknogen Bioengineering Laboratory. All data will be compared between baseline and 6-month follow-up to evaluate the impact of bariatric surgery on nutritional and hormonal outcomes.

Study Overview

• Status: Not yet recruiting
• Conditions: Obesity; Nutritional Status; Eating Behavior; Bariatric Surgery; Laparoscopic Sleeve Gastrectomy
• Intervention / Treatment: Other: Anthropometric Measurements and Dietary Assessment

Detailed Description

This observational study will be conducted at Bursa Yıldırım Doruk Hospital, General Surgery Clinic, under the supervision of Assoc. Prof. Dogukan Durak. Forty volunteer participants who underwent Laparoscopic Sleeve Gastrectomy (LSG) within the last month and meet the inclusion and exclusion criteria will be enrolled after signing an informed consent form.

Assessments will be performed at two time points: at baseline (shortly after surgery) and at 6-month follow-up.

Anthropometric Measurements: Body weight, height, waist and hip circumference will be measured. BMI and waist-to-hip ratio will be calculated accordingly. Waist circumference will be evaluated according to WHO criteria.

Dietary Assessment: A 3-day dietary intake record will be collected from each participant at both time points. Food portion sizes will be estimated using the "Food and Nutrient Photo Catalog." Energy and macronutrient intake will be analyzed using BeBIS 8.2 software and evaluated according to the Turkish Dietary Guidelines 2022 (TUBER 2022).

Eating Behavior Assessment: The Adult Eating Behavior Scale (developed by Celik et al.) will be administered at both time points. The scale consists of 18 items and 5 subscales, scored between 0-100. Higher scores indicate more positive attitudes toward eating behavior.

Biochemical and Hormonal Parameters: After 12-hour fasting, the following biochemical parameters will be obtained from patient files: fasting blood glucose (FBG), total cholesterol (TC), triglycerides (TG), high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol, very low-density lipoprotein (VLDL) cholesterol, and insulin. Routine biochemical parameters and lipid profile will be analyzed spectrophotometrically using the Advia Chemistry 2400 device, while insulin will be measured by chemiluminescence using the Advia XPT device. Additionally, appetite-regulating hormones including ghrelin, glucagon-like peptide-1 (GLP-1), and peptide YY (PYY) will be analyzed from residual blood samples stored at -20°C by Teknogen Bioengineering Laboratory using the ELISA method with an automated microplate reader (Biotek TS800) and RelAssay Diagnostics commercial kits (Ankara, Turkey).

All data will be compared between baseline and 6-month follow-up using appropriate statistical methods.

• Study Type: Observational
• Enrollment (Estimated): 40

Contacts and Locations

• Study Contact: Name: Özlem ÖZPAK AKKUŞ, Assoc. Prof.; Phone Number: +903246253300; Email: dytozlemozpak@hotmail.com
• Study Contact Backup: Name: Doğukan DURAK, Assoc. Prof.; Phone Number: +905327243733; Email: dogukandurak404@hotmail.com

Study Locations

• Turkey (Türkiye)
  • Bursa
    • Bursa, Bursa, Turkey (Türkiye), 16130
      • Bursa Yıldırım Doruk Hastanesi, General Surgery Clinic
      • Contact: Özlem ÖZPAK AKKUŞ, Assoc. Prof.; Phone Number: +903246253300; Email: dytozlemozpak@hotmail.com
      • Contact: Doğukan DURAK, Assoc. Prof.; Phone Number: +905327243733; Email: dogukandurak404@hotmail.com
      • Principal Investigator: Özlem ÖZPAK AKKUŞ, Assoc. Prof.
      • Sub-Investigator: Doğukan Durak, Assoc. Prof.
      • Sub-Investigator: Seher ŞEN, Asst. Prof.
      • Sub-Investigator: Tuğçe Nur DOĞANAY YILDIRIM, MSc, RD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Adult patients who underwent Laparoscopic Sleeve Gastrectomy (LSG) within the last month at Bursa Yıldırım Doruk Hospital, General Surgery Clinic, under the supervision of Assoc. Prof. Dogukan Durak, and who meet the inclusion and exclusion criteria.

Description

Inclusion Criteria:

• Having undergone Laparoscopic Sleeve Gastrectomy (LSG) within the last month
• Aged between 18-50 years
• Signing the informed consent form
• Having a Body Mass Index (BMI) of 40 kg/m2 or between 35-40 kg/m2 with obesity-related comorbidities
• No diagnosis of depression
• No eating behavior disorder
• No psychiatric disorder

Exclusion Criteria:

• Not having undergone Laparoscopic Sleeve Gastrectomy (LSG) or not planning to undergo bariatric surgery
• Not being in the age range of 18-50 years
• Not signing the informed consent form
• Having a Body Mass Index (BMI) greater than 40 kg/m2 or less than 35 kg/m2 without obesity-related comorbidities
• Having a diagnosis of depression
• Having an eating behavior disorder
• Having a psychiatric disorder

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort

Intervention / Treatment

LSG Patients; Individuals who underwent Laparoscopic Sleeve Gastrectomy (LSG) within the last month at Bursa Yıldırım Doruk Hospital, General Surgery Clinic, and meet the inclusion and exclusion criteria. Participants will be assessed at baseline (shortly after surgery) and at 6-month follow-up.

Other: Anthropometric Measurements and Dietary Assessment; Anthropometric measurements (body weight, height, waist and hip circumference, BMI, waist-to-hip ratio), 3-day dietary intake records, Adult Eating Behavior Scale, and biochemical and hormonal parameters (fasting blood glucose, lipid profile, insulin, ghrelin, GLP-1, PYY) will be assessed at baseline and at 6-month follow-up.; Other Names: Biochemical and Hormonal Parameter Analysis; Adult Eating Behavior Scale; 3-Day Dietary Intake Record

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Serum Ghrelin Concentration (pg/mL)	Change in serum ghrelin levels between baseline and 6-month follow-up, assessed by ELISA method.	Baseline and 6 months after surgery
Change in Serum GLP-1 Concentration (pmol/L)	Change in serum glucagon-like peptide-1 (GLP-1) levels between baseline and 6-month follow-up, assessed by ELISA method.	Baseline and 6 months after surgery
Change in Serum PYY Concentration (pg/mL)	Change in serum peptide YY (PYY) levels between baseline and 6-month follow-up, assessed by ELISA method.	Baseline and 6 months after surgery
Change in Adult Eating Behavior Scale Total Score (0-100)	Change in Adult Eating Behavior Scale total score between baseline and 6-month follow-up. Scale is scored between 0-100; higher scores indicate more positive eating behavior attitudes.	Baseline and 6 months after surgery
Change in Daily Energy Intake (kcal/day)	Change in daily energy intake assessed by 3-day dietary intake records at baseline and 6-month follow-up. Food portions will be estimated using the Food and Nutrient Photo Catalog. Data will be analyzed using BeBIS 8.2 software and evaluated according to Turkish Dietary Guidelines 2022.	Baseline and 6 months after surgery
Change in Daily Protein Intake (g/day)	Change in daily protein intake assessed by 3-day dietary intake records at baseline and 6-month follow-up. Food portions will be estimated using the Food and Nutrient Photo Catalog. Data will be analyzed using BeBIS 8.2 software and evaluated according to Turkish Dietary Guidelines 2022	Baseline and 6 months after surgery
Change in Daily Carbohydrate Intake (g/day)	Change in daily carbohydrate intake assessed by 3-day dietary intake records at baseline and 6-month follow-up. Food portions will be estimated using the Food and Nutrient Photo Catalog. Data will be analyzed using BeBIS 8.2 software and evaluated according to Turkish Dietary Guidelines 2022.	Baseline and 6 months after surgery
Change in Daily Fat Intake (g/day)	Change in daily fat intake assessed by 3-day dietary intake records at baseline and 6-month follow-up. Food portions will be estimated using the Food and Nutrient Photo Catalog. Data will be analyzed using BeBIS 8.2 software and evaluated according to Turkish Dietary Guidelines 2022.	Baseline and 6 months after surgery

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Body Weight (kg)	Change in body weight between baseline and 6-month follow-up.	Baseline and 6 months after surgery
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.	Baseline and 6 months after surgery
Change in Waist Circumference (cm)	Change in waist circumference between baseline and 6-month follow-up.	Baseline and 6 months after surgery
Change in Hip Circumference (cm)	Change in hip circumference between baseline and 6-month follow-up.	Baseline and 6 months after surgery
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.	Baseline and 6 months after surgery
Change in Fasting Blood Glucose Concentration (mg/dL)	Change in fasting blood glucose levels between baseline and 6-month follow-up.	Baseline and 6 months after surgery
Change in Total Cholesterol Concentration (mg/dL)	Change in total cholesterol levels between baseline and 6-month follow-up.	Baseline and 6 months after surgery
Change in Triglyceride Concentration (mg/dL)	Change in triglyceride levels between baseline and 6-month follow-up.	Baseline and 6 months after surgery
Change in HDL Cholesterol Concentration (mg/dL)	Change in high-density lipoprotein (HDL) cholesterol levels between baseline and 6-month follow-up.	Baseline and 6 months after surgery
Change in LDL Cholesterol Concentration (mg/dL)	Change in low-density lipoprotein (LDL) cholesterol levels between baseline and 6-month follow-up.	Baseline and 6 months after surgery
Change in VLDL Cholesterol Concentration (mg/dL)	Change in very low-density lipoprotein (VLDL) cholesterol levels between baseline and 6-month follow-up.	Baseline and 6 months after surgery
Change in Fasting Insulin Concentration (µIU/mL)	Change in fasting insulin levels between baseline and 6-month follow-up.	Baseline and 6 months after surgery

Collaborators and Investigators

• Sponsor: Özlem ÖZPAK AKKUŞ
• Investigators: Principal Investigator: Özlem ÖZPAK AKKUŞ, Assoc. Prof., Toros University

Publications and helpful links

General Publications

• Physical status: the use and interpretation of anthropometry. Report of a WHO Expert Committee. World Health Organ Tech Rep Ser. 1995;854:1-452.
• Sherf Dagan S, Goldenshluger A, Globus I, Schweiger C, Kessler Y, Kowen Sandbank G, Ben-Porat T, Sinai T. Nutritional Recommendations for Adult Bariatric Surgery Patients: Clinical Practice. Adv Nutr. 2017 Mar 15;8(2):382-394. doi: 10.3945/an.116.014258. Print 2017 Mar.
• Celik E, Karabulut E, Bilgic P. Bariatrik Cerrahi Hastalarinda Beslenme ve Davranis Tutumu Olcegi. Bes Diy Derg. 2017;45(2):107-15.
• Pekcan G, Sanlier N, Bas M, Acar Tek N, Gokmen Ozel H. Turkiye Beslenme Rehberi (TUBER) 2022. Ankara: Hazar Reklamcilik; 2022.
• Beslenme Bilgi Sistemleri Paket Programi (BeBIS 8.2). Istanbul: Software NDB; 2015.
• Merdol TK. Toplu Beslenme Yapilan Kurumlar icin Standard Yemek Tarifleri. Hatipoglu Yayinlari; 2003.
• Rakicioglu N, Tek NA, Ayaz A, Pekcan G. Yemek ve Besin Fotograf Katalogu Olcu ve Miktarlar. Nadir Kitap; 2012.
• Pekcan G. Beslenme Durumunun Saptanmasi. Diyet El Kitabi. Ankara: Hatipoglu Yayinevi; 2013:67-142.
• Baltaci G. Obezite ve egzersiz. Saglik Bakanligi Yayinlari, Ankara; 2008.
• World Health Organization. Prevention and management of the global epidemic of obesity. Report of the WHO Consultation on Obesity. Geneva: WHO; 1997.
• Rigamonti AE, Bini S, Rocco MC, Giardini V, Massimini D, Crippa MG, Saluzzi A, Casati M, Marazzi N, Perotti M, Cimino V, Grassi G, Sartorio A, Pincelli AI. Post-prandial anorexigenic gut peptide, appetite and glucometabolic responses at different eating rates in obese patients undergoing laparoscopic sleeve gastrectomy. Endocrine. 2017 Jan;55(1):113-123. doi: 10.1007/s12020-016-0933-6. Epub 2016 Mar 29.
• Devlin MJ, Goldfein JA, Flancbaum L, Bessler M, Eisenstadt R. Surgical management of obese patients with eating disorders: a survey of current practice. Obes Surg. 2004 Oct;14(9):1252-7. doi: 10.1381/0960892042386940.
• Brown W, Dixon JB, Brien PO. Management of obesity--the role of surgery. Aust Fam Physician. 2006 Aug;35(8):584-6.
• Katsanos CS, Madura JA 2nd, Roust LR. Essential amino acid ingestion as an efficient nutritional strategy for the preservation of muscle mass following gastric bypass surgery. Nutrition. 2016 Jan;32(1):9-13. doi: 10.1016/j.nut.2015.07.005. Epub 2015 Aug 5.

Study record dates

Study Major Dates

• Study Start (Estimated): July 1, 2026
• Primary Completion (Estimated): January 1, 2027
• Study Completion (Estimated): February 1, 2027

Study Registration Dates

• First Submitted: May 20, 2026
• First Submitted That Met QC Criteria: June 2, 2026
• First Posted (Actual): June 9, 2026

Study Record Updates

• Last Update Posted (Actual): June 9, 2026
• Last Update Submitted That Met QC Criteria: June 2, 2026
• Last Verified: June 1, 2026

More Information

Terms related to this study

• Keywords: Obesity; GLP-1; Weight loss; Nutritional status; Bariatric Surgery; Eating Behavior; Body mass index; Ghrelin; Laparoscopic Sleeve Gastrectomy; Dietary intake; Appetite hormones; Peptite YY
• Additional Relevant MeSH Terms: Nutrition Disorders; Overnutrition; Body Weight; Body Weight Changes; Overweight; Pathological Conditions, Signs and Symptoms; Behavior; Nutritional and Metabolic Diseases; Signs and Symptoms; Behavior, Animal; Obesity; Weight Loss; Feeding Behavior; Health Care Quality, Access, and Evaluation; Investigative Techniques; Epidemiologic Methods; Data Collection; Health Care Evaluation Mechanisms; Quality of Health Care; Public Health; Environment and Public Health; Epidemiologic Measurements; Nutrition Assessment
• Other Study ID Numbers: BCKLY-YDB-2026

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Individual participant data will not be shared due to patient privacy and confidentiality concerns in accordance with Turkish Personal Data Protection Law (KVKK). Aggregate study results will be made available through peer-reviewed publication.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No