The Predictive Role of Preoperative Pentraxin-3 (PTX3) in Metabolic and Inflammatory Outcomes After Roux-en-Y Gastric Bypass (PTX3-BYPASS)

A Single-Center Prospective Study on PTX3 as a Predictor of Insulin Resistance and Inflammatory Resolution After Bariatric Surgery

This study evaluated the prognostic value of preoperative pentraxin-3 (PTX3) levels in predicting weight loss, inflammatory resolution (CRP, IL-6), and metabolic improvements (HOMA-IR) following Roux-en-Y gastric bypass in patients with obesity.

Study Overview

• Status: Completed
• Conditions: Inflammation; Obesity; Metabolic Syndrome; Insulin Resistance; Chronic Inflammation; C-Reactive Protein; Roux en Y Gastric Bypass; Interleukin-6
• Intervention / Treatment: Other: Biomarker Stratification by PTX3

Detailed Description

This single-center longitudinal study was conducted at Istanbul University Hospital. A total of 23 patients undergoing primary Roux-en-Y gastric bypass were included. PTX3 levels were measured preoperatively, and patients were stratified according to a data-derived cut-off (~21.7 ng/mL). Outcomes assessed at baseline, 3 months, and 6 months included body weight, BMI, excess weight loss (%EWL), fasting insulin, HOMA-IR, CRP, and IL-6. The primary hypothesis was that preoperative PTX3 would predict postoperative CRP normalization and insulin resistance improvement.

• Study Type: Observational
• Enrollment (Actual): 23

Participation Criteria

Eligibility Criteria

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

• Sampling Method: Non-Probability Sample

Study Population

Adults with obesity scheduled to undergo primary Roux-en-Y gastric bypass at Istanbul University Hospital.

Sexes Eligible for Study: All Gender-Based: No Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Age: 18-65 years
• Body mass index (BMI) ≥40 kg/m², or BMI ≥35 kg/m² with obesity-related comorbidity
• Eligible for primary Roux-en-Y gastric bypass
• Able to provide written informed consent

Exclusion Criteria:

• Previous bariatric surgery
• Severe hepatic, renal, or cardiac failure
• Active infection or inflammatory disease
• Malignancy

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Group 1: High PTX3 (≥21.7 ng/mL); Participants with preoperative serum PTX3 levels ≥21.7 ng/mL. All patients underwent Roux-en-Y gastric bypass and were followed prospectively for 6 months with metabolic and inflammatory assessments.	Other: Biomarker Stratification by PTX3; Participants were stratified into groups according to preoperative serum PTX3 levels (≥21.7 ng/mL vs. <21.7 ng/mL). All participants underwent Roux-en-Y gastric bypass and were prospectively evaluated for metabolic (HOMA-IR, %EWL) and inflammatory (CRP, IL-6) outcomes during 6 months of follow-up.; Other Names: Pentraxin-3 (PTX3) Grouping
Group 2: Low PTX3 (<21.7 ng/mL); Participants with preoperative serum PTX3 levels <21.7 ng/mL. All patients underwent Roux-en-Y gastric bypass and were followed prospectively for 6 months with metabolic and inflammatory assessments.	Other: Biomarker Stratification by PTX3; Participants were stratified into groups according to preoperative serum PTX3 levels (≥21.7 ng/mL vs. <21.7 ng/mL). All participants underwent Roux-en-Y gastric bypass and were prospectively evaluated for metabolic (HOMA-IR, %EWL) and inflammatory (CRP, IL-6) outcomes during 6 months of follow-up.; Other Names: Pentraxin-3 (PTX3) Grouping

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in HOMA-IR from baseline to 6 months	Assessment of the improvement in insulin resistance after Roux-en-Y gastric bypass, measured by the homeostasis model assessment of insulin resistance (HOMA-IR). Preoperative PTX3 stratification will be used to evaluate predictive value.	Baseline, 3 months, 6 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Percent Excess Weight Loss (%EWL) at 6 months	Evaluation of weight loss outcomes after surgery, calculated as percent excess weight loss (%EWL). Comparisons will be made between PTX3 high vs. low groups.	6 months
CRP normalization at 6 months	Proportion of patients achieving CRP ≤5 mg/L after surgery. Predictive value of baseline PTX3 will be assessed.	6 months
Change in IL-6 from baseline to 6 months	Change in serum IL-6 levels after surgery, analyzed between PTX3 high vs. low groups.	Baseline, 3 months, 6 months

Collaborators and Investigators

• Sponsor: Istanbul University

Study record dates

Study Major Dates

• Study Start (Actual): January 1, 2015
• Primary Completion (Actual): July 1, 2015
• Study Completion (Actual): September 1, 2025

Study Registration Dates

• First Submitted: September 3, 2025
• First Submitted That Met QC Criteria: November 20, 2025
• First Posted (Actual): November 21, 2025

Study Record Updates

• Last Update Posted (Actual): November 21, 2025
• Last Update Submitted That Met QC Criteria: November 20, 2025
• Last Verified: November 1, 2025

More Information

Terms related to this study

• Keywords: Insulin Resistance; Bariatric Surgery; HOMA-IR; Predictive Biomarker; Roux-en-Y Gastric Bypass; Inflammatory Biomarkers; C-Reactive Protein (CRP); Pentraxin-3 (PTX3); Metabolic Outcomes
• Additional Relevant MeSH Terms: Pathologic Processes; Nutrition Disorders; Metabolic Diseases; Overnutrition; Body Weight; Glucose Metabolism Disorders; Hyperinsulinism; Overweight; Pathological Conditions, Signs and Symptoms; Nutritional and Metabolic Diseases; Signs and Symptoms; Obesity; Metabolic Syndrome; Inflammation; Insulin Resistance; PTX3 protein
• Other Study ID Numbers: ITF_2025_09

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: The study team does not plan to share individual participant data at this time.

Drug and device information, study documents

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