Socioecological Factors Associated With Ethnic Disparities in Bariatric Surgery Utilization and Post-WLS

NCT06342050 | Completed

• 2 other identifiers: STU-2023-0548R01MD011686
• Study Type: observational
• Target: 24
• Locations: 1 country
• Sites: 1

Brief Summary

The goal of this cross-sectional observational study is to examine potential relationships between the blood and gut microbiota of patients with obesity before and after weight loss surgery (WLS) and evaluate potential ethnic differences in the blood and gut microbiotas before and after the WLS. The main aims / objectives of this sub-study are:

• Aim 1. Compare the relationship between the blood and the gut microbiomes among a sample of (1) pre-WLS and (2) 6-month post-WLS participants. Hypothesis: Blood bacterial composition will resemble that of the gut microbiome among pre-WLS participants. Because the effect of WLS on the blood microbiome is not known, our post-WLS results will be mostly exploratory.
• Aim 2. Determine racial differences in the blood microbiome of the pre- and post-WLS groups. Hypothesis2: Ethnic differences will be detected in both the pre- and post-WLS groups.

Conditions

Obesity; Metabolic Syndrome

Keywords

Weight loss surgery; Bariatric surgery; Gut Microbiome; Blood Microbiome

Outcome Measures

Primary Outcomes (12)

• Gut Microbial Composition

  Gut microbial composition will be measured by performing whole metagenome sequencing in samples previously stored in Zymo stool collection tubes.

  Stool samples will be collected at one time point only, within a week to their in person appointment.

• Blood Microbial Composition

  Blood microbial composition will be measured by performing 16S rRNA (ribosomal ribonucleic acid) in blood samples previously stored in Zymo blood collection tubes.

  Blood samples will be collected in fasting conditions at the Baseline visit.

• Body Weight (kg)

  Body weight will be measured with a calibrated SECA scale.

  Baseline

• Body Height (meters)

  Body height will be measured with a stadiometer.

  Baseline

• Fat Mass (Kg)

  Body fat mass will be measured by using the SECA mBCA 515.

  Baseline

• Fat-free Mass (Kg)

  Fat-free mass will be measured by using the SECA mBCA 515.

  Baseline

• Body water (%)

  Body water percentage will be measured by using the SECA mBCA 515.

  Baseline

• Skeletal Muscle Mass (kg)

  Skeletal muscle mass will be measured by using the SECA mBCA 515.

  Baseline

• Fasting Glucose (mg/dL)

  Fasting glucose will be measured after a 12h fast.

  Baseline

• Fasting Insulin (mIU/L)

  Fasting insulin will be measured after a 12h fast.

  Baseline

• Lipopolysaccharides (%)

  Lipopolysaccharides will be measured after a 12h fast.

  Baseline

• Lipopolysaccharides binding protein (mIU/L)

  Lipopolysaccharides binding protein will be measured after a 12h fast.

  Baseline

Study Arms (2)

WLS non-completers

Participants who did not have WLS as part of the main study

WLS completers

Participants who had WLS as part of the main study

Eligibility Criteria

• Age: 18 Years - 60 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64)
• Sampling Method: Non-Probability Sample

Study Population

Investigators will recruit in the following manner: * Non-surgery participants from the "non-completers" group from the main study * Participants who had bariatric surgery 6 months prior to their enrollment into this sub study, will be recruited from the "early and late completers" in the main study. If additional participants are needed, particularly due to strict ethnic requirements (limited to NHW and NHB), first, invitation emails will be sent to the Weight Wellness Clinic patients, and if recruiting at the expected rate continues to be an issue, advertisements through IRB-approved flyers on social media or in the clinic setting will be posted.

You may qualify if:

• years old
• Will belong to either Non-Hispanic Whites (NHW) or Non-Hispanic Blacks (NHB) ethnic groups
• "No-WLS" participants will have a BMI \>35 kg/m2 (threshold BMI for WLS) whereas "6 months post-WLS" participants will have no BMI requirements.

You may not qualify if:

• Having taken antibiotics in the previous 6 months;
• Metformin, proton pump inhibitors, probiotics, or prebiotics in the previous month;
• Currently following a vegetarian diet;
• Pregnancy;
• Having any infection in the previous month; and
• Having a comorbid disease that might alter the blood microbiome composition (e.g., renal failure) or the intestinal permeability (e.g., IBS).

Sponsors & Collaborators

• University of Texas Southwestern Medical Center: lead
• National Institute on Minority Health and Health Disparities (NIMHD): collaborator

Study Sites (1)

UT Southwestern Medical Center

Dallas, Texas, 75390, United States

Location

Biospecimen

Retention: SAMPLES WITH DNA

2 blood sample tubes collected at the same timepoint and 1 stool sample

MeSH Terms

Conditions

Obesity; Metabolic Syndrome

Condition Hierarchy (Ancestors)

Overweight; Overnutrition; Nutrition Disorders; Nutritional and Metabolic Diseases; Body Weight; Signs and Symptoms; Pathological Conditions, Signs and Symptoms; Insulin Resistance; Hyperinsulinism; Glucose Metabolism Disorders; Metabolic Diseases

Study Officials

• Benjamin Schneider, M.D.

  University of Texas Southwestern Medical Center

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: observational
• Observational Model: OTHER
• Time Perspective: CROSS SECTIONAL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate Professor & Division Chief - Bariatric & Foregut Surgery

Study Record Dates

• First Submitted: February 22, 2024
• First Posted: April 2, 2024
• Study Start: May 14, 2024
• Primary Completion: January 31, 2025
• Study Completion: January 31, 2025
• Last Updated: May 22, 2025

Record last verified: 2025-05

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)