The Metabolic and Genetic Drivers of Body Composition Changes Following Weight Loss Surgery

NCT07178704 | Recruiting

• 1 other identifier: 24-0361
• Study Type: observational
• Target: 100
• Locations: 1 country
• Sites: 1

Brief Summary

Weight loss surgery is very good at reducing body weight but it can also cause the loss of both muscle and strength. Some patients undergoing weight loss surgery do not achieve their weight loss goals and regain the weight they lost. When this occurs, the loss of muscle and strength combined with the regain of weight can impact the individual's quality of life and ability to remain active and mobile. The purpose of this study is to understand the behavioral, biological, and genetic factors that influence the success of weight loss surgery and its impact on muscle mass. Bariatric surgery patients participating in the trial will be monitored prior to, and for a year following weight loss surgery, with data collected about their eating habits, hand grip strength, and the loss of fat, muscle, and body weight following surgery. In patients who undergo a routine endoscopy in advance of weight loss surgery a small sample of gut tissue will be collected to identify the expression (activity) of genes in their DNA.

Conditions

Bariatric Surgery Patients

Keywords

Body composition; Sarcopenia; Weight loss surgery; Muscle function; Protein metabolism

Outcome Measures

Primary Outcomes (1)

• Body composition

  Body composition will be determined in patients by whole-body bioelectrical impedance. Regional body composition will be additionally assessed in healthy volunteers and bariatric surgery patients undergoing metabolic assessment via whole-body dual-energy x-ray absorptiometry (DXA) imaging. Procedures will be performed on a single occasion in healthy volunteers and up to three times in bariatric patients undergoing metabolic assessment.

  Measured at baseline in both healthy volunteers & bariatric surgery patients undergoing metabolic assessment. The latter will undergo repeat assessment on two further occasions across a 1 year period post surgery.

Secondary Outcomes (5)

• Dietary Protein Intake

  Measured at baseline in both healthy volunteers & patients undergoing metabolic assessment. The latter will undergo repeat assessment on two further occasions across a 1 year period post surgery.

• Body weight

  Measured at baseline in both healthy volunteers & bariatric surgery patients. The latter will undergo repeat assessment on two further occasions across a 1 year period post surgery.

• Association between foregut gene expression and degree of weight reduction

  A single occasion from tissue collected during the routine pre-operative upper endoscopy. (baseline)

• Handgrip Strength

  Measured at baseline in both healthy volunteers & bariatric surgery patients. The latter will undergo repeat assessment on two further occasions across a 1 year period post surgery.

• Energy Intake

  Measured at baseline in both healthy volunteers & bariatric surgery patients undergoing metabolic assessment. The latter will undergo repeat assessment on two further occasions across a 1 year period post surgery.

Study Arms (1)

Bariatric Surgery Patients

Patients due to undergo either sleeve gastrectomy or gastric bypass surgery.

Eligibility Criteria

• Age: 18 Years - 65 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Patients will be recruited from those electing to undergo bariatric surgery at the University of Texas Medical Branch.

You may qualify if:

• Age: 18 to 65 years at time of consent
• BMI: 35-65 kg.m-2
• Scheduled to undergo bariatric surgery at UTMB
• All races and ethnic backgrounds
• Ability to speak and read English
• Subject has provided informed consent in a manner approved by the IRB and is willing and able to comply with the trial procedures.

You may not qualify if:

• Fails the medical criteria for bariatric surgery.
• Anemia (hematocrit \< 33 % or donated blood in the past 12 weeks.)
• Recent (5 years or less) history of cancer
• Systemic steroids or immunosuppressant use for 8 or more consecutive days in the past 6 months, or any use of anabolic steroids or growth hormones in the same period.
• Body mass index \< 35 or \> 65 kg.m-2.
• Acute infectious disease or chronic infection.
• Pregnancy or breast-feeding.
• Any medical condition that, in the opinion of the investigator, would place the subject at increased risk for participation.
• History of prior non-compliance that would, in the opinion of the investigator, make it difficult for the subject to comply with the study procedures or follow the investigator's instructions.
• Concurrent participation in another research study.
• Use of an investigational agent in the 30 days prior to signing informed consent.

Sponsors & Collaborators

• The University of Texas Medical Branch, Galveston: lead

Study Sites (1)

The University of Texas Medical Branch

Galveston, Texas, 77555, United States

RECRUITING

Biospecimen

Retention: SAMPLES WITH DNA

Plasma; Serum; Foregut tissue

MeSH Terms

Conditions

Sarcopenia

Condition Hierarchy (Ancestors)

Muscular Atrophy; Neuromuscular Manifestations; Neurologic Manifestations; Nervous System Diseases; Atrophy; Pathological Conditions, Anatomical; Pathological Conditions, Signs and Symptoms; Signs and Symptoms

Study Officials

• Emily J Lantz, PhD

  The University of Texas Medical Branch

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Emily J Lantz, PhD

CONTACT

409-772-0643; ejlantz@utmb.edu

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: August 22, 2025
• First Posted: September 17, 2025
• Study Start: November 4, 2025
• Primary Completion (Estimated): February 1, 2027
• Study Completion (Estimated): August 1, 2027
• Last Updated: July 10, 2026

Record last verified: 2026-07

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)