Understanding glucagon and sugar metabolism after meals in people with and without PBH after weight-loss surgery

Is this trial a fit for you?

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

Researchers will compare post-prandial carbohydrate, hormone, and liver glycogen metabolism in people with PBH after Roux-en-Y gastric bypass versus those without PBH. Participants receive stable isotope tracers for glucose and glucagon and consume a measured meal, while liver glycogen is measured by MRI and a computer model is built to simulate glucagon’s role in glucose control. The study includes three visits with medical assessments, monitoring, and dietary guidance. A masked CGM will be used to track glucose patterns during the protocol.

Why it matters

Who can join: the full rules

Inclusion Criteria:

* Age 18-70 years of age, inclusive, at screening.
* Willingness to provide informed consent and follow all study procedures, including attending all scheduled visits.
* Males or females at least 2 years following Roux-en-Y gastric bypass (RYGB)
* For patients recruited to PBH group: diagnosed with ongoing PBH, with documented episodes of hypoglycemia, and history of fulfillment of Whipple's triad.

Exclusion Criteria:

* Documented hypoglycemia occurring only in the fasting state (\>12 hours fast);
* Current diabetes, defined as hemoglobin A1c \>6.5% or use of diabetes medications, except for acarbose or miglitol;
* Chronic kidney disease stage 4 or 5 (including end-stage renal disease);
* Hepatic disease, including serum ALT or AST greater than 2 times the upper limit of normal; hepatic synthetic insufficiency as defined as serum albumin \< 3.0 g/dL; or serum bilirubin \> 2.0;
* Congestive heart failure, NYHA class II, III or IV;
* History of myocardial infarction, unstable angina or revascularization within the past 6 months.
* Two or more risk factors for coronary artery disease including diabetes, uncontrolled hypertension, uncontrolled hyperlipidemia, and active tobacco use.
* History of recurrent syncope (unrelated to hypoglycemia) or active diagnosis of a cardiac arrhythmia;
* Current administration of β-blocker therapy;
* History of a cerebrovascular accident;
* Seizure disorder (other than with suspect or documented hypoglycemia);
* Active treatment with long-acting (LAR) octreotide or pasireotide;
* Active malignancy, except basal cell or squamous cell skin cancers;
* Personal or family history of pheochromocytoma or disorder with increased risk of pheochromocytoma (MEN 2, neurofibromatosis, or Von Hippel-Lindau disease);
* Known insulinoma;
* Major surgical operation within 30 days prior to screening;
* Clinically significant anemia as defined as a hematocrit \< 33%;
* Bleeding disorder, treatment with warfarin, or platelet count \<50,000;
* Blood donation (1 pint of whole blood) within the past 2 months;
* Active alcohol abuse or substance abuse;
* Current administration of oral or parenteral corticosteroids;
* Pregnancy and/ or lactation: For persons of childbearing potential: there is a requirement for a negative urine pregnancy test before any procedures.
* Not enrolled in another study that uses an investigational drug for this condition.

Where it's running

• University of Alabama
  Birmingham, Alabama, United States Recruiting
• Joslin Diabetes Center
  Boston, Massachusetts, United States Recruiting

Study contacts

• Principal investigator: Ananda Basu, MD — University of Alabama at Birmingham

Similar studies

Other studies for the same condition or treatment. Recruiting studies are listed first.

• 15-year outcomes after sleeve gastrectomy in France

  This study looks at how people who had sleeve gastrectomy have fared over 15 years to see long-term weight changes and health effects.

  Recruiting Centre Hospitalier Universitaire, Amiens · Amiens · NCT07883018

• Mother and baby health after bariatric surgery in pregnancy

  This study follows pregnant women who have had bariatric surgery and those who have not to see how nutrition, pregnancy health, and baby outcomes compare.

  Recruiting at 3 sites Helse Nord-Trøndelag HF · Ålesund, Møre og Romsdal and 2 other locations · NCT07877233

• Collagen Supplements After Sleeve Gastrectomy

  This observational study looks to see if taking collagen-containing supplements after sleeve gastrectomy affects muscle mass, body composition, and body image in adults who had bariatric surgery.

  Recruiting Mudanya University · Bursa, Yıldırım · NCT07809152

• Postoperative nausea, vomiting and pain after bariatric surgery in Sweden

  This study looks at how often people have nausea, vomiting, and pain after bariatric surgery in Sweden and whether anesthesia type or regional blocks affect those outcomes.

  Recruiting at 2 sites Umeå University · Sundsvall and 1 other locations · NCT07797374

• Hormonal changes after two bariatric surgeries in super-obese people

  This study tests whether sleeve gastrectomy with duodenojejunal bypass leads to different hormone responses and less post-meal hypoglycemia than Roux-en-Y gastric bypass in people with extreme obesity.

  Recruiting Chulalongkorn University · Pathum Wan, Bangkok · NCT07747779

• Sarcopenia After Bariatric Surgery: Changes in Muscle and Function

  This study tests how bariatric surgery affects muscle mass, strength, and physical performance over time in adults undergoing the procedure.

  Recruiting Kanuni Sultan Suleyman Training and Research Hospital · Istanbul, KÜÇÜKÇEKMECE · NCT07717333

How to take part

1. Review the eligibility criteria above with your treating physician.
2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.