Assessing Insulin Turnover Using an In-vivo Deuterated Water Experiment.

NCT ID: NCT04332289

Last Updated: 2020-10-01

Basic Information

• Recruitment Status: COMPLETED
• Total Enrollment: 4 participants
• Study Classification: OBSERVATIONAL
• Study Start Date: 2020-07-09
• Study Completion Date: 2020-08-20

Brief Summary

The primary objective of this study is to observe the kinetics of pre-stored and de-novo synthesized insulin that is secreted into the circulation using an in-vivo heavy water (D2O) labelling experiment in patients with postprandial hyperinsulinaemic hypoglycaemia (PHH) and non-surgical non-PHH controls.

Detailed Description

Despite an increased prevalence, the underlying pathophysiology of PHH remains incompletely understood. It is generally assumed that PHH is caused by excess insulin secretion, either due to an intrinsic beta-cell abnormality (histology showing increased beta-cell mass or signs of hyperfunction) and/or increased postprandial insulinotropic signals (also known as the incretin-effect) as a consequence of the re-arranged gastrointestinal tract and accelerated nutrient transit and absorption. Either of the two explanations would imply an altered insulin turnover in these patients with higher amounts of pre-stored insulin and/or accelerated de-novo insulin synthesis in response to stimulus-depletion of the available insulin pool. A non-invasive in vivo technique to study insulin turnover has not been established yet and data related to PHH are consequently lacking.

The primary objective of this study is to observe the kinetics of pre-stored and de-novo synthesized insulin that is secreted into the circulation using an in-vivo heavy water (D2O) labelling experiment in patients with postprandial hyperinsulinaemic hypoglycaemia (PHH) and non-surgical non-PHH controls. The investigators hypothesize that the suggested methodological approach is feasible to assess insulin turnover and provides the foundation for further studies in different target groups.

Conditions

Bariatric Surgery; Hypoglycemia; Gastric Bypass

Study Design

• Observational Model Type: CASE_CONTROL
• Study Time Perspective: CROSS_SECTIONAL

Study Groups

PHH patients

Patients following Roux-en-Y gastric bypass surgery (≥1 year ago) with confirmed post-prandial hyperinsulinemic hypoglycemia

Heavy water experiment

Intervention Type: OTHER

3 times daily heavy water (deuterated-water) and mixed meal administration for one week

Healthy controls

Non-PHH, non-surgical healthy individuals

Heavy water experiment

Intervention Type: OTHER

3 times daily heavy water (deuterated-water) and mixed meal administration for one week

Interventions

Heavy water experiment

3 times daily heavy water (deuterated-water) and mixed meal administration for one week

Intervention Type: OTHER

Eligibility Criteria

Inclusion Criteria

• Aged ≥18 years
• Roux-en-Y gastric bypass ≥1 year ago
• PHH defined as postprandial plasma or sensor glucose<3.0mmol/l according to the International Hypoglycaemia Study Group and exclusion of other causes of hypoglycaemia

• Aged ≥18 years
• Absence of any condition or previous surgery known to affect gastro-intestinal integrity and food absorption

Exclusion Criteria

• Clinically relevant weight changes (≥5%) within the past 3 months
• Incapacity to give informant consent
• Historical or current diabetes based on HbA1c ≥6.5% without glucose-lowering treatment
• Haemoglobin level below 13.5 g/l
• Ongoing treatment with glucose-lowering drugs, anorectic drugs, steroids or any medications known to affect gastric motility
• Active heart, lung, liver, gastrointestinal, renal or neurological disease
• Inability to follow study procedures
• Pregnancy or breast-feeding

• Minimum Eligible Age: 18 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

Lia Bally

OTHER

Sponsor Role: lead

Responsible Party

Lia Bally

Principal Investigator

Responsibility Role: SPONSOR_INVESTIGATOR

Principal Investigators

Lia Bally, MD, PhD

Role: PRINCIPAL_INVESTIGATOR

Bern University Hospital, University of Bern

Locations

Department of Diabetes, Endocrinology, Clinical Nutrition and Metabolism, Inselspital, Bern University Hospital

Bern, , Switzerland

Countries

Switzerland

Other Identifiers

DEEP1A

Identifier Type: -

Identifier Source: org_study_id