Monitoring Techniques for Post-Bariatric Hypoglycemia

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: Stanford University

Must not be taking: Sulfonylureas, others

Disqualifiers: Insulinoma, Infection, Pregnancy, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: 1

60 Participants Needed

Trial Summary

What is the purpose of this trial?

Severe hypoglycemia (low blood sugar)after gastric bypass surgery is an increasingly recognized condition, characterized by symptoms of hypoglycemia after eating and inappropriately elevated insulin concentrations that occur at the time of hypoglycemia. Severe hypoglycemia can be dangerous and debilitating and can also impact cognitive function. At the moment no medical therapies have been developed for this disorder. Determining why some but not other patients develop this condition would allow for improved prediction, prevention, and treatment approaches. The purpose of the study is to understand the physiological changes observed in those patients who undergo gastric bypass and develop symptomatic hypoglycemia.

Will I have to stop taking my current medications?

The trial requires that you stop taking sulfonylureas or other medications that affect glucose metabolism at least 5 half-lives before participating. If you're on these medications, you will need to stop them before joining the study.

What data supports the effectiveness of this treatment for post-bariatric hypoglycemia?

Research shows that using continuous glucose monitoring (CGM) can help reduce low blood sugar episodes and improve blood sugar stability in people who have had bariatric surgery. This monitoring helps in understanding and managing blood sugar patterns, which can lead to better treatment decisions. ^{1 2 3 4 5}

Is continuous glucose monitoring safe for humans?

Continuous glucose monitoring (CGM) has been used safely in various studies to track blood sugar levels in people who have had bariatric surgery. While the studies focused on understanding glucose patterns and managing hypoglycemia, they did not report any major safety concerns related to the use of CGM devices. ^{1 2 3 5 6}

How does this treatment for post-bariatric hypoglycemia differ from other treatments?

This treatment uses continuous glucose monitoring (CGM) to track blood sugar levels and a novel system to predict and manage low blood sugar by delivering small doses of liquid glucagon. This approach is unique because it combines real-time monitoring with proactive management, unlike traditional methods that may not offer such precise control. ^{1 2 3 6 7}

Research Team

Tracey L McLaughlin, MD

Principal Investigator

Stanford University

Colleen Craig, MD

Principal Investigator

Stanford University

Eligibility Criteria

This trial is for adults aged 18-70 who've had bariatric surgery over 6 months ago and have documented low blood sugar due to high insulin. It's not for those with a tumor causing high insulin, recent acute illness, pregnant or breastfeeding women, or anyone on certain diabetes drugs.

Inclusion Criteria

I had weight loss surgery over 6 months ago.

I have a history of low blood sugar due to high insulin levels.

Exclusion Criteria

I have not had a serious infection or illness in the last 2 weeks.

I have or had an insulin-producing tumor.

Allergy to test meal or medications used in the study

Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Remote Phase

Participants wear a continuous glucose monitor (CGM) in a blinded manner for 20 days followed by an unblinded manner for another 20 days

40 days

Remote monitoring

In-Clinic Phase

Participants undergo metabolic assessments through standardized mixed meal tolerance tests and other procedures over 1-3 visits

Approximately 2 months

1-3 visits (in-person)

Follow-up

Participants are monitored for safety and effectiveness after the main trial phases

4 weeks

Treatment Details

Interventions

• Use of Cardea Solo monitoring
• Use of Continuous Glucose Monitor (CGM)

Trial Overview The study tests how 'Cardea Solo' monitoring and Continuous Glucose Monitors (CGM) can help understand why some patients develop severe hypoglycemia after gastric bypass surgery. The goal is to improve prediction and treatment of this condition.

Participant Groups

Group I: Remote Phase: Post-Bariatric Hypoglycemia Patients Experimental Treatment 2 Interventions

Participants will wear continuous glucose monitor (CGM) in a blinded manner (cannot see data output) for 20 days followed by in an unblinded manner (can see data output) for 20 days.

Group II: In-Clinic Phase: Post-Bariatric Hypoglycemia Patients with indwelling gastrostomy tube Active Control 1 Intervention

Participants will undergo standardized mixed meal tolerance tests via oral, gastrostomy tube, and concomitant oral + gastrostomy tube routes of delivery with metabolic parameters assessed.

Group III: In-Clinic Phase: Post-Bariatric Hypoglycemia Patients Active Control 1 Intervention

Participants will attend 1-3 study visits over the period of approximately 2 months, with metabolic parameters assessed under a variety of conditions. This group will also wear CGM during a portion of the metabolic tests. This may include participants from the Remote Phase or newly enrolled participants.

Group IV: In-Clinic Phase: Nonsurgical Controls Active Control 1 Intervention

Participants will attend 1-3 study visits over the period of approximately 2 months, with metabolic parameters assessed under a variety of conditions.

Group V: In-Clinic Phase: Surgical Controls Active Control 1 Intervention

Participants will attend 1-3 study visits over the period of approximately 2 months, with metabolic parameters assessed under a variety of conditions.

Who Is Running the Clinical Trial?

Stanford University

Lead Sponsor

Trials

2,527

Recruited

17,430,000+

American Diabetes Association

Collaborator

Trials

148

Recruited

102,000+

Findings from Research

Continuous glucose monitoring (CGM) significantly reduces the time patients with post-bariatric hypoglycaemia (PBH) spend in hypoglycaemia when they have access to real-time data and alarms, with a median reduction from 1.4% to 0.7% for severe hypoglycaemia (<60 mg/dL).

CGM also helps maintain better overall glucose levels, allowing patients to spend more time in the normal glucose range (70-180 mg/dL) and reducing glycaemic variability, which can enhance safety for those with hypoglycaemia unawareness.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Continuous glucose monitoring in patients with post-bariatric hypoglycaemia reduces hypoglycaemia and glycaemic variability. Cummings, C., Jiang, A., Sheehan, A., et al.[2023]

Continuous glucose monitoring (CGM) is primarily used in post-bariatric surgery patients to analyze glucose patterns and evaluate glycemic treatment outcomes, with most studies utilizing CGM for 3-7 days in a blinded mode.

The accuracy of CGM devices, such as the Freestyle Libre, was reported in only one study, showing a mean absolute relative difference of 21.7%, indicating a need for further research on the effectiveness of CGM in improving glucose control.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Use of Continuous Glucose Monitoring in Patients Following Bariatric Surgery: A Scoping Review. Yu, Y., Groth, SW.[2023]

Post-bariatric hypoglycemia (PBH) occurs in over half (54.3%) of patients after bariatric surgery, with nocturnal PBH affecting about 16.4% of patients, indicating a significant risk following these procedures.

The rates of PBH are similar for Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG), but RYGB is associated with greater glycemic variability, and the likelihood of experiencing PBH increases over time after surgery.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Rate of post-bariatric hypoglycemia using continuous glucose monitoring: A meta-analysis of literature studies. Lupoli, R., Lembo, E., Rainone, C., et al.[2022]

Continuous glucose monitoring (CGM) effectively demonstrated increased glycemic variability in individuals who underwent Roux-en-Y gastric bypass (RYGB) and showed that a low-carbohydrate diet significantly reduced this variability.

However, CGM overestimated actual blood glucose levels by about 1.1 mmol/l in the hypoglycemic range, which is important to consider when using CGM for diagnosing hypoglycemia in RYGB patients.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Continuous Glucose Monitoring After Gastric Bypass to Evaluate the Glucose Variability After a Low-Carbohydrate Diet and to Determine Hypoglycemia. Nielsen, JB., Abild, CB., Pedersen, AM., et al.[2019]

Continuous glucose monitoring (CGM) revealed that patients who underwent gastric bypass surgery often experience high glucose variability and hypoglycemia, which can significantly affect their daily activities and metabolic health.

Implementing a low glycemic index diet helped reduce glucose variability and hypoglycemic episodes in both patients, highlighting the importance of dietary management and psychological support in improving their overall health post-surgery.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Continuous glucose monitoring in the management of patients after gastric bypass Rodríguez Flores, M., Cruz Soto, RC., Vázquez Velázquez, V., et al.[2020]

A novel system using continuous glucose monitoring (CGM) and a glucagon delivery pump successfully predicted and managed hypoglycemia in seven participants with postbariatric hypoglycemia (PBH), demonstrating safety and feasibility.

After initial adjustments to the glucagon dosage and algorithm, the system effectively increased the time participants spent above the hypoglycemia threshold, indicating improved management of hypoglycemic episodes without causing severe side effects.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Design and Clinical Evaluation of a Novel Low-Glucose Prediction Algorithm with Mini-Dose Stable Glucagon Delivery in Post-Bariatric Hypoglycemia. Laguna Sanz, AJ., Mulla, CM., Fowler, KM., et al.[2019]

Continuous glucose monitoring (CGM) effectively identified hypoglycemic episodes in a patient after gastric bypass surgery, which were not detected during a 72-hour fasting period, highlighting its utility in diagnosing hypoglycemia that may be confused with dumping syndrome.

After implementing dietary changes and treatment with acarbose, no further hypoglycemic episodes occurred over an 8-month follow-up, demonstrating the potential for CGM to monitor treatment success in managing these episodes.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Usefulness of continuous glucose monitoring for the diagnosis of hypoglycemia after a gastric bypass in a patient previously treated for type 2 diabetes. Hanaire, H., Dubet, A., Chauveau, ME., et al.[2021]

References

1. England pubmed.ncbi.nlm.nih.gov

Continuous glucose monitoring in patients with post-bariatric hypoglycaemia reduces hypoglycaemia and glycaemic variability. [2023]

2. United States pubmed.ncbi.nlm.nih.gov

Use of Continuous Glucose Monitoring in Patients Following Bariatric Surgery: A Scoping Review. [2023]

3. Netherlands pubmed.ncbi.nlm.nih.gov

Rate of post-bariatric hypoglycemia using continuous glucose monitoring: A meta-analysis of literature studies. [2022]

4. United States pubmed.ncbi.nlm.nih.gov

Continuous Glucose Monitoring After Gastric Bypass to Evaluate the Glucose Variability After a Low-Carbohydrate Diet and to Determine Hypoglycemia. [2019]

5. England pubmed.ncbi.nlm.nih.gov

Continuous glucose monitoring in the management of patients after gastric bypass [2020]

6. United States pubmed.ncbi.nlm.nih.gov

Design and Clinical Evaluation of a Novel Low-Glucose Prediction Algorithm with Mini-Dose Stable Glucagon Delivery in Post-Bariatric Hypoglycemia. [2019]

7. United States pubmed.ncbi.nlm.nih.gov

Usefulness of continuous glucose monitoring for the diagnosis of hypoglycemia after a gastric bypass in a patient previously treated for type 2 diabetes. [2021]