CGM (Continuous Glucose Monitoring) Use in Diagnosis of Spontaneous and Reactive Hypoglycaemia

Continuous Glucose Monitoring: An Evaluation of Impact on Improving the Efficiency of Diagnostic Processes and Enhancing Patient Safety in the Management of Reactive and Spontaneous Hypoglycaemia

Use of CGM to determine diagnosis in possible spontaneous or reactive hypoglycaemia.

Use of CGM to aid treatment optimisation in spontaneous or reactive hypoglycaemia

Study Overview

• Status: Terminated
• Conditions: Insulin Resistance; Insulinoma; Hypoglycemia Unawareness; Hypoglycemia Non-Diabetic; Insulin Hypoglycemia; Hypoglycemia, Reactive; Hypoglycaemia Night; Insulinoma; Malignant, Pancreas; Spontaneous Hypoglycemia; Neuro Endocrine Tumours
• Intervention / Treatment: Device: use of continuous glucose monitoring

Detailed Description

The human body's blood sugar levels are tightly controlled by the hormone insulin, produced by the pancreas. If the pancreas produces too much insulin, then the blood sugar will fall to low levels (hypoglycaemia). Insulin overproduction can happen as a result of the body misreading a change in blood sugar levels after eating (such as after obesity surgery) or through tumours of the pancreas which overproduce insulin (insulinomas).

Hypoglycaemia can cause subtle symptoms such as tiredness, poor concentration, or dizziness and if untreated more severe symptoms including fits, coma and death. Low blood sugars can go unnoticed at night and if levels fall frequently, people can lose their ability to notice subtle symptoms.

People suspected of having hypoglycaemia require a series of investigations to try and reproduce a low blood sugar under controlled conditions. This often requires an admission to hospital for a few days and multiple finger pricks to test the blood sugar - which patients often find painful. If low blood sugars caused by too much insulin are confirmed then medical treatment is started in the first instance, with surgery possibly following later. The only way to check whether these medications are working is by home fingerprick glucose measurements. If people have low sugars at night or have lost their ability to notice symptoms of low blood sugar, it is very difficult to be sure that the medical treatment is working.

The investigators plan to use continuous glucose monitoring probes to measure patient's blood sugar prior to and during admission for formal investigation for hypoglycaemia (alongside conventional fingerprick and blood testing). This might allow us to exclude hypoglycaemia as a cause of their symptoms, avoiding lengthy admissions.

The investigators will also use this technology (alongside fingerprick testing) to test how well medical treatment is working in patients with proven hypoglycaemia.

• Study Type: Interventional
• Enrollment (Actual): 7
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Scott Akker, MBBS; Phone Number: 0207 377 7000; Email: bhnt.endocrine@nhs.net
• Study Contact Backup: Name: Craig Stiles, MBBS; Phone Number: 57133 0207 377 7000; Email: bhnt.endocrine@nhs.net

Study Locations

• United Kingdom
  • London, United Kingdom, EC1A 7BE
    • St Bartholomew's Hospital, dept of endocrinology

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 16 years to 88 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• phase 1 - under investigation for possible/probable hypoglycaemia
• phase 2 - on medical therapy for established hypoglycaemia
• Must be Able and willing to give informed consent. No vulnerable adults will be included.
• Must be Aged >18 years

Can be;

• Any ethnicity
• Any socio economic group
• Either conventional gender, or non-binary.

Exclusion Criteria:

• Must not be unwilling or unable to give consent
• Must not be unable to speak sufficient English to give consent and understand study requirements
• Must not be Aged<18 or >90 years
• Must not be lack capacity to consent
• Must not have an underlying hepatic condition
• Must not have a current excessive alcohol consumption (men regularly consuming >50 units/week, women >35 units/week)
• Must not have Diabetes Mellitus
• Must not be currently using Diabetic medication or insulin
• Must not be currently pregnant
• Must not be on haemo or peritoneal dialysis

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Diagnostic
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: patients; patients undergoing CGM monitoring	Device: use of continuous glucose monitoring; Patients will wear a CGM device whilst undergoing diagnostic testing for reactive/spontaneous hypoglycaemia and then optimisation of anti-hypoglycaemic medication.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
study arm 1 - diagnosing hypoglycaemic episodes using Continuous Glucose Monitoring of interstitial fluid as a proxy marker of blood glucose	outpatient - CGM findings reflect patient's fingerprick glucose readings; Episodes of true hypoglycaemia (glucose measurement <4, <3.0, <2.2mmol/L as decided by finger prick glucose testing) are captured by the CGM device	up to 5 days prior to admission for hypoglycaemia investigations
study arm 1 - diagnosing hypoglycaemic episodes (glucose measurement <4mmol/L) using Continuous Glucose Monitoring of interstitial fluid as a proxy marker of blood glucose	inpatient - CGM findings reflect patient's fingerprick glucose readings; Episodes of true hypoglycaemia (glucose measurement <4, <3.0, <2.2mmol/L, as decided by finger prick glucose testing) are captured by the CGM device Inpatient - 72 hour fast - CGM device calls hypoglycaemia (glucose measurement <4, <3.0, <2.2mmol/L) when fingerprick/lab glucoses also do	up to 5 days in hospital during investigations for hypoglycaemia
study arm 2 - using Continuous Glucose Monitoring of interstitial fluid as a proxy marker of blood glucose to optimise hypoglycaemia treatment in patients with an established diagnosis of spontaneous or reactive hypoglycaemia	blinded phase - CGM findings reflect patient's fingerprick glucose readings- any episodes of true hypoglycaemia (as decided by fingerprick glucose testing) are captured by CGM device unblinded phase - CGM recordings help with titration of anti hypoglycaemic medications and this reduces overall incidence of hypoglycaemic episodes or duration of time spent in hypoglycaemic range (<4, <3.0, <2.2 mmol/L)	up to 30 days

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
assessing concordance between CGMS and lab/finger prick glucose testing	To determine whether CGM systems accurately record hypoglycaemia and can be used in this context	up to 10 days (study arm 1) or up to 30 days (study arm 2)

Collaborators and Investigators

• Sponsor: Barts & The London NHS Trust

Study record dates

Study Major Dates

• Study Start (Actual): December 1, 2019
• Primary Completion (Actual): March 1, 2020
• Study Completion (Actual): January 31, 2023

Study Registration Dates

• First Submitted: November 18, 2019
• First Submitted That Met QC Criteria: June 29, 2020
• First Posted (Actual): June 30, 2020

Study Record Updates

• Last Update Posted (Actual): December 12, 2023
• Last Update Submitted That Met QC Criteria: December 11, 2023
• Last Verified: December 1, 2023

More Information

Terms related to this study

• Keywords: hypoglycaemia; insulinoma
• Additional Relevant MeSH Terms: Digestive System Diseases; Glucose Metabolism Disorders; Metabolic Diseases; Neoplasms by Histologic Type; Neoplasms; Neoplasms by Site; Neoplasms, Glandular and Epithelial; Endocrine System Diseases; Digestive System Neoplasms; Neuroectodermal Tumors; Neoplasms, Germ Cell and Embryonal; Neoplasms, Nerve Tissue; Hyperinsulinism; Pancreatic Diseases; Adenoma; Pancreatic Neoplasms; Adenoma, Islet Cell; Hypoglycemia; Insulin Resistance; Neuroendocrine Tumors; Endocrine Gland Neoplasms; Insulinoma
• Other Study ID Numbers: 265405

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No