Application of FreeStyle Libre 2 for Evaluating Glycemic Variability Characteristics in Patients With Extreme Glucose Metabolism Phenotypes

NCT07564518 | Not Yet Recruiting

• 1 other identifier: 2026PHB206-001
• Study Type: observational
• Target: 120
• Locations: 0 countries
• Sites: N/A

Brief Summary

This cross-sectional study aims to further subdivide diabetes mellitus into more homogeneous subgroups by focusing on extreme glucose metabolism phenotypes, including monogenic diabetes with β cell dysfunction, hyperinsulinemia caused by excessive β cell secretion, and postprandial hypoglycemia phenotypes. By utilizing continuous glucose monitoring (CGM) technology and the FreeStyle Libre 2 glucose monitoring device, this study will evaluate glycemic variability patterns in patients with extreme glucose metabolism phenotypes and perform comparative analyses using existing CGM data from healthy populations and patients with type 2 diabetes in our center's database. The study aims to address current gaps in understanding glycemic variability characteristics under extreme β cell functional states, provide novel dynamic monitoring evidence to support early identification, precise classification, and personalized management of these special metabolic states, and simultaneously screen for biomarkers to enable more accurate disease identification, thereby offering potential avenues for improving personalized treatment of diabetes mellitus.

Conditions

Monogenic Diabetes; Hyperinsulinemia

Outcome Measures

Primary Outcomes (15)

• mean blood glucose in mmol/L

  glycemic variability data

  The study is a cross-sectional study, patients wil wear a CGM for 14 days after enrollment, and will not wear it afterwards.

• glucose management indicator (GMI) in %

  glycemic variability data

  The study is a cross-sectional study, patients wil wear a CGM for 14 days after enrollment, and will not wear it afterwards.

• highest glucose values in mmol/L

  glycemic variability data

  The study is a cross-sectional study, patients wil wear a CGM for 14 days after enrollment, and will not wear it afterwards.

• lowest glucose values in mmol/L

  glycemic variability data

  The study is a cross-sectional study, patients wil wear a CGM for 14 days after enrollment, and will not wear it afterwards.

• coefficient of variation (CV)

  glycemic variability data

  The study is a cross-sectional study, patients wil wear a CGM for 14 days after enrollment, and will not wear it afterwards.

• mean amplitude of glycemic excursions (MAGE) in mmol/L

  glycemic variability data

  The study is a cross-sectional study, patients wil wear a CGM for 14 days after enrollment, and will not wear it afterwards.

• standard deviation of blood glucose (SDBG) in mmol/L

  glycemic variability data

  The study is a cross-sectional study, patients wil wear a CGM for 14 days after enrollment, and will not wear it afterwards.

• mean of daily differences (MODD) in mmol/L

  glycemic variability data

  The study is a cross-sectional study, patients wil wear a CGM for 14 days after enrollment, and will not wear it afterwards.

• average daily risk range (ADRR)

  glycemic variability data

  The study is a cross-sectional study, patients wil wear a CGM for 14 days after enrollment, and will not wear it afterwards.

• largest amplitude of glycemic excursions (LAGE) in mmol/L

  glycemic variability data

  The study is a cross-sectional study, patients wil wear a CGM for 14 days after enrollment, and will not wear it afterwards.

• high blood glucose index (HBGI)

  glycemic variability data

  The study is a cross-sectional study, patients wil wear a CGM for 14 days after enrollment, and will not wear it afterwards.

• low blood glucose index (LBGI)

  glycemic variability data

  The study is a cross-sectional study, patients wil wear a CGM for 14 days after enrollment, and will not wear it afterwards.

• time in range (TIR) in %

  glycemic variability data

  The study is a cross-sectional study, patients wil wear a CGM for 14 days after enrollment, and will not wear it afterwards.

• time above range (TAR) in %

  glycemic variability data

  The study is a cross-sectional study, patients wil wear a CGM for 14 days after enrollment, and will not wear it afterwards.

• time below range (TBR) in %

  glycemic variability data

  The study is a cross-sectional study, patients wil wear a CGM for 14 days after enrollment, and will not wear it afterwards.

Secondary Outcomes (2)

• weight in kilograms

  The study is a cross-sectional study, and the above indicators were measured only once at the initial enrollment.

• height in meters

  The study is a cross-sectional study, and the above indicators were measured only once at the initial enrollment.

Study Arms (2)

Group A : diabetes mellitus group

Group A1 (patients with β cell dysfunction monogenic diabetes): 60 cases; Group A2 (patients with type 2 diabetes mellitus): 60 cases

Group B : normal glucose tolerance group

Group B1 (normal glucose tolerance with fasting / postprandial hyperinsulinemia): 60 cases; Group B2 (normal glucose tolerance with normal insulin levels): 60 cases

Eligibility Criteria

• Age: 18 Years - 75 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

this study will use CGM to objectively and quantitatively compare glycemic variability parameters and patterns among four groups: patients with β cell dysfunction monogenic diabetes versus patients with type 2 diabetes mellitus, and patients with hyperinsulinemia versus healthy controls. This approach will reveal the effects of extreme β cell function on diurnal glycemic variability patterns and characterize distinctive dynamic glycemic profiles. 60 patients with β cell dysfunction monogenic diabetes and 60 patients with hyperinsulinemia and normal glucose tolerance who meet the inclusion criteria outlined will be recruited from the endocrinology outpatient clinic of our hospital. Groups A1 and A2, as well as Groups B1 and B2, will be matched at a 1:1 ratio by age, sex, and BMI. In addition, Groups A1 and A2 will be matched at a 1:1 ratio by HbA1c.

You may qualify if:

• Group A1:
• Age ≥ 18 years;
• Patients with β cell dysfunction monogenic diabetes confirmed by DNA sequencing or other diagnostic testing.
• Group A2:
• Age ≥ 18 years;
• Patients with confirmed type 2 diabetes mellitus;
• Derived from this center's existing continuous glucose monitoring (CGM) database.
• Group B1:
• Age ≥ 18 years;
• Normal fasting plasma glucose (≥ 3.6 and \< 6.1 mmol/L) and normal 2-hour plasma glucose during OGTT (≥ 3 and \< 7.8 mmol/L);
• Fasting insulin ≥ 25 µU/mL and/or 2-hour insulin during OGTT greater than 10 times the fasting insulin level.
• Group B2:
• Age ≥ 18 years;
• Normal glucose tolerance meeting the 2024 ADA criteria: fasting plasma glucose \< 5.6 mmol/L, 2-hour plasma glucose during OGTT \< 7.8 mmol/L;
• According to laboratory reference standards, fasting insulin ≥ 2.6 and \< 25 µU/mL, and 2-hour insulin during OGTT 5-10 times the fasting insulin level.

You may not qualify if:

• Neonates younger than 4 months of age (congenital diabetes);
• Pregnancy;
• Patients with positive pancreatic autoantibody test results;
• Patients with severe cardiovascular or cerebrovascular diseases, hepatic disease, or renal disease;
• Patients who have participated in other clinical trials.

Sponsors & Collaborators

• Peking University People's Hospital: lead

MeSH Terms

Conditions

Hyperinsulinism

Condition Hierarchy (Ancestors)

Glucose Metabolism Disorders; Metabolic Diseases; Nutritional and Metabolic Diseases

Central Study Contacts

Qian Ren, Doctorate

CONTACT

010-88324371; qianren_xuan@126.com

Study Design

• Study Type: observational
• Observational Model: CASE CONTROL
• Time Perspective: CROSS SECTIONAL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Chief Physician,Professor

Study Record Dates

• First Submitted: April 14, 2026
• First Posted: May 4, 2026
• Study Start: May 25, 2026
• Primary Completion (Estimated): December 25, 2026
• Study Completion (Estimated): January 9, 2027
• Last Updated: June 2, 2026

Record last verified: 2026-05