OGTT at Home Using CGM vs at the Clinic

NCT06862128 | Recruiting

• 1 other identifier: ogtt_cgm
• Study Type: interventional
• Target: 75
• Locations: 1 country
• Sites: 3

Brief Summary

This randomized, crossover study evaluates the feasibility and accuracy of a self-administered oral glucose tolerance test (OGTT) at home using continuous glucose monitoring (CGM) compared to a standard clinic-based OGTT. Participants with prediabetes will undergo both home-based and clinic-based OGTTs, with glucose levels measured via CGM and venous plasma glucose. The primary outcome is the correlation between CGM-based glucose values and standard OGTT results. Secondary outcomes include diagnostic agreement, metabolic hormone associations, and feasibility of home-based testing as a diagnostic tool for dysglycemia.

Conditions

Pre-diabetes; Diabetes

Keywords

Pre-diabetes; Diabetes; Oral glucose tolerance test; Continuous glucose monitoring; Glucose

Outcome Measures

Primary Outcomes (1)

• Diagnostic performance of home-based OGTT using continuous glucose monitoring

  Sensitivity, specificity, positive predictive value, negative predictive value, and area under the receiver operating characteristic curve (AUC) of the 2-hour CGM glucose value during home-based OGTT for classification of normoglycemia, prediabetes, and diabetes, using the 2-hour venous plasma glucose during clinic-based OGTT as the reference standard. Because CGM values are recorded every 5 minutes, the 2-hour CGM value will be defined as the first CGM measurement at or within 5 minutes after the 2-hour timepoint (120-125 minutes). All estimates will be reported with 95% confidence intervals.

  2 hours after the start of the OGTT

Secondary Outcomes (3)

• Diagnostic performance of lag-adjusted CGM during home-based OGTT

  0-20 minutes after the 2-hour timepoint of the OGTT (lag-adjusted)

• Reproducibility of home-based OGTT using CGM

  2 hours and 2 hours plus 0-20 minutes lag-adjustment after the start of the OGTT

• Agreement between CGM and venous plasma glucose during clinic OGTT

  During clinic OGTT (0-120 minutes)

Study Arms (2)

OGTT at the clinic then at home

EXPERIMENTAL

OGTT at the clinic then at home

Diagnostic Test: OGTT at home using CGM; Diagnostic Test: OGTT at the clinic

OGTT at home then at the clinic

EXPERIMENTAL

OGTT at home then at the clinic

Diagnostic Test: OGTT at home using CGM; Diagnostic Test: OGTT at the clinic

Interventions

OGTT at home using CGM DIAGNOSTIC_TEST

OGTT at home using CGM

Also known as: OGTT-home

OGTT at home then at the clinic; OGTT at the clinic then at home

OGTT at the clinic DIAGNOSTIC_TEST

OGTT at the clinic

Also known as: OGTT-clinic

OGTT at home then at the clinic; OGTT at the clinic then at home

Eligibility Criteria

• Age: 18 Years - 70 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Prediabetes indicated by ≥2 of the following values, measured at separate occasions or through different analyses during the past 2 years:
• \- Fasting venous plasma glucose ≥6.1 but ≤6.9 mmol/L
• \- Non-fasting venous plasma glucose ≥7.8 but ≤11.0 mmol/L
• \- HbA1c ≥39 but ≤47 mmol/mol
• Access to a smart phone which is compatible with the CGM application and has working Bluetooth connectivity
• Ability to read and respond to online instructions and questionnaires in Swedish.

You may not qualify if:

• T2D indicated by ≥2 of the following values, measured at different occasions or through different analyses:
• \- Fasting venous plasma glucose ≥7.0 mmol/L
• \- Non-fasting venous plasma glucose value ≥11.1 mmol/L
• \- HbA1c ≥48 mmol/mol
• Previous bariatric surgery e.g., gastric by-pass or gastric sleeve surgery
• Body mass index \<20 kg/m2
• Body weight \<43 kg
• Current pregnancy
• Need of regular use of GLP-1 receptor agonists, SGLT-2 inhibitors, acetaminophen or ascorbic acid supplements during the study period
• Fear of needle sticks
• Shift work during the study period
• Involvement in the study design, data collection, analysis, or participant recruitment.

Sponsors & Collaborators

• Region Jönköping County: collaborator
• Region Östergötland: collaborator
• Linkoeping University: lead

Study Sites (3)

Primary Health Care Center Bra Liv Rosenhälsan

Huskvarna, Jönköping County, 55185, Sweden

RECRUITING

Primary Health Care Center Cityhälsan Centrum

Norrköping, Norrköping, 60239, Sweden

RECRUITING

Primary Care Center Vårdcentralen Kärna

Linköping, Östergötland County, 58662, Sweden

RECRUITING

MeSH Terms

Conditions

Glucose Intolerance; Diabetes Mellitus

Condition Hierarchy (Ancestors)

Hyperglycemia; Glucose Metabolism Disorders; Metabolic Diseases; Nutritional and Metabolic Diseases; Endocrine System Diseases

Study Officials

• Peder af Geijerstam, MD, PhD

  Linkoeping University

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Peder af Geijerstam, MD, PhD

CONTACT

+46739597426; peder.af.geijerstam@liu.se

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: DIAGNOSTIC
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER GOV
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator

Study Record Dates

• First Submitted: March 1, 2025
• First Posted: March 6, 2025
• Study Start: June 11, 2025
• Primary Completion (Estimated): May 31, 2026
• Study Completion (Estimated): December 31, 2040
• Last Updated: March 24, 2026

Record last verified: 2026-03

Locations

SE (3)