ogtt at home using cgm vs at the clinic

Conditions: Pre-diabetes; Diabetes

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.

this study aims to evaluate the feasibility, accuracy, and diagnostic utility of a self-administered oral glucose tolerance test (ogtt) at home using continuous glucose monitoring (cgm) compared to a standard clinic-based ogtt. study design type: randomized, crossover study participants: 75 adults with prediabetes intervention: each participant will complete both a home-based ogtt with cgm and a clinic-based ogtt with venous plasma glucose measurement. primary objective to assess the correlation between glucose values obtained from a cgm-based home ogtt and a standard venous ogtt performed in the clinic. secondary objectives evaluate diagnostic agreement between cgm-derived and venous glucose measurements. assess variability in glucose responses between the two methods. investigate associations between ogtt results and metabolic/sex hormones. determine feasibility and patient adherence to home-based testing. methods participants will be randomized into two groups: one starting with a clinic-based ogtt, the other with a home-based ogtt, followed by a crossover period. cgm will continuously monitor glucose responses, and standard venous plasma glucose measurements will serve as the reference method. clinical relevance a validated home-based ogtt using cgm could improve access to glucose tolerance testing, reduce patient burden, and enhance early detection of dysglycemia.

Eligibility criteria:
inclusion criteria: * prediabetes indicated by both of the following in the past 2 years: * - ≥1 fasting venous plasma glucose ≥6.1 but ≤6.9 mmol/l or ≥1 non-fasting venous plasma glucose ≥7.8 but ≤11.0 mmol/l * - ≥1 hba1c ≥39 but ≤47 mmol/mol * use of glp-1 receptor agonists or sglt-2 inhibitors * 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. exclusion criteria: * previous oral glucose tolerance test (ogtt) * t2d indicated by any of the following at any time: * - 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 \<25 kg/m2, indicating an increased risk of type 1-diabetes, maturity-onset diabetes of the young or latent autoimmune diabetes in adults * body weight \<43 kg, which is a contraindication to administer the full ogtt glucose solution according to swedish guidelines * current pregnancy, because gestational diabetes is a unique entity * need of regular use of acetaminophen or ascorbic acid supplements during the study period, which may interfere with cgm accuracy33 * fear of needle sticks * involvement in the study design, data collection, analysis, or participant recruitment.

Keywords: pre-diabetes diabetes oral glucose tolerance test continuous glucose monitoring glucose