Feasibility, Acceptability, and Validity of Home Continuous Glucose Monitoring-Based Oral Glucose Tolerance Test in Youth

Adriana Rodriguez Gonzalez; Caleb Harrison; Brianna Hewitt; Jennifer L Mejier; Mary Ellen Vajravelu

doi:10.1210/clinem/dgae845

Feasibility, Acceptability, and Validity of Home Continuous Glucose Monitoring-Based Oral Glucose Tolerance Test in Youth

J Clin Endocrinol Metab. 2024 Dec 6:dgae845. doi: 10.1210/clinem/dgae845. Online ahead of print.

Authors

Adriana Rodriguez Gonzalez^{1

2}, Caleb Harrison^{1

2}, Brianna Hewitt^{1

2}, Jennifer L Mejier³, Mary Ellen Vajravelu^{1

2}

Affiliations

¹ Center for Pediatric Research in Obesity and Metabolism and Division of Pediatric Endocrinology, Diabetes, and Metabolism, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania.
² UPMC Children's Hospital of Pittsburgh, Pittsburgh, Pennsylvania.
³ Dartmouth Geisel School of Medicine, Hanover, New Hampshire.

PMID: 39657252
DOI: 10.1210/clinem/dgae845

Abstract

Context: Home-based approaches to type 2 diabetes (T2D) screening in youth may facilitate early diagnosis.

Objective: To evaluate feasibility, acceptability, and validity of a continuous glucose monitoring (CGM)-based oral glucose tolerance test (OGTT).

Design: Prospective observational study.

Setting: Pediatric Clinical and Translational Research Center.

Participants: Youth 8-18-years old with overweight/obesity and prediabetes-range hemoglobin A1c (HbA1c), fasting glucose, or 2-hour glucose on OGTT, and/or ≥1 guideline-based T2D risk factors.

Intervention: Participants completed two 75g 2-hour OGTT: 1) at research center using serum samples (research-OGTT), and 2) at home using blinded CGM (home-OGTT).

Main outcome measures: Feasibility: Percentage with valid home-OGTT data (date/time reported, transmitter returned). Acceptability: Survey and interview responses. Validity: Sensitivity, specificity, positive- and negative predictive value (PPV, NPV) of home- versus research-OGTT dysglycemia (fasting ≥100 mg/dL; 2-hour ≥140 mg/dL).

Results: Thirty-nine youth (54% female; 33% Black, 8% Hispanic/Latinx, 13% multiracial, 46% non-Hispanic White; age 14.6 ± 2.0 years; mean BMI 37.0 ± 6.7 kg/m2) participated. HbA1c was 5.7% ± 0.4%, fasting glucose 85.7 ± 8.0 mg/dL, and 2-hour glucose 115.9 ± 25.9 mg/dL. Thirty (77%) had valid home-OGTT data. Acceptability was high (92% excellent/great, 8% neutral). Due to higher average values on home-OGTT, sensitivity and NPV were high (≥80%), while specificity (fasting: 10%; 2-hour: 25%) and PPV (fasting: 3.6%, 2-hour: 18.2%) were low.

Conclusions: Home-OGTT was acceptable, but strategies to precisely capture glucose ingestion timing could improve feasibility. Alternate dysglycemia thresholds may need to be defined prior to using CGM as a method for T2D screening in youth.

Keywords: continuous glucose monitoring; obesity; oral glucose tolerance test; type 2 diabetes mellitus; youth.

© The Author(s) 2024. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com. See the journal About page for additional terms.