Self-Administered 2-Hour Oral Glucose Tolerance Test

The goal of this randomized controlled trial is to evaluate whether self-administered postpartum diabetes screening tests in patients with gestational diabetes improves screening completion rates. The primary question it aims to answer is: Does a self-administered 75-gram oral glucose tolerance test with virtual follow-up visit increase the rate of postpartum diabetes screening within 12 weeks of delivery? Does a self-administered 75-gram oral glucose tolerance test with virtual follow-up visit increase attendance at the routine 6-week postpartum visit? Is a self-administered 75-gram oral glucose tolerance test with virtual follow-up visit associated with high patient satisfaction in their healthcare experience?

Gestational diabetes affects up to 10% of pregnancies, with increasing prevalence. Due to the risk of developing overt type 2 diabetes mellitus, patients are recommended to complete postpartum diabetes screening within 4-12 weeks of delivery. Despite these recommendations, screening rates remain low. Research evaluating reasons for low screening have identified social barriers like lack of transportation or childcare, as well as health literacy barriers. The consequences of missed screening include delay in diagnosis, delay in care, and ultimately higher health burden for the patient and the healthcare system. This study seeks to evaluate a novel approach to increase uptake of recommended postpartum diabetes screening. The primary objective of this study is to determine if a self-administered postpartum diabetes screen (75-gram oral glucose tolerance test) increases screening completion rates. Our hypothesis is that the ability to perform the 75-gram oral glucose tolerance test at home will improve compliance with screening. Secondary outcomes include (1) attendance at the routine 6-week postpartum visit and (2) patient satisfaction with virtual follow up (intervention arm only). Eligible, consenting participants will be enrolled and randomized in a 1:1 ratio to the control arm (routine postpartum care with office-based diabetes screen) or intervention arm (self-administered diabetes screen). The randomization sequence will be generated by the study statistician using a block design. Investigators will remain masked to the randomization sequence. All participants will be asked to complete a brief survey containing patient characteristics and two questions about perceived risk. Additional patient and neonatal data will be abstracted from the electronic medical record. All information will be stored in a secure password protected database. Participants allocated to the intervention arm will receive the 75-gram oral glucose load and instructions prior to hospital discharge. The test should be administered approximately 4 weeks after delivery, and this date will be provided. They will be scheduled for a virtual visit approximately 4 weeks after delivery to report their results and discuss appropriate follow-up. Following this visit, participants will be asked to complete a modified version of the Telehealth Usability Questionnaire. The questionnaire contains five questions about their satisfaction with their telemedicine experience. The scoring is based on a likert scale, 1-7, with higher scores indicating higher satisfaction. Participants will be scheduled for a routine 6-week postpartum visit. Control arm participants will attend their routine 6-week postpartum visit where the postpartum diabetes glucose screen will be ordered. They can complete the test that day if they are fasting or will be responsible for arranging test completion on another day. The study will conclude 12 weeks after delivery for each participant. At that time, any patients who have not completed the recommended postpartum diabetes screening will be contacted to ensure they have not completed screening outside of our health system/electronic medical record. If they are successfully contacted, they will be reported in intent-to-treat fashion based on self-reported completion of recommended screening.

Self-administered 75-gram oral glucose tolerance test with 4-week virtual follow-up visit. Drug: GlucoCrush

Office based oral glucose tolerance test at 6 weeks postpartum, per normal protocol. Drug: GlucoCrush

Participants will be asked to self-administer the postpartum 75-gram oral glucose tolerance test. They will be provided the glucose solution and instructions. A 4 week virtual visit will be arranged where the test results will be reported to the provider and appropriate follow up arranged based on the results of their screen.

Proportion of patients who complete recommended postpartum diabetes screening within 12 weeks of delivery. The test will be considered completed if the patient has a fasting blood glucose >/=126 mg/dL (diagnostic of type 2 diabetes and does not require a post glucose load value), or both fasting and 2-hour post 75-gram glucose load blood glucose levels are documented.

Proportion of patients who have documentation of attending an in-office visit with an obstetrics provider within 12 weeks of delivery. The visit will be considered a postpartum visit if the typical components of a postpartum partum visit are addressed (i.e. physical healing, postpartum mood assessment, breastfeeding assessment). Visits with non-obstetric specialists, emergency department visits, and nursing visits are not included in this outcome measure.

Patient satisfaction will only be assessed in the intervention arm. Satisfaction with their virtual visit will be assessed by evaluating scores from a modified version of the Telehealth Usability Questionnaire. This modified version contains 5 questions about satisfaction with telemedicine. The scoring is based on a likert scale, 1-7. 1 = strongly disagree, 7 = strongly agree, with higher scores indicating higher satisfaction. Telehealth improves my access to healthcare services. Telehealth provides for my healthcare need. Telehealth is an acceptable way to receive healthcare services. I would use telehealth services again. Overall, I am satisfied with this telehealth system.

The primary outcome will also be evaluated according to GDM classification at the time of delivery (A1 vs A2) using interaction tests.

The primary outcome will also be evaluated according to treatment with insulin (yes vs no) using interaction tests.

Inclusion Criteria: Maternal age 18 years or older English or Spanish speaking Diagnosis of gestational diabetes by any of the following criteria (1) HgbA1c 5.9-6.4% at ≤ 14 6/7 weeks, (2) HgbA1c ≥ 5.9% at 15-23 6/7 weeks, (3) 50-gram oral glucose tolerance test plasma glucose value ≥ 200 mg/dL, or (4) 2 or more abnormal plasma glucose values on a 100-gram oral glucose tolerance test with the following thresholds: fasting ≥ 95 mg/dL, 1 hour ≥ 180 mg/dL, 2 hour ≥155 mg/dL, 3 hour ≥140 mg/dL. No personal history of Type 1 or Type 2 diabetes defined by self-reported or documented history, or HgbA1c >/=6.5% at ≤ 14 6/7 weeks gestation Antepartum care with Prisma Health affiliated obstetric practices Delivery at Greenville Memorial Hospital Active Epic MyChart access at time of enrollment Capable of providing informed consent Exclusion Criteria: Pre-pregnancy diagnosis of diabetes (Type 1, 2, or other form of diabetes) No glucometer or supplies for fingerstick glucose monitoring, or inability to perform fingerstick glucose monitoring Unable to provide informed consent Inability to follow up for routine postpartum care

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