Longitudinal Observation of Insulin Requirements and Sensor Use in Pregnancy

Completed

Conditions: Type 1 Diabetes Mellitus
Pregnancy in Diabetics

Interventions: Device: Dexcom G6 CGM

Registration Number: NCT03761615

Lead Sponsor: Sansum Diabetes Research Institute

Brief Summary: The overall goal of this study is to enroll pregnant women with type 1 diabetes and follow their glycemic outcomes prospectively throughout pregnancy and into the post-partum period. The investigators anticipate that when compared to subjects using an Artificial pancreas system (AP) as part of a future protocol, this comparator group of subjects undergoing usual care will exhibit less time in target continuous glucose monitoring (CGM) glucose range defined as 63-140 mg/dL and an increased duration of hypoglycemia with CGM glucose \<63 mg/dL.

Detailed Description: This is an observational study. Data collected will include records of continuous glucose monitoring (CGM) based glucose, insulin delivery, self-monitoring of blood glucose (SMBG), and maternal and fetal outcomes from pregnant women with type 1 diabetes. These data will be used to: (1) develop and refine algorithms for an AP system tailored to the needs of pregnant women with type 1 diabetes, (2) to serve as a comparator group for concurrent AP protocols, (3) describe Dexcom G6 CGM data throughout the pregnancy, and (4) describe insulin changes which occur in pregnancy.

Recruitment & Eligibility

Status: COMPLETED

Sex: Female

Target Recruitment: 25

Inclusion Criteria

Clinical diagnosis, based on investigator assessment, of T1D for at least one year and using insulin for at least 1 year.
Criteria for documented hyperglycemia (at least 1 must be met):
- Fasting glucose ≥126 mg/dL
- Two-hour OGTT glucose ≥200 mg/dL
- HbA1c ≥6.5% documented
- Random glucose ≥200 mg/dL with symptoms
- No data at diagnosis is available but the participant has a convincing history of hyperglycemia consistent with T1D
Criteria for requiring insulin at diagnosis (1 must be met):
- Participant required insulin at diagnosis and continually thereafter.
- Participant did not start insulin at diagnosis but upon investigator review likely needed insulin (significant hyperglycemia that did not respond to oral agents) and did require insulin eventually and used continually.
- Participant did not start insulin at diagnosis but continued to be hyperglycemic, had positive islet cell antibodies - consistent with latent autoimmune diabetes in adults (LADA) and did require insulin eventually and used continually.
Currently using an insulin pump for diabetes management
Currently using or willing to use an insulin-to-carbohydrate ratio to calculate meal bolus sizes
Willing to change insulin infusion site at least every 3 days.
Confirmed pregnancy
Current gestational age <17 weeks
Age 18-40 years
HbA1c <10.0%
Demonstration of proper mental status and cognition for the study
Ability to access the internet and upload CGM data remotely if needed
An understanding of and willingness to follow the protocol and sign the informed consent

Exclusion Criteria

670 G users in Auto mode
Current gestational age ≥17 weeks
Cystic fibrosis
A known medical condition that in the judgment of the investigator might interfere with the completion of the protocol such as the following examples:
- Inpatient psychiatric treatment in the past 6 months
- Abnormal renal function test results (calculated GFR <60 mL/min/1.73m2); testing required for subjects with diabetes duration of greater than 5 years post onset of puberty
- Active gastroparesis
- Abuse of alcohol or recreational drugs
- Infectious process not anticipated to resolve prior to study procedures (e.g. meningitis, pneumonia, osteomyelitis)
- Uncontrolled arterial hypertension (Resting diastolic blood pressure >95mmHg and/or systolic blood pressure >160 mmHg) at the time of screening
- Chronic oral steroid use
A recent injury to body or limb, muscular disorder, use of any medication, any carcinogenic disease, or other significant medical disorder if that injury, medication or disease in the judgment of the investigator will affect the completion of the protocol

Study & Design

Study Type: OBSERVATIONAL

Study Design: Not specified

Arm && Interventions

Group	Intervention	Description
type 1 diabetes and pregnancy	Dexcom G6 CGM	Pregnant women with T1D on insulin pumps (CSII/SAP/PLGS) will be offered enrollment in a prospective study that will capture: 1) Dexcom G6 CGM data, 2) self-monitoring of blood glucose (SMBG), 3) insulin pump settings, 4) insulin delivery records, and 5) maternal and fetal outcomes.

Primary Outcome Measures

Name	Time	Method
Percentage of Time in Range Glucose Levels 63-140 mg/dL as Determined by CGM	Prior to 17 weeks gestation (enrollment) through up to 6 weeks postpartum	Time in range defined as 63-140 mg/dL as determined by CGM analysis

Secondary Outcome Measures

Name	Time	Method
Percentage of Time Spent Above Target Glucose Range (> 140 mg/dL) as Determined by CGM	Prior to 17 weeks gestation (enrollment) through up to 6 weeks postpartum	Time spent above target cgm glucose range defined as \>140 mg/dL
Percentage of Percentage of Time Spent Below Target Glucose (<63 mg/dL) as Determined by CGM	Prior to 17 weeks gestation (enrollment) through up to 6 weeks postpartum	Time spent below target cgm glucose range defined as glucose \<63 mg/dL
Episodes of Clinically Significant Hyperglycemia	Prior to 17 weeks gestation (enrollment) through up to 6 weeks postpartum	Episodes of clinically significant hyperglycemia with CGM glucose \>180 mg/dL
Basal Insulin Requirements Over Last 2 Weeks of Third Trimester	2 weeks	Basal daily insulin requirements (units/kg/day) over last 2 weeks of third trimester
Carbohydrate Consumption Over Last 2 Weeks of Third Trimester	2 weeks	Carbohydrate consumption (g/(kg\*day)) over last 2 weeks of third trimester
Total Daily Insulin Requirements Over Last 2 Weeks of Third Trimester	2 weeks	Total daily insulin requirements (units/kg/day) over last 2 weeks of third trimester

Trial Locations

Locations (3): Mayo Clinic
🇺🇸
Rochester, Minnesota, United States
Icahn School of Medicine at Mount Sinai
🇺🇸
New York, New York, United States
Sansum Diabetes Research Institute
🇺🇸
Santa Barbara, California, United States