CGM Use in Pregnancy & Unique Populations ELIZABETH O. BUSCHUR, MD THE OHIO STATE UNIVERSITY WEXNER MEDICAL CENTER

CGM Use in Pregnancy & Unique Populations ELIZABETH O. BUSCHUR, MD THE OHIO STATE UNIVERSITY WEXNER MEDICAL CENTER

Case 1: CGM use during pregnancy 29 yo G1P0000 at 10 5/7 weeks gestation presents to set up endocrine care. She is concerned that glucoses are higher than I would like. PMH: T1DM since age 13 complicated by hypoglycemia unawareness Obesity (wt 128 kg, BMI 45) A1c 6.2%

Questions What are our glycemic goals during pregnancy? What do you think about her history of severe hypoglycemia? How best should you treat her?

ADA/ACOG glycemic goals for pregnancy Fasting, premeal, overnight (mg/dl) Fasting 95 Premeal 100 Nocturnal 60-99 Peak postprandial (mg/dl) 1h 140 2h 120 A1c (%) 6 ADA. Preconception Care of Women with Diabetes. Diabetes Care; Vol 27, Supp 1, 2004, ADA 2017 Position Statement, Diabetes Care, Vol 40, Supp 1, 2017. Kitzmiller JL et al, Managing Preexisting Diabetes for Pregnancy: Summary of Evidence and Consensus Recommendations for Care, Diabetes Care, Vol 31, 2008, 1060-1079. ACOG Practice Bulletin No. 60 Pregestational Diabetes, Vol. 105, No. 3, 2005, 675-685.

Insulin pump settings Medtronic Minimed 530G Time 12 am 2.1 4:30 am 2.4 8 am 1.9 2 pm 2.05 9 pm 1.9 Basal rate (units/hr) Pump setting Insulin to carbohydrate ratio (ICR) Sensitivity (mg/dl) 30 Target glucose (mg/dl) 60-90 Active insulin time (hr) 4 12 am 1:8 12 pm 1:10 5 pm 1:6.5

1 st visit Are you worried about how many times a day she is testing?

How many glucoses are too many? Do you see any glycemic patterns?

Would CGM help this patient? What should you recommend?

Severe hypoglycemia Agrees to try CGM around 12-13 weeks gestation Episode of severe hypoglycemia at 15 weeks gestation Increased temporary basal rate running at time due to concern about overnight hyperglycemia (does not recall setting this)

Starting CGM & seeing red Now 16 weeks gestation

Average glucoses How many alarms is too many?

Insulin pump settings Medtronic Minimed 530G Basal rates: 12 am 2.1 units/hr 5 pm 2.05 units/hr ICR: 12 am 1:8, 12 pm 1:6 Sensitivity 50 mg/dl Target 60-120 mg/dl Active Insulin Time 4 hr

Insulin pump & CGM behaviors Bolus calculator adherence vs overriding How to manage reaching maximum bolus (25 units)? Suspending and temporary basal rates Entering factitious carbohydrates to receive more insulin Entering factitious hyperglycemia to receive more insulin Silencing or ignoring CGM alarms

Pregnancy outcome Delivered baby boy 10 lbs via cesarean section due to presumed macrosomia at 38 6/7 weeks gestation Transient neonatal hypoglycemia, resolved within 24 hours Continued to use pump & CGM during postpartum time period and breastfeeding

Case 2: CGM use in high school 16 yo young man, high school student & basketball player Transitioned from pediatric endocrinology practice T1DM since age 9 On omnipod insulin pump A1c 7.5-8.1% over past year Frustrated at erratic glucoses Trial of Dexcom G4 CGM from clinic

How to manage sports

Pump settings Omnipod pump settings Time 12 am 1.05 8 am 1.3 Basal rate (units/hr) Pump setting Insulin to carbohydrate ratio (ICR) 1:11 Sensitivity (mg/dl) 40 Target glucose 110 Active insulin time (hr) 3

Trial of Dexcom G4 in clinic Statistics Average Glucose 142 mg/dl Sensor Usage 7 of 7 Days Calibrations / day 3.1 Standard Deviation ± 72 mg/dl 50 % High 28 % Target 22 % Low Target Range 80-130 mg/dl Nighttime 10:00 PM - 6:00 AM

Questions What do you recommend for management of glucoses during basketball practice & games? What do you recommend to prevent rebound hyperglycemia?

Case 3: CGM in emerging adult 21 yo woman with T1DM since age 17 On omnipod insulin pump 5/16 Hospitalized for DKA? related to infusion site issue within first month of starting pump A1c 8-8.8% over past 12 mo

Pump settings Time 12 am 0.9 4 am 1.2 8 am 1.05 Basal rate (units/hr) Pump setting Insulin to carbohydrate ratio (ICR) Sensitivity (mg/dl) 40 Target glucose (mg/dl) 120 Active insulin time (hr) 4 12 am 1:10 11 am 1:7 5 pm 1:8

Do you notice any glycemic patterns?

What do you recommend? A) increase basal rates over 24h period B) change carb ratio at dinner C) encourage her to bolus for all carb intake D) start CGM

CGM start

CGM start leads to improvement

Week 1 What do you notice?

Week 2 What do you notice?

Overall 14 day trend

Case 4: CGM use during pregnancy 27 G1P0 teacher at 13 weeks gestation PMH: T1DM without known complications A1c 5% Celiac disease Primary hypothyroidism due to Hashimoto s thyroiditis On omnipod insulin pump and dexcom CGM

1 st visit Any patterns? She tells me she is eating snacks before bed & during night to avoid going too low. Does this change your recommendation?

Insulin pump settings Time 12 am 0.15 12 pm 0.4 6 pm 0.55 9 pm 0.3 Basal rate (units/hr) Pump setting Insulin to carbohydrate ratio (ICR) Sensitivity (mg/dl) 75 Target glucose (mg/dl) 120 Active insulin time (hr) 4 12 am 1:10 10 am 1:15

Pump download (now 21 weeks)

21 weeks gestation Any patterns?

Thank you! Any questions?