Carbohydrate Intake and Closed-Loop Insulin Delivery System during Two Subsequent Pregnancies in Type 1 Diabetes

Navigating Automated Insulin Delivery for Type 1 Diabetes Management During Pregnancy

Achieving pregnancy-specific glucose targets is difficult in pregnant individuals with type 1 diabetes (T1D), and the rates of complications for mothers and their infants remain high. Currently marketed automated insulin delivery (AID) systems are hybrid closed-loop (HCL) systems in which basal insulin delivery (with or without automated correction boluses) is driven by algorithms, and users are required to initiate meal boluses. For non-pregnant people with T1D, HCL therapy has established benefits for glycemic outcomes and quality of life. While none of the currently available HCL systems were designed for pregnancy-specific glucose targets and outcomes, preliminary data suggest that the use of HCL systems may result in improved glycemia during pregnancy. There is an accumulating body of literature examining HCL systems in pregnancy, although there are still limited data regarding the impact of HCL systems on perinatal outcomes. Many individuals conceive while using clinically available HCL systems and may be hesitant to discontinue use during pregnancy, and clinicians may consider HCL therapy for pregnant individuals who are struggling to meet recommended glycemic levels during pregnancy. We therefore offer guidance on how to counsel patients on the risks and benefits of HCL therapy in pregnancy, how to identify appropriate candidates for HCL therapy in pregnancy, and how to manage commercially available HCL systems off-label throughout gestation.

Impact of AID on Glycemic Profile and Maternal/Neonatal Outcomes in Pregnancy: A Review of the Evidence From Observational Studies

The mainstay of type 1 diabetes (T1D) management in pregnancy is optimization of glucose levels in a tight range. Achieving euglycemia has been revolutionized by advances in diabetes technology, including the development of automated insulin delivery (AID) systems. A small but growing population of gravidas with T1D elects to pursue off-label use of AID systems in pregnancy, and their outcomes have been described in numerous observational cohorts. This review aims to aggregate data from all available observational studies examining glycemic, maternal, and neonatal outcomes associated with antenatal AID use. A total of 243 pregnancies managed antenatally with AID were described in 24 publications, with largely reassuring outcomes data. Time in range (TIR) with commercial AID systems was generally acceptable, with many patients reaching pregnancy target TIR > 70% by the third trimester. Time in range with open-source AID systems appeared even higher, although with the potential tradeoff of worse time below range (TBR). Clinically, there do not appear to be major differences in pregnancy outcomes between AID systems and other methods of insulin delivery, although this assumption is based largely on indirect comparisons with other population-level reports rather than direct comparisons within analytic observational cohorts. Clinical outcomes appear superior with open-source AID compared with commercial AID, although this should be interpreted with caution based on the small sample size of this subpopulation (n = 16) and potential confounding. The real-world evidence generated by these observational studies provides invaluable information for patients and providers seeking to improve outcomes for gravidas with T1D.

Automated Insulin Delivery in Pregnancies Complicated by Type 1 Diabetes

Automated insulin delivery (AID) systems adapt insulin delivery via a predictive algorithm integrated with continuous glucose monitoring and an insulin pump. Automated insulin delivery has become standard of care for glycemic management of people with type 1 diabetes (T1D) outside pregnancy, leading to improvements in time in range, with lower risk for hypoglycemia and improved treatment satisfaction. The use of AID facilitates optimal preconception care, thus more women of reproductive age are becoming pregnant while using AID. The effectiveness and safety in pregnant populations of using AID systems with algorithms for non-pregnant populations may be impacted by requirements for lower glucose targets and existence of increased insulin resistance during gestation. The CamAPS FX is the only AID system approved for use in pregnancy. A large randomized controlled trial (RCT) with this AID system demonstrated a 10.5% increase in time in pregnancy range (an additional 2.5 hours/day) compared with standard insulin therapy in pregnant women with T1D with a baseline glycated hemoglobin A1c (HbA1c) ≥48 mmol/mol (6.5%). A RCT of AID not approved for use in pregnancy (MiniMed 780G) has also demonstrated some benefits of AID compared with standard insulin therapy with improved time in pregnancy range overnight (24 minutes), less hypoglycemia, and improved treatment satisfaction. There is also increasing evidence that AID can be safely continued during delivery and postpartum, while maintaining glycemic goals with lower risk for hypoglycemia. More AID systems are needed with flexible glucose targets in the pregnancy range and possibly with algorithms that better adapt to changing insulin requirements. More evidence is needed on the impact of AID on maternal and neonatal outcomes. We review the current evidence on the use of AID in pregnancy and postpartum.

Automated insulin delivery in pregnant women with type 1 diabetes: a systematic review and meta-analysis

AIM

The outcomes of automated insulin delivery (AID) systems in pregnant women with type 1 diabetes (T1D) have not been systematically evaluated. This study aims to evaluate the efficacy and safety of AID in pregnancy.

MATERIAL AND METHODS

Literature searches were conducted until July 5, 2024, on Embase, PubMed, Cochrane Library, and ClinicalTrials.gov website. We included clinical trials and observational studies evaluating AID systems in T1D pregnant individuals. Time in the target range (TIR, 3.5-7.8 mmol/L) was the primary outcome. Secondary outcomes included time below range (TBR, < 3.5 mmol/L), time above range (TAR, > 7.8 mmol/L), and maternal and neonatal outcomes.

RESULTS

Eighteen studies (550 participants) were included. Compared with standard care, AID did not improve 24-h TIR (mean differences [MD] 3.56%, 95% CI - 0.60 to 7.72). However, the overnight TIR increased by 10.05% (95% CI 6.57 to 13.53). The association between AID and decreased TBR (MD - 0.90%, 95% CI - 1.60 to - 0.20) was found, but not with deceased TAR. Only 7 of the 17 studies achieved the goal of a 24-h TIR above 70%. Additionally, the maternal and neonatal outcomes were comparable between AID and standard care, and AID might reduce maternal weight gain (MD - 2.54 kg, 95% CI - 3.96 to - 1.11).

CONCLUSIONS

AID did not exhibit favourable TIR when compared to standard care. However, AID could increase overnight TIR and decrease TBR. Available evidence indicates that employing AID to meet the target of a 24-h TIR above 70% remains challenging.

Glucose Control During Labour and Delivery in Type 1 Diabetes - An Update on Current Evidence

PURPOSE OF REVIEW

To provide an update on diabetes management during labour and delivery in women with type 1 diabetes with focus on appropriate insulin administration, carbohydrate supply and use of diabetes technology to support safe delivery and neonatal well-being.

RECENT FINDINGS

During active labour and elective cesarean section capillary blood glucose monitoring or continuous glucose monitoring at least hourly is recommended. Infusion with isotonic (5%) glucose can be given with adjustable infusion rate to address maternal carbohydrate requirements and to prevent maternal hypoglycemia. Subcutaneous insulin administration with multiple injections or insulin pump therapy is considered at least as safe and efficient as intravenous administration to obtain tight glycemic targets. Automated insulin delivery via insulin pump can be continued during labour and delivery. Diabetes management during labour and delivery involves intensive glucose monitoring, adequate insulin administration and carbohydrate administration to support safe delivery and neonatal well-being.

Automated Insulin Delivery for Pregnant Women With Type 1 Diabetes: Where Do We Stand?

Automated insulin delivery (AID) systems mimic an artificial pancreas via a predictive algorithm integrated with continuous glucose monitoring (CGM) and an insulin pump, thereby providing AID. Outside of pregnancy, AID has led to a paradigm shift in the management of people with type 1 diabetes (T1D), leading to improvements in glycemic control with lower risk for hypoglycemia and improved quality of life. As the use of AID in clinical practice is increasing, the number of women of reproductive age becoming pregnant while using AID is also expected to increase. The requirement for lower glucose targets than outside of pregnancy and for frequent adjustments of insulin doses during pregnancy may impact the effectiveness and safety of AID when using algorithms for non-pregnant populations with T1D. Currently, the CamAPS® FX is the only AID approved for use in pregnancy. A recent randomized controlled trial (RCT) with CamAPS® FX demonstrated a 10% increase in time in range in a pregnant population with T1D and a baseline glycated hemoglobin (HbA1c) ≥ 48 mmol/mol (6.5%). Off-label use of AID not approved for pregnancy are currently also being evaluated in ongoing RCTs. More evidence is needed on the impact of AID on maternal and neonatal outcomes. We review the current evidence on the use of AID in pregnancy and provide an overview of the completed and ongoing RCTs evaluating AID in pregnancy. In addition, we discuss the advantages and challenges of the use of current AID in pregnancy and future directions for research.

An automated insulin delivery system from pregestational care to postpartum in women with type 1 diabetes. Preliminary experience with telemedicine in 6 patients

INTRODUCTION

The use of most commercially available automated insulin delivery (AID) systems is off-label in pregnancy. However, an increasing number of women with type 1 diabetes (T1D) use such devices throughout pregnancy and delivery. We analysed the data of six women with T1D from a single centre (Diabetology Outpatient Clinic of District-63/Asl Salerno, Italy) who were able to start and maintain AID therapy with the MiniMed™ 780G (Medtronic, Minneapolis, MN, USA) throughout the pregestational care period, pregnancy, delivery, and postpartum.

METHODS

We retrospectively collected data from six patients with T1D who received training and initiation on use of the MiniMed™ 780G and attended follow-up visits throughout pregnancy (these visits were virtual because of the COVID-19 pandemic). All patients maintained their devices in the closed-loop setting throughout pregnancy and during labour and delivery. We analysed data from the pregestational phase to the first 30 days postpartum.

RESULTS

All patients achieved the recommended metabolic goals before conception [median time in range (TIR) of 88% for 70-180 mg/dL; median pregnancy-specific TIR 63-140 mg/dL (ps-TIR) of 66% and maintained the ps-TIR until delivery (median ps-TIR 83%). All patients had slightly better metrics during the night than during the day, with a very low time below range of < 63 mg/dL. Optimal glycaemic values were also maintained on the day of labour and delivery (median ps-TIR 92.5%) and in the first 30 days postpartum, with no severe hypoglycaemia. The only neonatal complications were jaundice in one child and an interatrial defect in another child.

CONCLUSION

In our well-selected and trained patients, use of the MiniMed™ 780G helped to achieve and maintain ps-metrics from the pregestational period to delivery despite the fact that the algorithm is not set to achieve the ambitious glycaemic values recommended for pregnancy.

Real-world data on the Minimed 780G advanced hybrid closed-loop system use during type 1 diabetes pregnancy: One centre observational study

Aim The efficacy of hybrid closed-loop systems (HCLs) in managing glycemic control in pregnant women with type 1 diabetes remains inadequately characterized. We evaluated the use of the Medtronic Minimed 780G HCLs.

METHODS

The retrospective observational study analyzed the glycemic and perinatal outcomes of pregnant women using the HCLs, followed at our tertiary centre. Independent t-tests were employed to compare data among trimesters based on pre-pregnancy HbA1c. The associations between glycemic parameters and perinatal outcomes were explored using Spearman rho.

RESULTS

Among the 21 women (age: 33.5 ± 4.2 years, diabetes duration: 21.2 ± 7.6 years, pre-pregnancy HbA1c 7.0 ± 1.1 % (52.9 ± 11.9 mmol/mol)) time in range (pTIR, 63-140 mg/dl; 3.5-7.8 mmol/l) increased progressively throughout pregnancy (trimesters: first: 64.0 ± 9.0 %; second:71.3 ± 11.8 %; third: 75.7 ± 8.1 %). Simultaneously, mean sensor glucose decreased (trimesters: first: 130 ± 10.4 mg/dl (7.2 ± 0.6 mmol/l); second: 120.9 ± 13.4 mg/dl (6.7 ± 0.7 mmol/l); third: 117.3 ± 9.1 mg/dl (6.5 ± 0.5 mmol/l)). Although a majority of women achieved the target pTIR until the third trimester, this did not consistently prevent the delivery of a large-for-gestational-age baby. Notably, one ketoacidosis event occurred, and there were no reported instances of severe hypoglycemia.

CONCLUSION

Use of the Minimed 780G HCLs enabled the attainment of recommended pregnancy glycemic targets for most women with type 1 diabetes in a real-world setting.

Use of Advanced Hybrid Closed-Loop System during Pregnancy: Strengths and Limitations of Achieving a Tight Glycemic Control

Background: Pregnant women with type 1 diabetes mellitus (T1DM) face an elevated risk of complications for both themselves and their newborns. Experts recommend strict glycemic control. The advanced hybrid closed-loop (AHCL) system, though not officially approved for pregnant T1DM patients, is promising for optimal glycemic control. Methods: We collected CGM metrics, HbA1c levels, insulin pump settings, and doses from a 33-year-old pregnant woman with 23-year history of T1DM from the 6th week of gestation to birth. She was initially on continuous insulin pump therapy with CGM and switched to the AHCL system (MiniMedTM 780G, Medtronic, Northridge, CA, USA) between weeks 13 and 14. Results: The AHCL system improved glycemic control from weeks 14 to 26, achieving international guidelines with TIR = 72%, TAR = 24%, TBR = 4%. At week 30, TIR was 66%, TAR 31%. By altering diet and adding 'fake carbohydrates', she maintained TIR ≥ 70%, TBR ≤ 4%, TAR ≤ 26% from week 34 to birth. A healthy 4 kg, 53 cm baby boy was born at week 38. Conclusions: The use of the AHCL system holds significant promise for improving glycemic control in pregnancy. Optimal glycemic control with MiniMedTM 780G in pregnancy requires accurate carbohydrate counting, specific timing of insulin doses in relation to meal consumption and dietary choices that reduce the glycemic load of meals continue to be crucial factors in achieving optimal glycemic control during pregnancy using the MiniMedTM 780G system. Further research and clinical studies are needed to explore the full potential of these advanced systems in managing T1DM during pregnancy and optimizing maternal and neonatal outcomes.

Tandem T:Slim X2 Insulin Pump Use in Clinical Practice Among Pregnant Individuals With Type 1 Diabetes: A Retrospective Observational Cohort Study

BACKGROUND

Insulin pump use is increasing in frequency among pregnant individuals with type 1 diabetes (T1D). Automated insulin delivery (AID) technologies have not been studied extensively in pregnancy.

METHOD

We present a retrospective case series of eight individuals with T1D who used the Tandem t:slim X2 insulin pump (Tandem Diabetes Care, Inc., CA, USA) during pregnancy. Weekly continuous glucose monitor and insulin pump data were analyzed from electronic medical records and data-sharing portals. Safety, glycemic control, and pregnancy outcomes were examined with both the control IQ (CIQ) and basal IQ (BIQ) algorithms.

RESULTS

Six CIQ and two BIQ users were studied. The mean glycated hemoglobin (A1C) during pregnancy was 6.1%, and the average time in pregnancy-recommended glycemic range (TIR; 63-140mg/dL) was 67.9%. There were no instances of diabetic ketoacidosis or severe hypoglycemia. CIQ users had a higher mean sensor glucose (127.6 mg/dL) compared to BIQ participants (118.4 mg/dL). However, the average time below range (<63 mg/dL) was 6.1% in BIQ participants compared to 1.5% in CIQ participants. CIQ participants used several strategies to achieve glycemic targets, including daytime use of sleep activity. An increased basal-to-bolus insulin ratio was negatively correlated with TIR (r=-0.415).

CONCLUSIONS

Tandem t:slim X2 insulin pumps were safely used during pregnancy in eight individuals with T1D, with variable success in achieving recommended glycemic targets. Further research is needed to understand differences in CIQ and BIQ use in pregnancy. AID device manufacturers must additionally develop further methods to target lower glucose for pregnant users.

MiniMedTM 780G Advanced Hybrid Closed-Loop System Study in Pregnant Women with Type 1 Diabetes

Background: Evaluate the impact of the MiniMed™ 780G advanced hybrid closed-loop (AHCL) system on the glucose profile of pregnant women with type 1 diabetes (T1D) and maternal-neonatal complications. Methods: From April 2021 to September 2022, pregnant women with T1D treated with the AHCL system were included in an observational multicenter retrospective study. Continuous glucose monitoring parameters were analyzed monthly during pregnancy as well as maternal-neonatal complications. Results: Thirteen pregnant women, including a twin pregnancy (age: 33 ± 3 years, hemoglobin A1c [HbA1c]: 7.3% ± 0.7%, insulin doses: 0.72 ± 0.21 U/kg/day) were analyzed. At delivery, gestational age was 37 ± 2 weeks. During first 2 weeks of pregnancy, time in range (TIR, 63-140 mg/dL) was 46% (34-55) and increased to 54% (51-59) (P < 0.01), 64% (48-68) (P < 0.01), and 66% (60-70) (P < 0.001) during the first, second, and third trimester, respectively. During the night, TIR (63-140 mg/dL) was >70% throughout pregnancy. Time below the range <63 mg/dL increased from 0.5% (0-2) to 1.3% (0.7-2.2), 2% (1.2-3.5) (P < 0.05), and 1.3% (1.31-3) (P < 0.05) during the first, second, and third trimester, respectively. At delivery, insulin doses increased to 0.89 ± 0.35 IU/kg/day (P < 0.01), and HbA1c decreased to 6.4% ± 0.6% (P = 0.005). The reported carbohydrate amount increased from 167 ± 363 g/d during early pregnancy to 243 ± 106 g/d (P < 0.01) at delivery. The birthweight was 3134 ± 711 g, with 5/14 macrosomia and 2/14 neonatal hypoglycemia. Moreover, 5/13 patients had a preeclampsia and 9/13 a cesarean section, including three cases of scarred uterus. The Clinical Trial Registration number is: CE-2022-55. Conclusion: The AHCL system provided good glucose control during pregnancy and recommendation targets were reached during the nocturnal period only. The maternal and neonatal complications remained high.

Off-label use of an automated insulin delivery system in pregnant women with type 1 diabetes

Using commercially available automated insulin delivery (AID) systems for treating type 1 diabetes during pregnancy remains controversial. This retrospective study assessed six pregnant women with type 1 diabetes who underwent AID therapy. Our observations revealed that AID treatment, in most cases, did not achieve the desired glycemic targets for pregnancy.

Automated Insulin Delivery (AID) Systems: Use and Efficacy in Children and Adults with Type 1 Diabetes and Other Forms of Diabetes in Europe in Early 2023

Type 1 diabetes (T1D) patients' lifestyle and prognosis has remarkably changed over the years, especially after the introduction of insulin pumps, in particular advanced hybrid closed loop systems (AHCL). Emerging data in literature continuously confirm the improvement of glycemic control thanks to the technological evolution taking place in this disease. As stated in previous literature, T1D patients are seen to be more satisfied thanks to the use of these devices that ameliorate not only their health but their daily life routine as well. Limited findings regarding the use of new devices in different age groups and types of patients is their major limit. This review aims to highlight the main characteristics of each Automated Insulin Delivery (AID) system available for patients affected by Type 1 Diabetes Mellitus. Our main goal was to particularly focus on these systems' efficacy and use in different age groups and populations (i.e., children, pregnant women). Recent studies are emerging that demonstrate their efficacy and safety in younger patients and other forms of diabetes.