Multiple daily injections of insulin versus continuous subcutaneous insulin infusion for pregnant women with type 1 diabetes

Pre-existing Diabetes and Stillbirth or Perinatal Mortality: A Systematic Review and Meta-analysis

OBJECTIVE

Despite the well-recognized association between pre-existing diabetes mellitus and stillbirth or perinatal mortality, there remain knowledge gaps about the strength of association across different populations. The primary objective of this systematic review and meta-analysis was to quantify the association between pre-existing diabetes and stillbirth or perinatal mortality, and secondarily, to identify risk factors predictive of stillbirth or perinatal mortality among those with pre-existing diabetes.

DATA SOURCES

MEDLINE, EMBASE, Cochrane Database of Systematic Reviews, and Cochrane Central Register of Controlled Trials from inception to April 2022.

METHODS OF STUDY SELECTION

Cohort studies and randomized controlled trials in English or French that examined the association between pre-existing diabetes and stillbirth or perinatal mortality (as defined by the original authors) or identified risk factors for stillbirth and perinatal mortality in individuals with pre-existing diabetes were included. Data extraction was performed independently and in duplicate with the use of prespecified inclusion and exclusion criteria. Assessment for heterogeneity and risk of bias was performed. Meta-analyses were completed with a random-effects model.

TABULATION, INTEGRATION, AND RESULTS

From 7,777 citations, 91 studies met the inclusion criteria. Pre-existing diabetes was associated with higher odds of stillbirth (37 studies; pooled odds ratio [OR] 3.74, 95% CI, 3.17-4.41, I2=82.5%) and perinatal mortality (14 studies; pooled OR 3.22, 95% CI, 2.54-4.07, I2=82.7%). Individuals with type 1 diabetes had lower odds of stillbirth (pooled OR 0.81, 95% CI, 0.68-0.95, I2=0%) and perinatal mortality (pooled OR 0.73, 95% CI, 0.61-0.87, I2=0%) compared with those with type 2 diabetes. Prenatal care and prepregnancy diabetes care were significantly associated with lower odds of stillbirth (OR 0.26, 95% CI, 0.11-0.62, I2=87.0%) and perinatal mortality (OR 0.41, 95% CI, 0.29-0.59, I2=0%).

CONCLUSION

Pre-existing diabetes confers a more than threefold increased odds of both stillbirth and perinatal mortality. Maternal type 2 diabetes was associated with a higher risk of stillbirth and perinatal mortality compared with maternal type 1 diabetes.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO, CRD42022303112.

Continuous Subcutaneous Infusion Versus Multiple Daily Injections of Insulin for Pregestational Diabetes in Pregnancy: A Systematic Review and Meta-Analysis

BACKGROUND

The use of continuous subcutaneous insulin infusion (CSII) therapy in pregnancies affected by pregestational diabetes mellitus (DM) has generated mixed outcome data worthy of further investigation. This systematic review and meta-analysis aims to evaluate clinical outcomes associated with CSII versus multiple daily injections (MDIs) in pregnant persons with pregestational DM.

METHODS

A predefined, systematic, librarian-assisted search of MEDLINE (PubMed), Embase, Cochrane Library, Scopus, ClinicalTrials.gov, and World Health Organization International Clinical Trial Registry Platform (published from 2010 to 2022) yielded 3003 studies describing pregnancy outcomes associated with CSII and/or MDI for pregestational DM. The primary exposure was mode of insulin administration, with cesarean delivery and neonatal hypoglycemia as the primary maternal and neonatal outcomes, respectively. Secondary outcomes included hypertensive disorders of pregnancy, first and third-trimester glycemic control, large-for-gestational age (LGA) neonate, preterm birth, neonatal intensive care unit admission, need for respiratory support, hyperbilirubinemia, 5-minute Apgar <7, shoulder dystocia, and perinatal mortality. We calculated pooled odds ratios (OR) with 95% confidence intervals (CI) using random-effects models.

RESULTS

Among 39 eligible studies, 39% of the 5518 pregnancies included were exposed to CSII. Odds of cesarean delivery were higher with CSII (20 studies: 63% vs 56%, odds ratio [OR] 1.3 [95% confidence interval (CI) 1.2-1.5]), but we did not identify a difference in the odds of neonatal hypoglycemia (23 studies: 31% vs 34%, OR 1.1 [95% CI 0.9-1.5]). Among secondary outcomes, only the odds of LGA (20 studies: 47% vs 38%, OR 1.4 [95% CI 1.2-1.6]) were higher in individuals using CSII versus MDI.

CONCLUSIONS

Use of CSII (vs MDI) for pregestational DM in pregnancy is associated with higher odds of cesarean delivery and delivery of an LGA neonate. Further evaluation of how CSII use may influence neonatal size and delivery route is warranted.

Retrospective national cohort study of pregnancy outcomes for women with type 1 and type 2 diabetes mellitus in Republic of Ireland

AIM

Report the outcomes of pregnant women with type 1 and type 2 diabetes and to identify modifiable and non-modifiable factors associated with poor outcomes.

METHODS

Retrospective analysis of pregnancy preparedness, pregnancy care and outcomes in the Republic of Ireland from 2015 to 2020 and subsequent multivariate analysis.

RESULTS

In total 1104 pregnancies were included. Less than one third attended pre-pregnancy care (PPC), mean first trimester haemoglobin A1c was 7.2 ± 3.6% (55.5 ± 15.7 mmol/mol) and 52% received pre-conceptual folic acid. Poor preparation translated into poorer pregnancy outcomes. Livebirth rates (80%) were comparable to the background population however stillbirth rates were 8.7/1000 (four times the national rate). Congenital anomalies occurred in 42.5/1000 births (1.5 times the background rate). More than half of infants were large for gestational age and 47% were admitted to critical care. Multivariate analyses showed strong associations between non-attendance at PPC, poor glycaemic control and critical care admission (adjusted odds ratio of 1.68 (1.48-1.96) and 1.61 (1.43-1.86), p < 0.05 respectively) for women with type 1 diabetes. Smoking and teratogenic medications were also associated with critical care admission and hypertensive disorders of pregnancy.

CONCLUSION

Pregnancy outcomes in women with diabetes are suboptimal. Significant effort is needed to optimize the modifiable factors identified in this study.

Glycaemic control and novel technology management strategies in pregestational diabetes mellitus

INTRODUCTION

Pregestational diabetes (PGDM) is an increasingly common and complex condition that infers risk to both mother and infant. To prevent serious morbidity, strict glycaemic control is essential. The aim of this review is to review the glucose sensing and insulin delivering technologies currently available for women with PGDM.

METHODS

We reviewed online databases for articles relating to technology use in pregnancy using a combination of keywords and MeSH headings. Relevant articles are included below.

RESULTS

A number of technological advancements have improved care and outcomes for women with PGDM. Real time continuous glucose monitoring (rtCGM) offers clear advantages in terms of infants size and neonatal intensive care unit admissions; and further benefits are seen when combined with continuous subcutaneous insulin delivery (insulin pump) and algorithms which continuously adjust insulin levels to glucose targets (hybrid closed loop). Other advancements including flash or intermittent scanning CGM (isCGM) and stand-alone insulin pumps do not confer as many advantages for women and their infants, however they are increasingly used outside of pregnancy and many women enter pregnancy already using these devices.

DISCUSSION

This article offers a discussion of the most commonly used technologies in pregnancy and evaluates their current and future roles.

Leveraging technology for the treatment of type 1 diabetes in pregnancy: A review of past, current, and future therapeutic tools

The significant risks associated with pregnancies complicated by type 1 diabetes (T1D) were first recognized in the medical literature in the mid-twentieth century. Stringent glycemic control with hemoglobin A1c (HbA1c) values ideally less than 6% has been shown to improve maternal and fetal outcomes. The management options for pregnant women with T1D in the modern era include a variety of technologies to support self-care. Although self-monitoring of blood glucose (SMBG) and multiple daily injections (MDI) are often the recommended management options during pregnancy, many people with T1D utilize a variety of different technologies, including continuous glucose monitoring (CGM), continuous subcutaneous insulin infusion (CSII), and CSII including automated delivery or suspension algorithms. These systems have yielded invaluable diagnostic and therapeutic capabilities and have the potential to benefit this understudied higher-risk group. A recent prospective, multicenter study evaluating pregnant patients with T1D revealed that CGM significantly improves maternal glycemic parameters, is associated with fewer adverse neonatal outcomes, and minimizes burden. Outcome data for CSII, which is approved for use in pregnancy and has been utilized for several decades, remain mixed. Current evidence, although limited, for commercially available and emerging technologies for the management of T1D in pregnancy holds promise for improving patient and fetal outcomes.

Evaluation of Glycaemic Control, Glucose Variability and Hypoglycaemia on Long-Term Continuous Subcutaneous Infusion vs. Multiple Daily Injections: Observational Study in Pregnancies With Pre-Existing Type 1 Diabetes

INTRODUCTION

We evaluated the effectiveness of long-term continuous subcutaneous insulin infusion (CSII) compared with multiple daily insulin (MDI) injections for glycaemic control and variability, hypoglycaemic episodes and maternal/neonatal outcomes in pregnant women with pre-existing type 1 diabetes (pT1D).

METHODS

Our observational cohort study included 128 consecutive pregnant women with pT1D, who were treated from 1 January 2010 to 31 December 2017. Of 128 participants, 48 were on CSII and 80 were on MDI. Glycaemic control was determined by glycated haemoglobin (HbA1c) (captured in preconception and each trimester of pregnancy). Glucose variability (GV) was expressed as the coefficient of variation (CV) [calculated from self-monitoring of blood glucose (SMBG) values], and hypoglycaemia was defined as glucose values < 3.9 mmol/l. The data on maternal and neonatal outcomes were collected from obstetrical records.

RESULTS

Duration of the treatment was 8.8 ± 5.3 years in the CSII and 12.6 ± 8.0 years in the MDI group. The CSII lowered HbA1c in preconception (7.1 ± 0.1 vs. 7.9 ± 0.2%, p = 0.03) and the first (6.9 ± 0.1 vs. 7.7 ± 0.2%, p = 0.02), second (6.6 ± 0.1 vs. 7.2 ± 0.1%, p = 0.003) and third (6.5 ± 0.1 vs. 6.8 ± 0.1%, p = 0.02) trimesters significantly better than MDI. Significantly lower CV was observed only for fasting glycaemia in the first trimester (17.1 vs 28.4%, p < 0.001) in favour of CSII. Moreover, the CSII group had significantly lower mean hypoglycaemic episodes/week/patient only during the first trimester (2.0 ± 1.7 vs 4.8 ± 1.5, p < 0.01). In early pregnancy, the majority of women on CSII had less hypoglycaemia than on MDI (0-3: 79.1 vs. 29.1%; 4-6: 18.8 vs. 65.8%; ≥ 7: 2.1 vs. 5.1%, p < 0.01, respectively). We found no difference in the incidence of adverse maternal/neonatal outcomes.

CONCLUSIONS

Treatment with CSII resulted in a favourable reduction of HbA1c in the preconception period and each trimester in pregnancy. Moreover, long-term CSII treatment demonstrated more stable metabolic control with less GV of fasting glycaemia and fewer hypoglyacemic episodes only during early pregnancy.

Pregnancy outcomes among women with type 1 diabetes mellitus using continuous subcutaneous insulin infusion versus multiple daily injections: A retrospective cohort study

Background

Insulin delivery options for pregnant women with type 1 diabetes mellitus are either continuous subcutaneous insulin infusion or multiple daily injections. The aim of this paper is to compare pregnancy outcomes in women with type 1 diabetes mellitus using continuous subcutaneous insulin infusion or multiple daily injections in pregnancy.

Methods

Retrospective single-centre cohort study of 298 pregnancies booked between 2006 and 2016. Descriptive analysis was performed for HbA1c values. Logistic regression models were created to compare selected maternal and neonatal outcomes.

Results

Continuous subcutaneous insulin infusion was associated with increased risk of large-for-gestational age (aOR 2.00, 95% CI 1.20-3.34) and preterm neonates (aOR 1.80, 95% CI 1.04-3.03). Continuous subcutaneous insulin infusion had no association with increased risk of adverse pregnancy outcomes. No difference in HbA1c values existed between groups.

Conclusion

Using continuous subcutaneous insulin infusion for type 1 diabetes mellitus through pregnancy is associated with increased risk of large-for-gestational age and preterm neonates, without increased risk of associated adverse maternal or neonatal outcomes.

Diabetes Technology Update: Use of Insulin Pumps and Continuous Glucose Monitoring in the Hospital

The use of continuous subcutaneous insulin infusion (CSII) and continuous glucose monitoring (CGM) systems has gained wide acceptance in diabetes care. These devices have been demonstrated to be clinically valuable, improving glycemic control and reducing risks of hypoglycemia in ambulatory patients with type 1 diabetes and type 2 diabetes. Approximately 30-40% of patients with type 1 diabetes and an increasing number of insulin-requiring patients with type 2 diabetes are using pump and sensor technology. As the popularity of these devices increases, it becomes very likely that hospital health care providers will face the need to manage the inpatient care of patients under insulin pump therapy and CGM. The American Diabetes Association advocates allowing patients who are physically and mentally able to continue to use their pumps when hospitalized. Health care institutions must have clear policies and procedures to allow the patient to continue to receive CSII treatment to maximize safety and to comply with existing regulations related to self-management of medication. Randomized controlled trials are needed to determine whether CSII therapy and CGM systems in the hospital are associated with improved clinical outcomes compared with intermittent monitoring and conventional insulin treatment or with a favorable cost-benefit ratio.

Continuous subcutaneous insulin infusion vs multiple daily injections in pregnant women with type 1 diabetes mellitus: a systematic review and meta-analysis of randomised controlled trials and observational studies

BACKGROUND

Randomised controlled trials (RCTs) have shown an advantage of continuous subcutaneous insulin infusion (CSII) over multiple daily injections (MDI) in the general type 1 diabetes mellitus (T1DM) population. RCT data on T1DM management in pregnancy remain limited.

OBJECTIVE

We performed a systematic review of both RCTs and non-RCTs evaluating CSII vs MDI in T1DM-complicated pregnancy.

STUDY DESIGN

Electronic databases were searched for studies comparing CSII with MDI in T1DM-complicated pregnancy.

METHODS

A meta-analysis provided point estimates with 95% confidence intervals (CI). Continuous outcomes were reported as weighted mean differences (WMD) or standardised mean differences (SMD), and dichotomous data as relative risk (RR).

RESULTS

The search identified 47 studies, including 43 non-RCTs, reporting on 7824 pregnancies. The meta-analysis showed a lower HbA1c level with CSII vs MDI in the first trimester (WMD: -0.45%; 95%CI: -0.62, -0.27). This difference decreased in subsequent trimesters. Compared to MDI, therapy with CSII resulted in higher gestational weight gain (GWG) (WMD: 1.02 kg; 95%CI: 0.41, 1.62), and lower daily insulin dose requirements in the first (SMD: -0.46; 95%CI: -0.68, -0.24) and subsequent trimesters. Moreover, infants from the CSII group were more likely to be large for gestational age (LGA) (RR: 1.16; 95%CI: 1.07, 1.24) and less likely to be small for gestational age (SGA) (RR: 0.66; 95%CI: 0.45; 0.97).

CONCLUSIONS

In T1DM-complicated pregnancy, CSII compared to MDI therapy resulted in better first trimester glycaemic control; this difference decreased in subsequent trimesters. CSII therapy was associated with lower insulin requirements, higher GWG and altered risk for infants being LGA and SGA.

Emerging Technologies for the Management of Type 1 Diabetes in Pregnancy

PURPOSE OF REVIEW

The purpose of the study is to discuss emerging technologies available in the management of type 1 diabetes in pregnancy.

RECENT FINDINGS

The latest evidence suggests that continuous glucose monitoring (CGM) should be offered to all women on intensive insulin therapy in early pregnancy. Studies have additionally demonstrated the ability of CGM to help gain insight into specific glucose profiles as they relate to glycaemic targets and pregnancy outcomes. Despite new studies comparing insulin pump therapy to multiple daily injections, its effectiveness in improving glucose and pregnancy outcomes remains unclear. Sensor-integrated insulin delivery (also called artificial pancreas or closed-loop insulin delivery) in pregnancy has been demonstrated to improve time in target and performs well despite the changing insulin demands of pregnancy. Emerging technologies show promise in the management of type 1 diabetes in pregnancy; however, research must continue to keep up as technology advances. Further research is needed to clarify the role technology can play in optimising glucose control before and during pregnancy as well as to understand which women are candidates for sensor-integrated insulin delivery.

Pregnancy Outcomes and Insulin Requirements in Women with Type 1 Diabetes Treated with Continuous Subcutaneous Insulin Infusion and Multiple Daily Injections: Cohort Study

BACKGROUND

We aimed to compare glycemic control, insulin requirements, and outcomes in women with type 1 diabetes in pregnancy treated with continuous subcutaneous insulin infusion (CSII) and multiple daily injections (MDI).

METHODS

A retrospective cohort study was conducted of singleton pregnancies (>20 weeks gestation) in women with type 1 diabetes (2010-2015) at a specialist multidisciplinary maternity network in Australia. Antenatal characteristics, diabetes history and treatment details, and maternal and neonatal outcomes were compared for women with type 1 diabetes using CSII and MDI. Bolus calculator settings were reviewed for CSII. Data were obtained from individual medical records, linkage to pathology, and the Birthing Outcomes System database.

RESULTS

There were no differences in maternal characteristics or diabetes history between women managed with CSII (n = 40) and MDI (n = 127). Women treated with CSII required less insulin and less increase in total daily insulin dose/kg than MDI (40% vs. 52%). Both groups achieved similar glycemic control and no differences in pregnancy outcome. In the CSII group, carbohydrate:insulin ratios were intensified across gestation (30% breakfast, 27% lunch, 22% dinner), and insulin sensitivity factors (ISFs) changed little (7% breakfast, 0% lunch, -10% dinner).

CONCLUSIONS

There was no difference in glycemic control or pregnancy outcomes in women using CSII or MDI managed in a multidisciplinary setting. Greater adjustments are needed to ISFs with CSII therapy. Overall, these data do not support recommending CSII in pregnancy with potentially higher patient and staff demands and costs and lack of improvement in HbA1c and pregnancy outcomes.

Continuous Subcutaneous Insulin Infusion During Pregnancy in Women with Complicated Type 1 Diabetes Is Associated with Better Glycemic Control but Not with Improvement in Pregnancy Outcomes

BACKGROUND

The aim of this study was to evaluate maternal and fetal pregnancy outcomes of women with type 1 diabetes managed on continuous subcutaneous insulin infusion (CSII) compared with multiple daily insulin injections (MDI).

SUBJECTS AND METHODS

Pregnancy outcomes were assessed retrospectively in women with type 1 diabetes who were patients of the Diabetes Clinic of North Karelia Hospital (Joensuu, Finland) between 2000 and 2012. The medical records of 72 women experiencing 135 pregnancies and data of their infants were retrospectively reviewed.

RESULTS

In total, 48 pregnancies were treated with CSII and 87 with MDI. Women on CSII treatment were older and had more diabetes complications compared with women on MDI. No significant differences in glycated hemoglobin (HbA1c) levels were observed between the CSII and MDI groups before or during pregnancy. Maternal or fetal outcomes did not differ between the treatment groups. However, among women with complicated diabetes, HbA1c levels were significantly lower in the CSII group until the second trimester (prepregnancy, 7.22% vs. 8.14%, respectively [P = 0.034]; first trimester, 6.85% vs. 7.87% [P < 0.001]; second trimester, 6.41% vs. 7.03% [P = 0.029]) without an increased rate of maternal hypoglycemia.

CONCLUSIONS

Pregnancy outcomes were similar regardless of insulin treatment modality. Although using an insulin pump did not result in improvement of pregnancy outcomes, it allowed for better glycemic control in pregnancies of women with complicated diabetes. Therefore, it is worth considering in high-risk T1DM pregnancies, especially if good glycemic control is not achieved otherwise.

Comparative effectiveness of continuous subcutaneous insulin infusion using insulin analogs and multiple daily injections in pregnant women with diabetes mellitus: a systematic review and meta-analysis

We systematically reviewed the effectiveness and safety of continuous subcutaneous insulin infusion (CSII) with insulin analogs compared with multiple daily injections (MDI) in pregnant women with diabetes mellitus. We searched Medline®, Embase®, and the Cochrane Central Register of Controlled Trials through May 2013. Studies comparing CSII with MDI in pregnant women with diabetes mellitus were included. Studies using regular insulin CSII were excluded. We conducted meta-analyses where there were two or more comparable studies based on the type of insulin used in the MDI arm. Seven cohort studies of pregnant women with type 1 diabetes reported improvement in hemoglobin A1c (HbA1c) in both groups. Meta-analysis showed no difference in maternal and fetal outcomes for CSII versus MDI. Results were similar when CSII was compared with MDI with insulin analogs or regular insulin. Studies had moderate to high risk bias with incomplete descriptions of study methodology, populations, treatments, follow up, and outcomes. We conclude that observational studies reported similar improvements in HbA1c with CSII and MDI during pregnancy, but evidence was insufficient to rule out possible important differences between CSII and MDI for maternal and fetal outcomes. This highlights the need for future studies to examine the effectiveness and safety of CSII with insulin analogs and MDI in pregnant women with diabetes mellitus.

Insulin pump use in pregnancy is associated with lower HbA1c without increasing the rate of severe hypoglycaemia or diabetic ketoacidosis in women with type 1 diabetes

AIMS/HYPOTHESIS

The aim of this study was to compare glycaemic control and maternal-fetal outcomes in women with type 1 diabetes managed on insulin pumps compared with multiple daily injections of insulin (MDI).

METHODS

In a retrospective study, glycaemic control and outcomes of 387 consecutive pregnancies in women with type 1 diabetes who attended specialised clinics at three centres 2006-2010 were assessed.

RESULTS

Women using insulin pumps (129/387) were older and had a longer duration of diabetes, more retinopathy, smoked less in pregnancy, and had more preconception care (p < 0.01 for each). Among 113 pregnancies >20 weeks' gestation in women on insulin pumps and 218 in women on MDI, there was a significant difference in HbA1c in the first trimester (mean HbA1c 6.90 ± 0.71% (52 ± 7.8 mmol/mol) vs 7.60 ± 1.38% (60 ± 15.1 mmol/mol), p < 0.001), which persisted until the third trimester (mean HbA1c 6.49 ± 0.52% (47 ± 5.7 mmol/mol) vs 6.81 ± 0.85% (51 ± 9.3 mmol/mol), p = 0.002). Rates of diabetic ketoacidosis were similar in women on insulin pumps vs MDI (1.8% vs 3.0%, p = 0.72). Despite lower HbA1c, women on insulin pumps did not have an increased incidence of severe hypoglycaemia (8.0% vs 7.6%, p = 0.90) or more weight gain (16.3 ± 8.7 vs 15.2 ± 6.2 kg, p = 0.18). More large-for-gestational-age infants in the pump group (55.0% vs 39.2%, p = 0.007) may have resulted from confounding by parity.

CONCLUSIONS/INTERPRETATION

In this large multicentre study, women using insulin pumps in pregnancy had lower HbA1c without increased risk of severe hypoglycaemia or diabetic ketoacidosis but no improvement in other pregnancy outcomes. This information can help inform care providers and patients about the glycaemic effectiveness and safety of insulin pumps in pregnancy.

Insulin therapy for the treatment of type 1 diabetes during pregnancy

Pregnancies affected by type 1 diabetes (T1D) carry a major risk for poor fetal, neonatal and maternal outcomes. Achieving normoglycemia while minimizing the risk of hypoglycemia is a major goal in the management of T1D as this can greatly reduce the risk of complications. However, maintaining optimal glucose levels is challenging because insulin requirements are not uniform throughout the course of the pregnancy. Over the past decade, there has been significant improvement in the methods for glucose monitoring and insulin administration, accompanied by an increase in the number of treatment options available to pregnant patients with T1D. Through study of the scientific literature and accumulated evidence, we review advances in the management of T1D in pregnancy and offer advice on how to achieve optimal care for the patient.