15. Management of Diabetes in Pregnancy: Standards of Care in Diabetes-2024

Recent Findings on Exercise Therapy for Blood Glucose Management in Patients with Gestational Diabetes

Inadequate management of blood glucose levels in gestational diabetes mellitus (GDM) poses risks for both pregnant women and the developing fetus. Attaining appropriate blood glucose control is crucial to mitigate potential adverse outcomes. This study aimed to consolidate the latest guidelines from representative professional societies, providing insights into exercise therapy for GDM patients and suggesting potential avenues for future research. The review was conducted with up-to-date exercise guidelines from prominent societies, such as the American College of Obstetricians and Gynecologists (ACOG), the Society of Obstetricians and Gynecologists of Canada (SOGC), the Canadian Society for Exercise Physiology (CSEP), the American College of Sports Medicine, the American Diabetes Association (ADA), and the Korean Diabetes Association. The ACOG and SOGC/CSEP recommend 150 min of low to moderate intensity exercise, 3-4 times a week, combining aerobic and resistance exercises. All guidelines advise against activities involving sudden directional changes, physical contact, a risk of falling, and exercises performed lying down. Despite cautions from the ADA and ACOG on blood glucose fluctuations during physical activity, the lack of specific methods and recommendations from other societies reveals a notable gap in evidence-based guidelines for GDM. For effective and safe blood glucose management in GDM patients, further research should be conducted on the exercise-related precautions outlined for GDM patients. Establishing ample evidence would facilitate the development of customized exercise guidelines for GDM patients.

Metformin beyond type 2 diabetes: Emerging and potential new indications

Metformin is best known as a foundational therapy for type 2 diabetes but is also used in other contexts in clinical medicine with a number of emerging and potential indications. Many of its beneficial effects may be mediated by modest effects on weight loss and insulin sensitivity, but it has multiple other known mechanisms of action. Current clinical uses beyond type 2 diabetes include: polycystic ovarian syndrome; diabetes in pregnancy/gestational diabetes; prevention of type 2 diabetes in prediabetes; and adjunct therapy in type 1 diabetes. As metformin has been in clinical use for almost 70 years, much of the underpinning evidence for its use in these conditions is, by definition, based on trials conducted before the advent of contemporary evidence-based medicine. As a result, some of the above-established uses are 'off-label' in many regulatory territories and their use varies accordingly in different countries. Going forward, several current 'repurposing' investigational uses of metformin are also being investigated: prevention of cancer (including in Li Fraumeni syndrome), renal protection, Alzheimer's disease, metabolic dysfunction-associated steatotic liver disease and promotion of healthy ageing. Despite the longevity of metformin and its important current roles beyond type 2 diabetes in clinical medicine, it has further potential and much research is ongoing.

The 2024 Flemish consensus on screening for gestational diabetes mellitus early and later in pregnancy

BACKGROUND

Screening for gestational diabetes mellitus (GDM) is important to improve pregnancy outcomes and to prevent type 2 diabetes after pregnancy. Due to a lack of evidence, the 2019 Flemish consensus did not recommend screening for GDM in early pregnancy. Recently, a large randomized controlled trial (TOBOGM) demonstrated that screening for GDM before 20 weeks reduces the risk of neonatal complications in women with risk factors when using higher cut-offs to define GDM compared to the criteria used later in pregnancy.

METHODS

Based on this new evidence, members of the Diabetes Liga, the Flemish associations of general physicians (Domus Medica), obstetricians (VVOG), midwives (VBOV), diabetes nurse educators (BVVDV), dieticians (VBVD) and clinical chemists (RBSLM) have adapted the Flemish consensus on screening for GDM.

BACKGROUND

Recommendations: As in 2019, this new consensus recommends universal screening for overt diabetes in early pregnancy preferably by measuring fasting plasma glucose by using the same diagnostic criteria as in the non-pregnant state. Based on the new evidence, women with fasting plasma glucose 95-125 mg/dL (5.3-6.9 mmol/L) before 20 weeks gestation should be diagnosed as early GDM. In addition, in women with obesity and/or a history of GDM, it is advised to perform already a 75 g oral glucose tolerance test (OGTT) between 6 and 20 weeks gestation using higher cut-offs to diagnose early GDM [fasting ≥95 mg/dL (5.3 mmol/L), 1 hour ≥ 19 mg/dL (10.6 mmol/L) and/or 2 hour ≥ 162 mg/dL (9.0 mmol/L))]. The recommendation concerning screening for GDM between 24 and 28 weeks remains unchanged with a diagnosis of GDM based on the 75 g OGTT and IADPSG criteria [fasting ≥ 92 mg/dL (5.1 mmol/L), 1 hour ≥ 180 mg/dL (10.0 mmol/L) and/or 2 hour ≥ 153 mg/dL (8.5 mmol/L)].

Fetal size monitoring in women with gestational diabetes and normal glucose tolerance

AIMS

To monitor fetal size and identify predictors for birthweight in women with gestational diabetes (GDM) and normal glucose tolerance (NGT).

METHODS

Cohort study of 1843 women universally screened for GDM, with routine ultrasounds each trimester. Women with GDM and NGT were categorized in subgroups by birthweight centile.

RESULTS

Of the total cohort, 231 (12.5%) women were diagnosed with GDM. Fetal size, incidence of large-for-gestational age (LGA: 12.3% of GDM vs. 12.9% of NGT, p = 0.822) and small-for-gestational age (SGA) neonates (4.8% of GDM vs. 5.1% of NGT, p = 0.886) were similar between GDM and NGT. GDM women with LGA neonates were more insulin resistant at baseline and had more often estimated fetal weight (EFW) ≥ P90 on the 28-33 weeks ultrasound (p = 0.033) than those with AGA (appropriate-for-gestational age) neonates. Compared to NGT women with AGA neonates, those with LGA neonates were more often obese and multiparous, had higher fasting glycemia, a worse lipid profile, and higher insulin resistance between 24 -28 weeks, with more often excessive gestational weight gain. On the 28-33 weeks ultrasound, abdominal circumference ≥ P95 had a high positive predictive value for LGA neonates in GDM (100%), whereas, in both GDM and NGT, EFW ≥ P90 and ≤ P10 had a high negative predictive value for LGA and SGA neonates (> 88%), respectively.

CONCLUSIONS

There were no differences in fetal size throughout pregnancy nor in LGA incidence between GDM and NGT women. EFW centile at 28-33 weeks correlated well with birthweight. This indicates that GDM treatment is effective and targeted ultrasound follow-up is useful. TRIAL REGISTRATION CLINICALTRIALS.GOV: NCT02036619. Registration date: January 15, 2014. https://clinicaltrials.gov/ct2/show/NCT02036619 .

Continuous Glucose Monitoring for Diabetes Management During Pregnancy: Evidence, Practical Tips, and Common Pitfalls

Continuous glucose monitoring (CGM) has the potential to revolutionize diabetes management during pregnancy by providing detailed and real-time data to patients and clinicians, overcoming many of the limitations of self-monitoring of blood glucose. Although there are limited data on the role of CGM to improve pregnancy outcomes in patients with type 2 diabetes or gestational diabetes, CGM has been shown to reduce pregnancy complications in patients with type 1 diabetes. Despite the limited data in some populations, given its ease of use and recent U.S. Food and Drug Administration approval with expanding insurance coverage, CGM has gained widespread popularity among pregnant patients with all types of diabetes. It is critical for obstetric clinicians to understand how CGM can be successfully integrated into clinical practice. We present a practical, step-wise approach to CGM data interpretation that can be incorporated into diabetes management during pregnancy and common CGM pitfalls and solutions. Although technology will continue to advance with newer-generation CGM devices and diabetes technology such as automated insulin delivery (not covered here), these key principles form a basic foundation for understanding CGM technology and its utility for pregnant people.

Point-of-Care HbA1c in Clinical Practice: Caveats and Considerations for Optimal Use

Hemoglobin A1c (A1C) is widely used for the diagnosis and management of diabetes. Accurate measurement of A1C is necessary for optimal clinical value. Assay standardization has markedly improved the accuracy and consistency of A1C testing. Devices to measure A1C at point of care (POC) are commercially available, allowing rapid results when the patient is seen. In this review, we describe how standardization of A1C testing was achieved, leading to high-quality results in clinical laboratories. We address the use of POC A1C testing in clinical situations and summarize the advantages and disadvantages of POC A1C testing. We emphasize the importance of considering the limitations of these devices and following correct testing procedures to ensure that accurate A1C results are obtained for optimal care of patients.

Continuous Glucose Monitoring Metrics for Pregnancies Complicated by Diabetes: Critical Appraisal of Current Evidence

Ascertaining the utility of continuous glucose monitoring (CGM) in pregnancy complicated by diabetes is a rapidly evolving area, as the prevalence of type 1 diabetes (T1D), type 2 diabetes (T2D), and gestational diabetes mellitus (GDM) escalates. The seminal randomized controlled trial (RCT) evaluating CGM use added to standard care in pregnancy in T1D demonstrated significant improvements in maternal glycemia and neonatal health outcomes. Current clinical guidance recommends targets for percentage time in range (TIR), time above range (TAR), and time below range (TBR) during pregnancy complicated by T1D that are widely used in clinical practice. However, the superiority of CGM over blood glucose monitoring (BGM) is still questioned in both T2D and GDM, and whether glucose targets should be different than in T1D is unknown. Questions requiring additional research include which CGM metrics are superior in predicting clinical outcomes, how should pregnancy-specific CGM targets be defined, whether CGM targets should differ according to gestational age, and if CGM metrics during pregnancy should be similar across all types of diabetes. Limiting the potential for CGM to improve pregnancy outcomes may be our inability to maintain TIR > 70% throughout gestation, a goal achieved in the minority of patients studied. Adverse pregnancy outcomes remain high in women with T1D and T2D in pregnancy despite CGM technology, and this review explores the potential reasons and questions yet to be investigated.

The use of technology in type 2 diabetes and prediabetes: a narrative review

The increasing incidence of type 2 diabetes, which represents 90% of diabetes cases globally, is a major public health concern. Improved glucose management reduces the risk of vascular complications and mortality; however, only a small proportion of the type 2 diabetes population have blood glucose levels within the recommended treatment targets. In recent years, diabetes technologies have revolutionised the care of people with type 1 diabetes, and it is becoming increasingly evident that people with type 2 diabetes can also benefit from these advances. In this review, we describe the current knowledge regarding the role of technologies for people living with type 2 diabetes and the evidence supporting their use in clinical practice. We conclude that continuous glucose monitoring systems deliver glycaemic benefits for individuals with type 2 diabetes, whether treated with insulin or non-insulin therapy; further data are required to evaluate the role of these systems in those with prediabetes (defined as impaired glucose tolerance and/or impaired fasting glucose and/or HbA1c levels between 39 mmol/mol [5.7%] and 47 mmol/mol [6.4%]). The use of insulin pumps seems to be safe and effective in people with type 2 diabetes, especially in those with an HbA1c significantly above target. Initial results from studies exploring the impact of closed-loop systems in type 2 diabetes are promising. We discuss directions for future research to fully understand the potential benefits of integrating evidence-based technology into care for people living with type 2 diabetes and prediabetes.

Insulin Management for Gestational and Type 2 Diabetes in Pregnancy

Insulin is preferred as the first-line agent for glucose management of gestational diabetes mellitus and type 2 diabetes in pregnancy when nutritional and lifestyle modifications are unable to achieve pregnancy-specific glucose targets. Individual heterogeneity in defects of insulin secretion or sensitivity in liver and muscle, unique genetic influences on pregnancy glycemic regulation, and variable cultural and lifestyle behaviors that affect meal, activity, sleep, and occupational schedules necessitate a personalized approach to insulin regimens. Newer insulin preparations have been developed to mimic the physiologic release of endogenous insulin, maintaining appropriate basal levels to cover hepatic gluconeogenesis and simulate the rapid, meal-related, bolus rise of insulin. Such physiologic basal-bolus dosing of insulin can be administered safely, achieving tighter glycemic control while reducing episodes of hypoglycemia. Insulin initiation and titration require understanding the pharmacodynamics of different insulin preparations in addition to a patient's glycemic profiles, effect of variable nutritional intake and mealtimes, physical activity, stress, timing of sleep cycles, and cultural habits. Educating and empowering patients to learn how their glucose responds to insulin, portion and content of meals, and physical activity can increase personal engagement in therapy, flexibility in eating patterns, and improved glycemic control. This Clinical Expert Series article is focused on optimizing insulin management (initiation, dosing, and titration) of gestational and type 2 diabetes in pregnancy.

Type 2 Diabetes

Type 2 diabetes (T2D) is a prevalent disease that increases risk for vascular, renal, and neurologic complications. Prevention and treatment of T2D and its complications are paramount. Many advancements in T2D care have emerged over the past 5 years, including increased understanding of the importance of early intensive glycemic control, mental health, social determinants of health, healthy eating patterns, continuous glucose monitoring, and the benefits of some drugs for preventing cardiorenal disease. This review summarizes the evidence supporting T2D prevention and treatment, focusing on aspects that are commonly in the purview of primary care physicians.

Exploring health professionals' knowledge, practices and attitudes regarding gestational diabetes: A cross-sectional Irish national survey

AIM

Gestational diabetes confers short- and long-term risk of mother and offspring health complications. Healthcare professionals such as endocrinologists, diabetes nurses, dietitians, midwives and general practitioners provide gestational diabetes care. We sought to explore healthcare professionals' perspectives on gestational diabetes care during pregnancy and postpartum.

METHODS

Healthcare professionals in the Republic of Ireland, whose role included gestational diabetes care were invited to complete an online 20-item survey between June and September 2022. Social media, professional organisations and personal networks were used for recruitment. Questions included guideline use, postpartum diabetes screening and advice practices. Analyses were performed using SPSS statistical software and free text was coded using NVivo.

RESULTS

Seventeen healthcare professions across primary and secondary care settings participated (n = 127). No differences were noted between groups (medical, nursing/midwifery, allied health/other); therefore, findings were reported as a single group. Healthcare professionals reported using multiple different guidelines to support gestational diabetes management (n = 14). The most cited were 'Health Service Executive guidelines' (24.5%), 'local guidelines' (13.2%) and National Institute for Clinical Excellence guidelines (11.3%); 12.3% cited uncertainty, and 27.5% reported not to follow any named guidelines. For postpartum follow-up, 39% felt clear guidelines were available to support practice, 37% felt appropriate systems were in place and 29% reported effective communication between primary and secondary care services. Qualitative findings emphasised a desire for improved communication between systems, participants and providers, clear interdisciplinary guidelines, and adequate resourcing for gestational diabetes management and postpartum diabetes prevention, including comprehensive support and follow-up.

CONCLUSION

System-level challenges and ineffective communication across settings are barriers to optimum postpartum care. Nationally agreed guidelines for best practice gestational diabetes management including postpartum diabetes prevention are needed.

Gestational diabetes mellitus may predispose to metabolic dysfunction-associated steatotic liver disease

The development of type 2 diabetes mellitus is a major contributing factor to the worldwide health burden of metabolic dysfunction-associated steatotic liver disease (MASLD). Insulin resistance, subclinical inflammation, dyslipidemia, obesity, and hypertension are all factors in this reciprocal interaction that contribute to the development of MASLD, which includes hepatocellular carcinoma, advanced fibrosis/cirrhosis, and non-alcoholic steatohepatitis (NASH). A new risk factor for MASLD/NASH that affects the course of the disease independently throughout life is gestational diabetes mellitus (GDM). Women with a history of GDM had a higher chance of developing NASH, according to a recent study that used a large-scale database. Although the precise etiology is yet unknown, temporary disruption of pancreatic beta cell activity during pregnancy may set off systemic inflammation, affecting distant organs including the liver. Early screening and management strategies are crucial in mitigating MASLD progression and preventing adverse cardiovascular events in affected individuals.

Continuous Glucose Monitoring for Management of Type 2 Diabetes and Perinatal Outcomes

OBJECTIVE

To evaluate the association between continuous glucose monitoring in pregnant people with type 2 diabetes and perinatal outcomes.

METHODS

This was a retrospective cohort study of pregnant people with type 2 diabetes who received prenatal care and delivered singleton, nonanomalous neonates at a single academic tertiary care center from November 1, 2019, to February 28, 2023. The primary outcome was a composite of neonatal morbidity, including hypoglycemia, hyperbilirubinemia, shoulder dystocia, large for gestational age at birth, preterm birth, neonatal intensive care unit (NICU) admission, or perinatal death. Demographics and outcomes were compared by type of monitoring (continuous glucose monitoring vs intermittent self-monitoring of blood glucose), and multivariable logistic regression estimated the association between continuous glucose monitoring use and perinatal outcomes.

RESULTS

Of 360 pregnant people who met the inclusion criteria, 82 (22.7%) used continuous glucose monitoring. The mean gestational age at continuous glucose monitoring initiation was 21.3±6.4 weeks. The use of continuous glucose monitoring was associated with lower odds of the primary composite neonatal morbidity (65.9% continuous glucose monitoring vs 77.0% self-monitoring of blood glucose, adjusted odds ratio [aOR] 0.48, 95% CI, 0.24-0.94). Continuous glucose monitoring use was also associated with lower odds of preterm birth (13.4% vs 25.2%, aOR 0.48, 95% CI, 0.25-0.93) and NICU admission (33.8% vs 47.6%, aOR 0.36, 95% CI, 0.16-0.81).

CONCLUSION

In pregnant people with type 2 diabetes, continuous glucose monitoring use was associated with less neonatal morbidity, fewer preterm births, and fewer NICU admissions.

The Associations Between Health-Related Knowledge and Health Beliefs Regarding Risk for Gestational Diabetes in American Indian and Alaska Native Female Adolescents and Young Adults at Risk for Gestational Diabetes and Their Female Caregivers: A Cross-Sectional Dyadic Analysis

INTRODUCTION

Research on associations between knowledge and health beliefs for women at risk for gestational diabetes mellitus (GDM) has focused on adults at risk for or having GDM. Gaps also exist in examining interpersonal associations with family members or peers. We examined dyadic associations between knowledge and health beliefs about the risk for GDM between and within American Indian and Alaska Native (AIAN) female adolescents and young adults (FAYAs) at risk for GDM and their mothers or adult female caregivers (FCs).

METHODS

Grounded in the Expanded Health Belief Model, we employed a cross-sectional design using baseline data from 147 dyads of AIAN FAYAs at risk for GDM and their FCs who participated in the Stopping GDM in Daughters and Mothers trial. FAYAs were 12.0 to 24.5 years of age, and 89.1% were students. FCs had a mean (SD) age of 44.0 (9.3) years, 87.0% were AIAN, 44.9% were college educated, 19.7% had ever had GDM, and 81.0% were the FAYA's mother. FAYAs and FCs completed surveys about knowledge and health beliefs (benefits, barriers, severity, susceptibility) regarding GDM risk and prevention. Bivariate correlational analyses were performed to examine associations between and within dyad members. Dyadic associations were investigated using actor-partner interdependence modeling (APIM) assuming distinguishable dyad members.

RESULTS

Compared with their FCs, FAYAs had lower health-related knowledge and perceived benefits of GDM prevention and susceptibility regarding GDM risk. APIM revealed actor and partner effects of health-related knowledge on health beliefs for dyads. In particular, positive actor effects were found for FAYAs and FCs for GDM-related knowledge with perceived benefits (P < .001), and positive partner effects of GDM-related knowledge for FCs were related to perceived susceptibility and severity for FAYAs (P < .05).

DISCUSSION

As shown in these AIAN dyads, FAYAs and their FCs, as members of one another's social network, may influence each other's health beliefs regarding GDM risk and prevention.

Diabetes Management in Detention Facilities: A Statement of the American Diabetes Association

This statement provides guidance for diabetes care in detention facilities. It focuses on areas where the processes for delivery of care to people with diabetes in detention facilities may differ from those in the community, and key points are made at the end of each section. Areas of emphasis, which inform multiple aspects discussed in this statement, include 1) timely identification or diagnosis of diabetes treatment needs and continuity of care (at reception/intake, during transfers, and upon discharge), 2) nutrition and physical activity, 3) timely access to diabetes management tools (insulin, blood glucose monitoring, tracking data, current diabetes management technologies, etc.), and 4) treatment of the whole person with diabetes (self-management education, mental health support, monitoring and addressing long-term complications, specialty care, etc.).

Glucose tolerance test with a single abnormal value as a predictor of type 2 diabetes mellitus: a multicenter retrospective study

Clinical implication of a single abnormal value (SAV) in the 100 g oral glucose tolerance test during pregnancy has not been established. We aimed to evaluate the risk of postpartum type 2 diabetes mellitus (T2DM) and investigate adverse pregnancy outcomes in women with SAV, using a retrospective database, from seven medical centers of Korea. Based on the Carpenter-Coustan criteria using two-step approach, pregnancy and postpartum outcomes were compared, among normoglycemic, SAV, and gestational diabetes mellitus (GDM) groups. Among 9353 women, 342 (3.66%) and 418(4.47%) women were included in SAV and GDM groups, respectively. SAV and GDM groups showed significantly higher rates of postpartum T2DM than normoglycemic group (7.60%, 14.83%, and 1.82%, respectively, p < 0.001). And SAV group showed significantly higher rates of pregnancy associated hypertension, preterm birth, and neonatal hypoglycemia and sepsis, compared to normoglycemic group (neonatal sepsis, p = 0.008; the others, p < 0.001). In multivariate analysis, postpartum T2DM was associated with SAV, GDM (with/without insulin), nulliparity, pre-pregnancy BMI, chronic hypertension, hyperlipidemia, and DM family history. A scoring model to predict postpartum T2DM within 5 years, achieved an area under the curve of 0.74. This study demonstrated that not only GDM, but also SAV is a significant risk factor for postpartum T2DM.