Low-Carbohydrate Diets for Gestational Diabetes

Short-term effect of plant-based Nordic diet versus carbohydrate-restricted diet on glucose levels in gestational diabetes - the eMOM pilot study

BACKGROUND

The optimal nutritional treatment for gestational diabetes (GDM) is still a matter of debate. With increasing rates of GDM and potential negative consequences for the health of mother and child, the best treatment should be established. The Nordic diet with emphasis on plant-based protein show promising health outcomes in other populations but has yet to be investigated in GDM population. The aim of this study, which is part of the "Effect of plant-based Nordic diet versus carbohydrate-restricted diet on glucose levels in gestational diabetes" (eMOM) pilot study was to compare the short-term effects of healthy Nordic diet (HND) and the currently recommended moderate restriction of carbohydrates diet (MCRD) on glucose and lipid metabolism in women with GDM.

METHODS

This was a randomized crossover where each of the diet interventions (HND and MCRD) were consumed for 3 days with a 3-day wash-out period in between. In total, 42 pregnant women diagnosed with GDM (< 29 + 0 gestational week) were randomized. Glucose data was collected by continuous glucose monitors (CGM, Freestyle Libre®, Abbott, USA) worn for 14 days, and participants gave blood samples before and after diet interventions. The primary outcome was time spent in glucose target range (TIR, < 7.8 mmol/L). TIR, 3-day mean tissue glucose as well as changes in fasting glucose, homeostatic model of insulin resistance (HOMA-IR) and blood lipids were analyzed with paired samples statistical analyses.

RESULTS

Thirty-six women with complete 14 days CGM data were analyzed. Both diet interventions produced a high degree of TIR (99% SD 1.8), without a difference between the diets (p = 0.727). The 3-day mean glucose was significantly lower in HND than in MCRD (p = 0,049). Fasting insulin (p = 0,034), insulin resistance (p = 0,030), total and LDL cholesterol (p = 0,023 and 0,008) reduced more in the MCRD diet than the HND. NS differences in any other measure of CGM or blood tests.

CONCLUSIONS

HND and MCRD did not differ in terms of their short-term effect on TIR. A larger study with sufficient power is needed to confirm the differences in short-term mean glucose, insulin resistance and lipid metabolism.

TRIAL REGISTRATION

Registered in clinicaltrials.gov (21/09/2018, NCT03681054).

Supports and Barriers to Lifestyle Interventions in Women with Gestational Diabetes Mellitus in Australia: A National Online Survey

BACKGROUND

Gestational diabetes mellitus (GDM) affects approximately one in six pregnancies, causing a significant burden on maternal and infant health. Lifestyle interventions are first-line therapies to manage blood glucose levels (BGLs) and prevent future cardiometabolic complications. However, women with GDM experience considerable barriers to lifestyle interventions; thus, the aim of this study was to determine how women with GDM manage their condition and to identify the primary supports and barriers to lifestyle intervention participation.

METHODS

An online cross-sectional survey of women in Australia with a history of GDM was conducted. Questions included participant demographics, strategies used to manage BGLs, physical activity and dietary habits, and barriers and supports to lifestyle interventions.

RESULTS

A total of 665 individuals consented and responded to the advertisement, of which 564 were eligible and provided partial or complete responses to the survey questions. Most respondents were between 35 and 39 years of age (35.5%), not pregnant (75.4%), working part-time (26.7%), university-educated (58.0%), and had only one child (40.1%). Most respondents managed their BGLs through diet (88.3%), with "low-carbohydrate" diets being the most popular (72.3%), and 46.2% of respondents were undertaking insulin therapy. Only 42.2% and 19.8% of respondents reported meeting the aerobic and strengthening exercise recommendations, respectively. Women with one child or currently pregnant expecting their first child were 1.51 times more likely (95% CI, 1.02, 2.25) to meet the aerobic exercise recommendations than those with two or more children. The most common reported barriers to lifestyle intervention participation were "lack of time" (71.4%) and "childcare" commitments (57.7%). Lifestyle interventions delivered between 6 and 12 months postpartum (59.0%), involving an exercise program (82.6%), and delivered one-on-one were the most popular (64.9%).

CONCLUSION

Most women report managing their GDM with lifestyle strategies. The most common strategies reported involve approaches not currently included in the clinical practice guidelines such as reducing carbohydrate consumption. Furthermore, despite being willing to participate in lifestyle interventions, respondents report significant barriers, including lack of time and childcare commitments, whereas mentioned supports included having an online format. Lifestyle interventions for women with a history of GDM should be designed in a manner that is both tailored to the individual and considerate of existing barriers and supports to participation.

Carbohydrate intake quality and gestational diabetes mellitus, and the modifying effect of air pollution

Background

Nutritional management is the cornerstone of gestational diabetes mellitus (GDM) prevention. High quality instead of low quantity of carbohydrate intake has been paying attention in controlling glycemia. Air pollution exposure can be interacted with dietary sourced nutrients, which may modify the associations with GDM. This study aims to explore the associations between overall quality of carbohydrate intake and GDM as well as the modifying effect of prenatal air pollution exposure.

Methods

Carbohydrate quality index (CQI) was calculated was calculated by summing scores of the four components; Land use regression prediction models were used to assess the air pollution exposure levels. GDM definition was based on 75 g glucose tolerance test results. Associations between pre-pregnancy CQI, pre-natal air pollution as well as the modifying effect on GDM were explored based on a birth cohort in China.

Results

A total of 3,183 participants were included, of which 784 (24.63%) were diagnosed with GDM. Higher pre-pregnancy CQI was associated with a lower incidence of GDM [odds ratio (OR) = 0.75, 95% confidence interval (CI): 0.56-0.99, P _{for trend} = 0.04], especially for higher fasting blood glucose related GDM (OR = 0.66, 95% CI: 0.47, 0.91). Higher air pollution exposure before and during pregnancy was associated with a greater risk of GDM. Higher exposure to particulate matter with an aerodynamic diameter of < 2.5 μm (P _{for interaction} < 0.01), particulate matter with an aerodynamic diameter of < 10 μm (P _{for interaction} < 0.01), and sulfur dioxide (P _{for interaction} = 0.02) during pregnancy decreased the beneficial effect of high pre-pregnancy CQI on GDM.

Conclusion

CQI related dietary interventions pre-pregnancy to prevent GDM incidence should be considered. Women who are planning to be pregnant should avoid high exposure to air pollution during pregnancy.

Gestational Diabetes Mellitus and Antenatal Corticosteroid Therapy-A Narrative Review of Fetal and Neonatal Outcomes

BACKGROUND

There, we review the pathogenesis of gestational diabetes mellitus (GDM), its influence on fetal physiology, and neonatal outcomes, as well as the usage of antenatal corticosteroid therapy (ACST) in pregnancies complicated by GDM.

METHODS

MEDLINE and PubMed search was performed for the years 1990-2022, using a combination of keywords on such topics. According to the aim of the investigation, appropriate articles were identified and included in this narrative review.

RESULTS

GDM is a multifactorial disease related to unwanted pregnancy course and outcomes. Although GDM has an influence on the fetal cardiovascular and nervous system, especially in preterm neonates, the usage of ACST in pregnancy must be considered taking into account maternal and fetal characteristics.

CONCLUSIONS

GDM has no influence on neonatal outcomes after ACST introduction. The ACST usage must be personalized and considered according to its gestational age-specific effects on the developing fetus.

Gestational weight gain influences neonatal outcomes in women with obesity and gestational diabetes

INTRODUCTION

Obesity and gestational diabetes mellitus (GDM) are associated with an increased risk of perinatal complications and obesity in the offspring. However, the impact of gestational weight gain (GWG) on maternal and foetal outcomes is controversial.

PATIENTS AND METHODS

Retrospective study of 220 women with GDM and pre-pregnancy body mass index (BMI)>30kg/m². Pregnant women were classified according to the Institute of Medicine (IOM) recommendations regarding their prior BMI and GWG. We evaluated the impact of GWG on perinatal and obstetric outcomes.

RESULTS

Mean maternal age was 34.7±5.3 years. Pre-pregnancy obesity was classified as class I in 55.3% of the cases, class II in 32.0% and class III in 12.7%. GWG was adequate (5-9kg) in 24.2%, insufficient (<5kg) in 41.8% and excessive (>9kg) in 34.2%. Birth weight was within normal range in 81.9%, 3.6% were small for gestational age (microsomia) and 14.4% were large for gestational age (macrosomia). Insufficient GWG was associated with a higher rate of microsomal offspring, excessive GWG was associated to macrosomia and adequate GWG with normal birth weight.

CONCLUSION

GWG in women with pre-pregnancy obesity and GDM impacts neonatal birthweight. Insufficient GWG is associated with microsomia and excessive GWG is associated with macrosomia. Women with adequate GWG according to the IOM guidelines obtained better perinatal outcomes.

Effect of Carbohydrate-Restricted Dietary Pattern on Insulin Treatment Rate, Lipid Metabolism and Nutritional Status in Pregnant Women with Gestational Diabetes in Beijing, China

Carbohydrates play an important role in blood glucose control in pregnant women with GDM. Carbohydrate-restricted dietary (CRD) pattern for gestational diabetes mellitus (GDM) has been widely used in clinics, but the change in insulin utilization rate beyond CRD intervention in GDM remains unclear. The aim of the present study was to explore the application of insulin in pregnancy with GDM, as well as the influence of CRD pattern on lipid metabolism and nutritional state. A retrospective study of 265 women with GDM who delivered in Peking University People’s Hospital from July 2018 to January 2020 was conducted using a questionnaire survey. Women were divided into a CRD group or a control group according to whether they had received CRD intervention during pregnancy. There was no statistically significant difference in the rate of insulin therapy between the two groups (p > 0.05), the initial gestational week of the CRD group combined with insulin treatment was significantly higher than that of the control group (p < 0.05), and the risk of insulin therapy was positively correlated with fasting plasma glucose (FPG) in early pregnancy (p < 0.05). The incidence of abnormal low-density lipoprotein cholesterol levels in the CRD group was significantly lower than that in the control group (p < 0.05). There were no significant differences in nutritional indexes between the two groups. The results indicate that CRD intervention may be effective in delaying the use of insulin and improving the blood lipids metabolism during GDM pregnancy, while nutritional status may not be significantly affected under CRD intervention, and a high FPG in early pregnancy with GDM may be a risk factor for combined insulin therapy with CRD intervention.

The Perspectives of Diabetes Educators and Dietitians on Diet and Lifestyle Management for Gestational Diabetes Mellitus: A Qualitative Study

This study explores the knowledge and practice of diabetes educators and dietitians on diet and lifestyle management in women with gestational diabetes mellitus (GDM). Diabetes educators and dietitians were recruited from three maternity hospitals in Adelaide (Australia), through snowball and purposive sampling. Thirteen semistructured interviews were conducted, audio recorded, transcribed verbatim, and analysed for codes and themes. Four themes emerged: guidelines and resources, dietary intervention, management delivery, and communication. Diabetes educators and dietitians demonstrated consistent knowledge of nutritional management for GDM and uniform delivery methods. However, a lack of culturally diverse resources was highlighted, along with a lack of continuity of care across the multidisciplinary team. Barriers towards uptake of dietary intervention were reflected by diabetes educators and dietitians as women showing signs of guilt and stress and disengaging from the service. Further exploration on the knowledge and practice of diabetes educators and dietitians for GDM to best inform implementation strategies for knowledge translation of nutritional management is needed. The indication of language and cultural barriers and resources highlight an ongoing key priority area to support the care of women of ethnic minorities.

Dietary Intake in Early Pregnancy and Glycemia in Late Pregnancy among Women with Obesity

Women with obesity have increased risk for hyperglycemia during pregnancy, with negative health consequences for mother and child. We aimed to investigate adherence to nutritional recommendations in early pregnancy and to examine associations between early pregnancy dietary intake and late pregnancy glycemia among women with obesity. We included 120 women with pre-pregnancy body mass index (BMI) ≥30 kg/m² who participated in one of two randomized controlled trials. The participants completed a food frequency questionnaire in early pregnancy (gestational weeks 12–22). Fasting and 120 min glucose tolerance after ingestion of 75 g glucose were assessed in late pregnancy (gestational weeks 32–37). About 90% of the participants reported early pregnancy diary intake within the recommendations. Average intakes of vitamin D, iron, and folate were below recommended levels. High intakes of dairy products and protein in early pregnancy were associated with lower fasting glucose in late pregnancy, whereas high intake of bread was associated with lower 120 min glucose. There were no clear associations between single dietary variables and gestational diabetes mellitus (GDM) diagnosis in late pregnancy. In conclusion, some early pregnancy dietary variables were associated with late pregnancy glycemia. Potential causality of these findings should be investigated in future studies.

The risk of small and large for gestational age newborns in women with gestational diabetes according to pre-gestational body mass index and weight gain

AIM

To explore the effects of pregestational body mass index (BMI) and gestational weight gain (GWG) on maternal and neonatal outcomes of women with gestational diabetes mellitus (GDM).

METHODS

We conducted retrospective cohort analyses of outcomes among women with GDM who delivered at Shamir Medical Center, Israel (2017-2018).

RESULTS

We included 673 women with GDM in our analysis, 217 (32.24%) with appropriate GWG (aGWG), 247 (36.7%) with excessive GWG (eGWG), and 209 (31%) with insufficient GWG (iGWG). Cesarean section (CS) was less prevalent among women with iGWG (19.6%), compared with women with eGWG (31.2%) and aGWG (31.1%) (p = .008). Small for gestational weight (SGA) newborns were more prevalent in women with iGWG 9.1%, compared with 2% and 0.9% for women with eGWG and aGWG, respectively (p<.001). Large for gestational age (LGA) newborns were significantly more prevalent in women with eGWG 17.4% compared with 4.8% and 9.7% in patients with iGWG and aGWG women, respectively (p<.001). SGA and LGA newborns were more prevalent in women with iGWG and e-GWG across all pre-gestational BMI groups >18.5 kg/m².

CONCLUSIONS

A complex interplay exists between pregestational weight, GWG, and GDM and pregnancy outcomes, specifically SGA and LGA newborns. A strict follow-up considering the pregestational BMI, GWG, blood glucose levels, treatment modality, and fetal abdominal circumference could assist in managing the complex interplay of patients with GDM for better neonatal outcomes.

Higher Serum Bilirubin Levels in Response to Higher Carbohydrate Intake During Early Pregnancy and Lower Gestational Diabetes Mellitus Occurrence in Overweight and Obese Gravidae

Background and Aim: Serum bilirubin levels are recently shown to be a novel protector of gestational diabetes mellitus (GDM), yet whether they could be affected by carbohydrate quality is unclear. We aimed to examine the associations between dietary carbohydrate parameters and serum bilirubin levels during early pregnancy, with further exploration on a potential mediating role of serum bilirubin levels on carbohydrate parameters-GDM pathways. Methods: 260 healthy but overweight or obese gravidae (BMI ≥24 kg/m2) derived from a historical cohort in two hospitals in China were included. The associations between carbohydrate parameters (total carbohydrate intake, glycemic index GI, fiber intake, glycemic load GL) and serum bilirubin levels (total bilirubin, TB and direct bilirubin, DB) and GDM were evaluated by multivariable regression analysis. Generalized structural equation modeling was then applied to perform adjusted mediation analysis. Results: Increased serum bilirubin levels (mmol/L) and decreased GDM occurrence were observed following dietary carbohydrate intake (%E) and GL (g/1,000 kcal) in highest tertile compared to the lowest tertile [carbohydrate: TB: β = 0.926 (95%CI: 0.069, 1.782), DB: β = 0.554 (95%CI: 0.192, 0.916);GL:TB: β = 1.170 (95%CI: 0.339, 2.001); DB: β = 0.369 (95%CI: 0.016, 0.700); carbohydrate: adjusted OR = 0.43 (95%CI:0.19-0.99); GL: adjusted OR = 0.36 (95%CI:0.16, 0.84)]. The mediating effect of carbohydrate intake and GL on GDM through bilirubin levels was evaluated as modest (carbohydrate: 6.2% for TB, 1.3% for DB; GL: 8.7% for TB, 2.3% for DB). No association was observed regarding GI and fiber. Conclusions: Mildly elevated serum bilirubin levels appeared to be in response to higher energies consumed from carbohydrate during early pregnancy in healthy overweight or obese gravidae. However, the mediating effect of bilirubin levels on carbohydrate-GDM pathways is not evident. Larger investigation is further needed for solid evidence.

Ketones in Pregnancy: Why Is It Considered Necessary to Avoid Them and What Is the Evidence Behind Their Perceived Risk?

Current dietary advice for women with gestational diabetes mellitus is to avoid diets that result in elevated ketone levels. This guidance stems from a concern that maternal ketones are associated with poor fetal and childhood outcomes, including reduced childhood intelligence quota. The evidence behind these guidelines is conflicting and inconsistent. Given that dietary counseling is the initial treatment strategy for women with diabetes in pregnancy, it is important that clinicians understand the concern regarding maternal ketones. This review examines the physiology of ketogenesis in pregnancy, the prevalence of elevated maternal ketone levels, and the relationship between maternal ketones and fetal and childhood outcomes.

Use of the 50-g glucose challenge test to predict small-for-gestational-age neonates

BACKGROUND

To determine a cutoff value for the 50-g glucose challenge test (50-g GCT) for the prediction of small-for-gestational-age (SGA) neonates.

METHODS

This retrospective cohort study was conducted among pregnant women who were screened with the 50-g GCT at Hacettepe University Hospital between 1 January 2016 and 31 March 2019. Patients with 50-g GCT values <74 mg/dL (<10th percentile) served as the study group (n = 244), while patients with 50-g GCT values between 74 to 139 mg/dL served as the control group (n = 3104). Groups were compared in terms of demographic features, clinical characteristics, and obstetric outcomes. Logistic regression analysis was used to determine independent predictors of SGA. Receiver operating characteristic curves were used to assess the performance of 50-g GCT values in predicting SGA.

RESULTS

Lower birthweight, birthweight percentile, and 5th-minute Apgar values, together with higher rates of SGA, were observed in the study group (P < .001 for all). A 50-g GCT value below the 10th percentile (odds ratio: 3.29, 95% CI: 2.31-4.69, P < .001) was a significant independent factor for SGA. A cutoff value of 89.5 mg/dL (84.9% sensitivity, 85.6% specificity) was determined for SGA.

CONCLUSIONS

Low 50-g GCT values (<89.5 mg/dL) may be an early indicator for SGA.

Games and Health Education for Diabetes Control: A Systematic Review with Meta-Analysis

Finding methods to improve people's diabetes control and management is important to prevent its complications and maintain the quality of life. The aim of this review was to assess the effect of games on the blood glucose level (glycated hemoglobin (HbA1c)). A systematic review and meta-analysis were made. Pubmed, Scopus, and CINAHL databases were consulted in July of 2020. Ten studies were selected as a final sample, most of them being clinical trials using games to improve diabetes control. Half of the studies had samples between 8 and 14.9 years old and the other half between 57 and 65 years old. The studies informed about using applications/games for mobile phones, game consoles, and board games for diabetes education and management. The meta-analysis was performed with 4 studies showing a mean difference of 0.12 (CI 95% 0.57, 0.33) of HbA1c in favor of the intervention group with p > 0.05. Games are positive for diabetes health education and promoting healthier lifestyle, but their impact on HbA1c is low.

Large for Gestational Age and Risk for Academic Delays and Learning Disabilities: Assessing Modification by Maternal Obesity and Diabetes

The objective of this study was to examine academic delays for children born large for gestational age (LGA) and assess effect modification by maternal obesity and diabetes and then to characterize risks for LGA for those with a mediating condition. Cohort data were obtained from the New York City Longitudinal Study of Early Development, linking birth and educational records (n = 125,542). Logistic regression was used to compare children born LGA (>90th percentile) to those born appropriate weight (5-89th percentile) for risk of not meeting proficiency on assessments in the third grade and being referred to special education. Among children of women with gestational diabetes, children born LGA had an increased risk of underperforming in mathematics (ARR: 1.18 (95% CI: 1.07-1.31)) and for being referred for special education (ARR: 1.18 (95% CI: 1.02-1.37)). Children born LGA but of women who did not have gestational diabetes had a slightly decreased risk of academic underperformance (mathematics-ARR: 0.94 (95% CI: 0.90-0.97); Language arts-ARR: 0.96 (95% CI: 0.94-0.99)). Children born to women with gestational diabetes with an inadequate number of prenatal care visits were at increased risk of being born LGA, compared to those receiving extensive care (ARR: 1.67 (95% CI: 1.20-2.33)). Children born LGA of women with diabetes were at increased risk of delays; greater utilization of prenatal care among these diabetic women may decrease the incidence of LGA births.

Using a Mobile-based Nutritional Intervention Application Improves Glycemic Control but Reduces the Intake of Some Nutrients in Patients with Gestational Diabetes Mellitus: A Case Series Study

The prevalence of gestational diabetes mellitus (GDM) has been increasing worldwide, as has the economic cost associated with this condition. GDM threatens the health of the mother and child, and thus proper monitoring and management are essential. Mobile healthcare services have been applied to manage some diseases, particularly chronic diseases. We aimed to evaluate the utility of a mobile application in nutritional intervention by observing cases of a mobile application in a series of patients with GDM. We provided a mobile-based intervention to GDM patients and collected biochemical and nutritional information. The mobile-based nutritional intervention was effective in controlling carbohydrate intake and improving blood glucose level for patients with GDM.

Effects of Nutrient Intake during Pregnancy and Lactation on the Endocrine Pancreas of the Offspring

The pancreas has an essential role in the regulation of glucose homeostasis by secreting insulin, the only hormone with a blood glucose lowering effect in mammals. Several circulating molecules are able to positively or negatively influence insulin secretion. Among them, nutrients such as fatty acids or amino acids can directly act on specific receptors present on pancreatic beta cells. Dietary intake, especially excessive nutrient intake, is known to modify energy balance in adults, resulting in pancreatic dysfunction. However, gestation and lactation are critical periods for fetal development and pup growth and specific dietary nutrients are required for optimal growth. Feeding alterations during these periods will impact offspring development and increase the risk of developing metabolic disorders in adulthood, leading to metabolic programming. This review will focus on the influence of nutrient intake during gestation and lactation periods on pancreas development and function in offspring, highlighting the molecular mechanism of imprinting on this organ.

GDM and Nutrition-Answered and Unanswered Questions-There's More Work to Do!

Gestational Diabetes Mellitus (GDM) is the commonest medical pregnancy complication, and a growing problem around the world as the obesity epidemic continues. Ways to prevent GDM are urgently required, the management of GDM still poses many unanswered questions, and the postpartum prevention of the progression of GDM to type 2 diabetes remains a challenge. With GDM, the impact of any intervention on the offspring is always a major concern. Nutritional interventions come to the fore as one of our few levers in reducing the short-term pregnancy risk and long-term cardiometabolic risks to both mother and child. This special issue reports on the relationship between several nutrients and foods and the development and management of GDM, behavioural strategies to enhance lifestyle choices, the issues raised by prior bariatric surgery and ways to screen for GDM. The work identifies further unanswered questions over nutritional strategies to reduce the impact of GDM.