Macronutrient Composition or Social Determinants? Impact on Infant Outcomes With Gestational Diabetes Mellitus

Effects of Dietary Approaches and Exercise Interventions on Gestational Diabetes Mellitus: A Systematic Review and Bayesian Network Meta-analysis

Although lifestyle interventions are recommended as the frontline therapeutic strategy for women with gestational diabetes mellitus (GDM), the optimal dietary regimen or form of exercise has yet to be definitively established. We aimed to compare the effectiveness of lifestyle therapies for GDM. Four databases (PubMed, Web of Science, EMBASE, and Cochrane Library) were systematically searched by multiple researchers for randomized controlled trials (RCTs). RCTs comparing lifestyle therapies to treat GDM with control or another treatment were included. Data extraction and synthesis were performed, estimating mean differences (MDs) or relative risk (RR) through pair-wise and network meta-analysis with a randomized or fixed-effects model when appropriate. The primary outcomes were maternal glucose control, birth weight of newborns, macrosomia and preterm birth rate, and rate of need for insulin therapy. In total, 39 trials with information obtained from 2712 women assessed 15 treatments. After sensitivity analysis, we confirmed the dietary approaches to stop hypertension (DASH) diet [MD: -11.52; 95% credible intervals (CrIs): -14.01, -9.07, very low certainty of evidence (CoE)] and low glycemic index (GI) diets (MD: -6.3; 95% CrI: -9.9, -2.7, low CoE) have shown significant advantages in fasting plasma glucose and 2-h postprandial glucose control, respectively. Furthermore, the DASH diet and resistance exercise reduced insulin requirements independently by 71% (95% CrI: 52%, 84%) and 67% (95% CrI: 48%, 85%), respectively. Additionally, both the DASH (MD: -587.6; 95% CrI: -752.12, -421.85, low CoE) and low GI diets (MD: -180.09, 95% CrI: -267.48, -94.65, low CoE) reduced birth weight significantly, with the DASH diet also demonstrating effects in reducing macrosomia by 89% (95% CrI: 53%, 98%) and lowering the cesarean section rate by 46% (95% CI: 27%, 60%). However, exercise did not affect infant outcomes. Our findings suggest that the DASH diet and low GI diet and resistance exercise may be beneficial for maternal outcomes in pregnancies with GDM. The impact on infants is primarily observed through dietary interventions. Future research, characterized by higher quality and evidence grades, is necessary to complement and substantiate our findings. This study was registered with PROSPERO as CRD 42024527587.

Effects of different dietary patterns during pregnancy on birth outcomes and glucose parameters in women with gestational diabetes mellitus: A systematic review and meta-analysis

PURPOSE

Dietary interventions are the cornerstone of gestational diabetes mellitus (GDM) treatment. This study aimed to evaluate the effects of dietary patterns during pregnancy on birth outcomes and glucose parameters in women with GDM.

METHODS

PubMed, Embase, and The CoChrane Library were searched from the time of database creation to November 30, 2021, along with manual searches. Data analyses were performed using Stata 15.4 software.

RESULTS

From 2461 studies, 27 RCTs involving 1923 women were eligible. The pooled results showed that dietary pattern interventions during pregnancy reduced birth weight (WMD: -0.14 kg; 95% CI: -0.24, -0.00), hemoglobin A_1 C (HbA_1 C) (WMD: -0.19, 95% CI: -0.34, -0.05), and macrosomia incidence (RR 0.65 [95% CI 0.48, 0.88]). Low glycemic index (GI) diet reduced macrosomia incidence (RR 0.31 [95% CI 0.11, 0.93]) and fasting plasma glucose (FPG) levels (WMD: -0.10 mmol/L; 95% CI: -0.14, -0.05); a low carbohydrate (CHO) diet reduced large for gestational age (LGA) incidence (RR 0.33 [95% CI 0.13, 0.82]) and HbA_1 C (WMD: -0.32; 95% CI: -0.51, -0.14); dietary approaches to stop hypertension (DASH) diet reduced birth weight (WMD:-0.59 kg; 95% CI: -0.64, -0.55), insulin use (RR 0.31 [95% CI 0.18, 0.56), macrosomia incidence (RR 0.12 [95% CI 0.03, 0.50]), and cesarean sections incidence (RR 0.57 [95% CI 0.40, 0.82]).

CONCLUSION

Dietary patterns during pregnancy can improve certain birth outcomes and glycemic parameters. Due to limitations in the quality and number of included studies, the above findings still need to be validated by further randomized controlled trials with high quality and large samples.

Increased Protein with Decreased Carbohydrate Intake Reduces Postprandial Blood Glucose Levels in Women with Gestational Diabetes: The iPRO Study

Introduction

There is an urgent need to establish an evidence base for recommendations regarding proportions of macronutrients for optimized nutritional management of gestational diabetes mellitus (GDM). Our study compared isocaloric diets in women with GDM that differed in protein and carbohydrate content with fats held constant. We hypothesized that the glucose area under the curve (AUC) would be lower with the higher protein/lower carbohydrate diet.

Research Design and Methods

This study used a random order crossover design within a controlled research unit environment. Nineteen women were randomized to treatment, with 12 participants completing both arms of the study. Blood sampling occurred preprandially and at t = 30, 60, 120, and 180" relative to meals. Inclusion criteria were confirmed diet-controlled GDMA1, singleton gestation, and with no pre-existing medical comorbidities. Mean gestational age at entrance to study = 32 (±1.76) weeks. Mean prepregnant body mass index of participants = 28.7 (±5.3) kg/m2 Participants were randomly assigned initially to either an increased protein/low carbohydrate (iPRO30%/CHO35%) diet or a lower protein/higher carbohydrate (LPRO15%/CHO50%) diet for a 36 hour inpatient stay on the research unit. All meals and snacks were prepared in a metabolic kitchen. After a 3-7 day washout period, participants were randomized to the opposite treatment.

Results

On day 2 (with confirmed overnight fasting), the average 3-hour pre- through postprandial glucose AUC was lower in iPRO30%/CHO35% treatment arm (17395.20 ± 2493.47 vs. 19172.47 ± 3484.31, p = 0.01).

Conclusion

This study is the first to demonstrate that a higher protein, lower carbohydrate meal, especially at breakfast, can result in lower postprandial blood glucose values in women with gestational diabetes. A lack of statistically significant differences at other collection time points could have been due to several factors, but most likely due to small sample size. Longer term outcomes of a higher protein diet, including maternal glycemic control, nitrogen balance, and impact on fetal growth outcomes, are needed.

Lifestyle intervention during pregnancy in patients with gestational diabetes mellitus and the risk of neonatal hypoglycemia: A systematic review and meta-analysis

Objective

Neonatal hypoglycemia is a severe adverse consequence of infants born to mothers with gestational diabetes mellitus (GDM), which can lead to neonatal mortality, permanent neurological consequences, and epilepsy. This systematic review and meta-analysis of randomized controlled trials (RCTs) was conducted to explore the effect of lifestyle intervention during pregnancy in women with GDM on the risk of neonatal hypoglycemia.

Methods

PubMed, Web of Science, Cochrane Library, CINAHL, and SPORTDiscus databases were searched by 1st April 2022. Data were pooled as the risk ratio (RR) with 95% CIs of neonatal hypoglycemia. Random-effects, subgroup analyses, meta-regression analysis, and leave-one-out analysis were conducted, involving 18 RCTs.

Results

Prenatal lifestyle intervention could significantly reduce the risk of neonatal hypoglycemia (RR: 0.73, 95% CI: 0.54-0.98, P = 0.037). Subgroup analysis further demonstrated that the reduced risk of neonatal hypoglycemia was observed only when subjects were younger than 30 years, initiated before the third trimester, and with dietary intervention. Meta-regression analysis revealed that the risk of neonatal hypoglycemia post lifestyle intervention was lower in mothers with lower fasting glucose levels at trial entry.

Conclusion

We found that prenatal lifestyle intervention in women with GDM significantly reduced the risk of neonatal hypoglycemia. Only lifestyle intervention before the third trimester of pregnancy, or dietary intervention only could effectively reduce the risk of neonatal hypoglycemia. Future studies are required to explore the best pattern of lifestyle intervention and to determine the proper diagnostic criteria of GDM in the first/second trimester of pregnancy.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/#myprospero, PROSPERO, identifier: CRD42021272985.

An evaluation of dietary intakes of a selected group of South Asian migrant women with gestational diabetes mellitus

Background: Women of South Asian descent have an increased risk of developing gestational diabetes mellitus (GDM), and type 2 diabetes mellitus compared to Caucasian women. Dietary advice provided by health practitioners to this group has been found to be culturally inappropriate. The aim of this study was to describe the dietary intakes of South Asian women with gestational diabetes and use this information to develop culturally appropriate dietary models for education and support of dietary management.Method: An in-depth diet and lifestyle survey was administered with 13 eligible women. Dietary histories were collected for pre-pregnancy, during pregnancy and post-GDM diagnosis to evaluate changes in dietary intake, diet and health beliefs and traditional foods consumed during pregnancy.Results: The diets of participants did not meet nutrient requirements for pregnancy; specific areas on concern were dietary fibre, calcium, iron, folate and iodine. Vegetarians were particularly at risk with regards to energy and protein intake. Generally dietary intakes of these women with GDM were not consistent with guidelines for management of GDM. Confusion about what they should eat for GDM, health practitioner advice and conflict with cultural expectations about foods to consume during pregnancy was evident.Conclusion: The dietary information collected from these women was used to model sample menus for GDM that were culturally appropriate and consistent with vegetarian and non-vegetarian eating patterns.

Carbohydrate Content in the GDM Diet: Two Views: View 2: Low-Carbohydrate Diets Should Remain the Initial Therapy for Gestational Diabetes

IN BRIEF The appropriate dietary intervention for gestational diabetes mellitus (GDM) is not clear. Traditionally, a low-carbohydrate diet has been prescribed. Recently, there has been a movement to prescribe a diet higher in nutrient-dense carbohydrate as the initial treatment for GDM. At this time, there is insufficient outcome data to support this type of diet.