Lactation Duration and Long-term Risk for Incident Type 2 Diabetes in Women With a History of Gestational Diabetes Mellitus

Is Breastfeeding an Effective Approach to Reduce Metabolic Risk After GDM in Mothers and Infants?

Gestational diabetes mellitus (GDM) leads to increased lifelong cardiometabolic risk in both mothers and their offspring. The identification of effective strategies to contain the future risk of type 2 diabetes (T2D) and cardiovascular disease (CVD) is of utmost importance to reduce the burden of the disease. Breastfeeding (BF) is effective in reducing short- and long-term child morbidity. In recent years, BF has emerged as a candidate low-cost intervention to prevent future cardiometabolic complications both in mothers and infants exposed to GDM. The aim of this review is to provide an overview of the evidence about the possible metabolic benefits of BF for both mothers with a history of GDM and their offspring. Increasing evidence supports the positive effects of exclusive BF over formula feeding (FF) or mixed feeding on glucose homeostasis and the lipid profile in women with previous GDM in the early postpartum period. Studies with a longer observation suggest clear benefits of intensive and longer BF on the risk of diabetes and prediabetes in mothers after adjustment for confounders. In regards to infants, in most studies, the intensity and duration of BF are positively associated with slower infant growth curves compared with FF, indicating that the positive effect of BF on growth trends might contrast the increased risk of obesity and metabolic diseases observed in infants exposed to GDM. Considering these findings, a global effort should be made to support BF practice to possibly reduce cardiometabolic morbidity after GDM.

Lactation duration and the risk of type 2 diabetes mellitus in parous women: A perspective on socioeconomic status disparity

BACKGROUND & AIMS

Whether and how socioeconomic status (SES) influences the associations between type 2 diabetes mellitus (T2DM) and lactation remains unknown. We aimed to evaluate the associations between lactation duration and T2DM from a perspective of SES disparity.

METHODS

A total of 263,859 parous women without diabetes at baseline (2004-2008) in the China Kadoorie Biobank were included. Lactation duration was counted for the first-child, per-child and lifetime. The latent class analysis of education level, household income, occupation, and residence was conducted to derive SES as low, intermediate, and high. T2DM cases were identified through linkage with records in hospitals, disease registry system and health insurance data during follow-up (2008-2015). Multivariable Cox proportional hazards regression models were applied to estimate hazard ratios (HRs) and 95 % confidence intervals for T2DM. Population attributable fraction evaluated the cases tied to insufficient lactation by SES.

RESULTS

In a median 9.2-year follow-up, 8,204 cases were identified. Women who breastfed their first child for 12-24 and > 24 months respectively, had a reduced risk of diabetes (fully adjusted HR: 0.84 [0.75-0.94] and 0.81 [0.70-0.95]). Similar results were found for per-child (0.84 [0.72-0.98] and 0.71 [0.59, 0.85]), and lifetime lactation for > 36 months (0.66 [0.56, 0.77]). For dose-response associations, every 5-month increase in lactation duration (first-child, per-child, lifetime) was linked to a 7 %, 10 %, and 4 % lower T2DM risk. These associations were significant among low SES women but not for intermediate or high SES women. For low SES women, 36.42 % of diabetes cases were attributable to per-child lactation duration of < 24 months, and 5.76 %, 25.37 %, 47.29 %, 19.04 % of cases would be prevented if women lactating for 0, 0-6, 6-12, and 12-24 months extended their per-child lactation duration to at least 2 years.

CONCLUSION

Longer lactation duration is associated with a decreased risk of T2DM among women, especially those with low SES. The promotion of extended breastfeeding could potentially prevent a significant proportion of diabetes events.

Lipid signature changes of women with gestational diabetes mellitus in response to puerperal exclusive breastfeeding

OBJECTIVE

We here investigated whether lactation during puerperium could help to reverse the diabetogenic effect of gestation and further explored the lipid profiling changes upon breastfeeding.

METHODS

Thirty-five women diagnosed with GDM were recruited, and fasting plasma samples were collected at ~6 weeks postpartum. Maternal metabolic parameters were determined, and an untargeted lipidomic analysis was performed. The relationship between underlying lipidomic responses and lactation was explored.

RESULTS

Improved glucose homeostasis and insulin sensitivity were observed in GDM women who adopted breastfeeding during the puerperium. Further lipidomics analysis revealed prominent correlations between lipid constitution changes and breastfeeding in women with GDM. A total of 766 lipid species were identified, 33 of which were found to be significantly altered in response to lactation. Significant associations between dysregulated lipids and maternal metabolic parameters were also shown. Subsequently, we identified a panel of three lipids that were strongly associated with breastfeeding, from which we constructed a predictive model with higher discriminating power.

CONCLUSIONS

We generally revealed that lactation during puerperium appears to have favorable effects on diabetogenic risk factors for GDM women. We also discovered that lipidomic changes related to lactation could elucidate the mother's recovery from GDM pregnancy.

Individual and combined effects of muscle strength and visceral adiposity on incident prediabetes and type 2 diabetes in a longitudinal cohort of midlife Asian women

AIM

To investigate the independent and combined effects of muscle strength and visceral adiposity on prediabetes and type 2 diabetes incidence among midlife women.

MATERIALS AND METHODS

In this prospective study of midlife women (mean age 56.4 years), visceral adiposity, defined as visceral adipose tissue (VAT) >131 cm2 measured by dual energy X-ray absorptiometry, and poor combined muscle strength, defined as handgrip strength <18 kg and/or five-time repeated chair stand test performance ≥12 s, were determined at baseline between 2014 and 2016. After 6.6 years, the effects of VAT and muscle strength on risk of incident prediabetes (fasting blood glucose 5.6-6.9 mmol/L) and type 2 diabetes (fasting blood glucose levels ≥7 mmol/L, medication use, or physician diagnosis) were examined using modified Poisson regression analysis.

RESULTS

Among the 733 initially normoglycaemic participants, 150 (20.5%) developed prediabetes or type 2 diabetes. Women with both poor combined muscle strength and high VAT had the highest risk for both prediabetes and type 2 diabetes (adjusted relative risk [aRR] 2.63, 95% confidence interval [CI] 1.81-3.82). In comparison, high VAT alone increased risk by 1.78-fold (95% CI 1.12-2.84). Stratification analyses showed that among women with low muscle strength, high VAT demonstrated increased risks of prediabetes and type 2 diabetes (aRR 2.84, 95% CI 1.95-4.14) compared to those with normal strength (aRR 1.66, 95% CI 1.04-2.65).

CONCLUSIONS

Low combined muscle strength with high VAT poses a greater risk for the development of prediabetes and type 2 diabetes than high VAT alone. Muscle strengthening should be promoted alongside weight loss in diabetes prevention.

Breastfeeding frequency and incidence of type 2 diabetes among women with previous gestational diabetes compared to those without: a historical cohort study in the UK

BACKGROUND

There is a growing body of research to suggest that women with gestational diabetes are less likely to initiate and continue breastfeeding than those who have not had however findings are mixed. There is limited research in the UK assessing the frequency of breastfeeding in women with gestational diabetes, none reporting the association of breastfeeding with incidence of type 2 diabetes and existing research has not adequately adjusted for potential confounders. This study aims to assess frequency of breastfeeding among women with gestational diabetes compared to those without, and to explore how breastfeeding influences risk of future type 2 diabetes in women with gestational diabetes while adjusting for known confounders.

METHODS

Historical cohort study using routinely collected health care data from Fife and Tayside Health Boards, Scotland, UK including all women diagnosed with gestational diabetes between 1993 and 2015 and a matched comparator cohort (n = 4,968). Women with gestational diabetes were followed up until a diagnosis of type 2 diabetes, the end of the study, or date of death. Multinomial logistic regression was used to estimate odds ratios for breastfeeding for the whole sample and the association between breastfeeding and development of type 2 diabetes in women with gestational diabetes was assessed by Cox regression.

RESULTS

Women with a diagnosis of gestational diabetes, who were younger, overweight/obese or living in the most deprived areas were significantly less likely to exclusively breastfeed for a duration of longer than eight weeks. Risk of developing type 2 diabetes among women with gestational diabetes was significantly higher for those who exclusively breastfed less than 8 weeks, lived in the most deprived areas or had a family history of diabetes.

CONCLUSIONS

This study confirms the important role of a short duration of exclusive breastfeeding in protecting women with gestational diabetes against type 2 diabetes but highlights the challenges to breastfeeding in this group. Interventions are needed to support breastfeeding among women with gestational diabetes that are acceptable to younger, overweight/obese women living in deprived areas.

Maternal metabolic conditions as predictors of breastfeeding outcomes: Insights from an Australian cohort study

INTRODUCTION

Breastfeeding represents an important opportunity to optimize health outcomes for both mother and infant, particularly in the context of maternal metabolic conditions such as diabetes and polycystic ovary syndrome. However, evidence suggests that women affected by these conditions breastfeed at reduced rates and durations. Our aim was to use the large, prospective, community-based Australian Longitudinal Study on Women's Health (ALSWH) to conduct an in-depth exploratory analysis of breastfeeding outcomes in Australian women affected by key maternal metabolic conditions.

MATERIAL AND METHODS

Data from 12 920 pregnancies to 5605 women from the 1973-1978 birth cohort of the ALSWH were examined. Univariable and multivariable regression using generalized estimating equation models were applied to assess breastfeeding initiation and duration (outcome measures) in relation to key self-reported maternal metabolic diagnoses (pre-gestational type 1 and type 2 diabetes, gestational diabetes, and polycystic ovary syndrome; main explanatory variables). Key sociodemographic and clinical covariates were also considered.

RESULTS

Results showed no significant association between specific maternal metabolic diagnoses (pre-gestational or gestational diabetes, or polycystic ovary syndrome) and breastfeeding outcomes. However, maternal body mass index emerged as a key predictor of suboptimal breastfeeding outcomes. Pregnancies affected by maternal obesity were associated with a 2.1-fold increase in the odds of not initiating breastfeeding, after adjusting for other key variables (95% CI 1.67 to 2.60, p < 0.01). Maternal overweight and obesity were, respectively, associated with an adjusted 1.4-fold (95% CI 1.20 to 1.55, p < 0.01) and 1.8-fold increase (95% CI 1.60 to 2.10, p < 0.01) in the odds of a breastfeeding duration less than 6 months.

CONCLUSIONS

Maternal obesity, rather than any specific maternal metabolic condition, appears to be a key predictor of breastfeeding outcomes in Australian women.

Factors Influencing Delayed Onset of Lactogenesis: A Scoping Review

Purpose

Delayed onset of lactogenesis is a significant barrier to achieving the WHO-recommended 50% exclusive breastfeeding rate in the first six months. This study maps the main factors influencing this condition, addressing gaps in the current research landscape.

Methods

Following Arksey and O'Malley's scoping review framework, databases such as PubMed, Web of Science (WOS), Embase, Cochrane Library, CINAHL plus with full text, China National Knowledge Infrastructure (CNIK), Weipu Chinese Journal Service Platform (VIP), Wanfang Data Knowledge Service Platform, and China Biomedical Literature Database (CBM) were searched on February 1, 2023. Studies in Chinese and English involving pregnant and postpartum women, focusing on delayed onset of lactogenesis, were included without restrictions on publication date or geography.

Results

Forty-six studies published between 2002 and 2022 met the inclusion criteria, revealing variable incidences of delayed lactogenesis among different groups. Thirty-four influencing factors were identified and organized into five themes: maternal-infant characteristics, perinatal mental state, physical activity participation during pregnancy, breastfeeding behaviors, and medical staff interventions. Within eighteen major factors highlighted, factors such as age, pre-pregnancy BMI, gestational weight gain, average LATCH score within 24 hours postpartum, labor analgesia, sleep, frequency of postpartum breastfeeding, and timing of initial breast suckling/pumping showed inconsistent or conflicting conclusions.

Conclusion

High and variable incidences of delayed lactogenesis underline its multifactorial nature. Effective interventions require strong advocacy from healthcare professionals and adherence by pregnant women. Further research using standardized methods is essential to clarify inconsistent or conflicting findings on the influencing factors.

Prospective associations between breast feeding, metabolic health, inflammation and bone density in women with prior gestational diabetes mellitus

INTRODUCTION

The aim of the study is to investigate prospective associations between breastfeeding and metabolic outcomes, inflammation, and bone density in women with prior gestational diabetes mellitus (GDM).

RESEARCH DESIGN AND METHODS

We prospectively included 171 women with GDM from the MySweetheart trial. Women were followed during pregnancy (from 24 up to 32 weeks' gestational age) up to 1 year postpartum. Outcomes included weight, weight retention, body composition, insulin resistance and secretion indices, C reactive protein (CRP), and bone density. We compared differences in the associations between breastfeeding and health outcomes between women who breast fed <6 months vs ≥6 months. Analyses were adjusted for potential medical and sociodemographic confounders.

RESULTS

Breastfeeding initiation was 94.2% (n=161) and mean breastfeeding duration was 6.6 months. Breastfeeding duration was independently associated with lower weight, weight retention, body fat, visceral adipose tissue, lean mass, CRP, insulin resistance (Homeostatic Model Assessment for Insulin Resistance), and insulin secretion (Homeostatic Model Assessment of β-cell index) at 1 year postpartum (all p≤0.04) after adjusting for confounders. Breastfeeding was associated with higher insulin resistance-adjusted insulin secretion (Insulin Secretion-Sensitivity Index-2) in the unadjusted analyses only. There was no association between breastfeeding duration and bone density. Compared with <6 months, breastfeeding duration ≥6 months was associated with lower weight, weight retention, body fat, fat-free mass as well as lower CRP at 1 year postpartum (all p<0.05) after adjusting for confounders.

CONCLUSIONS

Longer breastfeeding duration among women with prior GDM was associated with lower insulin resistance, weight, weight retention, body fat and inflammation, but not lower bone density at 1 year postpartum. Breastfeeding for ≥6 months after GDM can help to improve cardiometabolic health outcomes 1 year after delivery.

Lactation duration and development of type 2 diabetes and metabolic syndrome in postpartum women with recent gestational diabetes mellitus

BACKGROUND

The World Health Organization and United Nations Children's Fund recommend exclusive breastfeeding (EBF) for the first six months of an infant's life. Although evidence suggests that maintaining breastfeeding has positive impacts on glucose and lipid metabolism in postpartum women with a history of gestational diabetes mellitus (GDM), no study has investigated whether such effects differ between breastfeeding intensities. This study aimed to evaluate the impact of maintaining breastfeeding on prediabetes, type 2 diabetes mellitus (T2DM), and metabolic syndrome (MetS) six months postpartum in women with GDM. This study also examined the potential variations in glucometabolic outcomes between EBF at six months and partial breastfeeding at six months.

METHODS

This prospective cohort study included 130 women with recent GDM who experienced live births between 7 September 2020 and 31 January 2023 at a university hospital in Bangkok, Thailand. All the women were free of T2DM and MetS at baseline (six weeks postpartum). We followed up these women six months postpartum to assess their breastfeeding practices (EBF at six months, partial breastfeeding at six months, or not maintaining breastfeeding) and evaluate their progression to prediabetes, T2DM, and MetS. Maintaining breastfeeding was defined as breastfeeding for six months. EBF was determined using the "recall since birth" method.

RESULTS

Of the 130 participants included, the rates of prediabetes, T2DM, and MetS six months postpartum were 33% (n = 43), 2% (n = 3), and 17% (n = 22), respectively. In the unadjusted model, maintaining breastfeeding was associated with a reduction in the risks of prediabetes and MetS but not T2DM. After adjusting for potential confounders, maintaining breastfeeding was a significant protective factor only for prediabetes. The adjusted risk ratios and 95% confidence intervals were 0.54 (0.29, 0.99) for prediabetes and 0.47 (0.19, 1.06) for MetS. When EBF at six months and partial breastfeeding at six months were separately analyzed, the risks of prediabetes and MetS differed between the two groups. In the EBF at six months-to-partial breastfeeding at six months comparison, the adjusted risk ratios (95% confidence intervals) of prediabetes and MetS were 0.46 (0.22, 0.97) vs. 0.79 (0.25, 2.49) and 0.34 (0.11, 0.99) vs. 0.69 (0.22, 2.07), respectively.

CONCLUSIONS

Maintaining breastfeeding reduced the risk of prediabetes and MetS, but not of T2DM, six months postpartum; these effects were significant only with EBF. These findings indicate that supporting maternal efforts to practice EBF for six months may improve women's health after GDM.

TRIAL REGISTRATION

Thai Clinical Trials Registry Registration No. TCTR20200902003. Date of registration: September 2, 2020. Date of initial participant enrollment: September 7, 2020.

Lifetime Duration of Breastfeeding and Cardiovascular Risk in Women With Type 2 Diabetes or a History of Gestational Diabetes: Findings From Two Large Prospective Cohorts

OBJECTIVE

Breastfeeding duration is inversely associated with risks of cardiovascular disease (CVD) and type 2 diabetes in parous women. However, the association among women at high risk, including women with type 2 diabetes or gestational diabetes mellitus (GDM) is unclear.

RESEARCH DESIGN AND METHODS

We included 15,146 parous women with type 2 diabetes from the Nurses' Health Study I and II (NHS, NHS II) and 4,537 women with a history of GDM from NHS II. Participants reported history of breastfeeding via follow-up questionnaires. Incident CVD by 2017 comprised stroke or coronary heart disease (CHD) (myocardial infarction, coronary revascularization). Adjusted hazard ratios (aHRs) and 95% CIs were estimated using Cox models.

RESULTS

We documented 1,159 incident CVD cases among women with type 2 diabetes in both cohorts during 188,874 person-years of follow-up and 132 incident CVD cases among women with a GDM history during 100,218 person-years of follow-up. Longer lifetime duration of breastfeeding was significantly associated with lower CVD risk among women with type 2 diabetes, with pooled aHR of 0.68 (95% CI 0.54-0.85) for >18 months versus 0 months and 0.94 (0.91-0.98) per 6-month increment in breastfeeding. Similar associations were observed with CHD (pooled aHR 0.93 [0.88-0.97]) but not with stroke (0.96 [0.91-1.02]) per 6-month increment in breastfeeding. Among women with GDM history, >18 months versus 0 months of breastfeeding was associated with an aHR of 0.49 (0.28-0.86) for total CVD.

CONCLUSIONS

Longer duration of breastfeeding was associated with lower risk of CVD in women with type 2 diabetes or GDM.

Women's reproductive risk and genetic predisposition in type 2 diabetes: A prospective cohort study

OBJECTIVE

To assess synergistic effects of reproductive factors and gene-reproductive interaction on type 2 diabetes (T2D) risk, also the extent to which the genetic risk of T2D can be affected by reproductive risk.

METHODS

84,254 women with genetic data and reproductive factors were enrolled between 2006 and 2010 in the UK Biobank. The reproductive risk score (RRS) was conducted based on 17 reproductive items, and genetic risk score (GRS) was based on 149 genetic variants.

RESULTS

There were 2300 (2.8 %) T2D cases during an average follow-up of 4.49 years. We found a significant increase in T2D risk across RRS categories (Ptrend < 0.001). Compared with low reproductive risk, high-mediate (adjusted hazard ratio [aHR] 1.38, 95 % CI 1.20-1.58) and high (aHR 1.84, 95 % CI 1.54-2.19) reproductive risk could increase the risk of T2D. We further observed a significant additive interaction between reproductive risk and genetic predisposition. In the situation of high genetic predisposition, women with low reproductive risk had lower risk of T2D than those with high reproductive risk (aHR 0.47, 95 % CI 0.30-0.76), with an absolute risk reduction of 2.98 %.

CONCLUSIONS

Our novo developed RRS identified high reproductive risk is associated with elevated risk of women's T2D, which can be magnified by gene-reproductive interaction.

Precision stratification of prognostic risk factors associated with outcomes in gestational diabetes mellitus: a systematic review

BACKGROUND

The objective of this systematic review is to identify prognostic factors among women and their offspring affected by gestational diabetes mellitus (GDM), focusing on endpoints of cardiovascular disease (CVD) and type 2 diabetes (T2D) for women, and cardiometabolic profile for offspring.

METHODS

This review included studies published in English language from January 1st, 1990, through September 30th, 2021, that focused on the above outcomes of interest with respect to sociodemographic factors, lifestyle and behavioral characteristics, traditional clinical traits, and 'omics biomarkers in the mothers and offspring during the perinatal/postpartum periods and across the lifecourse. Studies that did not report associations of prognostic factors with outcomes of interest among GDM-exposed women or children were excluded.

RESULTS

Here, we identified 109 publications comprising 98 observational studies and 11 randomized-controlled trials. Findings indicate that GDM severity, maternal obesity, race/ethnicity, and unhealthy diet and physical activity levels predict T2D and CVD in women, and greater cardiometabolic risk in offspring. However, using the Diabetes Canada 2018 Clinical Practice Guidelines for studies, the level of evidence was low due to potential for confounding, reverse causation, and selection biases.

CONCLUSIONS

GDM pregnancies with greater severity, as well as those accompanied by maternal obesity, unhealthy diet, and low physical activity, as well as cases that occur among women who identify as racial/ethnic minorities are associated with worse cardiometabolic prognosis in mothers and offspring. However, given the low quality of evidence, prospective studies with detailed covariate data collection and high fidelity of follow-up are warranted.

Breastfeeding Duration Is Associated with the Risk of Tooth Loss, Chewing Difficulty, and Undernutrition among Older Korean Women: Results of the Korea National Health and Nutrition Examination Survey (KNHANES) 2013-2015

We investigated whether older Korean women with prolonged breastfeeding duration have an increased risk of tooth loss, chewing difficulty, or undernutrition, as well as whether tooth loss and chewing difficulty mediate the association between breastfeeding duration and undernutrition risk. This study included 1666 women aged ≥65 years from the 2013-2015 Korea National Health and Nutrition Examination Survey who breastfed after delivery. The number of teeth and chewing ability were investigated based on the status of individual teeth and a self-report questionnaire, respectively. Dietary intake was estimated using the 24 h recall method. Compared with women who breastfed for 1-18 months, the odds ratios for tooth loss were 1.16 (95% confidence interval [CI] = 0.69-1.94), 1.79 (95% CI = 1.08-2.94), and 1.86 (95% CI = 1.16-2.97) among women who breastfed for 19-36, 37-72, and ≥73 months, respectively (p for trend = 0.004). Similar results were obtained for chewing difficulty and undernutrition. Furthermore, tooth loss and chewing difficulty partially mediated the association between breastfeeding duration and undernutrition risk. In conclusion, older Korean women who breastfed for longer periods are more likely to experience tooth loss, chewing difficulty, and undernutrition, which are particularly severe among women who breastfed for ≥37 months. The association between breastfeeding duration and undernutrition risk is mediated by tooth loss and chewing difficulty.

Early postpartum HbA1c after hyperglycemia first detected in pregnancy-Imperfect but not without value

BACKGROUND

South African women of childbearing age are disproportionally affected by obesity and at significant risk of Type 2 Diabetes Mellitus (T2DM). Unless pregnant, they do not readily undergo screening for T2DM. With a local focus on improved antenatal care, hyperglycemia is often first detected in pregnancy (HFDP). This may erroneously be attributed to Gestational Diabetes Mellitus (GDM) in all without considering T2DM. Glucose evaluation following pregnancy is essential for early detection and management of women with T2DM in whom persistent hyperglycemia is to be expected. Conventional testing with an oral glucose tolerance test (OGTT) is cumbersome, prompting investigation for alternate solutions.

AIM

To compare the diagnostic performance of HbA1c to the current gold standard OGTT in women with HFDP 4-12 weeks post-delivery.

METHODS

Glucose homeostasis was assessed with OGTT and HbA1c in 167 women with HFDP, 4-12 weeks after delivery. Glucose status was based on American Diabetes Association criteria.

RESULTS

Glucose homeostasis was assessed at 10 weeks (IQR 7-12) after delivery. Of the 167 participants, 52 (31%) had hyperglycemia, which was comprised of 34 (20%) prediabetes and 18 (11%) T2DM. Twelve women in the prediabetes subgroup had diagnostic fasting plasma glucose (FPG) and 2-hour plasma glucose (2hPG), but in two-thirds of the patients (22/34) only one time point proved diagnostic. The FPGs and the 2hPGs of six women with HbA1c-based T2DM were both within the prediabetes diagnostic range. According to the HbA1c measurements, 85% of 52 participants with gold standard OGTT defined hyperglycemia (prediabetes and T2DM) as well as 15 of 18 women with postpartum persistent T2DM were correctly classified. According to FPG, 15 women with persistent hyperglycemia would have been missed (11 with prediabetes and four with T2DM; 29%). When compared to an OGTT, a single HbA1c of 6.5% (48mmol/mol) postpartum demonstrated a sensitivity of 83% and specificity of 97% for the identification of T2DM.

CONCLUSION

HbA1c may improve access to postpartum testing in overburdened clinical settings where the required standards of OGTT cannot be guaranteed. HbA1c is a valuable test to detect women who will benefit most from early intervention but cannot unequivocally replace OGTT.

Predictors and risk factors of short-term and long-term outcomes among women with gestational diabetes mellitus (GDM) and their offspring: Moving toward precision prognosis?

As part of the American Diabetes Association Precision Medicine in Diabetes Initiative (PMDI) - a partnership with the European Association for the Study of Diabetes (EASD) - this systematic review is part of a comprehensive evidence evaluation in support of the 2 nd International Consensus Report on Precision Diabetes Medicine. Here, we sought to synthesize evidence from empirical research papers published through September 1 st , 2021 to evaluate and identify prognostic conditions, risk factors, and biomarkers among women and children affected by gestational diabetes mellitus (GDM), focusing on clinical endpoints of cardiovascular disease (CVD) and type 2 diabetes (T2D) among women with a history of GDM; and adiposity and cardiometabolic profile among offspring exposed to GDM in utero. We identified a total of 107 observational studies and 12 randomized controlled trials testing the effect of pharmaceutical and/or lifestyle interventions. Broadly, current literature indicates that greater GDM severity, higher maternal body mass index, belonging to racial/ethnic minority group; and unhealthy lifestyle behaviors would predict a woman's risk of incident T2D and CVD, and an unfavorable cardiometabolic profile among offspring. However, the level of evidence is low (Level 4 according to the Diabetes Canada 2018 Clinical Practice Guidelines for diabetes prognosis) largely because most studies leveraged retrospective data from large registries that are vulnerable to residual confounding and reverse causation bias; and prospective cohort studies that may suffer selection and attrition bias. Moreover, for the offspring outcomes, we identified a relatively small body of literature on prognostic factors indicative of future adiposity and cardiometabolic risk. Future high-quality prospective cohort studies in diverse populations with granular data collection on prognostic factors, clinical and subclinical outcomes, high fidelity of follow-up, and appropriate analytical approaches to deal with structural biases are warranted.

Associations of ozone exposure with gestational diabetes mellitus and glucose homeostasis: Evidence from a birth cohort in Shanghai, China

BACKGROUND

Associations between individual exposure to ozone (O₃) and gestational diabetes mellitus (GDM) have rarely been investigated, and critical windows of O₃ exposure for GDM have not been identified.

OBJECTIVES

We aimed to explore the associations of gestational O₃ exposure with GDM and glucose homeostasis as well as to identify the potential critical windows.

METHODS

A total of 7834 pregnant women were included. Individual O₃ exposure concentrations were evaluated using a high temporal-spatial resolution model. Each participant underwent an oral glucose tolerance test (OGTT) to screen for GDM between 24 and 28 gestational weeks. Multiple logistic and multiple linear regression models were used to estimate the associations of O₃ with GDM risks and with blood glucose levels of OGTT, respectively. Distributed lag nonlinear models (DLNMs) were used to estimate the critical windows of O₃ exposure for GDM.

RESULTS

Nearly 13.29 % of participants developed GDM. After controlling for covariates, we observed increased GDM risks per IQR increment of O₃ exposure in the first trimester (OR = 1.738, 95 % CI: 1.002-3.016) and the first two trimesters (OR = 1.576, 95 % CI: 1.005-2.473). Gestational O₃ exposure was positively associated with increased fasting blood glucose (the first trimester: β = 2.964, 95 % CI: 1.529-4.398; the first two trimesters: β = 1.620, 95 % CI: 0.436-2.804) and 2 h blood glucose (the first trimester: β = 6.569, 95 % CI: 1.775-11.363; the first two trimesters: β = 6.839, 95 % CI: 2.896-10.782). We also observed a concentration-response relationship of gestational O₃ exposure with GDM risk, as well as fasting and 2 h blood glucose levels. Additionally, 5-10 gestational weeks was identified as a critical window of O₃ exposure for GDM development.

CONCLUSION

In summary, we found that gestational O₃ exposure disrupts glucose homeostasis and increases the risk of GDM in pregnant women. Furthermore, 5-10 gestational weeks could be a critical window for the effects of O₃ exposure on GDM.

Habitual coffee consumption and subsequent risk of type 2 diabetes in individuals with a history of gestational diabetes - a prospective study

BACKGROUND

Females with a history of gestational diabetes mellitus (GDM) are at higher risk of developing type 2 diabetes mellitus (T2D) later in life.

OBJECTIVE

This study prospectively examined whether greater habitual coffee consumption was related to a lower risk of T2D among females with a history of GDM.

METHODS

We followed 4522 participants with a history of GDM in the NHS II for incident T2D between 1991 and 2017. Demographic, lifestyle factors including diet, and disease outcomes were updated every 2-4 y. Participants reported consumption of caffeinated and decaffeinated coffee on validated FFQs. Fasting blood samples were collected in 2012-2014 from a subset of participants free of diabetes to measure glucose metabolism biomarkers (HbA1c, insulin, C-peptide; n = 518). We used multivariable Cox regression models to calculate adjusted HRs and 95% CIs for the risk of T2D. We estimated the least squares mean of glucose metabolic biomarkers according to coffee consumption.

RESULTS

A total of 979 participants developed T2D. Caffeinated coffee consumption was inversely associated with the risk of T2D. Adjusted HR (95% CI) for ≤1 (nonzero), 2-3, and 4+ cups/d compared with 0 cup/d (reference) was 0.91 (0.78, 1.06), 0.83 (0.69, 1.01), and 0.46 (0.28, 0.76), respectively (P-trend = 0.004). Replacement of 1 serving/d of sugar-sweetened beverage and artificially sweetened beverage with 1 cup/d of caffeinated coffee was associated with a 17% (risk ratio [RR] = 0.83, 95% CI: 0.75, 0.93) and 9% (RR = 0.91, 95% CI: 0.84, 0.99) lower risk of T2D, respectively. Greater caffeinated coffee consumption was associated with lower fasting insulin and C-peptide concentrations (all P-trend <0.05). Decaffeinated coffee intake was not significantly related to T2D but was inversely associated with C-peptide concentrations (P-trend = 0.003).

CONCLUSIONS

Among predominantly Caucasian females with a history of GDM, greater consumption of caffeinated coffee was associated with a lower risk of T2D and a more favorable metabolic profile.

Hyperglycemia in Pregnancy and Women's Health in the 21st Century

Hyperglycemia is the commonest medical condition affecting pregnancy and its incidence is increasing globally in parallel with the twin epidemics of diabetes and obesity. Both pre-pregnancy diabetes and gestational diabetes are associated with short term pregnancy complications, with the risk of immediate complications generally broadly rising with more severe hyperglycemia. In this article we firstly consider these risks and their optimal management during pregnancy and then broaden our scope to consider the long-term implications of hyperglycemia in pregnancy as it relates to overall maternal and offspring health in a life course perspective.

Work as an Understudied Driver of Racial Inequities in Breastfeeding

Breastfeeding inequities by race are a persistent public health problem in the United States. Inequities in occupation and working conditions likely contribute to relatively less breastfeeding among Black compared to White mothers, yet little research has addressed these interrelationships. Here, we offer a critical review of the literature and a conceptual framework to guide future research about work and racial inequities in breastfeeding. There is a strong public health case for promoting breastfeeding equity for mothers across race groups and occupation types. Existing theory suggests that employment opportunities and working conditions are a likely pathway that connects structural racism to Black-White breastfeeding inequities, in addition to other known factors. We propose a new conceptual model for studying the interrelationships among work, race, and breastfeeding outcomes.

The Fourth Trimester: a Time for Enhancing Transitions in Cardiovascular Care

Purpose of Review

The "fourth trimester" concept, defined as the first 12 weeks after delivery (and beyond), is a critical window of time for clinicians to intervene to optimize women's cardiovascular health after pregnancy. A timely and comprehensive postpartum cardiovascular assessment should be performed in all women following delivery in order to (1) follow up medical conditions present prior to conception, (2) evaluate symptoms and signs of common postpartum complications, and (3) identify risk factors and prevent future adverse cardiovascular outcomes. In this review, we aim to discuss major maternal cardiovascular risk factors such as hypertensive disorders of pregnancy, gestational diabetes mellitus, postpartum weight retention, and postpartum depression, as well as lactation as a potential protective risk modifying factor. Additionally, we will review effectiveness of outpatient interventions to enhance transitions in cardiovascular care during the fourth trimester.

Recent Findings

A seamless hand-off from obstetric to primary care, and potentially cardiology, is needed for early detection and management of hypertension, weight, glycemic control, stress and mood, and long-term cardiovascular risk. Additionally, the use of telemedicine, blood pressure self-monitoring, remote activity monitoring, and behavioral health coaches are potentially feasible modalities to augment clinic-based care for cardiovascular risk factors and weight management, but additional studies are needed to study their long-term effectiveness.

Summary

Development of a comprehensive postpartum care plan with careful consideration of each patient's risk profile and access to resources is critical to improve maternal morbidity and mortality, reduce health disparities, and achieve long-term cardiovascular health for women. Supporting postpartum well-being of women during this transition period requires a multidisciplinary approach, especially primary care engagement, and planning should start before delivery.

Research on the Effect of Nursing Methods for Gestational Diabetes Mellitus Based on Comprehensive Nursing Intervention

In order to explore the effective way of gestational diabetes care, this paper applies comprehensive nursing to gestational diabetes care. In terms of nursing intervention for pregnant women with gestational diabetes mellitus, combining the phased changes of pregnant women's physiological and psychological needs during pregnancy, this paper comprehensively implements health education, diet intervention, exercise intervention, pregnancy monitoring, psychological intervention, infection prevention, and perinatal monitoring and other nursing interventions in a selective and focused manner. This makes the intervention measures at each stage focused, intersecting, interpenetrating, and continuing to play a role, which can effectively improve the implementation effect of the intervention measures and better promote the effective improvement of pregnancy outcomes. In addition, this paper studies the effect of gestational diabetes care based on comprehensive nursing intervention through a controlled trial, and the study verifies that comprehensive nursing has a good effect in gestational diabetes care.

Gestational Diabetes Mellitus Among Asians - A Systematic Review From a Population Health Perspective

Objective

Since Asians are particularly vulnerable to the risk of gestational diabetes mellitus (GDM), the lifecourse health implications of which are far beyond pregnancy, we aimed to summarize the literature to understand the research gaps on current GDM research among Asians.

Methods

We systematically searched the articles in PubMed, Web of Science, Embase, and Scopus by 30 June 2021 with keywords applied on three topics, namely "GDM prevalence in Asians", "GDM and maternal health outcomes in Asians", and "GDM and offspring health outcomes in Asians".

Results

We observed that Asian women (natives and immigrants) are at the highest risk of developing GDM and subsequent progression to type 2 diabetes among all populations. Children born to GDM-complicated pregnancies had a higher risk of macrosomia and congenital anomalies (i.e. heart, kidney and urinary tract) at birth and greater adiposity later in life.

Conclusion

This review summarized various determinants underlying the conversion between GDM and long-term health outcomes in Asian women, and it might shed light on efforts to prevent GDM and improve the lifecourse health in Asians from a public health perspective.

Systematic Review Registration

Prospero, CRD42021286075.

Positive effect of cognitive-behavioral intervention combined with integrated health care on patients with type 2 diabetes

OBJECTIVE

This study was designed to investigate the effects of cognitive-behavioral intervention (CBI) combined with integrated health care (IHC) on glycemic control, adverse mood, health knowledge and self-efficacy in patients with type 2 diabetes mellitus.

METHODS

The clinical data of 115 patients with type 2 diabetes mellitus were retrospectively collected and divided into two groups according to the intervention methods, with 57 patients in group A receiving conventional care and 58 patients in group B receiving CBI combined with IHC. The blood glucose, scores of Hamilton Depression Rating Scale (HAM-D), Hamilton Anxiety Rating Scale (HAM-A), health knowledge, self-efficacy, quality of life, and nursing satisfaction were compared between the two groups before and after intervention.

RESULTS

Compared with group A, group B had lower glycated hemoglobin (HbAlc), 2-h postprandial glucose (2 hPG), and fasting plasma glucose (FPG) levels (P < 0.05), lower HAMD and HAMA scores (P < 0.05), higher health knowledge and self-efficacy scores (P < 0.05), and higher quality of life after intervention (P < 0.05). Group B exhibited a nursing satisfaction rate of 94.83%, higher than that of 70.18% in group A (P < 0.05).

CONCLUSION

The effects of CBI combined with IHC can effectively control blood glucose and improve dysphoria, health knowledge, self-efficacy, and quality of life in patients with type 2 diabetes.

Associations of Metabolic and Obstetric Risk Parameters with Timing of Lactogenesis II

Lactogenesis II is the onset of copious milk production following parturition. Delayed onset of lactogenesis II (DLII) often contributes to poorer lactation performance, which may adversely affect maternal and child health. The present study aims to identify the metabolic and obstetric risk factors for DLII in a secondary analysis of a prospective cohort study following pregnant women through postpartum. We defined the onset of lactogenesis II as delayed if it occurred ≥72 h postpartum. Multiple logistic regression analyses were conducted to evaluate the associations of metabolic and obstetric variables with DLII. Median onset of lactogenesis II was 72.4 h (IQR 60.4–91.6) postpartum, and 55.4% (98 of 177) of women experienced DLII. Time to first breast contact ≥ 2 h postpartum compared to ≤1 h postpartum was associated with DLII (OR 2.71 95% CI 1.12–6.53) with adjustment for age, race, pregravid BMI, primiparity, and mode of delivery, while metabolic variables were not significantly associated with DLII. In this comprehensive examination of potential metabolic and obstetric parameters, earlier timing of putting the infant to the breast remained significantly associated with earlier onset of milk coming in after consideration of the other potential risk factors. Obstetrical practices, including putting the baby to the breast later, may have an important impact on the timing of lactation, and interventions are needed to address this concern.

Cumulative Lactation and Clinical Metabolic Outcomes at Mid-Life among Women with a History of Gestational Diabetes

Lactation is associated with a lower risk of subsequent cardiometabolic disease among parous women; however, the underlying mechanisms are unknown. Further, the potential protective effects of lactation on cardiometabolic risk markers at mid-life among high-risk women with past gestational diabetes (GDM) are not established. Using data from the Diabetes & Women’s Health Study (2012−2014; n = 577), a longitudinal cohort of women with past GDM from the Danish National Birth Cohort (1996−2002), we assessed associations of cumulative lactation duration (none, <6 months, 6−12 months, ≥12−24 months, and ≥24 months) with clinical metabolic outcomes (including type 2 diabetes [T2D], prediabetes, and obesity) and cardiometabolic biomarkers (including biomarkers of glucose/insulin metabolism, fasting lipids, inflammation, and anthropometrics) 9−16 years after enrollment when women were at mid-life. At follow-up, women were 43.9 years old (SD 4.6) with a BMI of 28.7 kg/m2 (IQR 24.6, 33.0); 28.6% of participants had T2D, 39.7% had prediabetes, and 41.2% had obesity. Relative risks (95% CI) of T2D for 0−6, 6−12, 12−24, and ≥24 months of cumulative lactation duration compared to none were 0.94 (0.62,1.44), 0.88 (0.59,1.32), 0.73 (0.46,1.17), and 0.71 (0.40,1.27), respectively. Cumulative lactation duration was not significantly associated with any other clinical outcome or continuous biomarker. In this high-risk cohort of middle-aged women with past GDM, T2D, prediabetes, and obesity were common at follow-up, but not associated with history of cumulative lactation duration 9−16 years after the index pregnancy. Further studies in diverse populations among women at mid-age are needed to understand associations of breastfeeding with T2D.

Lactation Consultation by an International Board Certified Lactation Consultant Improves Breastfeeding Rates for Mothers With Gestational Diabetes Mellitus

BACKGROUND

In patients with gestational diabetes, breastfeeding decreases the lifetime risk of Type 2 diabetes by half. Lactation consultation has been shown to increase breastfeeding rates in the general population but has not been assessed in a gestational diabetes population.

RESEARCH AIMS

To determine if (1) a postpartum International Board Certified Lactation Consultant (IBCLC) consultation during delivery hospitalization improved inclusive (any) or exclusive breastfeeding rates at hospital discharge and 3 months postpartum in participants with GDM; and if (2) obstetrical providers' acknowledgement of maternal feeding preference affected the rates of IBCLC consultation for patients.

METHODS

This was a retrospective, comparative, secondary analysis of a prospective cohort (N = 517) study of women gestational diabetes. Participants who received a IBCLC consultation (n = 386; 74.5%) were compared to those who did not (n = 131; 25.5%). Baseline demographics, antepartum characteristics, neonatal information, mode of infant feeding at hospital discharge and 3 months postpartum, and IBCLC consultation during postpartum hospitalization were measured.

RESULTS

After adjusting for baseline differences, participants who received an IBCLC consultation were more likely to report any breastfeeding at postpartum discharge (aOR 4.87; 95% CI [2.67, 8.86]) and at 3 months postpartum (aOR 5.39; 95% CI [2.61, 11.16]) compared to participants who did not. However, there was no difference in exclusive breastfeeding rates between those who did and did not receive IBCLC consultation.

CONCLUSION

Inpatient IBCLC consultation during the immediate postpartum period was associated with improved rates of any breastfeeding in participants with GDM.

Adiposity, related biomarkers, and type 2 diabetes after gestational diabetes: The Diabetes Prevention Program

OBJECTIVE

This study investigated associations of adiposity and adiposity-related biomarkers with incident type 2 diabetes (T2D) among parous women.

METHODS

Among women in the Diabetes Prevention Program (DPP) who reported a previous live birth, circulating biomarkers (leptin, adiponectin, sex hormone-binding globulin, and alanine aminotransferase; n = 1,711) were measured at enrollment (average: 12 years post partum). Visceral (VAT) and subcutaneous adipose tissue areas at the L2-L3 region and the L3-L4 region were quantified by computed tomography (n = 477). Overall and stratified (by history of gestational diabetes mellitus [GDM]) adjusted Cox proportional hazards models were fit.

RESULTS

Alanine aminotransferase, L2-L3 VAT, and L3-L4 VAT were positively associated (hazard ratio [HR] for 1-SD increases: 1.073, p = 0.024; 1.251, p = 0.009; 1.272, p = 0.004, respectively), and adiponectin concentration was inversely associated with T2D (HR 0.762, p < 0.001). Whereas leptin concentration was not associated with T2D overall, in GDM-stratified models, a 1-SD higher leptin was positively associated with risk of T2D in women without GDM (HR: 1.126, p = 0.016) and inversely in women with a history of GDM (HR: 0.776, p = 0.013, interaction p = 0.002).

CONCLUSIONS

Among parous women, alanine aminotransferase and VAT are positively associated with incident T2D, whereas adiponectin is inversely associated. Leptin is associated with higher risk of T2D in women with a history of GDM but a lower risk in women without a history of GDM.

Interaction of Polygenetic Variants for Gestational Diabetes Mellitus Risk with Breastfeeding and Korean Balanced Diet to Influence Type 2 Diabetes Risk in Later Life in a Large Hospital-Based Cohort

The etiologies of gestational diabetes mellitus (GDM) and type 2 diabetes mellitus (T2DM) are similar. Genetic and environmental factors interact to influence the risk of both types of diabetes. We aimed to determine if the polygenetic risk scores (PRS) for GDM risk interacted with lifestyles to influence type 2 diabetes risk in women aged >40 years in a large hospital-based city cohort. The participants with GDM diagnosis without T2DM before pregnancy were considered the case group (n = 384) and those without GDM and T2DM as the control (n = 33,956) to explore GDM-related genetic variants. The participants with T2DM were the case (n = 2550), and the control (n = 33,956) was the same as GDM genetic analysis for the interaction analysis of GDM genetic risk with lifestyles to influence T2DM risk. The genetic variants for the GDM risk were selected from a genome-wide association study (GWAS), and their PRS from the best model with gene-gene interactions were generated. GDM was positively associated with age at first pregnancy, body mass index (BMI) at age 20, and education level. A previous GDM diagnosis increased the likelihood of elevated fasting serum glucose concentrations and HbA1c contents by 8.42 and 9.23 times in middle-aged and older women. However, it was not associated with the risk of any other metabolic syndrome components. Breast-feeding (≥1 year) was inversely associated with the T2DM risk in later life. In the genetic variant-genetic variant interaction, the best model with 5-SNPs included PTPRD_rs916855529, GPC6_rs9589710, CDKAL1_rs7754840, PRKAG2_rs11975504, and PTPRM_rs80164908. The PRS calculated from the 5-SNP model was positively associated with the GDM risk by 3.259 (2.17-4.89) times after adjusting GDM-related covariates. The GDM experience interacted with PRS for the T2DM risk. Only in non-GDM women PRS was positively associated with T2DM risk by 1.36-times. However, long breastfeeding did not interact with the PRS for T2DM risk. Among dietary patterns, only a Korean-style balanced diet (KBD) showed an interaction with PRS for the T2DM risk. Participants with a low-PRS had the lowest serum glucose concentrations in the high KBD intake but not low KBD intake. In conclusion, participants with a high PRS for GDM risk are positively associated with T2DM risk, and breastfeeding for ≥1 year and consuming KBD offset the PRS for GDM risk to influence T2DM risk in middle-aged and older.

Type 2 diabetes after a pregnancy with gestational diabetes among first nations women in Australia: The PANDORA study

AIMS

To determine among First Nations and Europid pregnant women the cumulative incidence and predictors of postpartum type 2 diabetes and prediabetes and describe postpartum cardiovascular disease (CVD) risk profiles.

METHODS

PANDORA is a prospective longitudinal cohort of women recruited in pregnancy. Ethnic-specific rates of postpartum type 2 diabetes and prediabetes were reported for women with diabetes in pregnancy (DIP), gestational diabetes (GDM) or normoglycaemia in pregnancy over a short follow-up of 2.5 years (n = 325). Pregnancy characteristics and CVD risk profiles according to glycaemic status, and factors associated with postpartum diabetes/prediabetes were examined in First Nations women.

RESULTS

The cumulative incidence of postpartum type 2 diabetes among women with DIP or GDM were higher for First Nations women (48%, 13/27, women with DIP, 13%, 11/82, GDM), compared to Europid women (nil DIP or GDM p < 0.001). Characteristics associated with type 2 diabetes/prediabetes among First Nations women with GDM/DIP included, older age, multiparity, family history of diabetes, higher glucose values, insulin use and body mass index (BMI).

CONCLUSIONS

First Nations women experience a high incidence of postpartum type 2 diabetes after GDM/DIP, highlighting the need for culturally responsive policies at an individual and systems level, to prevent diabetes and its complications.

Analysis and Intervention of Factors Affecting Abnormal Postpartum Glucose Tolerance and Gestational Recurrence in Gestational Diabetes

ObjectiveTo investigate the influencing factors of abnormal postpartum glucose tolerance and pregnancy recurrence in gestational diabetes mellitus (GDM) and to develop reasonable interventions to prevent postpartum glucose tolerance and recurrence of pregnancy. Methods. Retrospective analysis of clinical data of 238 GDM patients during pregnancy, including age, body mass index (BMI) before and after pregnancy, regular exercise during pregnancy, insulin use, family history of diabetes, fasting blood glucose (FPG) during pregnancy, oral glucose tolerance test (OGTT) 2 h time value, blood lipid index, and whether pregnant again. At the same time, the women were followed up by telephone or home visits to understand and guide the patient's diet and exercise. The clinical characteristics of the two groups of patients were compared. According to the OGTT test, the recovery of glucose tolerance in pregnant women 6–8 weeks postpartum was divided into the normal postpartum glucose tolerance group and the abnormal group. Logistic multivariate analysis was used to find the influencing factors of postpartum glucose tolerance and recurrence of pregnancy. Results. Between 238 patients of followed-up, 150 pregnant women had abnormal postpartum glucose tolerance, accounting for 63.03%. There were 115 repregnants, of whom 37 (32.17%) had a recurrence of postpartum glucose tolerance. Pre and postpregnancy BMI, insulin use during pregnancy, family history of diabetes, FPG during pregnancy, OGTT 2 h values, and triglyceride (TG) were independent risk factors for abnormal postpartum diabetes and recurrence of pregnancy in GDM patients. Conclusions. Patients with GDM are at high risk of postpartum abnormal glucose tolerance and pregnancy recurrence, which may be influenced by the pregnant woman's prepregnancy and postpartum BMI, insulin use during pregnancy, family history of diabetes, FPG, OGGT 2 h values during pregnancy, and TG levels. Therefore, health education for pregnant women should be strengthened in the clinic, with guidance on proper diet for weight control, increased exercise, and regular blood glucose screening and monitoring for those at risk.

Association between plasma irisin in pregnancy and postpartum glucose levels among Chinese women: A cohort study

AIMS/INTRODUCTION

The association between plasma irisin and glucose levels in the general population is controversial, and few studies have longitudinally detected this correlation. We aimed to examine whether irisin in pregnancy was associated with postpartum glucose levels among Chinese women and explore the modifiable factors.

MATERIALS AND METHODS

We carried out a prospective cohort study in Guangzhou, China, during 2017 and 2018, and 453 pregnant women (20-28 weeks) were enrolled. Plasma irisin levels in pregnancy were tested. At 6-8 weeks after delivery, 93 women with gestational diabetes mellitus (GDM) underwent a 75-g oral glucose tolerance test, and the other 360 women had a fasting blood glucose (FBG) test. Multivariable linear, quantile and logistic regressions were carried out.

RESULTS

The mean plasma irisin in mid-pregnancy was 13.73 ng/mL. We observed a significantly negative association between mid-pregnancy irisin and postpartum FBG (β: -0.056 ± 0.024). However, quantile regression showed the association was only significant in high percentiles of FBG levels (P50 to P95 ), and the magnitude showed an increasing trend. Higher baseline irisin was also associated with a lower risk of postpartum impaired fasting glucose (relative risk 0.563, 95% confidence interval 0.384-0.825). Furthermore, we found significant interactions between irisin and predominant breast-feeding on FBG and impaired fasting glucose (both Pinteraction  < 0.05). In women with GDM, baseline irisin was non-significantly associated with postpartum postprandial 2-h glucose levels (β: -0.305 ± 0.160, P = 0.061).

CONCLUSIONS

Plasma irisin levels in mid-pregnancy were negatively associated with FBG levels and impaired fasting glucose at 6-8 weeks postpartum among Chinese women, and stronger associations were observed in women with higher FBG values. Furthermore, breast-feeding might modify this relationship.

Association of Habitual Alcohol Consumption With Long-term Risk of Type 2 Diabetes Among Women With a History of Gestational Diabetes

IMPORTANCE

Women with gestational diabetes are at high risk for type 2 diabetes. Identifying modifiable dietary and lifestyle factors, such as alcohol intake, that can be useful in delaying or preventing progression to overt type 2 diabetes is of particular interest.

OBJECTIVE

To evaluate the association between alcohol consumption and risk for type 2 diabetes among women with a history of gestational diabetes.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study included women from the Nurses' Health Study II cohort who reported a history of gestational diabetes and were followed up from January 1, 1991, to December 31, 2017, as part of the Diabetes & Women's Health Study. Data analysis was performed from 2020 to 2021.

EXPOSURES

Dietary intakes, including alcohol, were assessed every 4 years using validated food-frequency questionnaires.

MAIN OUTCOMES AND MEASURES

Multivariable Cox proportional hazards regression models were used to estimate hazard ratios (HRs) and 95% CIs for the association of alcohol intake with risk for incident type 2 diabetes after a pregnancy during which gestational diabetes was diagnosed.

RESULTS

A total of 4740 women were included in the study; the mean (SD) age at baseline was 38.2 (5.0) years, and the median follow-up time was 24 years (interquartile range, 18-28 years), resulting in 78 328 person-years of follow-up. During this period, 897 incident cases of type 2 diabetes were reported. After adjustment for major dietary and lifestyle factors, compared with women who did not consume any alcohol, only alcohol consumption of 5.0 to 14.9 g/d was associated with decreased risk for incident type 2 diabetes (HR, 0.45; 95% CI, 0.33-0.61); there was no association of alcohol consumption of 0.1 to 4.9 g/d or 15.0 g/d or more (maximum, 74.2 g/d) with risk of type 2 diabetes (0.1 to 4.9 g/d: HR, 0.87 [95% CI, 0.73-1.03]; ≥15.0 g/d: HR, 0.62 [95% CI, 0.37-1.04]). After additional adjustment for body mass index, women who reported alcohol consumption of 5.0 to 14.9 g/d had a 41% lower risk for developing incident type 2 diabetes (HR, 0.59; 95% CI, 0.42-0.81); consumption of 0.1 to 4.9 g/d and consumption of 15.0 g/d or more were still not associated with risk of type 2 diabetes, but the results were attenuated (0.1-4.9 g/d: HR, 1.02 [95% CI, 0.85-1.23]; ≥15.0 g/d: HR, 0.75 [95% CI, 0.42-1.33]).

CONCLUSIONS AND RELEVANCE

In this cohort study, among women with a history of gestational diabetes, usual alcohol intake of 5.0 to 14.9 g/d (approximately 0.5-1 drinks per day) was associated with a lower risk for type 2 diabetes. These findings should be interpreted in the context of other known risks and benefits of alcohol consumption when considering clinical recommendations for individual women with a history of gestational diabetes.

Association of lactation with maternal risk of type 2 diabetes: A systematic review and meta-analysis of observational studies

AIM

To investigate the association between lactation and maternal risk of type 2 diabetes, including a potential graded association according to lactation duration.

METHODS

A systematic review and meta-analysis of observational studies that investigated the reported association between lactation (irrespective of duration, intensity or mode) and maternal risk of type 2 diabetes was conducted.

RESULTS

A total of 22 studies (17 cohort studies and five cross-sectional studies) were included in this systematic review, and 16 contributed to the meta-analysis. Studies that investigated the association of lactation with risk of type 2 diabetes in the first months after birth in women with gestational diabetes reported conflicting results. Studies with a longer follow-up showed a graded protective association for lactation and the risk of type 2 diabetes, with a potentially larger risk reduction in women with gestational diabetes than in those without gestational diabetes. Overall, ever versus never lactation was associated with a 27% lower risk of type 2 diabetes (RR 0.73, 95% CI [0.65, 0.83]). Each additional month of lactation was associated with a 1% lower risk of type 2 diabetes (RR 0.99, 95% CI [0.98, 0.99]). However, the overall quality of the studies was modest.

CONCLUSIONS

Lactation is associated with a significantly reduced risk of maternal type 2 diabetes over the life course, particularly in women with gestational diabetes. The protective effect seems to increase with longer duration of lactation. Further research is warranted to understand whether this association is modified by exposure to other risk factors.

Gut dysbiosis during early life: causes, health outcomes, and amelioration via dietary intervention

The colonization and maturation of gut microbiota (GM) is a delicate and precise process, which continues to influence not only infancy and childhood but also adulthood health by affecting immunity. However, many perinatal factors, including gestational age, delivery mode, antibiotic administration, feeding mode, and environmental and maternal factors, can disturb this well-designed process, increasing the morbidity of various gut dysbiosis-related diseases, such as type-1-diabetes, allergies, necrotizing enterocolitis, and obesity. In this review, we discussed the early-life colonization and maturation of the GM, factors influencing this process, and diseases related to the disruption of this process. Moreover, we focused on discussing dietary interventions, including probiotics, oligosaccharides, nutritional supplementation, and exclusive enteral nutrition, in ameliorating early-life dysbiosis and diseases related to it. Furthermore, possible mechanisms, and shortcomings, as well as potential solutions to the drawbacks of dietary interventions, were also discussed.

Interaction between IgA and gut microbiota and its role in controlling metabolic syndrome

Immunoglobulin A (IgA) is the most abundant immunoglobulin isotype secreted into the mucosal tissues, mainly intestinal mucus. Humans can produce several grams of IgA every day, accounting for three quarters of the body's total immunoglobulin content. IgA, together with mucus and antimicrobial peptides, forms the first line of defence for intestinal epithelial cells, protecting them from a significant number of intestinal antigens. IgA also plays a principal role in controlling the gut microbiota (GM), and disruption in IgA can result in dysbiosis, such as the enrichment of Proteobacteria, which are generally bound by IgA. Proteobacteria overexpansion is also usually seen in obesity and colitis. Consistent with this, IgA dysfunction frequently results in metabolic syndrome (MetS), including conditions such as obesity, adiposity, insulin resistance, and inflammation. In contrast, enhanced IgA function can improve, and even prevent, MetS. Interactions among IgA, GM, and metabolism provide a promising avenue to combat MetS.

Barriers and benefits to breastfeeding with gestational diabetes

Gestational diabetes mellitus (GDM) is a disease of glucose intolerance during pregnancy and is associated with infant macrosomia, infant hypoglycemia, and increased risk of type 2 diabetes development for both mother and infant. Although breastfeeding potentially mitigates metabolic sequelae for both mother and her offspring, women with GDM are more likely to introduce formula and, therefore, are less likely to exclusively breastfeed, and some studies show less initiation and shorter breastfeeding duration as well. Therefore, women with GDM and their infants warrant investigation of methods by which to increase breastfeeding exclusivity and duration. Exploration of the barriers to breastfeeding for women with GDM demonstrate not only biologic complications such as maternal obesity, increased prevalence of cesarean section, and infant hypoglycemia, but also maternal report of less provider support of breastfeeding and reduced breastfeeding self-efficacy. Consequently, interventions designed to optimize breastfeeding outcomes in this high-risk population should not only focus on the biology but also on provider behavior and maternal social factors.

Vegetarian diets during pregnancy: effects on the mother's health. A systematic review

While interest in vegetarian nutrition has been steadily increasing, some aspects have not yet been consistently investigated. One topic requiring evidence-based confirmation is the adoption of a vegetarian diet during pregnancy and lactation. Maternal diet is not only correlated with the fetus's and infant's health, but appears relevant for that of the mother as well. Not only is an adequate delivery of nutrients to the fetus and infant mandatory, but the increased physiological needs of the maternal body require an adequate supply of nutrients and can represent harmful stress events that may lead to well-defined pathological conditions. In this review, we aim to systematically investigate state-of-the-art of vegetarian diets during pregnancy and lactation, focusing on maternal nutritional status and pregnancy outcomes. Data are scarce, often inconsistent and not homogeneous for many of the topics we considered, mainly because only a few studies have been performed in developed countries, whereas other studies have derived from developing countries, where vegetarianism can be a proxy indicator of malnutrition. For this reason, we did not find sufficient data to provide evidence-based information and recommendations. To date, the available literature does not clearly support a negative impact on the mother's health and pregnancy outcomes, but, analogously with the findings in the vegetarian adult population, an improvement in the quality of studies might facilitate finding more information on the possible positive impact of well-planned vegetarian diets during pregnancy and lactation. More epidemiological and interventional studies are warranted, in order to address the question as to whether vegetarian nutrition represents an advantage for the mother or poses nutritional issues that need further attention.

Development and characterisation of novel, enzymatically stable oxytocin analogues with beneficial antidiabetic effects in high fat fed mice

BACKGROUND

There is growing evidence to support beneficial effects of the hypothalamic synthesised hormone, oxytocin, on metabolism. However, the biological half-life of oxytocin is short and receptor activation profile unspecific.

METHODS

We have characterised peptide-based oxytocin analogues with structural modifications aimed at improving half-life and receptor specificity. Following extensive in vitro and in vivo characterisation, antidiabetic efficacy of lead peptides was examined in high fat fed (HFF) mice.

RESULTS

Following assessment of stability against enzymatic degradation, insulin secretory activity, receptor activation profile and in vivo bioactivity, analogues 2 N (Ac-C ^˂YIQNC ^>PLG-NH₂) and D7R ((d-C)YIQNCYLG-NH₂) were selected as lead peptides. Twice daily injection of either peptide for 22 days reduced body weight, energy intake, plasma glucose and insulin and pancreatic glucagon content in HFF mice. In addition, both peptides reduced total- and LDL-cholesterol, with concomitant elevations of HDL-cholesterol, and D7R also decreased triglyceride levels. The two oxytocin analogues improved glucose tolerance and insulin responses to intraperitoneal, and particularly oral, glucose challenge on day 22. Both oxytocin analogues enhanced insulin sensitivity, reduced HOMA-IR and increased bone mineral density. In terms of pancreatic islet histology, D7R reversed high fat feeding induced elevations of islet and beta cell areas, which was associated with reductions in beta cell apoptosis. Islet insulin secretory responsiveness was improved by 2 N, and especially D7R, treatment.

CONCLUSION

Novel, enzymatically stable oxytocin analogues exert beneficial antidiabetic effects in HFF mice.

GENERAL SIGNIFICANCE

These observations emphasise the, yet untapped, therapeutic potential of long-acting oxytocin-based agents for obesity and type 2 diabetes.

Adherence to a follow-up program after gestational diabetes

AIM

The aim of this study was to examine attendance for early postpartum follow-up among women with gestational diabetes mellitus (GDM), and to identify factors that influenced their likelihood of attending.

METHODS

One thousand eight hundred and nineteen women with GDM were retrospectively analyzed. During pregnancy, the following data were collected: age, family history of diabetes, ethnicity, prepregnancy BMI, fasting plasma glucose, glycated hemoglobin, gestational week of GDM diagnosis, timing and mode of delivery, newborn's birth weight and length. Glycemia and insulinemia during OGTT, lipid profile and postpartum BMI were assessed at follow-up. Based on the OGTT, women were classified as having normal glucose tolerance (NGT) or abnormal glucose tolerance (AGT), which included impaired fasting glucose (IFG), impaired glucose tolerance (IGT), IFG + IGT, and DM2. Factors predicting postpartum attendance for follow-up and onset of AGT were considered.

RESULTS

Of the 889 (48.9%) who attended the scheduled postpartum OGTT, 741 (83.4%) had NGT, while 148 (16.6%) had AGT (IFG 6.7%, IGT 7.7%, IFG + IGT 0.8%, DM2 1.5%). The predictors of adherence to follow-up were: not belonging to an immigrant group; family history of DM2; and insulin therapy in pregnancy. The same factors were also predictive of AGT. Our data suggest a role of ethnicity in both attendance for postpartum follow-up and its outcome.

CONCLUSION

Despite efforts to provide care for women with GDM, postpartum screening rates are still low among Italian women, and especially among immigrants. Hence, the need to improve these patients' awareness of the severe risk of developing diabetes after pregnancy, concentrating efforts especially on women belonging to the most at risk ethnic groups.

Improving Breastfeeding by Empowering Mothers in Vietnam: A Randomised Controlled Trial of a Mobile App

Breastfeeding provides benefits to the infant and mother; however, the rates of breastfeeding, particularly exclusive breastfeeding, remain below optimal levels in many Asian countries. The aim of this study is to review the benefits of breastfeeding to mothers and infants and current rates of breastfeeding in Vietnam, and to evaluate the effectiveness of a mobile application on exclusive breastfeeding among mothers in Vietnam. A two-arm, parallel triple-blinded randomised controlled trial will be conducted among 1000 mothers in Hanoi City, Vietnam, during 2020-2021. Eligible participants are pregnant women who will seek antenatal care from health facilities at 24-36 weeks of gestation and plan to deliver at two participating hospitals, own a smartphone, and carry a singleton foetus. Permuted-block randomisation method stratified by maternal age, education and parity will be used to ensure an equal number of participants in each group. A smartphone app will be developed to deliver breastfeeding and non-breastfeeding information to the intervention and control group, respectively. Data will be collected at baseline, before hospital discharge, and at 1, 4, and 6 months postpartum. This study envisages demonstrating whether a smartphone-based intervention can be effective at improving breastfeeding in Vietnam. Trials registration: ACTRN12619000531112.

Predictors and consequences of weight retention in the early and late postpartum period in women with gestational diabetes

AIMS

To assist preventive strategies, we investigated the predictors and consequences of postpartum weight retention (PPWR) in the early and late postpartum period in women with gestational diabetes (GDM).

METHODS

862 women with GDM between 2011 and 2019 were prospectively included. We investigated PPWR at 6-8 weeks (n = 862) and at 1-year (n = 259) postpartum. Potential predictors included gestational weight gain (GWG), weight, BMI, and glucose control parameters during and after pregnancy.

RESULTS

Mean PPWR at 6-8 weeks and 1-year postpartum were 4.6 ± 5.7 kg and 4.0 ± 7.4 kg. The proportion of women with PPWR at 6-8 weeks and at 1-year postpartum were 81% and 66.4% respectively. At 6-8 weeks postpartum, women with PPWR had higher pre-pregnancy weight, 7.5 ± 0.2 kg higher GWG and higher postpartum weight (all p ≤ 0.02), without presenting metabolic differences. At 1-year postpartum, there were no differences in anthropometric parameters before and during pregnancy between women with or without PPWR, except for a 4 ± 0.4 kg higher GWG (p < 0.001). However, women with PPWR had increased postpartum weight and BMI, higher fasting glucose and more pronounced increase in Δfasting glucose and ΔHbA1c at 1-year postpartum (all p ≤ 0.03). GWG predicted higher PPWR at both 6-8 weeks and at 1-year postpartum (all p < 0.001).

CONCLUSION

Women with PPWR had increased anthropometric parameters and adverse metabolic consequences at 1-year postpartum. GWG was the most relevant predictor of PPWR.