Racial differences of incident diabetes postpartum in women with a history of gestational diabetes

Gestational Diabetes Mellitus and Subsequent Risks of Diabetes and Cardiovascular Diseases: the Life Course Perspective and Implications of Racial Disparities

PURPOSE OF REVIEW

Gestational diabetes mellitus (GDM) is one of the most common pregnancy complications worldwide and the prevalence is continuously rising globally. Importantly, GDM is not an isolated complication of pregnancy. Growing evidence suggests that individuals with GDM, compared to those without GDM, have an increased risk of subsequent type 2 diabetes (T2D) and cardiovascular diseases (CVD). Substantial racial and ethnic disparities exist in the risk of GDM. However, the role of race and ethnicity in the progression from GDM to T2D and CVD remains unclear. The purpose of the current review is to summarize recent research about GDM and its life-course impacts on cardiometabolic health, including 1) the peak time of developing T2D and CVD risks after GDM, 2) the racial and ethnic disparities in the risk cardiometabolic diseases after GDM, 3) the biological plausibility and underlying mechanisms, and 4) recommendations for screening and prevention of cardiometabolic diseases among individuals with GDM, collectively to provide an updated review to guide future research.

RECENT FINDINGS

Growing evidence has indicated that individuals with GDM had greater risks of T2D (7.4 to 9.6 times), hypertension (78% higher), and CDV events (74% higher) after GDM than their non-GDM counterparts. More recently, a few studies also suggested that GDM could slightly increase the risk of mortality. Available evidence suggests that key CVD risk factors such as blood pressure, plasma glucose, and lipids levels are all elevated as early as < 1 year postpartum in individuals with GDM. The risk of T2D and hypertension is likely to reach a peak between 3-6 years after the index pregnancy with GDM compared to normal glycemia pregnancy. Cumulative evidence also suggests that the risk of cardiometabolic diseases including T2D, hypertension, and CVD events after GDM varies by race and ethnicity. However, whether the risk is higher in certain racial and ethnic groups and whether the pattern may vary by the postpartum cardiometabolic outcome of interest remain unclear. The underlying mechanisms linking GDM and subsequent T2D and CVD are complex, often involving multiple pathways and their interactions, with the specific mechanisms varying by individuals of different racial and ethnic backgrounds. Diabetes and CVD risk screening among individuals with GDM should be initiated early during postpartum and continue, if possible, frequently. Unfortunately, adherence to postpartum glucose testing with either obstetrician or primary care providers remained poor among individuals with GDM. A life-course perspective may provide critical information to address clinical and public health gaps in postpartum screening and interventions for preventing T2D and CVD risks in individuals with GDM. Future research investigating the racial- and ethnic-specific risk of progression from GDM to cardiometabolic diseases and the role of multi-domain factors including lifestyle, biological, and socio-contextual factors are warranted to inform tailored and culture-appropriate interventions for high-risk subpopulations. Further, examining the barriers to postpartum glucose testing among individuals with GDM is crucial for the effective prevention of cardiometabolic diseases and for enhancing life-long health.

Preconception HbA1c Levels in Adolescents and Young Adults and Adverse Birth Outcomes

Importance

Subclinical hyperglycemia before pregnancy may be associated with the likelihood of maternal morbidity but is understudied among young people.

Objective

To explore the association of preconception hemoglobin A1c (HbA1c) levels among adolescents and young adults with risk of gestational diabetes at first live birth.

Design, Setting, and Participants

This retrospective cohort study used linked 2009 to 2017 birth registry, hospital discharge, and New York City Department of Health A1C Registry data for birthing individuals aged 10 to 24 years with no history of diabetes and at least 1 preconception HbA1c test in New York, New York. Statistical analysis was performed from August to November 2022.

Exposure

Preconception HbA1c values categorized as no diabetes (HbA1c <5.7%) or prediabetes (HbA1c ≥5.7% to <6.5%).

Main Outcomes and Measures

The primary outcome was gestational diabetes at first birth. Secondary outcomes included hypertensive disorders of pregnancy, preterm birth, cesarean delivery, and macrosomia. Log binomial regression was used to estimate the relative risk (RR) of gestational diabetes at first birth by preconception HbA1c level, adjusting for prepregnancy characteristics. The optimal HbA1c threshold for gestational diabetes was examined using receiver operating curve regression.

Results

A total of 14 302 individuals (mean [SD] age, 22.10 [1.55] years) met study eligibility criteria. Of these, 5896 (41.0%) were Hispanic, 4149 (29.0%) were Black, 2583 (18.1%) were White, 1516 (10.6%) were Asian, and 185 (1.3%) had other or unknown race and ethnicity. Most (11 407 individuals [79.7%]) had normoglycemia before pregnancy, and 2895 individuals (20.2%) had prediabetes. Adjusting for prepregnancy characteristics, those with preconception prediabetes had more than twice the risk of gestational diabetes vs those with normoglycemia (adjusted RR [aRR], 2.21; 95% CI, 1.91-2.56). Preconception prediabetes was associated with small increases in the likelihood of a hypertensive disorder of pregnancy (aRR, 1.18; 95% CI, 1.03-1.35) and preterm delivery (aRR, 1.18; 95% CI, 1.02-1.37). The aRRs for cesarean delivery (aRR, 1.09; 95% CI, 0.99-1.20) and macrosomia (aRR, 1.13; 95% CI, 0.93-1.37) were increased but not statistically significant. The optimal HbA1c threshold to identify gestational diabetes among adolescents and young adults was 5.6%. The threshold did not vary by obesity status but was slightly lower among Hispanic individuals (HbA1c of 5.5%).

Conclusions and Relevance

In this study of adolescents and young adults with at least 1 preconception HbA1c test, prediabetes was associated with increased likelihood of maternal cardiometabolic morbidity at first birth. Efforts to optimize cardiometabolic health before pregnancy may avert excess maternal risk.

Advances in the study of the correlation between insulin resistance and infertility

This is a narrative review of the progress of research on the correlation between insulin resistance and infertility. Insulin resistance (IR) is not only involved in the development of various metabolic diseases, but also affects female reproductive function, and to some extent is closely related to female infertility. IR may increase the risk of female infertility by activating oxidative stress, interfering with energy metabolism, affecting oocyte development, embryo quality and endometrial tolerance, affecting hormone secretion and embryo implantation, as well as affecting assisted conception outcomes in infertile populations and reducing the success rate of assisted reproductive technology treatment in infertile populations. In addition, IR is closely associated with spontaneous abortion, gestational diabetes and other adverse pregnancies, and if not corrected in time, may increase the risk of obesity and metabolic diseases in the offspring in the long term. This article provides a review of the relationship between IR and infertility to provide new ideas for the treatment of infertility.

Influence of Gestational Diabetes Mellitus on Diabetes Risk and Glycemic Control in a Retrospective Population-Based Cohort

OBJECTIVE

Racial/ethnic-specific estimates of the influence of gestational diabetes mellitus (GDM) on type 2 diabetes remain underexplored in large population-based cohorts. We estimated racial/ethnic differences in the influence of GDM on diabetes risk and glycemic control in a multiethnic, population-based cohort of postpartum women.

RESEARCH DESIGN AND METHODS

Hospital discharge and vital registry data for New York City (NYC) births between 2009 and 2011 were linked with NYC A1C Registry data between 2009 and 2017. Women with baseline diabetes (n = 2,810) were excluded for a final birth cohort of 336,276. GDM on time to diabetes onset (two A1C tests of ≥6.5% from 12 weeks postpartum onward) or glucose control (first test of A1C <7.0% following diagnosis) was assessed using Cox regression with a time-varying exposure. Models were adjusted for sociodemographic and clinical factors and stratified by race/ethnicity.

RESULTS

The cumulative incidence for diabetes was 11.8% and 0.6% among women with and without GDM, respectively. The adjusted hazard ratio (aHR) of GDM status on diabetes risk was 11.5 (95% CI 10.8, 12.3) overall, with slight differences by race/ethnicity. GDM was associated with a lower likelihood of glycemic control (aHR 0.85; 95% CI 0.79, 0.92), with the largest negative influence among Black (aHR 0.77; 95% CI 0.68, 0.88) and Hispanic (aHR 0.84; 95% CI 0.74, 0.95) women. Adjustment for screening bias and loss to follow-up modestly attenuated racial/ethnic differences in diabetes risk but had little influence on glycemic control.

CONCLUSIONS

Understanding racial/ethnic differences in the influence of GDM on diabetes progression is critical to disrupt life course cardiometabolic disparities.

Women's Reproductive Milestones and Cardiovascular Disease Risk: A Review of Reports and Opportunities From the CARDIA Study

In 1985 to 1986, the CARDIA (Coronary Artery Risk Development in Young Adults) study enrolled 5115 Black or White participants, including 2788 women, aged 18 to 30 years. Over the following 35 years, the CARDIA study amassed extensive longitudinal data on women's reproductive milestones, spanning menarche to menopause. Although not initially conceived as a study of women's health, >75 CARDIA study publications address relationships between reproductive factors and events with cardiovascular and metabolic risk factors, subclinical and clinical cardiovascular disease, and social determinants of health. The CARDIA study was one of the earliest population-based reports to note Black-White differences in age at menarche and associations with cardiovascular risk factors. Adverse pregnancy outcomes, particularly gestational diabetes and preterm birth, have been assessed along with postpartum behaviors, such as lactation. Existing studies have examined risk factors for adverse pregnancy outcomes and lactation, as well as their relationship to future cardiovascular and metabolic risk factors, diagnoses, and subclinical atherosclerosis. Ancillary studies examining components of polycystic ovary syndrome and ovarian biomarkers, such as anti-Müllerian hormone, have facilitated examination of reproductive health in a population-based cohort of young adult women. As the cohort transitioned through menopause, examination of the importance of premenopausal cardiovascular risk factors along with menopause has improved our understanding of shared mechanisms. The cohort is now aged in the 50s to mid-60s, and women will begin to experience a greater number of cardiovascular events as well as other conditions, such as cognitive impairment. Thus, in the next decade, the CARDIA study will provide a unique resource for understanding how the women's reproductive life course epidemiology informs cardiovascular risk, as well as reproductive and chronological aging.

The Impact of Ethnicity on Fetal and Maternal Outcomes of Gestational Diabetes

Background and Objectives: The prevalence of gestational diabetes mellitus (GDM) significantly varies across different ethnic groups. In particular, Africans, Latinos, Asians and Pacific Islanders are the ethnic groups with the highest risk of GDM. The aim of this study was to evaluate the impact of ethnicity on pregnancy outcomes in GDM. Patients and Methods: n = 399 patients with GDM were enrolled, n = 76 patients of high-risk ethnicity (HR-GDM), and n = 323 of low-risk ethnicity (LR-GDM). Clinical and biochemical parameters were collected during pregnancy until delivery. Fetal and maternal short-term outcomes were evaluated. Results: HR-GDM had significantly higher values of glycosylated hemoglobin checked at 26−29 weeks of gestation (p < 0.001). Gestational age at delivery was significantly lower in HR-GDM (p = 0.03). The prevalence of impaired fetal growth was significantly higher in HR-GDM than LR-GDM (p = 0.009). In logistic regression analysis, the likelihood of impaired fetal growth was seven times higher in HR-GDM than in LR-GDM, after adjustment for pre-pregnancy BMI and gestational weight gain (OR = 7.1 [2.0−25.7] 95% CI, p = 0.003). Conclusions: HR-GDM had worse pregnancy outcomes compared with LR-GDM. An ethnicity-tailored clinical approach might be effective in reducing adverse outcomes in GDM.

Lifestyle behaviors and cardiovascular risk profiles among parous women by gestational diabetes status, 2007-2018

BACKGROUND AND AIMS

Women with prior gestational diabetes mellitus (GDM) are at elevated risk of type 2 diabetes mellitus and cardiovascular disease. We compared cardiometabolic risk factors among parous U.S. women ages 20-44 by history of GDM.

METHODS AND RESULTS

Using data from the National Health and Nutrition Examination Survey (NHANES) from 2007 to 2018, 3537 parous women were classified by self-reported GDM history. We compared anthropometric measures, glycemia, blood pressure, lipids, lifestyle factors, cardiovascular health, and cardiometabolic disease prevalence by GDM status. NHANES survey design was taken into account. Women without history of GDM were younger and, after adjusting for age, race/ethnicity, and education, had more favorable cardiometabolic risk factor profiles for measures of anthropometry, glycemia, diabetes, many lipids, physical activity, diet, and overall cardiovascular health than women with history of GDM. Many patterns persisted after further adjustment for lifestyle factors. In analyses stratified by race/ethnicity, many patterns persisted, though there were key differences. Hypertension prevalence differed by GDM history only among Hispanic women. In women of other race/ethnicity, there was no difference in healthy eating or body mass index by GDM history. In non-Hispanic Black women, there was no difference in healthy eating by GDM history.

CONCLUSION

Among parous U.S. women ages 20-44, those with history of GDM had less favorable cardiometabolic risk factor profiles than those without history of GDM. This highlights the importance of continued efforts to develop and test multilevel interventions to improve cardiometabolic risk factors among reproductive-age women with a history of GDM.