The use of longitudinal hemoglobin A1c values to predict adverse obstetric and neonatal outcomes in pregnancies complicated by pregestational diabetes

Associations of serum D-dimer and glycosylated hemoglobin levels with third-trimester fetal growth restriction in gestational diabetes mellitus

BACKGROUND

Gestational diabetes mellitus (GDM) is a special type of diabetes that commonly occurs in women during pregnancy and involves impaired glucose tolerance and abnormal glucose metabolism; GDM is diagnosed for the first time during pregnancy and can affect fetal growth and development.

AIM

To investigate the associations of serum D-dimer (D-D) and glycosylated hemoglobin (HbA1c) levels with third-trimester fetal growth restriction (FGR) in GDM patients.

METHODS

The clinical data of 164 pregnant women who were diagnosed with GDM and delivered at the Obstetrics and Gynecology Hospital of Fudan University from January 2021 to January 2023 were analyzed retrospectively. Among these women, 63 whose fetuses had FGR were included in the FGR group, and 101 women whose fetuses had normal body weights were included in the normal body weight group (normal group). Fasting venous blood samples were collected from the elbow at 28-30 wk gestation and 1-3 d before delivery to measure serum D-D and HbA1c levels for comparative analysis. The diagnostic value of serum D-D and HbA1c levels for FGR was evaluated by receiver operating characteristic analysis, and the influencing factors of third-trimester FGR in GDM patients were analyzed by logistic regression.

RESULTS

Serum fasting blood glucose, fasting insulin, D-D and HbA1c levels were significantly greater in the FGR group than in the normal group, while the homeostasis model assessment of insulin resistance values were lower (P < 0.05). Regarding the diagnosis of FGR based on serum D-D and HbA1c levels, the areas under the curves (AUCs) were 0.826 and 0.848, the cutoff values were 3.04 mg/L and 5.80%, the sensitivities were 81.0% and 79.4%, and the specificities were 88.1% and 87.1%, respectively. The AUC of serum D-D plus HbA1c levels for diagnosing FGR was 0.928, and the sensitivity and specificity were 84.1% and 91.1%, respectively. High D-D and HbA1c levels were risk factors for third-trimester FGR in GDM patients (P < 0.05).

CONCLUSION

D-D and HbA1c levels can indicate the occurrence of FGR in GDM patients in the third trimester of pregnancy to some extent, and their combination can be used as an important index for the early prediction of FGR.

Development and internal validation of a clinical score to predict neonatal hypoglycaemia in women with gestational diabetes

INTRODUCTION

Gestational diabetes (GD) is a risk factor for neonatal hypoglycaemia (NH), but other factors can increase this risk.

OBJECTIVES

To create a score to predict NH in women with GD.

METHODS

Retrospective study of women with GD with a live singleton birth between 2012 and 2017 from the Portuguese GD registry. Pregnancies with and without NH were compared. A logistic regression was used to study NH predictors. Variables independently associated with NH were used to score derivation. The model's internal validation was performed by a bootstrapping. The association between the score and NH was assessed by logistic regression.

RESULTS

We studied 10216 pregnancies, 410 (4.0%) with NH. The model's AUC was 0.628 (95%CI: 0.599-0.657). Optimism-corrected c-index: 0.626. Points were assigned to variables associated with NH in proportion to the model's lowest regression coefficient: insulin-treatment 1, preeclampsia 3, preterm delivery 2, male sex 1, and small-for-gestational-age 2, or large-for-gestational-age 3. NH prevalence by score category 0-1, 2, 3, 4, and ≥5 was 2.3%, 3.0%, 4.5%, 6.0%, 7.4%, and 11.5%, respectively. Per point, the OR for NH was 1.35 (95% CI: 1.27-1.42). A score of 2, 3, 4, 5 or ≥6 (versus ≤1) had a OR for NH of 1.67 (1.29-2.15), 2.24 (1.65-3.04), 2.83 (2.02-3.98), 3.08 (1.83-5.16), and 6.84 (4.34-10.77), respectively.

CONCLUSION

Per each score point, women with GD had 35% higher risk of NH. Those with ≥6 points had 6.8-fold higher risk of NH compared to a score ≤1. Our score may be useful for identifying women at a higher risk of NH.

Implementing point-of-care hemoglobin A1C testing in an obstetrics outpatient clinic

BACKGROUND

A1C ≥6.0% is associated with increased risk of adverse outcomes in pregnant diabetic patients. A1C testing is recommended by the American Diabetes Association as a secondary measure of glycemic control in pregnant patients.

OBJECTIVE

To determine the utility of A1C point-of-care testing (POCT) during pregnancy to facilitate rapid counseling and diabetes care, particularly in relatively low-income transient patient populations.

METHODS

We performed a single-center, retrospective analysis of patients presenting to an outpatient obstetrics office with routine, in-laboratory A1C testing, before and after the implementation of POCT for A1C (n = 70 and n = 75, respectively). Demographics, results, physician referral to a nutritionist, counseling, and outcomes were retrieved from patient electronic medical records.

RESULTS

In total, 9% and 23% of the in-laboratory and POCT groups, respectively, were referred for nutrition services (P = .02). Of these, 22% of the in-laboratory group and 42% of the POCT group received immediate counseling (P < .01). An inverse correlation was observed between A1C level at study entry and gestational weeks at delivery, with a Pearson r value of -0.39 (-0.58 to -0.16) for the in-laboratory group and -0.38 (-0.57 to -0.14) for the POCT group. No statistically significant difference in pregnancy outcomes was observed.

CONCLUSION

Implementation of A1C POCT was associated with immediate counseling and management of the health of pregnant patients, but was not associated with improved outcomes, in a low-resource patient population.

An Evidence-Based Framework for Creating Inclusive and Personalized mHealth Solutions-Designing a Solution for Medicaid-Eligible Pregnant Individuals With Uncontrolled Type 2 Diabetes

Mobile health (mHealth) apps can be an evidence-based approach to improve health behavior and outcomes. Prior literature has highlighted the need for more research on mHealth personalization, including in diabetes and pregnancy. Critical gaps exist on the impact of personalization of mHealth apps on patient engagement, and in turn, health behaviors and outcomes. Evidence regarding how personalization, engagement, and health outcomes could be aligned when designing mHealth for underserved populations is much needed, given the historical oversights with mHealth design in these populations. This viewpoint is motivated by our experience from designing a personalized mHealth solution focused on Medicaid-enrolled pregnant individuals with uncontrolled type 2 diabetes, many of whom also experience a high burden of social needs. We describe fundamental components of designing mHealth solutions that are both inclusive and personalized, forming the basis of an evidence-based framework for future mHealth design in other disease states with similar contexts.

Association between glycemic control and group B streptococcus colonization among pregnant individuals with pregestational diabetes

PROBLEM

Pregestational diabetes increases the risk of group B streptococcus (GBS) colonization in pregnancy. Whether glycemic control is associated with differences in this risk is unknown. We examined the association between glycemic control and GBS colonization among pregnant individuals with pregestational diabetes.

METHOD OF STUDY

A retrospective cohort of pregnant individuals with pregestational diabetes at a tertiary care center. The exposure was glycemic control, measured as hemoglobin A1c (A1c) at >20 weeks and assessed categorically at thresholds of <6.5% and <6.0%, and secondarily, as a continuous percentage. The outcome was maternal GBS colonization. Multivariable logistic regression was used and adjusted for age, parity, race, and ethnicity as a social determinant, body mass index, type of diabetes, and gestational age at A1c assessment.

RESULTS

Among 305 individuals (33% Type 1, 67% type 2), 45.0% (n = 140) were colonized with GBS. Individuals with an A1c < 6.5% were half as likely to be colonized with GBS compared with those with a A1c ≥ 6.5% (38.8% vs. 53.9%; adjusted odds ratio, AOR: 0.55; 95% CI: 0.33-0.91). Results were unchanged at an A1c threshold of <6.0% (35.7% vs. 48.5%; AOR: 0.60; 95% CI: 0.36-0.98). Individuals with a higher A1c as a continuous measure (%) were more likely to be colonized (AOR: 1.57 per 1%; 95% CI: 1.25-1.97).

CONCLUSIONS

Pregnant individuals with pregestational diabetes with worse glycemic control were at an increased risk of GBS colonization. Further study is needed to understand if improved glycemic control leads to lower risk of GBS colonization.

Neonatal outcomes and rationale for timing of birth in perinatal diabetes: a retrospective cohort study

BACKGROUND

The American College of Obstetricians and Gynecologists recommends delivery in the 39th week of pregnancy for patients with pregestational and medication-controlled gestational diabetes with consideration for earlier delivery among those with poor glucose control.

OBJECTIVE

We sought to evaluate the impact of birth before 39 weeks' gestation exclusively for diabetes-related indications on neonatal outcomes and clinician rationale for these recommendations.

STUDY DESIGN

This was a retrospective cohort study of all singleton, nonanomalous pregnancies complicated by diabetes. Patients were identified through an obstetrical database containing information of 90,185 births from 2011 to 2021. Patients who delivered in a given week of gestation exclusively for diabetes-related indications were compared with ongoing pregnancies. Recommended births for other obstetrical indications were excluded from the diabetes-related indications cohorts. The primary outcome was neonatal intensive care unit admission. Secondary outcomes included neonatal intensive care unit length of stay, stillbirth, neonatal death, hypoglycemia, respiratory distress syndrome, and shoulder dystocia. For all births before 39 weeks' gestation, the electronic medical records were reviewed to confirm the rationale for the intervention for a diabetes-indicated condition.

RESULTS

From the 90,185 recorded births that occurred in 2011 to 2021, 4750 patients with diabetes were identified. Of those, 30.5% (n=1449) had a recommended birth for a diabetes-related indications with 2.2% of those (n=32) occurring at 36 weeks' gestation, 7.9% (n=114) at 37 weeks' gestation, 9.7% (n=141) at 38 weeks' gestation, and 63.0% (n=913) at 39 weeks' gestation. Births that occurred at 36 and 37 weeks' gestation exclusively for diabetes-related indications had higher rates of neonatal intensive care unit admission than the respective ongoing pregnancies (62.5% vs 8.7%; P<.001 and 25.4% vs 7.2%; P<.001). There was no difference in neonatal intensive care unit admission for births at 38 or 39 weeks' gestation when compared with ongoing pregnancy. For neonates born at 36 and 37 weeks' gestation in comparison with ongoing pregnancies, the median neonatal intensive care unit length of stay was 11.0 vs 2.8 days, (P<.001) and 4.4 vs 2.6 days (P=.026), respectively. There were significantly increased rates of neonatal hypoglycemia and respiratory distress syndrome among births that occurred at 36, 37, and 38 weeks' gestation when compared with ongoing pregnancies. There were no differences in the rate of stillbirth in this cohort. Primary factors cited for early birth were poor glycemic control (71.4%), recommendation by a maternal-fetal medicine specialist (38.7%), and suspected fetal macrosomia (27.9%). Overall, 46.7%, 32.8%, and 20.6% of patients had 1, 2, or ≥3 indications, respectively, listed as rationale for early birth. Overall, few objective measures were used to recommend birth before 39 weeks' gestation owing to diabetes.

CONCLUSION

In pregnancies complicated by diabetes, early birth exclusively for diabetes-related indications was associated with increased neonatal intensive care unit admission and length of stay and with neonatal morbidity. Little objective data are documented by clinicians to support their recommendations for early birth associated with diabetes. Additional clinical guidelines are needed to define suboptimal glucose control necessitating birth before 39 weeks' gestation.

Diabetes and pregnancy study (DAPSY): a 10-year single-center cohort study of pregnancies affected by diabetes

PURPOSE

The aim of our study was to investigate to what degree clinical characteristics can contribute to incidence and structure of pregnancy and childbirth complications in women with diabetes, and to reveal key risk factors for adverse outcomes.

METHODS

We conducted a retrospective single-center cohort study from January 2008 through December 2017, including 3069 singleton pregnancies, affected by type 1 diabetes (T1D, n = 498), type 2 diabetes (T2D, n = 214), and gestational diabetes mellitus (GDM, n = 2357).

RESULTS

More than 10 years duration of T1D associated with increased risk for preterm birth (RR 2.03, 95% CI 1.28-3.20) and preeclampsia (RR 1.57, 95% CI 1.09-2.26). Diabetic nephropathy, same as diabetic proliferative retinopathy, was associated with increased risk of C-section, preeclampsia development, SGA delivery. In patients with T1D who received CSII (12%), we do not report superior outcomes compared to MDI. Pre-pregnancy HbA1c level less than 6.5% reduced the risk of preeclampsia for T1D (RR 0.28, 95% CI 0.19-0.67) and risk of LGA birth for T2D (RR 0.43, 95% CI 0.19-0.92). Achieving glycemic target values by full-term pregnancy reduced the risk of excessive fetal adiposity (RR 0.81 for T1D, RR 0.39 for T2D). For T2D and GDM, the leading risk factors were obesity and chronic hypertension. For patients with GDM, insulin administration and early diagnosis of GDM were the significant risk factors for adverse outcomes.

CONCLUSION

Diabetes during pregnancy is challenging for the clinician, but optimizing glycemic control, treatment regimens, and close attention to comorbidities can help to reduce the risks and ensure appropriate quality diabetes management.

Call for a More Specific Diagnosis of Infant of a Diabetic Mother to Optimize Neonatal Care

Hyperglycemia is the diagnostic feature of diabetes mellitus (DM), and during pregnancy, hyperglycemia has numerous serious implications for organogenesis and fetal growth. Each type of DM has different neonatal implications based on pathogenesis, length of disease, and comorbidities. Currently, limited attention is given to the woman's type of DM when evaluating risks for neonates. The diagnosis of infant of a diabetic mother is not sufficient because of the varying pathophysiology of diabetes classifications and associated neonatal outcomes. By expanding the diagnosis to include the woman's classification and glucose control, maternity and neonatal care providers could develop plans of care based on potential neonatal outcomes, including anticipatory guidance for families. In this commentary, we propose a more specific diagnosis, rather than infant of a diabetic mother, to better serve these infants.

The effect of maternal pregestational diabetes on fetal autonomic nervous system

Heart rate variability assessment of neonates of pregestational diabetic mothers have shown alterations in the autonomic nervous system (ANS). The objective was to study the effect of maternal pregestational diabetes on ANS at the fetal stage by combining cardiac and movement parameters using a non-invasive fetal magnetocardiography (fMCG) technique. This is an observational study with 40 participants where fetuses from a group of 9 Type 1, 19 Type 2 diabetic, and 12 non-diabetic pregnant women were included. Time and frequency domain fetal heart rate variability (fHRV) and coupling of movement and heart rate acceleration parameters related to fetal ANS were analyzed. Group differences were investigated using analysis of covariance to adjust for gestational age (GA). When compared to non-diabetics, the Type 1 diabetics had a 65% increase in average ratio of very low-frequency (VLF) to low-frequency (LF) bands and 63% average decrease in coupling index after adjusting for GA. Comparing Type 2 diabetics to non-diabetics, there was an average decrease in the VLF (50%) and LF bands (63%). Diabetics with poor glycemic control had a higher average VLF/LF (49%) than diabetics with good glycemic control. No significant changes at p < 0.05 were observed in high-frequency (HF) frequency domain parameters or their ratios, or in the time domain. Fetuses of pregestational diabetic mothers exhibited some differences in fHRV frequency domain and heart rate-movement coupling when compared to non-diabetics but the effect of fHRV related to fetal ANS and sympathovagal balance were not as conclusive as observed in the neonates of pregestational diabetic mothers.

Association of community walkability and glycemic control among pregnant individuals with pregestational diabetes mellitus

BACKGROUND

Neighborhood walkability is a community-level social determinant of health that measures whether people who live in a neighborhood walk as a mode of transportation. Whether neighborhood walkability is associated with glycemic control among pregnant individuals with pregestational diabetes remains to be defined.

OBJECTIVE

This study aimed to evaluate the association between community-level neighborhood walkability and glycemic control as measured by hemoglobin A1c (A1C) among pregnant individuals with pregestational diabetes.

STUDY DESIGN

This was a retrospective analysis of pregnant individuals with pregestational diabetes enrolled in an integrated prenatal and diabetes care program from 2012 to 2016. Participant addresses were geocoded and linked at the census-tract level. The exposure was community walkability, defined by the US Environmental Protection Agency National Walkability Index (score range 1-20), which incorporates intersection density (design), proximity to transit stops (distance), and a mix of employment and household types (diversity). Individuals from neighborhoods that were the most walkable (score, 15.26-20.0) were compared with those from neighborhoods that were less walkable (score <15.26), as defined per national Environmental Protection Agency recommendations. The outcomes were glycemic control, including A1C <6.0% and <6.5%, measured both in early and late pregnancy, and mean change in A1C across pregnancy. Modified Poisson regression and linear regression were used, respectively, and adjusted for maternal age, body mass index at delivery, parity, race and ethnicity as a social determinant of health, insurance status, baseline A1C, gestational age at A1C measurement in early and late pregnancy, and diabetes type.

RESULTS

Among 417 pregnant individuals (33% type 1, 67% type 2 diabetes mellitus), 10% were living in the most walkable communities. All 417 individuals underwent A1C assessment in early pregnancy (median gestational age, 9.7 weeks; interquartile range, 7.4-14.1), and 376 underwent another A1C assessment in late pregnancy (median gestational age, 30.4 weeks; interquartile range, 27.8-33.6). Pregnant individuals living in the most walkable communities were more likely to have an A1C <6.0% in early pregnancy (15% vs 8%; adjusted relative risk, 1.46; 95% confidence interval, 1.00-2.16), and an A1C <6.5% in late pregnancy compared with those living in less walkable communities (13% vs 9%; adjusted relative risk, 1.33; 95% confidence interval, 1.08-1.63). For individuals living in the most walkable communities, the median A1C was 7.5 (interquartile range, 6.0-9.4) in early pregnancy and 5.9 (interquartile range, 5.4-6.4) in late pregnancy. For those living in less walkable communities, the median A1C was 7.3 (interquartile range, 6.2-9.2) in early pregnancy and 6.2 (interquartile range, 5.6-7.1) in late pregnancy. Change in A1C across pregnancy was not associated with walkability.

CONCLUSION

Pregnant individuals with pregestational diabetes mellitus living in more walkable communities had better glycemic control in both early and late pregnancy. Whether community-level interventions to enhance neighborhood walkability can improve glycemic control in pregnancy requires further study.

Association of community-level food insecurity and glycemic control among pregnant individuals with pregestational diabetes

AIM

To evaluate whether pregnant individuals with pregestational diabetes who live in a food-insecure community have worse glycemic control compared to those who do not live in a food-insecure community.

METHODS

A retrospective analysis of pregnant individuals with pregestational diabetes enrolled in a multidisciplinary prenatal and diabetes care program. The exposure was community-level food insecurity per the Food Access Research Atlas. The outcomes were hemoglobin A1c (A1c) < 6.0 % in early and late pregnancy, and an absolute decrease in A1c ≥ 2.0 % and mean change in A1c across pregnancy.

RESULTS

Among 418 assessed pregnant individuals with pregestational diabetes, those living in a food-insecure community were less likely to have an A1c < 6.0 % in early pregnancy compared to those living in a community without food insecurity [16 % vs. 30 %; adjusted risk ratio (aRR): 0.55; 95 % CI: 0.33-0.92]. Individuals living in a food-insecure community were more likely to achieve a decrease in A1c ≥ 2.0 % [35 % vs. 21 %; aRR: 1.55; 95 % CI: 1.06-2.28] and a larger mean decrease in A1c across pregnancy [mean: 1.46 vs. 1.00; adjusted beta: 0.47; 95 % CI: 0.06-0.87)].

CONCLUSIONS

Pregnant individuals with pregestational diabetes who lived in a food-insecure community were less likely to enter pregnancy with glycemic control, but were more likely to have a reduction in A1c and achieve similar A1c status compared to those who lived in a community without food insecurity. Whether interventions that address food insecurity improve glycemic control and consequent perinatal outcomes remains to be studied.

Prediction of large-for-gestational-age infant by fetal growth charts and hemoglobin A1c level in pregnancy complicated by pregestational diabetes

OBJECTIVES

To compare the ability of three fetal growth charts (Fetal Medicine Foundation (FMF), Hadlock and National Institutes of Child Health and Human Development (NICHD) race/ethnicity-specific) to predict large-for-gestational age (LGA) at birth in pregnant individuals with pregestational diabetes, and to determine whether inclusion of hemoglobin A1c (HbA1c) level improves the predictive performance of the growth charts.

METHODS

This was a retrospective analysis of individuals with Type-1 or Type-2 diabetes with a singleton pregnancy that resulted in a non-anomalous live birth. Fetal biometry was performed between 28 + 0 and 36 + 6 weeks of gestation. The primary exposure was suspected LGA, defined as estimated fetal weight ≥ 90^th percentile using the Hadlock (Formula C), FMF and NICHD growth charts. The primary outcome was LGA at birth, defined as birth weight ≥ 90^th percentile, using 2017 USA natality reference data. The performance of the three growth charts to predict LGA at birth, alone and in combination with HbA1c as a continuous measure, was assessed using the area under the receiver-operating-characteristics curve (AUC), sensitivity, specificity, positive predictive value and negative predictive value.

RESULTS

Of 358 assessed pregnant individuals with pregestational diabetes (34% with Type 1 and 66% with Type 2), 147 (41%) had a LGA infant at birth. Suspected LGA was identified in 123 (34.4%) by the Hadlock, 152 (42.5%) by the FMF and 152 (42.5%) by the NICHD growth chart. The FMF growth chart had the highest sensitivity (77% vs 69% (NICHD) vs 63% (Hadlock)) and the Hadlock growth chart had the highest specificity (86% vs 76% (NICHD) and 82% (FMF)) for predicting LGA at birth. The FMF growth chart had a significantly higher AUC (0.79 (95% CI, 0.74-0.84)) for LGA at birth compared with the NICHD (AUC, 0.72 (95% CI, 0.68-0.77); P < 0.001) and Hadlock (AUC, 0.75 (95% CI, 0.70-0.79); P < 0.01) growth charts. Prediction of LGA improved for all three growth charts with the inclusion of HbA1c measurement in comparison to each growth chart alone (P < 0.001 for all); the FMF growth chart remained more predictive of LGA at birth (AUC, 0.85 (95% CI, 0.81-0.90)) compared with the NICHD (AUC, 0.79 (95% CI, 0.73-0.84)) and Hadlock (AUC, 0.81 (95% CI, 0.76-0.86)) growth charts.

CONCLUSIONS

The FMF fetal growth chart had the best predictive performance for LGA at birth in comparison with the Hadlock and NICHD race/ethnicity-specific growth charts in pregnant individuals with pregestational diabetes. Inclusion of HbA1c improved further the prediction of LGA for all three charts. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Differences in Hemoglobin A1c during Pregnancy between Non-Hispanic Black versus White Women with Prepregnancy Diabetes

OBJECTIVE

The objective of this was to determine whether the change in hemoglobin A1c (HbA1c) from early to late pregnancy differs between non-Hispanic Black and White women with prepregnancy diabetes.

STUDY DESIGN

A retrospective analysis was performed from an integrated prenatal and diabetes care program from 2012 to 2016. We compared HbA1c as a continuous measure and secondarily, HbA1c <6.5%, cross-sectionally, and longitudinally in early (approximately 10 weeks) and late (approximately 31 weeks) pregnancies. Linear and logistic regression were used and adjusted for age, body mass index, White diabetes class, medication use, diabetes type, gestational age at baseline HbA1c measurement, and baseline hemoglobin.

RESULTS

Among 296 non-Hispanic Black (35%) and White pregnant women (65%) with prepregnancy diabetes (39% type 1 and 61% type 2), Black women were more likely to experience increased community-level social determinants of health as measured by the Social Vulnerability Index (SVI) and were less likely to have type 1 diabetes and have more severe diabetes versus White women (p < 0.05). Black women had higher mean HbA1c (7.8 vs. 7.4%; beta: 0.75; 95% confidence interval [CI]: 0.30-1.19) and were less likely to have HbA1c < 6.5% at 10 weeks compared with White women (24 vs. 35%; adjusted odds ratio: 0.45; 95% CI: 0.24-0.81) but not after adjusting for SVI. At 31 weeks, both groups had similar mean HbA1c (both 6.5%) and were equally as likely to have HbA1c < 6.5% (57 vs. 54%). From early to late pregnancy, Black women had a higher percentage decrease in HbA1c (1.3 vs. 0.9%; beta = 0.63; 95% CI: 0.27-0.99) and were equally as likely to have an improvement or stable HbA1C < 6.5% from 10 to 31 weeks, with both groups having a similar mean HbA1c (6.5%) at 31 weeks.

CONCLUSION

Despite experiencing greater community-level social determinants of health, Black women with pregestational diabetes had a larger reduction in HbA1c and were able to equally achieve the target of HbA1c < 6.5% by late pregnancy compared with White women as part of an integrated diabetes and prenatal care program.

KEY POINTS

· An integrated diabetes and pregnancy care program may decrease racial and ethnic disparities in glycemic control.. · Black women had a larger reduction in HbA1c versus White women.. · Black women were able to equally achieve the target of HbA1c < 6.5% by late pregnancy versus White women..

Association of change in haemoglobin A1c with adverse perinatal outcomes in women with pregestational diabetes

AIMS

To determine whether a net decline in glycosylated haemoglobin (HbA_1c ) from early to late pregnancy is associated with lower risk of adverse perinatal outcomes at delivery among women with pregestational diabetes.

METHODS

A retrospective analysis from 2012 to 2016 at a tertiary care centre. The exposure was the net change in HbA_1c from early (<20 weeks gestation) to late pregnancy (≥20 weeks gestation). Primary outcomes were large for gestational age (LGA) and neonatal hypoglycaemia. The association between outcomes per 6 mmol/mol (0.5%) absolute decrease in HbA_1c was evaluated using modified Poisson regression, and adjusted for age, body mass index, White Class, early HbA_1c and haemoglobin and gestational age at HbA_1c measurement and delivery.

RESULTS

Among 347 women with pregestational diabetes, HbA_1c was assessed in early (9 weeks [IQR 7,13]) and late pregnancy (31 weeks [IQR 29,34]). Mean HbA_1c decreased from early (59 mmol/mol [7.5%]) to late (47 mmol/mol [6.5%]) pregnancy. Each 6 mmol/mol (0.5%) absolute decrease in HbA_1c was associated with a 12% reduced risk of LGA infant (30%, aRR:0.88; 95% CI:0.81,0.95), and a 7% reduced risk of neonatal hypoglycaemia (35%, aRR:0.93; 95% CI:0.87,0.99). Preterm birth (36%, aRR:0.93; 95% CI:0.89,0.98) and neonatal intensive care unit admission (55%, aRR:0.95; 95% CI:0.91,0.98) decreased with a net decline in HbA_1c , but not caesarean delivery, pre-eclampsia, shoulder dystocia and respiratory distress syndrome.

CONCLUSIONS

Women with pregestational diabetes with a reduction in HbA_1c may have fewer infants born LGA or with neonatal hypoglycaemia. Repeated assessment of HbA_1c may provide an additional measure of glycaemic control.

Association Between Social Vulnerability and Achieving Glycemic Control Among Pregnant Individuals With Pregestational Diabetes

OBJECTIVE

To evaluate the association between community-level social vulnerability and achieving glycemic control (defined as hemoglobin A1c [Hb A1c] less than 6.0% or less than 6.5%) among individuals with pregestational diabetes.

METHODS

We conducted a retrospective cohort of individuals with pregestational diabetes with singleton gestations from 2012 to 2016 at a tertiary care center. Addresses were geocoded using ArcGIS and then linked at the census tract to the Centers for Disease Control and Prevention's 2018 SVI (Social Vulnerability Index), which incorporates 15 Census variables to produce a composite score and four scores across thematic domains (socioeconomic status, household composition and disability, minority status and language, and housing type and transportation). Scores range from 0 to 1, with higher values indicating greater community-level social vulnerability. The primary outcome was Hb A1c less than 6.0%, and, secondarily, Hb A1c less than 6.5%, in the second or third trimesters. Multivariable Poisson regression with robust error variance was used to evaluate the association between SVI score as a continuous measure and target Hb A1c.

RESULTS

Among 418 assessed pregnant individuals (33.0% type 1; 67.0% type 2 diabetes), 41.4% (173/418) achieved Hb A1c less than 6.0%, and 56.7% (237/418) Hb A1c less than 6.5% at a mean gestational age of 29.5 weeks (SD 5.78). Pregnant individuals with a higher SVI score were less likely to achieve Hb A1c less than 6.0% compared with those with a lower SVI score. For each 0.1-unit increase in SVI score, the risk of achieving Hb A1c less than 6.0% decreased by nearly 50% (adjusted risk ratio [aRR] 0.53; 95% CI 0.36-0.77), and by more than 30% for Hb A1c less than 6.5% (adjusted odds ratio 0.67; 95% CI 0.51-0.88). With regard to specific SVI domains, those who scored higher on socioeconomic status (aRR 0.50; 95% CI 0.35-0.71) as well as on household composition and disability (aRR 0.55; 95% CI 0.38-0.79) were less likely to achieve Hb A1c less than 6.0%.

CONCLUSION

Pregnant individuals with pregestational diabetes living in an area with higher social vulnerability were less likely to achieve glycemic control, as measured by HgbA1c levels. Interventions are needed to assess whether addressing social determinants of health can improve glycemic control in pregnancy.