Abstract and Introduction
Abstract
Objectives: Racial disparities in preexisting diabetes mellitus (PDM) and gestational diabetes mellitus (GDM) remain largely unexplored. We examined national PDM and GDM prevalence trends by race/ethnicity and the association between these conditions and fetal death.
Methods: This was a retrospective cross-sectional analysis of 69,539,875 pregnancy-related hospitalizations from 2002 to 2017 including 674,040 women with PDM (1.0%) and 2,960,797 (4.3%) with GDM from the US Nationwide Inpatient Sample Survey. Joinpoint regression was used to evaluate trends in prevalence. Survey logistic regression was used to evaluate the association between exposures (PDM and GDM) and outcome.
Results: Overall, the average annual increase in prevalence was 5.2% (95% confidence interval [CI] 4.2–6.2) for GDM and 1.0% (95% CI −0.1 to 2.0) for PDM, during the study period. Hispanic (average annual percentage change 5.3, 95% CI 3.6 − 7.1) and non-Hispanic Black (average annual percentage change 0.9, 95% CI 0.1 − 1.7) women had the highest average annual percentage increase in the prevalence of GDM and PDM, respectively. After adjustment, the odds of stillbirth were highest for Hispanic women with PDM (odds ratio 2.41, 95% CI 2.23–2.60) and decreased for women with GDM (odds ratio 0.51, 95% CI 0.50–0.53), irrespective of race/ethnicity.
Conclusions: PDM and GDM prevalence is increasing in the United States, with the highest average annual percentage changes seen among minority women. Furthermore, the reasons for the variation in the occurrence of stillbirths among mothers with PDM and GDM by race/ethnicity are not clear and warrant additional research.
Introduction
Diabetes mellitus (DM) is recognized as one of the most common metabolic disorders of pregnancy, affecting 17% of pregnancies globally.[1] Gestational DM (GDM), a condition defined by the American College of Obstetricians and Gynecologists as carbohydrate intolerance during pregnancy, makes up most of the cases of pregnancy-associated DM.[2] Data suggest that approximately 86% of pregnancy-associated DM is caused by GDM, whereas approximately 14% is caused by DM diagnosed prepregnancy.[1] In part because of the greater prevalence of GDM compared with prepregnancy DM (PDM), the majority of research on pregnancy-associated DM has focused on maternal morbidity and fetal outcomes among women with GDM. We know from previously published data that women diagnosed as having GDM have an increased risk for several adverse outcomes, including stillbirth, fetal overgrowth, preterm birth, preeclampsia, and progression to type 2 DM later in life.[3–5] The data also suggest that children born to mothers with GDM are at increased risk for obesity, cardiovascular disease, and type 2 DM later in life.[3,4] Women with PDM are reported to be at a significantly increased risk for preeclampsia, congenital malformations, fetal overgrowth, and fetal death.[6–16] These data raise serious concerns given that the number of women with PDM is increasing, irrespective of diabetes subtype (type 1 insulin-dependent, or type 2 noninsulin dependent).[6,9,10,17]
The risks accompanying pregnancy-associated DM have been reported to disproportionately affect women from different races/ethnicities. Some studies have indicated that non-White races/ethnicities have a higher prevalence of PDM and GDM than White women.[9,18–20] Consequently, women of different racial and ethnic backgrounds, such as Black and South Asian with PDM and GDM, also have been shown to be at an increased risk for adverse fetal outcomes, including perinatal loss, preterm delivery, respiratory distress syndrome, and fetal anomalies.[21–23] The majority of these studies focused solely on GDM and assessed women from a limited geographic region, however. As a result, these data highlight the need for further research to better characterize existing racial/ethnic disparities.
We sought to expand the depth and breadth of the current understanding of racial and ethnic differences in the prevalence of both PDM and GDM, by using hospital data to examine national trends in prevalence by race/ethnicity. We also examined the association between these conditions, race/ethnicity, and stillbirth.
South Med J. 2022;115(7):405-413. © 2022 Lippincott Williams & Wilkins
