Policy levers to reduce racial-ethnic inequities in diabetes after gestational diabetes

Project Summary Gestational diabetes (GDM) is a common complication of pregnancy with substantial racial-ethnic disparities, with women of color facing the greatest disadvantage. These GDM disparities have profound implications for life course disparities in type 2 diabetes (T2DM) and cardiovascular disease. Recently we conducted a novel data linkage between New York City birth certificate and HbA1c registry databases to construct a multiethnic population-based cohort to follow women after delivery from 2009-2017, the A1c in Pregnancy and Postpartum Linkage for Equity (APPLE) NYC Cohort. When following women with GDM, we found stark racial-ethnic disparities in progression to T2DM, with Black, Latina, and South Asian women having 2 to 4.5 times the risk of non-Latina White women. Despite these important findings, very little is known about what causes disparities to emerge in the years after a GDM pregnancy. Current research focuses on individual risk; however, it does not identify neighborhood contextual risk factors to inform targets for policy intervention and lacks racial-ethnic diversity. Structural inequities and neighborhood context may be especially potent in the postpartum period, as women of color often face social and economic challenges while their bodies recover and continue to evolve physiologically. Identifying policy levers to intervene "upstream” during the critical postpartum period has the potential to dismantle structural inequities that drive individual level T2DM risk factors. Therefore, we propose a concurrent mixed-methods study, leveraging our retrospective cohort of 21,695 multiethnic women with GDM, the APPLE NYC Cohort, qualitative interviews with postpartum women, and an innovative systems science modeling approach. Our overall goal is to identify policy levers to prevent progression to T2DM after GDM in the postpartum period and reduce racial-ethnic disparities. First, we will use data from the APPLE NYC cohort, to measure associations between social and built environment and longitudinal T2DM outcomes after GDM. Next, we will explore the lived experiences of women of color in the years following a GDM pregnancy by conducting in-depth interviews with Black, Latina, and South Asian women who experienced GDM during pregnancy, including those who have and have not progressed to T2DM, up to 10 years postpartum. Finally, we will develop an agent-based model to assess and compare potential policy interventions to improve T2DM outcomes after GDM and reduce racial-ethnic disparities. To do so we will identify a set of policy scenarios to alter structural inequities in the social and built environment, use the agent-based model to assess the impact on the risk of T2DM inequities, and will utilize the APPLE NYC cohort to validate the model. Our proposed study not only fills gaps in targeted research in the prevention of T2DM, but also shifts the paradigm of post- GDM T2DM prevention to an ecosocial framework. Our findings will be a key resource for policymakers on how to disrupt progression from GDM to T2DM and reduce life course racial-ethnic inequities.