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.