Gestational Diabetes and Risk of Stroke Among US Black Women

There is a paucity of evidence on whether gestational diabetes (GDM) is a risk factor for cerebral vascular disease for Black women and lack of data on incident stroke as end point.

We conducted a large prospective cohort study of Black women across the United States and assessed the association between self-reported history of GDM and incident stroke. The study began when participants became parous or enrolled in 1995. We followed up 41 143 parous Black women who were free of cerebral vascular disease or cancer and followed up until incident stroke, death, or the end of 2021. Our exposure was self-reported history of GDM, and outcome was incident stroke. Multivariable Cox proportional hazards model was used to estimate hazard ratios (HRs) and 95% CIs, adjusting for major known risk factors for stroke.

A total of 1495 incident stroke cases were identified among 41 143 Black women from 1995 until 2021 (881 505 person-years of follow-up). Black women with a history of GDM had a consistent 1.4-fold increased risk of stroke compared with those with a healthy pregnancy (age-adjusted HR, 1.44 [95% CI, 1.14-1.82]; multivariable HR, 1.41 [95% CI, 1.11-1.79]). Compared with healthy parous women with neither GDM nor type 2 diabetes, women with a history of both had a 2.6-fold increased stroke risk (multivariable HR, 2.59 [95% CI, 1.88-3.57]); women with only type 2 diabetes have 2-fold increased stroke risk (multivariable HR, 2.04 [95% CI, 1.79-2.32]); women with a history of GDM but no progression to type 2 diabetes do not have an increased risk of stroke (multivariable HR, 1.22 [95% CI, 0.86-1.73]).

In this large prospective study of Black women, a vulnerable population at high risk for stroke, a history of GDM increased stroke incidence by 41%. There was no elevated risk of stroke for Black women with a history of GDM and no progression to type 2 diabetes, while the stroke risk increased by 2.6-fold for Black women with GDM and progression to type 2 diabetes. Our results highlight the importance of consideration of history of GDM for stroke early prevention, especially Black women with progression to T2DM after GDM.