Risk of cardiovascular events after gestational diabetes: a retrospective population study

To investigate whether the risk for post-partum cardiovascular diseases (CVD) is driven by gestational diabetes (GDM), by GDM-related risk factors and/or by pre-gestational (Pre-GD) or post-gestational diabetes (Post-GD).

Women delivering in Tuscany, Italy in years 2010-2012 (n = 74,720), were identified from certificates of care at delivery and further identified as affected with GDM, Pre-GD or Post-GD through regional administrative databases. Women with GDM, Pre-GD or Post-GD were retrospectively evaluated for risk of post-partum hospitalizations for CVD (myocardial infarction or stroke; n = 728) across years 2013-2021, comparing women with different forms of diabetes to those without diabetes. Risk of CVD was assessed as odds ratio (OR 95% CI), after logistic multivariate models, considering all recorded pre-gestational characteristics as covariates.

The adjusted OR (aOR) for post-partum CVD hospitalizations was not significantly related to GDM itself (aOR: 0.85; 0.64-1.12; p = ns), but increased in women with Pre-GD (aOR: 2.02; 1.09-3.71; p = 0.024) and Post-GD, associated or not to prior GDM (aOR; 4.21; 2.45-7.23 and respectively aOR: 3.80; 2.38-6.05; p < 0.0001 for both). In presence of pre-pregnancy maternal obesity (BMI ≥ 30 kg/m²) the aOR of CVD approximatively doubled (aOR: 1.90; 1.51-2.40); p < 0.0001, independently of GDM and of Post-GD. The adjusted risk of CVD was lower among employed women (aOR: 0.83; 0.70-0.99); p = 0.04 and significantly higher in presence of poorer education levels (aOR: 1.32; 1.11-1.57); p < 0.0001.

In this population the risk of post-partum CVD was driven by Pre- and Post-GD, not by GDM alone. Pre-gestational obesity represented a major independent risk factor for post-partum CVD.