Type 1 Diabetes Mellitus and Thromboembolism in Pregnancy

Objective The impact of type 1 DM (T1DM) on thromboembolism in pregnancy is uncertain. We hypothesized that T1DM is associated with higher rates of thrombotic events during pregnancy and the postpartum period. Study design This is a retrospective cohort study utilizing the National Inpatient Sample database from HCUP/AHRQ for 2017-2019. Pregnant and postpartum patients with a history of T1DM were compared to those without. The primary outcome was a composite diagnosis of any thrombotic disease (pulmonary embolism [PE], deep vein thrombosis [DVT], cerebral vascular thrombosis [CVT], or other thromboses). Secondary outcomes were the diagnosis of each individual type of thromboembolic event. Groups were compared via student's test, chi-squared, and logistic regression analyses, controlling for confounders including age, race, obesity, tobacco use, cHTN, asthma, anemia, and cesarean section. Results A total of 2,361,711 subjects met the criteria. Patients with T1DM encompassed 0.4% of subjects (n = 9,983). T1DM subjects were more likely to be younger, non-Hispanic white, obese, tobacco users, chronic hypertensive, asthmatic, and have a history of cesarean (all p < 0.001). They were less likely to be in the top income quartile. Thromboembolic events occurred more frequently in those with T1DM (0.45% vs. 0.20%, p < 0.001). DVT was the most common event (0.25%). After controlling for confounders, T1DM remained independently associated with any thromboembolic event in pregnancy (adjusted odds ratio [aOR] = 2.19, 95% confidence interval [CI]: 1.49-3.23), PE (aOR = 3.59, 95% CI: 1.65-7.82), and DVT (aOR = 2.43, 95% CI: 1.43-4.14). Conclusion T1DM is associated with an increased risk of thromboembolic events in pregnancy.