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 thrombo-embolic 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 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. Thrombo-embolic 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 (aOR 2.19, 95%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 thrombo-embolic events in pregnancy. Key Words Type 1 Diabetes Mellitus, VTE, thromboembolism, pregnancy.