673 The Peripartum Risk of Deep Vein Thrombosis and Pulmonary Embolism in Women With Inflammatory Bowel Disease: A Population-Based Cohort Analysis

Abstract

INTRODUCTION: Population-based adverse outcomes in the peripartum period are limited. Both Inflammatory Bowel Disease (IBD) and pregnancy are known risk factors for venous thromboembolism (VTE), encompassing deep vein thrombosis (DVT) and pulmonary embolism (PE). The aim of our study was to determine whether the odds of VTE are higher in women with Ulcerative Colitis (UC) and Crohn's disease (CD) at the time of delivery, compared to pregnant patients without IBD. METHODS: We performed a population-based retrospective cohort study using the Healthcare Cost and Utilization Project (HCUP)'s Nationwide Inpatient Sample (NIS) between 2005 and 2014. ICD-9-CM diagnosis and procedure codes were used to identify unique obstetric hospitalizations associated with delivery of an infant, and VTE. We created national estimates using appropriate weights for each NIS admission. Multivariable logistic regression was used to evaluate the association of UC and CD with VTE, while adjusting for age, race, smoking, obesity, Charlson Comorbidity Index, chronic steroid use, income, primary insurance, hospital region, and hospital bed size. RESULTS: The cohort comprised of 39.8 million deliveries, including 19,167 in women with UC and 31,083 in women with CD. Table 1 depicts baseline characteristics of the cohort. Overall, IBD patients were more likely to be white, have private insurance, receive care at larger hospitals, have a cesarean section and use chronic steroids compared to non-IBD patients. There were 19 (0.1%) cases of VTE in UC patients, 18 (0.06%) in CD patients versus 11,935 (0.03%) in non-IBD patients. Unadjusted odds ratios [OR] were 4.0 for UC; 95% confidence interval [CI] 1.5-10.5, and 2.5 (95% CI, 0.9-6.8) for CD. After adjusting for confounders, the OR for developing VTE was 1.63 (95% CI 0.41-6.55) among UC patients and 2.11 (95% CI, 0.79-5.64) in CD patients. As seen in Table 2, the following variables were associated independently with an increased risk for VTE: age, higher comorbidity scores, inpatient cesarean delivery, obesity and smoking. CONCLUSION: Our study showed that patients with IBD were not at greater risk for VTE at the time of delivery compared with non-IBD, perhaps due to the lower absolute risk of VTE over time (0.06-0.1% in our study vs 1.5-2.1% in the 2005 NIS database). Improved awareness and practices surrounding DVT prophylaxis may also be contributing. This study was not able to differentiate between active versus quiescent disease.