Risk Factors Associated with Delivery Hospitalization Pulmonary Embolism

The objectives of this study were to analyze trends in obstetric pulmonary embolism (PE) and to determine how clinical risk factors have contributed to changes in PE risk over the study period.

The 2000-2021 National Inpatient Sample was used for this cross-sectional analysis. Delivery hospitalizations of patients aged 15 to 54 years were identified. Trends in pulmonary embolism and associated risk factors were estimated with joinpoint regression, which calculated trends as the average annual percent change (AAPC) with 95% CIs. Risk factors analyzed included chronic conditions such as thrombophilia, prior venous thromboembolism events, obesity, and chronic heart disease as well as a range of obstetric complications. A multivariate logit decomposition model analysis was performed to determine the contribution of individual risk factors to increasing risk for PE over the study period.

The rate of PE increased significantly over the study period among both vaginal deliveries (AAPC 6.4%, 95% CI 5.0%, 7.6%) and cesarean deliveries (AAPC 5.3%, 95% CI 4.1%, 6.8%). In decomposition analysis, the increasing prevalence of chronic conditions and obstetric complications accounted for 39.2% of the increased PE risk among vaginal deliveries and 54.4% of the increased PE risk among cesarean deliveries. Among vaginal deliveries, growing obesity prevalence accounted for the most increased risk (15.3%). Among cesarean deliveries, increase in chronic heart disease (12.8%), hypertensive disorders of pregnancy (10.5%), blood transfusion (9.8%), and obesity (8.8%) accounted for the most increased risk. A decrease in postpartum infections among cesarean deliveries accounted for decreased PE risk (-11.3%).

PE increased significantly over a 22-year study period in this analysis of nationally representative obstetric delivery data. A large portion of the increase in PE could be accounted for by the increasing prevalence of PE risk factors, although risk associated with postpartum cesarean infections decreased over the study period.

· PE increased significantly over 22 years among both vaginal and cesarean deliveries.. · Rising risk factor prevalence, especially obesity, explains much of the increased PE risk.. · Cesarean PE increase reflects genuine clinical trends, not ICD-9 to ICD-10 coding transition artifact..