Increased risk of deep vein thrombosis and pulmonary thromboembolism in patients with aortic aneurysms: A nationwide cohort study.

Feng-You Lee,Chao-Hsien Chen,Chia-Hung Kao,Wei-Kung Chen,Ching-Yuan Lai,Chun-Hsiang Chiu,Tse-Yen Yang,Cheng-Li Lin,Rudolf Kirchmair

doi:10.1371/journal.pone.0178587

Abstract

Studies on the association between aortic aneurysm (AA) and the subsequent risk of venous thromboembolism (VTE) are limited to a few case reports and investigations which only focused on surgical effects. Therefore, we used the National Health Insurance Research Database to clarify whether patients with AAs have a heightened risk of subsequent VTEs, including deep vein thrombosis (DVT) and pulmonary embolism (PE). Our retrospective cohort study comprised patients aged ≥ 18 years who received a diagnosis of an AA and were hospitalized at any point during 2000–2010 (n = 16,630). Each AA patient was frequency-matched to 4 non-AA hospitalized patients based on age, sex, and index year (n = 66,453). The Cox proportional hazard regressions model was used to estimate the adjusted effect of AAs on VTE risk. The overall incidence of DVT and PE was higher in the patients with AA than in the non-AA group patients (23.5 versus 13.2 and 13.5 versus 7.98/1,000 person-years). After adjustment for age, sex, duration of hospitalization in the study period, and comorbidities, patients with AAs were associated with a 1.88-fold higher risk of DVT and 1.90-fold higher risk of PE compared to the non-AA cohort. Patients with abdominal AAs were more likely to develop DVT, whereas thoracic AA patients were more likely to develop PE. A diagnosis of a ruptured AA was associated with a substantially increased risk of DVT. Surgical treatment of AAs was associated with a heightened risk of VTE within 6-months post-operation. Our study demonstrates that AAs are associated with an increased risk of subsequent VTE. Future investigations are encouraged to delineate the mechanisms underlying this association and to evaluate the cost-effectiveness of screening for VTEs in patients with AAs.

Highlights

An aortic aneurysm (AA) is defined as a loss of aortic wall integrity, which results in the permanent and irreversible focal dilatation of vessel walls [1, 2]
We evaluated the risk of deep vein thrombosis (DVT) and pulmonary embolism (PE) for AA patients compared with non-AA patients by using multivariable Cox proportional hazard models with results presented as adjusted hazard ratios (HRs) and 95% confidence intervals (CIs)
The duration of hospitalization was longer for AA patients than non-AA subjects (57.9 vs. 37.0 days) in the study period

Summary

Introduction

An aortic aneurysm (AA) is defined as a loss of aortic wall integrity, which results in the permanent and irreversible focal dilatation of vessel walls [1, 2]. Most AAs are silent until they dissect or rupture, leading to life-threatening complications [3, 4]. In the United States, approximately 4,500 patients die of ruptured abdominal AAs (AAAs) annually and another 1,400 die from reparative and preventive repair surgery, creating a burden to the health care system [1, 5]. Venous thromboembolisms (VTEs), comprising deep vein thrombosis (DVT) and pulmonary embolisms (PEs), are a relatively common cause of death worldwide. DVT involves the formation of blood clots in the deep venous system and frequently causes swelling, pain, a lukewarm sensation, and venous engorgement of the lower extremities. Accepted predisposing factors for VTEs can be grouped into 3 categories, termed the “Virchow’s triad”: endothelial injury, stasis of blood flow and, hypercoagulability [9]

Methods

Results

Discussion

Conclusion