A nationwide survey concerning the mortality and risk of progressing severity due to arterial and venous thromboembolism in inflammatory bowel disease in Japan

Background: The mortality and risk factors of severe disease and death due to arterial and venous thromboembolism (ATE and VTE, respectively) in patients with inflammatory bowel disease (IBD) remain unclear, especially in Asia. Aims: This study aimed to reveal the mortality and risk factors of TE in IBD patients in Japan. Methods: In the primary surveillance, responses to questionnaires regarding the number of cases of severe TE and TE-associated death in IBD patients in a span of over the past 10 years were obtained from 32 institutions in Japan. In the secondary surveillance, detailed data about IBD patients with TE were collected. The characteristics, laboratory data, therapy status, and situation at the time of TE development were retrospectively collected, and the data were compared between the patients with and without severe TE and TE-associated death. Results: The incidence of TE was 1.89% among 31,940 IBD patients. The frequencies of severe TE and TE-associated mortality were 10.7% and 1.0% among the total IBD and TE with IBD patients, respectively. The only risk factor for severe ATE and ATE-associated death was ischemic heart disease. The independent risk factors for severe VTE and VTE-associated death were age (≤ 45 years old), the site of VTE, and disease severity, with anti-TNF therapy as a potential negative risk factor. Patients with severe VTE had a high risk of developing persistent VTE and sequelae. Conclusion: Unlike ATE, the incidence of VTE was comparable in Asian and Western countries. Therapeutic and prophylactic strategies for managing IBD-associated TE in Asia are urgently needed.