Prolonged travel and venous thromboembolism findings from the RIETE registry

There is a lack of information on clinical risk factors for venous thromboembolism (VTE) development following prolonged traveling. Clinical characteristics and additional risk factors for VTE in travelers were analyzed in RIETE, an ongoing registry of patients with symptomatic, confirmed acute VTE. Of 26,172 patients enrolled in RIETE as of May 2009, 2% developed VTE in association with recent traveling. Travelers were ten years younger, had significantly more previous VTE events (20% vs. 16%; OR: 1.4; 95%CI: 1.1-1.7) and their body mass index (BMI) was 28.4 ± 5.1 vs. 27.7 ± 5.2 in other patients from the registry (P = 0.004). 115 (20%) of recent travelers had previous VTE compared to 16% among others patients (OR: 1.4; 95%CI: 1.1-1.7). Recent travelers used hormones significantly more frequently (8.7% vs. 3.7%; OR: 2.5; 95% CI: 1.8-3.3) and more often had a positive thrombophilia test (16% vs. 8.7%; OR: 2; 95%CI: 1.6-2.6). Travelers used LMWH prophylaxis significantly less frequently than other patients in the registry (2.4% vs. 13%; OR 0.2; 95%CI: 0.1-0.3). There were differences in VTE risk in professional drivers compared to passengers. The current study demonstrates four risk factors for VTE development after long traveling: high BMI, previous VTE, hormone use and thrombophilia. Studies of prophylactic antithrombotic therapy in high risk travelers are warranted.