Lower limb trauma is an important cause of deep venous thrombosis in disaster refugees: The Great East Japan Earthquake deep vein thrombosis surveillance study

Introduction: The aim of this study is to clarify the important role of deep venous thrombosis (DVT) in disaster refugees. Methods: We visited the Minami-sanriku Tome shelter in Miyagi Prefecture, one of the areas affected by the Great East Japan Earthquake, to examine the incidence of DVT by using an ultrasound device from March 14 to May 4, 2011. One hundred eighty-seven people, who were aged over 60 years and had lower limb trauma, lower limb symptoms, a history of lengthy periods of resting inside a car, and/or a motionless lifestyle in the shelter, participated in the examination. The ultrasound examination was mainly intended to check for DVT findings below the knee. Results: The incidence of DVT in the participants was 5.3% (10/187). When comparing those with DVT with those without, age, percentage of women, and percentage with lower limb trauma were significantly higher in DVT patients than in non-DVT people. After logistic regression analysis, lower limb trauma was an independent strong risk factor for DVT (p < 0.0001, odds ratio=26.5). Conclusion: In conclusion, lower limb trauma is the most important cause of DVT formation in disaster refugees.