Abstract
In post-disaster evacuation settings, the risk of venous thromboembolism increases because of reduced physical
activity and dehydration, making early detection and prevention of deep vein thrombosis (DVT) in shelters
essential. In this study, we used DVT screening data collected in shelters in Shika Town, Ishikawa Prefecture,
after the 2024 Noto Peninsula Earthquake to examine temporal changes in DVT positivity and D-dimer levels, as
well as background and shelter environmental factors associated with DVT positivity. From January 28 to March
25, 2024, 155 participants underwent interviews, 110 underwent venous ultrasonography, and 124 underwent
D-dimer testing; shelter conditions were also assessed retrospectively. Follow-up screening was conducted in
January 2025. Overall, 13.6% of participants were positive for DVT during the study period. The positivity rate
reached its highest level on January 28 (22.7%), declined, and then increased again in late March. D-dimer levels
were also highest on the same date. Age and D-dimer levels were significantly higher in the DVT-positive group
than in the DVT-negative group. One year after the disaster, no participants were positive for DVT, and D-dimer
levels decreased significantly. In the shelter environment analysis, designated shelter status was significantly
associated with a lower DVT positivity rate, while the provision of warm meals and the availability of a communal
dining area also showed negative associations. These findings suggest that early post-disaster shelter-based
screening is useful for early DVT detection and that comprehensive interventions, including individual-level measures
and improvements in shelter conditions, are important for DVT prevention in disaster settings.
