Temporal Trends in Treatment Interruption among the Victims of Heavy Rain Disasters in Japan: Findings from Emergency Medical Team Data.

Objectives: Treatment interruptions in disaster victims are concerning, owing to an increase in natural disasters and the growing elderly population with chronic conditions. This study examined the temporal trends in treatment interruptions among victims of 2 recent major heavy rain disasters in Japan: West Japan heavy rain in 2018 and Kumamoto heavy rain in 2020.

Methods: Data for this study were derived from the national standardized medical data collection system called the "Japan Surveillance in Post-Extreme Emergencies and Disasters." Joinpoint regression analysis was performed to examine the daily trends in treatment interruptions reported soon after each disaster onset.

Results: A total of 144 and 87 treatment interruption cases were observed in the heavily affected areas of the West Japan heavy rain in 2018 and Kumamoto heavy rain in 2020, respectively. In both disasters, a high number of treatment interruption cases were observed on the first day after the disaster. Joinpoint regression analysis showed that trends in the percentage of treatment interruptions differed between the 2 disasters at different disaster scales.

Conclusions: The findings suggest the importance of a prompt response to treatment interruptions in the immediate aftermath of a disaster and consideration of the specific characteristics of the disaster when planning for disaster preparedness and response.