Impact of non-pharmaceutical interventions for the COVID-19 pandemic on emergency department patient trends in Japan: a retrospective analysis.

AIM: The coronavirus disease (COVID-19) pandemic massively impacted emergency department (ED) visits. The unavailability of specific therapies or vaccines has made non-pharmaceutical interventions (NPIs) an alternative strategy for COVID-19. We assessed the impact of NPIs (nationwide school closures and state of emergency) on ED visits during the COVID-19 pandemic in Japan. METHODS: This retrospective study compared the trends in ED visits from 1 January to 25 May, 2020 (during the pandemic) with the average during 2015-2019 (before the pandemic). The primary end-point was the change in the number of ED visits during the COVID-19 pandemic with those from before the pandemic, with the NPI application stratified across four periods in 2020: Period 0 (1-15 January), no COVID-19 cases detected in Japan; Period I (16 January-1 March), initial COVID-19 outbreak; Period II (2 March-15 April), nationwide school closures; Period III (16 April-25 May), state of emergency. RESULTS: Compared with before the pandemic, the number of walk-in ED visits significantly decreased by 23.1%, 12.4%, and 24.0% (4,047 versus 3,111; 3,211 versus 2,813; and 3,384 versus 2,573; P < 0.001 for all) in Periods I, II, and III, respectively. The number of ambulance ED visits during the pandemic significantly increased by 8.3% in Period I (1,814 versus 1,964, P = 0.002), whereas there was no significant change in Periods II and III with 2.7% and -3.1% (1,547 versus 1,589 and 1,389 versus 1,346; P = 0.335 and P = 0.284, respectively). CONCLUSIONS: The application of an NPI during the COVID-19 pandemic could have significantly reduced patient attendance in the ED.