Impact of the COVID-19 pandemic and subsequent social restrictions on ambulance calls for suicidal and nonsuicidal self-harm: A population-based study in Osaka prefecture, Japan

Aim Self-harm is a common ambulance call and is potentially affected by the COVID-19 pandemic. The aim of this study was to investigate whether the incidence of ambulance transport due to self-harm increased in 2020. Methods We undertook a population-based observational study using a database from the Osaka prefectural government. Ambulance transport of patients due to self-harm from 2016 through 2020 was investigated. We estimated adjusted incidence rate ratios using a Poisson regression model to compare the annual incidence rates of ambulance transport in 2017–2020 with those in 2016. We also provided age-stratified analysis. Results We analyzed 13,648 patients. There was no difference in the incidence of ambulance transport due to self-harm in 2017, 2018, 2019, and 2020 compared with 2016. In the age group of 20–29 years, despite no difference in 2017–2019 compared with 2016, we found a 13.8% increase in the incidence of ambulance transport due to self-harm in 2020 (adjusted incidence rate ratio, 1.138; 95% confidence interval, 1.025–1.265). Conclusions Although there was no difference in the incidence of ambulance transport due to self-harm in 2017–2019, that in 2020 increased in the age group of 20–29 years.