Assessing the impact of COVID-19 pandemic on ambulance transports for self-harm: a population-based study in Osaka Prefecture, Japan

Shunichiro Nakao; Yusuke Katayama; Tetsuhisa Kitamura; Kenta Tanaka; Tomoya Hirose; Jotaro Tachino; Taku Iwami; Jun Masui; Hisaya Domi; Takeshi Shimazu; Jun Oda; Tetsuya Matsuoka

doi:10.1136/bmjopen-2023-074903

Assessing the impact of COVID-19 pandemic on ambulance transports for self-harm: a population-based study in Osaka Prefecture, Japan

BMJ Open. 2023 Sep 12;13(9):e074903. doi: 10.1136/bmjopen-2023-074903.

Authors

Shunichiro Nakao^{1

2}, Yusuke Katayama^{3

2}, Tetsuhisa Kitamura^{2

4}, Kenta Tanaka^{2

4}, Tomoya Hirose^{3

2}, Jotaro Tachino^{3

2}, Taku Iwami^{2

5}, Jun Masui^{2

6}, Hisaya Domi², Takeshi Shimazu⁷, Jun Oda³, Tetsuya Matsuoka^{2

8}

Affiliations

¹ Department of Traumatology and Acute Critical Medicine, Osaka University Faculty of Medicine Graduate School of Medicine, Suita, Osaka, Japan shunichironakao@hp-emerg.med.osaka-u.ac.jp.
² The Working Group to Analyze the Emergency Medical Care System in Osaka Prefecture, Osaka, Japan.
³ Department of Traumatology and Acute Critical Medicine, Osaka University Faculty of Medicine Graduate School of Medicine, Suita, Osaka, Japan.
⁴ Department of Social and Environmental Medicine, Osaka University Faculty of Medicine Graduate School of Medicine, Suita, Osaka, Japan.
⁵ Health Service, Kyoto University, Kyoto, Japan.
⁶ Department of Emergency Medicine, Tane General Hospital, Osaka, Japan.
⁷ Osaka General Medical Center, Osaka, Japan.
⁸ Rinku General Medical Center, Izumisano, Osaka, Japan.

Abstract

Objectives: The COVID-19 pandemic might have affected emergency medical services transports for self-harm in Japan. However, the available data are insufficient to fully understand the pandemic's impact on ambulance transports due to self-harm. This study aimed to investigate the change in the incidence of ambulance transports for self-harm from 2018 to 2021 and to identify vulnerable age groups during the pandemic.

Design: A population-based observational study using a database from the Osaka Prefectural Government.

Setting: The database covers the entire area of Osaka Prefecture and included information on ambulance transports and hospital details.

Participants: Ambulance transport of patients due to self-harm from 2018 through 2021 was investigated.

Primary outcome measures: The primary outcome was the incidence of ambulance transport for self-harm.

Results: We analysed 10 843 patients. Their median age was 38 years, and 69.0% were female. We observed an increasing trend of the incidence rate in cases per 100 000 population per year from 29.4 in 2018 to 31.2 in 2021. However, after adjusting for age group, sex and month, there was no difference in the incidence of ambulance transport due to self-harm in 2019 (adjusted incidence rate ratio (aIRR) 1.007; 95% CI 0.955 to 1.063), 2020 (aIRR 1.041; 95% CI 0.987 to 1.098) and 2021 (aIRR 1.022; 95% CI 0.968 to 1.078), compared with 2018. We observed no difference in 21-day mortality from 2018 through 2021. In the age group of 20-29 years, despite no difference in 2019 compared with 2018, we found an 11.7% increase in the incidence of ambulance transport due to self-harm in 2020 (aIRR 1.117; 95% CI 1.002 to 1.245) and no difference in 2021.

Conclusions: There was no difference in the incidence of ambulance transport due to self-harm and 21-day mortality from 2018 through 2021. However, the incidence rate of ambulance transport due to self-harm in 2020 increased in the age group of 20-29 years.

Keywords: ACCIDENT & EMERGENCY MEDICINE; COVID-19; MENTAL HEALTH; Suicide & self-harm.

Publication types

Observational Study
Research Support, Non-U.S. Gov't

MeSH terms

Adult
Ambulances
COVID-19* / epidemiology
Female
Humans
Japan / epidemiology
Male
Pandemics
Self-Injurious Behavior* / epidemiology
Young Adult

Substances

CI 987