Incidence and characteristics of self-harm during the 3-year period of COVID-19-related social distancing in the Republic of Korea.

Background: Suicide is a leading cause of mortality worldwide, and self-harm is a key risk factor. Continuous monitoring of self-harm trends facilitates effective prevention. During the coronavirus disease pandemic, social distancing significantly influenced self-harm incidence. This study aimed to compare self-harm rates and patient characteristics in 3-year prepandemic and pandemic periods (2017-2019 and 2020-2022, respectively).

Methods: We retrospectively analysed and subdivided the data over 6 years into 3-month intervals, obtained from the Emergency Department (ED)-based Injury In-depth Surveillance database, South Korea, to examine changes in the incidence of self-harm in patients visiting the ED from the prepandemic to pandemic period and compared the characteristics of patients who attempted self-harm and risk factors for in-hospital mortality.

Results: Among 8 02 032 patients (age: 18-64 years), we identified 45 535 patients with self-harm injuries (overall rate: 5.68%), which significantly increased during the pandemic (4.6% (21 852) in 2017-2019 to 7.2% (n=23 683) in 2020-2022). Age-group-stratified comparisons showed increased self-harm incidence across all age groups, especially among women younger than 30 years, during the pandemic period. The proportion of self-harm attributed to psychological problems increased markedly. However, the two periods showed no significant difference in the in-hospital mortality.

Discussion and conclusion: The incidence of self-harm significantly increased and remained consistently higher in patients visiting EDs throughout the pandemic period than during the 3 years prepandemic, even after the relaxation of social distancing measures. Young women primarily drove this increase, and psychological problems constituted a major risk factor.