Impact of the COVID-19 and psychological risk factors on non-suicidal self-injury behavior among high school students: a one-year follow-up study

OBJECTIVES: Non-suicidal self-injury (NSSI) behavior is a severe public health issue in adolescents. This study investigated the possible impact of the coronavirus disease 2019 (COVID-19) and analyzed psychological risk factors on adolescent NSSI. METHODS: A one-year follow-up study was conducted in September 2019 (Time 1) and September 2020 (Time 2) among 3588 high school students. The completed follow-up participants (N = 2527) were classified into no NSSI (negative at both time points), emerging NSSI (negative at Time 1 but positive at Time 2), and sustained NSSI (positive at both time points) subgroups according to their NSSI behaviors before and during the COVID-19 pandemic. Perceived family functioning, perceived school climate, negative life events, personality traits (neuroticism, impulsivity, and self-control) were assessed using self-report scales. RESULTS: The data indicated an increase (10.3%) in the incidence of NSSI. Compared to no NSSI subjects, the emerging NSSI and sustained NSSI subgroups had lower perceived family functioning, higher neuroticism, higher impulse-system but lower self-control scores, and more negative life events. Logistic regressions revealed that after controlling for demographics, neuroticism and impulse-system levels at Time 1 positively predicted emerging NSSI behavior, and similarly, higher neuroticism and impulsivity and lower self-control at Time 1 predicted sustained NSSI behavior. CONCLUSIONS: These findings highlighted the aggravated impact of the COVID-19 on NSSI, and suggested that individual neuroticism, impulsivity, and self-control traits might be crucial for the development of NSSI behavior among adolescent students. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12888-023-05021-2.